Merge pull request #3398 from snir911/2.4.0-alpha1-branch-bump

# Kata Containers 2.4.0-alpha1

.github/workflows/kata-deploy-test.yaml

@@ -5,60 +5,121 @@ on:
 name: test-kata-deploy
 
 jobs:
-  check_comments:
-    if: ${{ github.event.issue.pull_request }}
+  check-comment-and-membership:
     runs-on: ubuntu-latest
+    if: |
+      github.event.issue.pull_request
+      && github.event_name == 'issue_comment'
+      && github.event.action == 'created'
+      && startsWith(github.event.comment.body, '/test_kata_deploy')
     steps:
-      - name: Check for Command
-        id: command
-        uses: kata-containers/slash-command-action@v1
+      - name: Check membership
+        uses: kata-containers/is-organization-member@1.0.1
+        id: is_organization_member
         with:
-          repo-token: ${{ secrets.GITHUB_TOKEN }}
-          command: "test_kata_deploy"
-          reaction: "true"
-          reaction-type: "eyes"
-          allow-edits: "false"
-          permission-level: admin
-      - name: verify command arg is kata-deploy
+          organization: kata-containers
+          username: ${{ github.event.comment.user.login }}
+          token: ${{ secrets.GITHUB_TOKEN }}
+      - name: Fail if not member
         run: |
-           echo "The command was '${{ steps.command.outputs.command-name }}' with arguments '${{ steps.command.outputs.command-arguments }}'"
+          result=${{ steps.is_organization_member.outputs.result }}
+          if [ $result == false ]; then
+              user=${{ github.event.comment.user.login }}
+              echo Either ${user} is not part of the kata-containers organization
+              echo or ${user} has its Organization Visibility set to Private at
+              echo https://github.com/orgs/kata-containers/people?query=${user}
+              echo 
+              echo Ensure you change your Organization Visibility to Public and
+              echo trigger the test again.
+              exit 1
+          fi
 
-  create-and-test-container:
-    needs: check_comments
+  build-asset:
     runs-on: ubuntu-latest
+    needs: check-comment-and-membership
+    strategy:
+      matrix:
+        asset:
+          - cloud-hypervisor
+          - firecracker
+          - kernel
+          - qemu
+          - rootfs-image
+          - rootfs-initrd
+          - shim-v2
     steps:
-      - name: get-PR-ref
-        id: get-PR-ref
+      - uses: actions/checkout@v2
+      - name: Install docker
         run: |
-            ref=$(cat $GITHUB_EVENT_PATH | jq -r '.issue.pull_request.url' | sed  's#^.*\/pulls#refs\/pull#' | sed 's#$#\/merge#')
-            echo "reference for PR: " ${ref}
-            echo "##[set-output name=pr-ref;]${ref}"
+          curl -fsSL https://test.docker.com -o test-docker.sh
+          sh test-docker.sh
 
-      - name: check out
-        uses: actions/checkout@v2
-        with:
-           ref: ${{ steps.get-PR-ref.outputs.pr-ref }}
-
-      - name: build-container-image
-        id: build-container-image
+      - name: Build ${{ matrix.asset }}
         run: |
-            PR_SHA=$(git log --format=format:%H -n1)
-            VERSION="2.0.0"
-            ARTIFACT_URL="https://github.com/kata-containers/kata-containers/releases/download/${VERSION}/kata-static-${VERSION}-x86_64.tar.xz"
-            wget "${ARTIFACT_URL}" -O tools/packaging/kata-deploy/kata-static.tar.xz
-            docker build --build-arg KATA_ARTIFACTS=kata-static.tar.xz -t katadocker/kata-deploy-ci:${PR_SHA} -t quay.io/kata-containers/kata-deploy-ci:${PR_SHA} ./tools/packaging/kata-deploy
-            docker login -u ${{ secrets.DOCKER_USERNAME }} -p ${{ secrets.DOCKER_PASSWORD }}
-            docker push katadocker/kata-deploy-ci:$PR_SHA
-            docker login -u ${{ secrets.QUAY_DEPLOYER_USERNAME }} -p ${{ secrets.QUAY_DEPLOYER_PASSWORD }} quay.io
-            docker push quay.io/kata-containers/kata-deploy-ci:$PR_SHA
-            echo "##[set-output name=pr-sha;]${PR_SHA}"
-
-      - name: test-kata-deploy-ci-in-aks
-        uses: ./tools/packaging/kata-deploy/action
-        with:
-          packaging-sha: ${{ steps.build-container-image.outputs.pr-sha }}
+          make "${KATA_ASSET}-tarball"
+          build_dir=$(readlink -f build)
+          # store-artifact does not work with symlink
+          sudo cp -r "${build_dir}" "kata-build"
         env:
-          PKG_SHA: ${{ steps.build-container-image.outputs.pr-sha }}
+          KATA_ASSET: ${{ matrix.asset }}
+          TAR_OUTPUT: ${{ matrix.asset }}.tar.gz
+
+      - name: store-artifact ${{ matrix.asset }}
+        uses: actions/upload-artifact@v2
+        with:
+          name: kata-artifacts
+          path: kata-build/kata-static-${{ matrix.asset }}.tar.xz
+          if-no-files-found: error
+
+  create-kata-tarball:
+    runs-on: ubuntu-latest
+    needs: build-asset
+    steps:
+      - uses: actions/checkout@v2
+      - name: get-artifacts
+        uses: actions/download-artifact@v2
+        with:
+          name: kata-artifacts
+          path: kata-artifacts
+      - name: merge-artifacts
+        run: |
+          ./tools/packaging/kata-deploy/local-build/kata-deploy-merge-builds.sh kata-artifacts
+      - name: store-artifacts
+        uses: actions/upload-artifact@v2
+        with:
+          name: kata-static-tarball
+          path: kata-static.tar.xz
+
+  kata-deploy:
+    needs: create-kata-tarball
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v2
+      - name: get-kata-tarball
+        uses: actions/download-artifact@v2
+        with:
+          name: kata-static-tarball
+      - name: build-and-push-kata-deploy-ci
+        id: build-and-push-kata-deploy-ci
+        run: |
+          tag=$(echo $GITHUB_REF | cut -d/ -f3-)
+          pushd $GITHUB_WORKSPACE
+          git checkout $tag
+          pkg_sha=$(git rev-parse HEAD)
+          popd
+          mv kata-static.tar.xz $GITHUB_WORKSPACE/tools/packaging/kata-deploy/kata-static.tar.xz
+          docker build --build-arg KATA_ARTIFACTS=kata-static.tar.xz -t quay.io/kata-containers/kata-deploy-ci:$pkg_sha $GITHUB_WORKSPACE/tools/packaging/kata-deploy
+          docker login -u ${{ secrets.QUAY_DEPLOYER_USERNAME }} -p ${{ secrets.QUAY_DEPLOYER_PASSWORD }} quay.io
+          docker push quay.io/kata-containers/kata-deploy-ci:$pkg_sha
+          mkdir -p packaging/kata-deploy
+          ln -s $GITHUB_WORKSPACE/tools/packaging/kata-deploy/action packaging/kata-deploy/action
+          echo "::set-output name=PKG_SHA::${pkg_sha}"
+      - name: test-kata-deploy-ci-in-aks
+        uses: ./packaging/kata-deploy/action
+        with:
+          packaging-sha: ${{steps.build-and-push-kata-deploy-ci.outputs.PKG_SHA}}
+        env:
+          PKG_SHA: ${{steps.build-and-push-kata-deploy-ci.outputs.PKG_SHA}}
           AZ_APPID: ${{ secrets.AZ_APPID }}
           AZ_PASSWORD: ${{ secrets.AZ_PASSWORD }}
           AZ_SUBSCRIPTION_ID: ${{ secrets.AZ_SUBSCRIPTION_ID }}

.github/workflows/main.yaml

@@ -1,295 +0,0 @@
-name: Publish release tarball
-on: 
-  push: 
-    tags:
-     - '1.*'
-
-jobs:
-  get-artifact-list:
-    runs-on: ubuntu-latest
-    steps:
-      - name: get the list
-        run: |
-         pushd $GITHUB_WORKSPACE
-         tag=$(echo $GITHUB_REF | cut -d/ -f3-)
-         git checkout $tag
-         popd
-         $GITHUB_WORKSPACE/tools/packaging/artifact-list.sh > artifact-list.txt
-      - name: save-artifact-list
-        uses: actions/upload-artifact@master
-        with:
-          name: artifact-list
-          path: artifact-list.txt
-
-  build-kernel:
-    runs-on: ubuntu-16.04
-    needs: get-artifact-list
-    env:
-      buildstr: "install_kernel"
-    steps:
-      - uses: actions/checkout@v1
-      - name: get-artifact-list
-        uses: actions/download-artifact@master
-        with:
-          name: artifact-list
-      - run: |
-         sudo apt-get update && sudo apt install -y flex bison libelf-dev bc iptables
-      - name: build-kernel
-        run: |
-         if grep -q $buildstr ./artifact-list/artifact-list.txt; then
-           $GITHUB_WORKSPACE/.github/workflows/generate-artifact-tarball.sh $buildstr
-           echo "artifact-built=true" >> $GITHUB_ENV
-         else
-           echo "artifact-built=false" >> $GITHUB_ENV
-         fi
-      - name: store-artifacts
-        if: ${{ env.artifact-built }} == 'true'
-        uses: actions/upload-artifact@master
-        with:
-          name: kata-artifacts
-          path: kata-static-kernel.tar.gz
-
-  build-experimental-kernel:
-    runs-on: ubuntu-16.04
-    needs: get-artifact-list
-    env:
-      buildstr: "install_experimental_kernel"
-    steps:
-      - uses: actions/checkout@v1
-      - name: get-artifact-list
-        uses: actions/download-artifact@master
-        with:
-          name: artifact-list
-      - run: |
-         sudo apt-get update && sudo apt install -y flex bison libelf-dev bc iptables
-      - name: build-experimental-kernel
-        run: |
-         if grep -q $buildstr ./artifact-list/artifact-list.txt; then
-           $GITHUB_WORKSPACE/.github/workflows/generate-artifact-tarball.sh $buildstr
-           echo "artifact-built=true" >> $GITHUB_ENV
-         else
-           echo "artifact-built=false" >> $GITHUB_ENV
-         fi
-      - name: store-artifacts
-        if: ${{ env.artifact-built }} == 'true'
-        uses: actions/upload-artifact@master
-        with:
-          name: kata-artifacts
-          path: kata-static-experimental-kernel.tar.gz
-
-  build-qemu:
-    runs-on: ubuntu-16.04
-    needs: get-artifact-list
-    env:
-      buildstr: "install_qemu"
-    steps:
-      - uses: actions/checkout@v1
-      - name: get-artifact-list
-        uses: actions/download-artifact@master
-        with:
-          name: artifact-list
-      - name: build-qemu
-        run: |
-         if grep -q $buildstr ./artifact-list/artifact-list.txt; then
-           $GITHUB_WORKSPACE/.github/workflows/generate-artifact-tarball.sh $buildstr
-           echo "artifact-built=true" >> $GITHUB_ENV
-         else
-           echo "artifact-built=false" >> $GITHUB_ENV
-         fi
-      - name: store-artifacts
-        if: ${{ env.artifact-built }} == 'true'
-        uses: actions/upload-artifact@master
-        with:
-          name: kata-artifacts
-          path: kata-static-qemu.tar.gz
-
-  # Job for building the image
-  build-image:
-    runs-on: ubuntu-16.04
-    needs: get-artifact-list
-    env:
-      buildstr: "install_image"
-    steps:
-      - uses: actions/checkout@v1
-      - name: get-artifact-list
-        uses: actions/download-artifact@master
-        with:
-          name: artifact-list
-      - name: build-image
-        run: |
-         if grep -q $buildstr ./artifact-list/artifact-list.txt; then
-           $GITHUB_WORKSPACE/.github/workflows/generate-artifact-tarball.sh $buildstr
-           echo "artifact-built=true" >> $GITHUB_ENV
-         else
-           echo "artifact-built=false" >> $GITHUB_ENV
-         fi
-      - name: store-artifacts
-        if: ${{ env.artifact-built }} == 'true'
-        uses: actions/upload-artifact@master
-        with:
-          name: kata-artifacts
-          path: kata-static-image.tar.gz
-
-  # Job for building firecracker hypervisor
-  build-firecracker:
-    runs-on: ubuntu-16.04
-    needs: get-artifact-list
-    env:
-      buildstr: "install_firecracker"
-    steps:
-      - uses: actions/checkout@v1
-      - name: get-artifact-list
-        uses: actions/download-artifact@master
-        with:
-          name: artifact-list
-      - name: build-firecracker
-        run: |
-         if grep -q $buildstr ./artifact-list/artifact-list.txt; then
-           $GITHUB_WORKSPACE/.github/workflows/generate-artifact-tarball.sh $buildstr
-           echo "artifact-built=true" >> $GITHUB_ENV
-         else
-           echo "artifact-built=false" >> $GITHUB_ENV
-         fi
-      - name: store-artifacts
-        if: ${{ env.artifact-built }} == 'true'
-        uses: actions/upload-artifact@master
-        with:
-          name: kata-artifacts
-          path: kata-static-firecracker.tar.gz
-
-  # Job for building cloud-hypervisor
-  build-clh:
-    runs-on: ubuntu-16.04
-    needs: get-artifact-list
-    env:
-      buildstr: "install_clh"
-    steps:
-      - uses: actions/checkout@v1
-      - name: get-artifact-list
-        uses: actions/download-artifact@master
-        with:
-          name: artifact-list
-      - name: build-clh
-        run: |
-         if grep -q $buildstr ./artifact-list/artifact-list.txt; then
-           $GITHUB_WORKSPACE/.github/workflows/generate-artifact-tarball.sh $buildstr
-           echo "artifact-built=true" >> $GITHUB_ENV
-         else
-           echo "artifact-built=false" >> $GITHUB_ENV
-         fi
-      - name: store-artifacts
-        if: ${{ env.artifact-built }} == 'true'
-        uses: actions/upload-artifact@master
-        with:
-          name: kata-artifacts
-          path: kata-static-clh.tar.gz
-
-  # Job for building kata components
-  build-kata-components:
-    runs-on: ubuntu-16.04
-    needs: get-artifact-list
-    env:
-      buildstr: "install_kata_components"
-    steps:
-      - uses: actions/checkout@v1
-      - name: get-artifact-list
-        uses: actions/download-artifact@master
-        with:
-          name: artifact-list
-      - name: build-kata-components
-        run: |
-         if grep -q $buildstr ./artifact-list/artifact-list.txt; then
-           $GITHUB_WORKSPACE/.github/workflows/generate-artifact-tarball.sh $buildstr
-           echo "artifact-built=true" >> $GITHUB_ENV
-         else
-           echo "artifact-built=false" >> $GITHUB_ENV
-         fi
-      - name: store-artifacts
-        if: ${{ env.artifact-built }} == 'true'
-        uses: actions/upload-artifact@master
-        with:
-          name: kata-artifacts
-          path: kata-static-kata-components.tar.gz
-
-  gather-artifacts:
-    runs-on: ubuntu-16.04
-    needs: [build-experimental-kernel, build-kernel, build-qemu, build-image, build-firecracker, build-kata-components, build-clh]
-    steps:
-      - uses: actions/checkout@v1
-      - name: get-artifacts
-        uses: actions/download-artifact@master
-        with:
-          name: kata-artifacts
-      - name: colate-artifacts
-        run: |
-          $GITHUB_WORKSPACE/.github/workflows/gather-artifacts.sh
-      - name: store-artifacts
-        uses: actions/upload-artifact@master
-        with:
-          name: release-candidate
-          path: kata-static.tar.xz
-
-  kata-deploy:
-    needs: gather-artifacts
-    runs-on: ubuntu-latest
-    steps:
-      - name: get-artifacts
-        uses: actions/download-artifact@master
-        with:
-          name: release-candidate
-      - name: build-and-push-kata-deploy-ci
-        id: build-and-push-kata-deploy-ci
-        run: |
-          tag=$(echo $GITHUB_REF | cut -d/ -f3-)
-          git clone https://github.com/kata-containers/packaging
-          pushd packaging
-          git checkout $tag
-          pkg_sha=$(git rev-parse HEAD)
-          popd
-          mv release-candidate/kata-static.tar.xz ./packaging/kata-deploy/kata-static.tar.xz
-          docker build --build-arg KATA_ARTIFACTS=kata-static.tar.xz -t katadocker/kata-deploy-ci:$pkg_sha -t quay.io/kata-containers/kata-deploy-ci:$pkg_sha ./packaging/kata-deploy
-          docker login -u ${{ secrets.DOCKER_USERNAME }} -p ${{ secrets.DOCKER_PASSWORD }}
-          docker push katadocker/kata-deploy-ci:$pkg_sha
-          docker login -u ${{ secrets.QUAY_DEPLOYER_USERNAME }} -p ${{ secrets.QUAY_DEPLOYER_PASSWORD }} quay.io
-          docker push quay.io/kata-containers/kata-deploy-ci:$pkg_sha
-          echo "::set-output name=PKG_SHA::${pkg_sha}"
-      - name: test-kata-deploy-ci-in-aks
-        uses: ./packaging/kata-deploy/action
-        with:
-          packaging-sha: ${{steps.build-and-push-kata-deploy-ci.outputs.PKG_SHA}}
-        env:
-          PKG_SHA: ${{steps.build-and-push-kata-deploy-ci.outputs.PKG_SHA}}
-          AZ_APPID: ${{ secrets.AZ_APPID }}
-          AZ_PASSWORD: ${{ secrets.AZ_PASSWORD }}
-          AZ_SUBSCRIPTION_ID: ${{ secrets.AZ_SUBSCRIPTION_ID }}
-          AZ_TENANT_ID: ${{ secrets.AZ_TENANT_ID }}
-      - name: push-tarball
-        run: |
-          # tag the container image we created and push to DockerHub
-          tag=$(echo $GITHUB_REF | cut -d/ -f3-)
-          docker tag katadocker/kata-deploy-ci:${{steps.build-and-push-kata-deploy-ci.outputs.PKG_SHA}} katadocker/kata-deploy:${tag}
-          docker push katadocker/kata-deploy:${tag}
-
-  upload-static-tarball:
-    needs: kata-deploy
-    runs-on: ubuntu-latest
-    steps:
-      - name: download-artifacts
-        uses: actions/download-artifact@master
-        with:
-          name: release-candidate
-      - name: install hub
-        run: |
-          HUB_VER=$(curl -s "https://api.github.com/repos/github/hub/releases/latest" | jq -r .tag_name | sed 's/^v//')
-          wget -q -O- https://github.com/github/hub/releases/download/v$HUB_VER/hub-linux-amd64-$HUB_VER.tgz | \
-          tar xz --strip-components=2 --wildcards '*/bin/hub' && sudo mv hub /usr/local/bin/hub
-      - name: push static tarball to github
-        run: |
-          tag=$(echo $GITHUB_REF | cut -d/ -f3-)
-          tarball="kata-static-$tag-x86_64.tar.xz"
-          repo="https://github.com/kata-containers/runtime.git"
-          mv release-candidate/kata-static.tar.xz "release-candidate/${tarball}"
-          git clone "${repo}"
-          cd runtime
-          echo "uploading asset '${tarball}' to '${repo}' tag: ${tag}"
-          GITHUB_TOKEN=${{ secrets.GIT_UPLOAD_TOKEN }} hub release edit -m "" -a "../release-candidate/${tarball}" "${tag}"

.github/workflows/release.yaml

@@ -149,3 +149,31 @@ jobs:
           tar -cvzf "${tarball}" src/agent/.cargo/config src/agent/vendor
           GITHUB_TOKEN=${{ secrets.GIT_UPLOAD_TOKEN }} hub release edit -m "" -a "${tarball}" "${tag}" 
           popd
+
+  upload-libseccomp-tarball:
+    needs: upload-cargo-vendored-tarball
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v2
+      - name: download-and-upload-tarball
+        env:
+          GITHUB_TOKEN: ${{ secrets.GIT_UPLOAD_TOKEN }}
+          GOPATH: ${HOME}/go
+        run: |
+          pushd $GITHUB_WORKSPACE
+          ./ci/install_yq.sh
+          tag=$(echo $GITHUB_REF | cut -d/ -f3-)
+          versions_yaml="versions.yaml"
+          version=$(${GOPATH}/bin/yq read ${versions_yaml} "externals.libseccomp.version")
+          repo_url=$(${GOPATH}/bin/yq read ${versions_yaml} "externals.libseccomp.url")
+          download_url="${repo_url}/releases/download/v${version}"
+          tarball="libseccomp-${version}.tar.gz"
+          asc="${tarball}.asc"
+          curl -sSLO "${download_url}/${tarball}"
+          curl -sSLO "${download_url}/${asc}"
+          # "-m" option should be empty to re-use the existing release title
+          # without opening a text editor.
+          # For the details, check https://hub.github.com/hub-release.1.html.
+          hub release edit -m "" -a "${tarball}" "${tag}"
+          hub release edit -m "" -a "${asc}" "${tag}"
+          popd

.github/workflows/static-checks.yaml

@@ -13,7 +13,7 @@ jobs:
   test:
     strategy:
       matrix:
-        go-version: [1.15.x, 1.16.x]
+        go-version: [1.16.x, 1.17.x]
         os: [ubuntu-20.04]
     runs-on: ${{ matrix.os }}
     env:
@@ -67,6 +67,14 @@ jobs:
         PATH=$PATH:"$HOME/.cargo/bin"
         rustup target add x86_64-unknown-linux-musl
         rustup component add rustfmt clippy
+    - name: Setup seccomp
+      run: |
+        libseccomp_install_dir=$(mktemp -d -t libseccomp.XXXXXXXXXX)
+        gperf_install_dir=$(mktemp -d -t gperf.XXXXXXXXXX)
+        cd ${GOPATH}/src/github.com/${{ github.repository }} && ./ci/install_libseccomp.sh "${libseccomp_install_dir}" "${gperf_install_dir}"
+        echo "Set environment variables for the libseccomp crate to link the libseccomp library statically"
+        echo "LIBSECCOMP_LINK_TYPE=static" >> $GITHUB_ENV
+        echo "LIBSECCOMP_LIB_PATH=${libseccomp_install_dir}/lib" >> $GITHUB_ENV
     # Check whether the vendored code is up-to-date & working as the first thing
     - name: Check vendored code
       if: ${{ !contains(github.event.pull_request.labels.*.name, 'force-skip-ci') }}

Makefile

@@ -8,20 +8,25 @@ COMPONENTS =
 
 COMPONENTS += agent
 COMPONENTS += runtime
-COMPONENTS += trace-forwarder
 
 # List of available tools
 TOOLS =
 
 TOOLS += agent-ctl
+TOOLS += trace-forwarder
 
 STANDARD_TARGETS = build check clean install test vendor
 
+default: all
+
+all: logging-crate-tests build
+
+logging-crate-tests:
+	make -C src/libs/logging
+
 include utils.mk
 include ./tools/packaging/kata-deploy/local-build/Makefile
 
-all: build
-
 # Create the rules
 $(eval $(call create_all_rules,$(COMPONENTS),$(TOOLS),$(STANDARD_TARGETS)))
 
@@ -34,4 +39,10 @@ generate-protocols:
 static-checks: build
 	bash ci/static-checks.sh
 
-.PHONY: all default static-checks binary-tarball install-binary-tarball
+.PHONY: \
+	all \
+	binary-tarball \
+	default \
+	install-binary-tarball \
+	logging-crate-tests \
+	static-checks

README.md

@@ -70,8 +70,8 @@ The table below lists the remaining parts of the project:
 | [packaging](tools/packaging) | infrastructure | Scripts and metadata for producing packaged binaries<br/>(components, hypervisors, kernel and rootfs). |
 | [kernel](https://www.kernel.org) | kernel | Linux kernel used by the hypervisor to boot the guest image. Patches are stored [here](tools/packaging/kernel). |
 | [osbuilder](tools/osbuilder) | infrastructure | Tool to create "mini O/S" rootfs and initrd images and kernel for the hypervisor. |
-| [`agent-ctl`](tools/agent-ctl) | utility | Tool that provides low-level access for testing the agent. |
-| [`trace-forwarder`](src/trace-forwarder) | utility | Agent tracing helper. |
+| [`agent-ctl`](src/tools/agent-ctl) | utility | Tool that provides low-level access for testing the agent. |
+| [`trace-forwarder`](src/tools/trace-forwarder) | utility | Agent tracing helper. |
 | [`ci`](https://github.com/kata-containers/ci) | CI | Continuous Integration configuration files and scripts. |
 | [`katacontainers.io`](https://github.com/kata-containers/www.katacontainers.io) | Source for the [`katacontainers.io`](https://www.katacontainers.io) site. |
 

VERSION

@@ -1 +1 @@
-2.3.0-alpha2
+2.4.0-alpha1

ci/go-no-os-exit.sh

@@ -1,30 +0,0 @@
-#!/bin/bash
-# Copyright (c) 2018 Intel Corporation
-#
-# SPDX-License-Identifier: Apache-2.0
-#
-# Check there are no os.Exit() calls creeping into the code
-# We don't use that exit path in the Kata codebase.
-
-# Allow the path to check to be over-ridden.
-# Default to the current directory.
-go_packages=${1:-.}
-
-echo "Checking for no os.Exit() calls for package [${go_packages}]"
-
-candidates=`go list -f '{{.Dir}}/*.go' $go_packages`
-for f in $candidates; do
-	filename=`basename $f`
-	# skip all go test files
-	[[ $filename == *_test.go ]] && continue
-	# skip exit.go where, the only file we should call os.Exit() from.
-	[[ $filename == "exit.go" ]] && continue
-	files="$f $files"
-done
-
-[ -z "$files" ] && echo "No files to check, skipping" && exit 0
-
-if egrep -n '\<os\.Exit\>' $files; then
-	echo "Direct calls to os.Exit() are forbidden, please use exit() so atexit() works"
-	exit 1
-fi

ci/go-test.sh

@@ -1,3 +1,4 @@
+#!/bin/bash
 #
 # Copyright (c) 2020 Intel Corporation
 #

ci/install_libseccomp.sh

@@ -0,0 +1,110 @@
+#!/bin/bash
+#
+# Copyright 2021 Sony Group Corporation
+#
+# SPDX-License-Identifier: Apache-2.0
+#
+
+set -o errexit
+
+cidir=$(dirname "$0")
+source "${cidir}/lib.sh"
+
+clone_tests_repo
+
+source "${tests_repo_dir}/.ci/lib.sh"
+
+# The following variables if set on the environment will change the behavior
+# of gperf and libseccomp configure scripts, that may lead this script to
+# fail. So let's ensure they are unset here.
+unset PREFIX DESTDIR
+
+arch=$(uname -m)
+workdir="$(mktemp -d --tmpdir build-libseccomp.XXXXX)"
+
+# Variables for libseccomp
+# Currently, specify the libseccomp version directly without using `versions.yaml`
+# because the current Snap workflow is incomplete.
+# After solving the issue, replace this code by using the `versions.yaml`.
+# libseccomp_version=$(get_version "externals.libseccomp.version")
+# libseccomp_url=$(get_version "externals.libseccomp.url")
+libseccomp_version="2.5.1"
+libseccomp_url="https://github.com/seccomp/libseccomp"
+libseccomp_tarball="libseccomp-${libseccomp_version}.tar.gz"
+libseccomp_tarball_url="${libseccomp_url}/releases/download/v${libseccomp_version}/${libseccomp_tarball}"
+cflags="-O2"
+
+# Variables for gperf
+# Currently, specify the gperf version directly without using `versions.yaml`
+# because the current Snap workflow is incomplete.
+# After solving the issue, replace this code by using the `versions.yaml`.
+# gperf_version=$(get_version "externals.gperf.version")
+# gperf_url=$(get_version "externals.gperf.url")
+gperf_version="3.1"
+# XXX: gnu.org currently unavailable - see https://github.com/kata-containers/kata-containers/issues/3314
+gperf_url="https://www.mirrorservice.org/sites/ftp.gnu.org/gnu/gperf"
+gperf_tarball="gperf-${gperf_version}.tar.gz"
+gperf_tarball_url="${gperf_url}/${gperf_tarball}"
+
+# We need to build the libseccomp library from sources to create a static library for the musl libc.
+# However, ppc64le and s390x have no musl targets in Rust. Hence, we do not set cflags for the musl libc.
+if ([ "${arch}" != "ppc64le" ] && [ "${arch}" != "s390x" ]); then
+    # Set FORTIFY_SOURCE=1 because the musl-libc does not have some functions about FORTIFY_SOURCE=2
+    cflags="-U_FORTIFY_SOURCE -D_FORTIFY_SOURCE=1 -O2"
+fi
+
+die() {
+    msg="$*"
+    echo "[Error] ${msg}" >&2
+    exit 1
+}
+
+finish() {
+    rm -rf "${workdir}"
+}
+
+trap finish EXIT
+
+build_and_install_gperf() {
+    echo "Build and install gperf version ${gperf_version}"
+    mkdir -p "${gperf_install_dir}"
+    curl -sLO "${gperf_tarball_url}"
+    tar -xf "${gperf_tarball}"
+    pushd "gperf-${gperf_version}"
+    ./configure --prefix="${gperf_install_dir}"
+    make
+    make install
+    export PATH=$PATH:"${gperf_install_dir}"/bin
+    popd
+    echo "Gperf installed successfully"
+}
+
+build_and_install_libseccomp() {
+    echo "Build and install libseccomp version ${libseccomp_version}"
+    mkdir -p "${libseccomp_install_dir}"
+    curl -sLO "${libseccomp_tarball_url}"
+    tar -xf "${libseccomp_tarball}"
+    pushd "libseccomp-${libseccomp_version}"
+    ./configure --prefix="${libseccomp_install_dir}" CFLAGS="${cflags}" --enable-static
+    make
+    make install
+    popd
+    echo "Libseccomp installed successfully"
+}
+
+main() {
+    local libseccomp_install_dir="${1:-}"
+    local gperf_install_dir="${2:-}"
+
+    if [ -z "${libseccomp_install_dir}" ] || [ -z "${gperf_install_dir}" ]; then
+        die "Usage: ${0} <libseccomp-install-dir> <gperf-install-dir>"
+    fi
+
+    pushd "$workdir"
+    # gperf is required for building the libseccomp.
+    build_and_install_gperf
+    build_and_install_libseccomp
+    popd
+}
+
+main "$@"

ci/install_rust.sh

@@ -12,5 +12,5 @@ source "${cidir}/lib.sh"
 clone_tests_repo
 
 pushd ${tests_repo_dir}
-.ci/install_rust.sh
+.ci/install_rust.sh ${1:-}
 popd

ci/openshift-ci/images/Dockerfile.buildroot

@@ -6,4 +6,9 @@
 #
 FROM registry.centos.org/centos:8
 
-RUN yum -y update && yum -y install git sudo wget
+RUN yum -y update && \
+    yum -y install \
+    git \
+    sudo \
+    wget && \
+    yum clean all

docs/Developer-Guide.md

@@ -86,6 +86,16 @@ One of the `initrd` and `image` options in Kata runtime config file **MUST** be
 The main difference between the options is that the size of `initrd`(10MB+) is significantly smaller than
 rootfs `image`(100MB+).
 
+## Enable seccomp
+
+Enable seccomp as follows:
+
+```
+$ sudo sed -i '/^disable_guest_seccomp/ s/true/false/' /etc/kata-containers/configuration.toml
+```
+
+This will pass container seccomp profiles to the kata agent.
+
 ## Enable full debug
 
 Enable full debug as follows:
@@ -216,6 +226,18 @@ $ go get -d -u github.com/kata-containers/kata-containers
 $ cd $GOPATH/src/github.com/kata-containers/kata-containers/src/agent && make
 ```
 
+The agent is built with seccomp capability by default.
+If you want to build the agent without the seccomp capability, you need to run `make` with `SECCOMP=no` as follows.
+
+```
+$ make -C $GOPATH/src/github.com/kata-containers/kata-containers/src/agent SECCOMP=no
+```
+
+> **Note:**
+>
+> - If you enable seccomp in the main configuration file but build the agent without seccomp capability,
+>   the runtime exits conservatively with an error message.
+
 ## Get the osbuilder
 
 ```
@@ -234,9 +256,21 @@ the following example.
 $ export ROOTFS_DIR=${GOPATH}/src/github.com/kata-containers/kata-containers/tools/osbuilder/rootfs-builder/rootfs
 $ sudo rm -rf ${ROOTFS_DIR}
 $ cd $GOPATH/src/github.com/kata-containers/kata-containers/tools/osbuilder/rootfs-builder
-$ script -fec 'sudo -E GOPATH=$GOPATH USE_DOCKER=true SECCOMP=no ./rootfs.sh ${distro}'
+$ script -fec 'sudo -E GOPATH=$GOPATH USE_DOCKER=true ./rootfs.sh ${distro}'
+```
+
+You MUST choose a distribution (e.g., `ubuntu`) for `${distro}`.
+You can get a supported distributions list in the Kata Containers by running the following.
+
+```
+$ ./rootfs.sh -l
+```
+
+If you want to build the agent without seccomp capability, you need to run the `rootfs.sh` script with `SECCOMP=no` as follows.
+
+```
+$ script -fec 'sudo -E GOPATH=$GOPATH AGENT_INIT=yes USE_DOCKER=true SECCOMP=no ./rootfs.sh ${distro}'
 ```
-You MUST choose one of `alpine`, `centos`, `clearlinux`, `debian`, `euleros`, `fedora`, `suse`, and `ubuntu` for `${distro}`. By default `seccomp` packages are not included in the rootfs image. Set `SECCOMP` to `yes` to include them.
 
 > **Note:**
 >
@@ -272,6 +306,7 @@ $ script -fec 'sudo -E USE_DOCKER=true ./image_builder.sh ${ROOTFS_DIR}'
 > - If you do *not* wish to build under Docker, remove the `USE_DOCKER`
 >   variable in the previous command and ensure the `qemu-img` command is
 >   available on your system.
+>   - If `qemu-img` is not installed, you will likely see errors such as `ERROR: File /dev/loop19p1 is not a block device` and `losetup: /tmp/tmp.bHz11oY851: Warning: file is smaller than 512 bytes; the loop device may be useless or invisible for system tools`. These can be mitigated by installing the `qemu-img` command (available in the `qemu-img` package on Fedora or the `qemu-utils` package on Debian).
 
 
 ### Install the rootfs image
@@ -290,12 +325,23 @@ $ (cd /usr/share/kata-containers && sudo ln -sf "$image" kata-containers.img)
 $ export ROOTFS_DIR="${GOPATH}/src/github.com/kata-containers/kata-containers/tools/osbuilder/rootfs-builder/rootfs"
 $ sudo rm -rf ${ROOTFS_DIR}
 $ cd $GOPATH/src/github.com/kata-containers/kata-containers/tools/osbuilder/rootfs-builder
-$ script -fec 'sudo -E GOPATH=$GOPATH AGENT_INIT=yes USE_DOCKER=true SECCOMP=no ./rootfs.sh ${distro}'
+$ script -fec 'sudo -E GOPATH=$GOPATH AGENT_INIT=yes USE_DOCKER=true ./rootfs.sh ${distro}'
 ```
 `AGENT_INIT` controls if the guest image uses the Kata agent as the guest `init` process. When you create an initrd image,
-always set `AGENT_INIT` to `yes`. By default `seccomp` packages are not included in the initrd image. Set `SECCOMP` to `yes` to include them.
+always set `AGENT_INIT` to `yes`.
 
-You MUST choose one of `alpine`, `centos`, `clearlinux`, `euleros`, and `fedora` for `${distro}`.
+You MUST choose a distribution (e.g., `ubuntu`) for `${distro}`.
+You can get a supported distributions list in the Kata Containers by running the following.
+
+```
+$ ./rootfs.sh -l
+```
+
+If you want to build the agent without seccomp capability, you need to run the `rootfs.sh` script with `SECCOMP=no` as follows.
+
+```
+$ script -fec 'sudo -E GOPATH=$GOPATH AGENT_INIT=yes USE_DOCKER=true SECCOMP=no ./rootfs.sh ${distro}'
+```
 
 > **Note:**
 >

docs/Limitations.md

@@ -86,21 +86,6 @@ All other configurations are supported and are working properly.
 
 ## Networking
 
-### Docker swarm and compose support
-
-The newest version of Docker supported is specified by the
-`externals.docker.version` variable in the
-[versions database](https://github.com/kata-containers/runtime/blob/master/versions.yaml).
-
-Basic Docker swarm support works. However, if you want to use custom networks
-with Docker's swarm, an older version of Docker is required. This is specified
-by the `externals.docker.meta.swarm-version` variable in the
-[versions database](https://github.com/kata-containers/runtime/blob/master/versions.yaml).
-
-See issue https://github.com/kata-containers/runtime/issues/175 for more information.
-
-Docker compose normally uses custom networks, so also has the same limitations.
-
 ## Resource management
 
 Due to the way VMs differ in their CPU and memory allocation, and sharing

docs/README.md

@@ -11,6 +11,10 @@ For details of the other Kata Containers repositories, see the
 
 * [Installation guides](./install/README.md): Install and run Kata Containers with Docker or Kubernetes
 
+## Tracing
+
+See the [tracing documentation](tracing.md).
+
 ## More User Guides
 
 * [Upgrading](Upgrading.md): how to upgrade from [Clear Containers](https://github.com/clearcontainers) and [runV](https://github.com/hyperhq/runv) to [Kata Containers](https://github.com/kata-containers) and how to upgrade an existing Kata Containers system to the latest version.
@@ -37,7 +41,7 @@ Documents that help to understand and contribute to Kata Containers.
 
 ### Design and Implementations
 
-* [Kata Containers Architecture](design/architecture.md): Architectural overview of Kata Containers
+* [Kata Containers Architecture](design/architecture): Architectural overview of Kata Containers
 * [Kata Containers E2E Flow](design/end-to-end-flow.md): The entire end-to-end flow of Kata Containers
 * [Kata Containers design](./design/README.md): More Kata Containers design documents
 * [Kata Containers threat model](./threat-model/threat-model.md): Kata Containers threat model
@@ -48,6 +52,18 @@ Documents that help to understand and contribute to Kata Containers.
 * [How to contribute to Kata Containers](https://github.com/kata-containers/community/blob/master/CONTRIBUTING.md)
 * [Code of Conduct](../CODE_OF_CONDUCT.md)
 
+## Help Writing a Code PR
+
+* [Code PR advice](code-pr-advice.md).
+
+## Help Writing Unit Tests
+
+* [Unit Test Advice](Unit-Test-Advice.md)
+
+## Help Improving the Documents
+
+* [Documentation Requirements](Documentation-Requirements.md)
+
 ### Code Licensing
 
 * [Licensing](Licensing-strategy.md): About the licensing strategy of Kata Containers.
@@ -57,10 +73,6 @@ Documents that help to understand and contribute to Kata Containers.
 * [Release strategy](Stable-Branch-Strategy.md)
 * [Release Process](Release-Process.md)
 
-## Help Improving the Documents
-
-* [Documentation Requirements](Documentation-Requirements.md)
-
 ## Website Changes
 
 If you have a suggestion for how we can improve the

docs/Release-Process.md

@@ -64,7 +64,7 @@
 
 ### Check Git-hub Actions
 
-  We make use of [GitHub actions](https://github.com/features/actions) in this [file](https://github.com/kata-containers/kata-containers/blob/main/.github/workflows/main.yaml) in the `kata-containers/kata-containers` repository to build and upload release artifacts. This action is auto triggered with the above step when a new tag is pushed to the `kata-containers/kata-containers` repository.
+  We make use of [GitHub actions](https://github.com/features/actions) in this [file](https://github.com/kata-containers/kata-containers/blob/main/.github/workflows/release.yaml) in the `kata-containers/kata-containers` repository to build and upload release artifacts. This action is auto triggered with the above step when a new tag is pushed to the `kata-containers/kata-containers` repository.
 
   Check the [actions status page](https://github.com/kata-containers/kata-containers/actions) to verify all steps in the actions workflow have completed successfully. On success, a static tarball containing Kata release artifacts will be uploaded to the [Release page](https://github.com/kata-containers/kata-containers/releases).
 

docs/Stable-Branch-Strategy.md

@@ -120,7 +120,7 @@ stable and main. While this is not in place currently, it should be considered i
 
 ### Patch releases
 
-Releases are made every three weeks, which include a GitHub release as
+Releases are made every four weeks, which include a GitHub release as
 well as binary packages. These patch releases are made for both stable branches, and a "release candidate"
 for the next `MAJOR` or `MINOR` is created from main. If there are no changes across all the repositories, no
 release is created and an announcement is made on the developer mailing list to highlight this.
@@ -136,8 +136,7 @@ The process followed for making a release can be found at [Release Process](Rele
 
 ###  Frequency
 Minor releases are less frequent in order to provide a more stable baseline for users. They are currently
-running on a twelve week cadence. As the Kata Containers code base has reached a certain level of 
-maturity, we have increased the cadence from six weeks to twelve weeks. The release schedule can be seen on the
+running on a sixteen weeks cadence. The release schedule can be seen on the
 [release rotation wiki page](https://github.com/kata-containers/community/wiki/Release-Team-Rota).
 
 ### Compatibility

docs/Unit-Test-Advice.md

@@ -0,0 +1,379 @@
+# Unit Test Advice
+
+## Overview
+
+This document offers advice on writing a Unit Test (UT) in
+[Golang](https://golang.org) and [Rust](https://www.rust-lang.org).
+
+## General advice
+
+### Unit test strategies
+
+#### Positive and negative tests
+
+Always add positive tests (where success is expected) *and* negative
+tests (where failure is expected).
+
+#### Boundary condition tests
+
+Try to add unit tests that exercise boundary conditions such as:
+
+- Missing values (`null` or `None`).
+- Empty strings and huge strings.
+- Empty (or uninitialised) complex data structures
+  (such as lists, vectors and hash tables).
+- Common numeric values (such as `-1`, `0`, `1` and the minimum and
+  maximum values).
+
+#### Test unusual values
+
+Also always consider "unusual" input values such as:
+
+- String values containing spaces, Unicode characters, special
+  characters, escaped characters or null bytes.
+
+  > **Note:** Consider these unusual values in prefix, infix and
+  > suffix position.
+
+- String values that cannot be converted into numeric values or which
+  contain invalid structured data (such as invalid JSON).
+
+#### Other types of tests
+
+If the code requires other forms of testing (such as stress testing,
+fuzz testing and integration testing), raise a GitHub issue and
+reference it on the issue you are using for the main work. This
+ensures the test team are aware that a new test is required.
+
+### Test environment
+
+#### Create unique files and directories
+
+Ensure your tests do not write to a fixed file or directory. This can
+cause problems when running multiple tests simultaneously and also
+when running tests after a previous test run failure.
+
+#### Assume parallel testing
+
+Always assume your tests will be run *in parallel*. If this is
+problematic for a test, force it to run in isolation using the
+`serial_test` crate for Rust code for example.
+
+### Running
+
+Ensure you run the unit tests and they all pass before raising a PR.
+Ideally do this on different distributions on different architectures
+to maximise coverage (and so minimise surprises when your code runs in
+the CI).
+
+## Assertions
+
+### Golang assertions
+
+Use the `testify` assertions package to create a new assertion object as this
+keeps the test code free from distracting `if` tests:
+
+```go
+func TestSomething(t *testing.T) {
+    assert := assert.New(t)
+
+    err := doSomething()
+    assert.NoError(err)
+}
+```
+
+### Rust assertions
+
+Use the standard set of `assert!()` macros.
+
+## Table driven tests
+
+Try to write tests using a table-based approach. This allows you to distill
+the logic into a compact table (rather than spreading the tests across
+multiple test functions). It also makes it easy to cover all the
+interesting boundary conditions:
+
+### Golang table driven tests
+
+Assume the following function:
+
+```go
+// The function under test.
+//
+// Accepts a string and an integer and returns the
+// result of sticking them together separated by a dash as a string.
+func joinParamsWithDash(str string, num int) (string, error) {
+    if str == "" {
+        return "", errors.New("string cannot be blank")
+    }
+
+    if num <= 0 {
+        return "", errors.New("number must be positive")
+    }
+
+    return fmt.Sprintf("%s-%d", str, num), nil
+}
+```
+
+A table driven approach to testing it:
+
+```go
+import (
+    "testing"
+    "github.com/stretchr/testify/assert"
+)
+
+func TestJoinParamsWithDash(t *testing.T) {
+    assert := assert.New(t)
+
+    // Type used to hold function parameters and expected results.
+    type testData struct {
+        param1         string
+        param2         int
+        expectedResult string
+        expectError    bool
+    }
+
+    // List of tests to run including the expected results
+    data := []testData{
+        // Failure scenarios
+        {"", -1, "", true},
+        {"", 0, "", true},
+        {"", 1, "", true},
+        {"foo", 0, "", true},
+        {"foo", -1, "", true},
+
+        // Success scenarios
+        {"foo", 1, "foo-1", false},
+        {"bar", 42, "bar-42", false},
+    }
+
+    // Run the tests
+    for i, d := range data {
+        // Create a test-specific string that is added to each assert
+        // call. It will be displayed if any assert test fails.
+        msg := fmt.Sprintf("test[%d]: %+v", i, d)
+
+        // Call the function under test
+        result, err := joinParamsWithDash(d.param1, d.param2)
+
+        // update the message for more information on failure
+        msg = fmt.Sprintf("%s, result: %q, err: %v", msg, result, err)
+
+        if d.expectError {
+            assert.Error(err, msg)
+
+            // If an error is expected, there is no point
+            // performing additional checks.
+            continue
+        }
+
+        assert.NoError(err, msg)
+        assert.Equal(d.expectedResult, result, msg)
+    }
+}
+```
+
+### Rust table driven tests
+
+Assume the following function:
+
+```rust
+// Convenience type to allow Result return types to only specify the type
+// for the true case; failures are specified as static strings.
+// XXX: This is an example. In real code use the "anyhow" and
+// XXX: "thiserror" crates.
+pub type Result<T> = std::result::Result<T, &'static str>;
+
+// The function under test.
+//
+// Accepts a string and an integer and returns the
+// result of sticking them together separated by a dash as a string.
+fn join_params_with_dash(str: &str, num: i32) -> Result<String> {
+    if str.is_empty() {
+        return Err("string cannot be blank");
+    }
+
+    if num <= 0 {
+        return Err("number must be positive");
+    }
+
+    let result = format!("{}-{}", str, num);
+
+    Ok(result)
+}
+
+```
+
+A table driven approach to testing it:
+
+```rust
+#[cfg(test)]
+mod tests {
+    use super::*;
+
+    #[test]
+    fn test_join_params_with_dash() {
+        // This is a type used to record all details of the inputs
+        // and outputs of the function under test.
+        #[derive(Debug)]
+        struct TestData<'a> {
+            str: &'a str,
+            num: i32,
+            result: Result<String>,
+        }
+
+        // The tests can now be specified as a set of inputs and outputs
+        let tests = &[
+            // Failure scenarios
+            TestData {
+                str: "",
+                num: 0,
+                result: Err("string cannot be blank"),
+            },
+            TestData {
+                str: "foo",
+                num: -1,
+                result: Err("number must be positive"),
+            },
+
+            // Success scenarios
+            TestData {
+                str: "foo",
+                num: 42,
+                result: Ok("foo-42".to_string()),
+            },
+            TestData {
+                str: "-",
+                num: 1,
+                result: Ok("--1".to_string()),
+            },
+        ];
+
+        // Run the tests
+        for (i, d) in tests.iter().enumerate() {
+            // Create a string containing details of the test
+            let msg = format!("test[{}]: {:?}", i, d);
+
+            // Call the function under test
+            let result = join_params_with_dash(d.str, d.num);
+
+            // Update the test details string with the results of the call
+            let msg = format!("{}, result: {:?}", msg, result);
+
+            // Perform the checks
+            if d.result.is_ok() {
+                assert!(result == d.result, msg);
+                continue;
+            }
+
+            let expected_error = format!("{}", d.result.as_ref().unwrap_err());
+            let actual_error = format!("{}", result.unwrap_err());
+            assert!(actual_error == expected_error, msg);
+        }
+    }
+}
+```
+
+## Temporary files
+
+Always delete temporary files on success.
+
+### Golang temporary files
+
+```go
+func TestSomething(t *testing.T) {
+    assert := assert.New(t)
+
+    // Create a temporary directory
+    tmpdir, err := os.MkdirTemp("", "")
+    assert.NoError(err)
+
+    // Delete it at the end of the test
+    defer os.RemoveAll(tmpdir) 
+
+    // Add test logic that will use the tmpdir here...
+}
+```
+
+### Rust temporary files
+
+Use the `tempfile` crate which allows files and directories to be deleted
+automatically:
+
+```rust
+#[cfg(test)]
+mod tests {
+    use tempfile::tempdir;
+
+    #[test]
+    fn test_something() {
+
+        // Create a temporary directory (which will be deleted automatically
+        let dir = tempdir().expect("failed to create tmpdir");
+
+        let filename = dir.path().join("file.txt");
+
+        // create filename ...
+    }
+}
+
+```
+
+## Test user
+
+[Unit tests are run *twice*](https://github.com/kata-containers/tests/blob/main/.ci/go-test.sh):
+
+- as the current user
+- as the `root` user (if different to the current user)
+
+When writing a test consider which user should run it; even if the code the
+test is exercising runs as `root`, it may be necessary to *only* run the test
+as a non-`root` for the test to be meaningful. Add appropriate skip
+guards around code that requires `root` and non-`root` so that the test
+will run if the correct type of user is detected and skipped if not.
+
+### Run Golang tests as a different user
+
+The main repository has the most comprehensive set of skip abilities. See:
+
+- https://github.com/kata-containers/kata-containers/tree/main/src/runtime/pkg/katatestutils
+
+### Run Rust tests as a different user
+
+One method is to use the `nix` crate along with some custom macros:
+
+```
+#[cfg(test)]
+mod tests {
+    #[allow(unused_macros)]
+    macro_rules! skip_if_root {
+        () => {
+            if nix::unistd::Uid::effective().is_root() {
+                println!("INFO: skipping {} which needs non-root", module_path!());
+                return;
+            }
+        };
+    }
+
+    #[allow(unused_macros)]
+    macro_rules! skip_if_not_root {
+        () => {
+            if !nix::unistd::Uid::effective().is_root() {
+                println!("INFO: skipping {} which needs root", module_path!());
+                return;
+            }
+        };
+    }
+
+    #[test]
+    fn test_that_must_be_run_as_root() {
+        // Not running as the superuser, so skip.
+        skip_if_not_root!();
+
+        // Run test *iff* the user running the test is root
+
+        // ...
+    }
+}
+```

docs/Upgrading.md

@@ -102,7 +102,7 @@ first
 [install the latest release](#determine-latest-version).
 
 See the
-[manual installation installation documentation](install/README.md#manual-installation)
+[manual installation documentation](install/README.md#manual-installation)
 for details on how to automatically install and configuration a static release
 with containerd.
 
@@ -114,7 +114,7 @@ with containerd.
 > kernel or image.
 
 If you are using custom
-[guest assets](design/architecture.md#guest-assets),
+[guest assets](design/architecture/README.md#guest-assets),
 you must upgrade them to work with Kata Containers 2.x since Kata
 Containers 1.x assets will **not** work.
 

docs/code-pr-advice.md

@@ -0,0 +1,247 @@
+# Code PR Advice
+
+Before raising a PR containing code changes, we suggest you consider
+the following to ensure a smooth and fast process.
+
+> **Note:**
+>
+> - All the advice in this document is optional. However, if the
+>   advice provided is not followed, there is no guarantee your PR
+>   will be merged.
+>
+> - All the check tools will be run automatically on your PR by the CI.
+>   However, if you run them locally first, there is a much better
+>   chance of a successful initial CI run.
+
+## Assumptions
+
+This document assumes you have already read (and in the case of the
+code of conduct agreed to):
+
+- The [Kata Containers code of conduct](https://github.com/kata-containers/community/blob/main/CODE_OF_CONDUCT.md).
+- The [Kata Containers contributing guide](https://github.com/kata-containers/community/blob/main/CONTRIBUTING.md).
+
+## Code
+
+### Architectures
+
+Do not write architecture-specific code if it is possible to write the
+code generically.
+
+### General advice
+
+- Do not write code to impress: instead write code that is easy to read and understand.
+
+- Always consider which user will run the code. Try to minimise
+  the privileges the code requires.
+
+### Comments
+
+Always add comments if the intent of the code is not obvious. However,
+try to avoid comments if the code could be made clearer (for example
+by using more meaningful variable names).
+
+### Constants
+
+Don't embed magic numbers and strings in functions, particularly if
+they are used repeatedly.
+
+Create constants at the top of the file instead.
+
+### Copyright and license
+
+Ensure all new files contain a copyright statement and an SPDX license
+identifier in the comments at the top of the file.
+
+### FIXME and TODO
+
+If the code contains areas that are not fully implemented, make this
+clear a comment which provides a link to a GitHub issue that provides
+further information.
+
+Do not just rely on comments in this case though: if possible, return
+a "`BUG: feature X not implemented see {bug-url}`" type error.
+
+### Functions
+
+- Keep functions relatively short (less than 100 lines is a good "rule of thumb").
+
+- Document functions if the parameters, return value or general intent
+  of the function is not obvious.
+
+- Always return errors where possible.
+
+  Do not discard error return values from the functions this function
+  calls.
+
+### Logging
+
+- Don't use multiple log calls when a single log call could be used.
+
+- Use structured logging where possible to allow
+  [standard tooling](https://github.com/kata-containers/tests/tree/main/cmd/log-parser)
+  be able to extract the log fields.
+
+### Names
+
+Give functions, macros and variables clear and meaningful names.
+
+### Structures
+
+#### Golang structures
+
+Unlike Rust, Go does not enforce that all structure members be set.
+This has lead to numerous bugs in the past where code like the
+following is used:
+
+```go
+type Foo struct {
+    Key   string
+    Value string
+}
+
+// BUG: Key not set, but nobody noticed! ;(
+let foo1 = Foo {
+    Value: "foo",
+}
+```
+
+A much safer approach is to create a constructor function to enforce
+integrity:
+
+```go
+type Foo struct {
+    Key   string
+    Value string
+}
+
+func NewFoo(key, value string) (*Foo, error) {
+    if key == "" {
+        return nil, errors.New("Foo needs a key")
+    }
+
+    if value == "" {
+        return nil, errors.New("Foo needs a value")
+    }
+
+    return &Foo{
+        Key:   key,
+        Value: value,
+    }, nil
+}
+
+func testFoo() error {
+    // BUG: Key not set, but nobody noticed! ;(
+    badFoo := Foo{Value: "value"}
+
+    // Ok - the constructor performs needed validation
+    goodFoo, err := NewFoo("name", "value")
+    if err != nil {
+        return err
+    }
+
+    return nil
+```
+
+> **Note:**
+>
+> The above is just an example. The *safest* approach would be to move
+> `NewFoo()` into a separate package and make `Foo` and it's elements
+> private. The compiler would then enforce the use of the constructor
+> to guarantee correctly defined objects.
+
+
+### Tracing
+
+Consider if the code needs to create a new
+[trace span](https://github.com/kata-containers/kata-containers/blob/main/docs/tracing.md).
+
+Ensure any new trace spans added to the code are completed.
+
+## Tests
+
+### Unit tests
+
+Where possible, code changes should be accompanied by unit tests.
+
+Consider using the standard
+[table-based approach](Unit-Test-Advice.md)
+as it encourages you to make functions small and simple, and also
+allows you to think about what types of value to test.
+
+### Other categories of test
+
+Raised a GitHub issue in the
+[`tests`](https://github.com/kata-containers/tests) repository that
+explains what sort of test is required along with as much detail as
+possible. Ensure the original issue is referenced on the `tests` issue.
+
+### Unsafe code
+
+#### Rust language specifics
+
+Minimise the use of `unsafe` blocks in Rust code and since it is
+potentially dangerous always write [unit tests][#unit-tests]
+for this code where possible.
+
+`expect()` and `unwrap()` will cause the code to panic on error.
+Prefer to return a `Result` on error rather than using these calls to
+allow the caller to deal with the error condition.
+
+The table below lists the small number of cases where use of
+`expect()` and `unwrap()` are permitted:
+
+| Area | Rationale for permitting |
+|-|-|
+| In test code (the `tests` module) | Panics will cause the test to fail, which is desirable. |
+| `lazy_static!()` | This magic macro cannot "return" a value as it runs before `main()`. |
+| `defer!()` | Similar to golang's `defer()` but doesn't allow the use of `?`. |
+| `tokio::spawn(async move {})` | Cannot currently return a `Result` from an `async move` closure. |
+| If an explicit test is performed before the `unwrap()` / `expect()` | *"Just about acceptable"*, but not ideal `[*]` |
+| `Mutex.lock()` | Almost unrecoverable if failed in the lock acquisition |
+
+
+`[*]` - There can lead to bad *future* code: consider what would
+happen if the explicit test gets dropped in the future. This is easier
+to happen if the test and the extraction of the value are two separate
+operations. In summary, this strategy can introduce an insidious
+maintenance issue.
+
+## Documentation
+
+### General requirements
+
+- All new features should be accompanied by documentation explaining:
+
+  - What the new feature does
+
+  - Why it is useful
+
+  - How to use the feature
+
+  - Any known issues or limitations
+
+    Links should be provided to GitHub issues tracking the issues
+
+- The [documentation requirements document](Documentation-Requirements.md)
+  explains how the project formats documentation.
+
+### Markdown syntax
+
+Run the
+[markdown checker](https://github.com/kata-containers/tests/tree/main/cmd/check-markdown)
+on your documentation changes.
+
+### Spell check
+
+Run the
+[spell checker](https://github.com/kata-containers/tests/tree/main/cmd/check-spelling)
+on your documentation changes.
+
+## Finally
+
+You may wish to read the documentation that the
+[Kata Review Team](https://github.com/kata-containers/community/blob/main/Rota-Process.md) use to help review PRs:
+
+- [PR review guide](https://github.com/kata-containers/community/blob/main/PR-Review-Guide.md).
+- [documentation review process](https://github.com/kata-containers/community/blob/main/Documentation-Review-Process.md).

docs/design/README.md

@@ -2,7 +2,7 @@
 
 Kata Containers design documents:
 
-- [Kata Containers architecture](architecture.md)
+- [Kata Containers architecture](architecture)
 - [API Design of Kata Containers](kata-api-design.md)
 - [Design requirements for Kata Containers](kata-design-requirements.md)
 - [VSocks](VSocks.md)

docs/design/arch-images/kata-2-metrics.drawio

@@ -1 +1 @@
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docs/design/architecture.md

@@ -1,290 +0,0 @@
-# Kata Containers Architecture
-
-## Overview
-
-This is an architectural overview of Kata Containers, based on the 2.0 release.
-
-The primary deliverable of the Kata Containers project is a CRI friendly shim. There is also a CRI friendly library API behind them.
-
-The [Kata Containers runtime](../../src/runtime)
-is compatible with the [OCI](https://github.com/opencontainers) [runtime specification](https://github.com/opencontainers/runtime-spec)
-and therefore works seamlessly with the [Kubernetes\* Container Runtime Interface (CRI)](https://github.com/kubernetes/community/blob/master/contributors/devel/sig-node/container-runtime-interface.md)
-through the [CRI-O\*](https://github.com/kubernetes-incubator/cri-o) and
-[Containerd\*](https://github.com/containerd/containerd) implementation.
-
-Kata Containers creates a QEMU\*/KVM virtual machine for pod that `kubelet` (Kubernetes) creates respectively.
-
-The [`containerd-shim-kata-v2` (shown as `shimv2` from this point onwards)](../../src/runtime/cmd/containerd-shim-kata-v2/)
-is the Kata Containers entrypoint, which
-implements the [Containerd Runtime V2 (Shim API)](https://github.com/containerd/containerd/tree/master/runtime/v2) for Kata.
-
-Before `shimv2` (as done in [Kata Containers 1.x releases](https://github.com/kata-containers/runtime/releases)), we need to create a `containerd-shim` and a [`kata-shim`](https://github.com/kata-containers/shim) for each container and the Pod sandbox itself, plus an optional [`kata-proxy`](https://github.com/kata-containers/proxy) when VSOCK is not available. With `shimv2`, Kubernetes can launch Pod and OCI compatible containers with one shim (the `shimv2`) per Pod instead of `2N+1` shims, and no standalone `kata-proxy` process even if no VSOCK is available.
-
-![Kubernetes integration with shimv2](arch-images/shimv2.svg)
-
-The container process is then spawned by
-[`kata-agent`](../../src/agent), an agent process running
-as a daemon inside the virtual machine. `kata-agent` runs a [`ttRPC`](https://github.com/containerd/ttrpc-rust) server in
-the guest using a VIRTIO serial or VSOCK interface which QEMU exposes as a socket
-file on the host. `shimv2` uses a `ttRPC` protocol to communicate with
-the agent. This protocol allows the runtime to send container management
-commands to the agent. The protocol is also used to carry the I/O streams (stdout,
-stderr, stdin) between the containers and the manage engines (e.g. CRI-O or containerd).
-
-For any given container, both the init process and all potentially executed
-commands within that container, together with their related I/O streams, need
-to go through the VSOCK interface exported by QEMU.
-
-The container workload, that is, the actual OCI bundle rootfs, is exported from the
-host to the virtual machine.  In the case where a block-based graph driver is
-configured, `virtio-scsi` will be used. In all other cases a `virtio-fs` VIRTIO mount point
-will be used. `kata-agent` uses this mount point as the root filesystem for the
-container processes.
-
-## Virtualization
-
-How Kata Containers maps container concepts to virtual machine technologies, and how this is realized in the multiple
-hypervisors and VMMs that Kata supports is described within the [virtualization documentation](./virtualization.md)
-
-## Guest assets
-
-The hypervisor will launch a virtual machine which includes a minimal guest kernel
-and a guest image.
-
-### Guest kernel
-
-The guest kernel is passed to the hypervisor and used to boot the virtual
-machine. The default kernel provided in Kata Containers is highly optimized for
-kernel boot time and minimal memory footprint, providing only those services
-required by a container workload. This is based on a very current upstream Linux
-kernel.
-
-### Guest image
-
-Kata Containers supports both an `initrd` and `rootfs` based minimal guest image.
-
-#### Root filesystem image
-
-The default packaged root filesystem image, sometimes referred to as the "mini O/S", is a
-highly optimized container bootstrap system based on [Clear Linux](https://clearlinux.org/). It provides an extremely minimal environment and
-has a highly optimized boot path.
-
-The only services running in the context of the mini O/S are the init daemon
-(`systemd`) and the [Agent](#agent). The real workload the user wishes to run
-is created using libcontainer, creating a container in the same manner that is done
-by `runc`.
-
-For example, when `ctr run -ti ubuntu date` is run:
-
-- The hypervisor will boot the mini-OS image using the guest kernel.
-- `systemd`, running inside the mini-OS context, will launch the `kata-agent` in
-  the same context.
-- The agent will create a new confined context to run the specified command in
-  (`date` in this example).
-- The agent will then execute the command (`date` in this example) inside this
-  new context, first setting the root filesystem to the expected Ubuntu\* root
-  filesystem.
-
-#### Initrd image
-
-A compressed `cpio(1)` archive, created from a rootfs which is loaded into memory and used as part of the Linux startup process. During startup, the kernel unpacks it into a special instance of a `tmpfs` that becomes the initial root filesystem.
-
-The only service running in the context of the initrd is the [Agent](#agent) as the init daemon. The real workload the user wishes to run is created using libcontainer, creating a container in the same manner that is done by `runc`.
-
-## Agent
-
-[`kata-agent`](../../src/agent) is a process running in the guest as a supervisor for managing containers and processes running within those containers.
-
-For the 2.0 release, the `kata-agent` is rewritten in the [RUST programming language](https://www.rust-lang.org/) so that we can minimize its memory footprint while keeping the memory safety of the original GO version of [`kata-agent` used in Kata Container 1.x](https://github.com/kata-containers/agent). This memory footprint reduction is pretty impressive, from tens of megabytes down to less than 100 kilobytes, enabling Kata Containers in more use cases like functional computing and edge computing.
-
-The `kata-agent` execution unit is the sandbox. A `kata-agent` sandbox is a container sandbox defined by a set of namespaces (NS, UTS, IPC and PID). `shimv2` can
-run several containers per VM to support container engines that require multiple
-containers running inside a pod.
-
-`kata-agent` communicates with the other Kata components over `ttRPC`.
-
-## Runtime
-
-`containerd-shim-kata-v2` is a [containerd runtime shimv2](https://github.com/containerd/containerd/blob/v1.4.1/runtime/v2/README.md) implementation and is responsible for handling the `runtime v2 shim APIs`, which is similar to [the OCI runtime specification](https://github.com/opencontainers/runtime-spec) but simplifies the architecture by loading the runtime once and making RPC calls to handle the various container lifecycle commands. This refinement is an improvement on the OCI specification which requires the container manager call the runtime binary multiple times, at least once for each lifecycle command.
-
-`containerd-shim-kata-v2` heavily utilizes the
-[virtcontainers package](../../src/runtime/virtcontainers/), which provides a generic, runtime-specification agnostic, hardware-virtualized containers library.
-
-### Configuration
-
-The runtime uses a TOML format configuration file called `configuration.toml`. By default this file is installed in the `/usr/share/defaults/kata-containers` directory and contains various settings such as the paths to the hypervisor, the guest kernel and the mini-OS image.
-
-The actual configuration file paths can be determined by running:
-```
-$ kata-runtime --show-default-config-paths
-```
-Most users will not need to modify the configuration file.
-
-The file is well commented and provides a few "knobs" that can be used to modify the behavior of the runtime and your chosen hypervisor.
-
-The configuration file is also used to enable runtime [debug output](../Developer-Guide.md#enable-full-debug).
-
-## Networking
-
-Containers will typically live in their own, possibly shared, networking namespace.
-At some point in a container lifecycle, container engines will set up that namespace
-to add the container to a network which is isolated from the host network, but
-which is shared between containers
-
-In order to do so, container engines will usually add one end of a virtual
-ethernet (`veth`) pair into the container networking namespace. The other end of
-the `veth` pair is added to the host networking namespace.
-
-This is a very namespace-centric approach as many hypervisors/VMMs cannot handle `veth` 
-interfaces. Typically, `TAP` interfaces are created for VM connectivity.
-
-To overcome incompatibility between typical container engines expectations
-and virtual machines, Kata Containers networking transparently connects `veth`
-interfaces with `TAP` ones using Traffic Control:
-
-![Kata Containers networking](arch-images/network.png)
-
-With a TC filter in place, a redirection is created between the container network and the
-virtual machine. As an example, the CNI may create a device, `eth0`, in the container's network
-namespace, which is a VETH device. Kata Containers will create a tap device for the VM, `tap0_kata`,
-and setup a TC redirection filter to mirror traffic from `eth0`'s ingress to `tap0_kata`'s egress,
-and a second to mirror traffic from `tap0_kata`'s ingress to `eth0`'s egress.
-
-Kata Containers maintains support for MACVTAP, which was an earlier implementation used in Kata. TC-filter
-is the default because it allows for simpler configuration, better CNI plugin compatibility, and performance
-on par with MACVTAP.
-
-Kata Containers has deprecated support for bridge due to lacking performance relative to TC-filter and MACVTAP.
-
- Kata Containers supports both
-[CNM](https://github.com/docker/libnetwork/blob/master/docs/design.md#the-container-network-model)
-and [CNI](https://github.com/containernetworking/cni) for networking management.
-
-### Network Hotplug
-
-Kata Containers has developed a set of network sub-commands and APIs to add, list and
-remove a guest network endpoint and to manipulate the guest route table.
-
-The following diagram illustrates the Kata Containers network hotplug workflow.
-
-![Network Hotplug](arch-images/kata-containers-network-hotplug.png)
-
-## Storage
-Container workloads are shared with the virtualized environment through [virtio-fs](https://virtio-fs.gitlab.io/).
-
-The [devicemapper `snapshotter`](https://github.com/containerd/containerd/tree/master/snapshots/devmapper) is a special case. The `snapshotter` uses dedicated block devices rather than formatted filesystems, and operates at the block level rather than the file level. This knowledge is used to directly use the underlying block device instead of the overlay file system for the container root file system. The block device maps to the top read-write layer for the overlay. This approach gives much better I/O performance compared to using `virtio-fs` to share the container file system.
-
-Kata Containers has the ability to hotplug and remove block devices, which makes it possible to use block devices for containers started after the VM has been launched.
-
-Users can check to see if the container uses the devicemapper block device as its rootfs by calling `mount(8)` within the container.  If the devicemapper block device
-is used, `/` will be mounted on `/dev/vda`.  Users can disable direct mounting of the underlying block device through the runtime configuration.
-
-## Kubernetes support
-
-[Kubernetes\*](https://github.com/kubernetes/kubernetes/) is a popular open source
-container orchestration engine. In Kubernetes, a set of containers sharing resources
-such as networking, storage, mount, PID, etc. is called a
-[Pod](https://kubernetes.io/docs/user-guide/pods/).
-A node can have multiple pods, but at a minimum, a node within a Kubernetes cluster
-only needs to run a container runtime and a container agent (called a
-[Kubelet](https://kubernetes.io/docs/admin/kubelet/)).
-
-A Kubernetes cluster runs a control plane where a scheduler (typically running on a
-dedicated master node) calls into a compute Kubelet. This Kubelet instance is
-responsible for managing the lifecycle of pods within the nodes and eventually relies
-on a container runtime to handle execution. The Kubelet architecture decouples
-lifecycle management from container execution through the dedicated
-`gRPC` based [Container Runtime Interface (CRI)](https://github.com/kubernetes/community/blob/master/contributors/design-proposals/node/container-runtime-interface-v1.md).
-
-In other words, a Kubelet is a CRI client and expects a CRI implementation to
-handle the server side of the interface.
-[CRI-O\*](https://github.com/kubernetes-incubator/cri-o) and [Containerd\*](https://github.com/containerd/containerd/) are CRI implementations that rely on [OCI](https://github.com/opencontainers/runtime-spec)
-compatible runtimes for managing container instances.
-
-Kata Containers is an officially supported CRI-O and Containerd runtime. Refer to the following guides on how to set up Kata Containers with Kubernetes:
-
-- [How to use Kata Containers and Containerd](../how-to/containerd-kata.md)
-- [Run Kata Containers with Kubernetes](../how-to/run-kata-with-k8s.md)
-
-####  OCI annotations
-
-In order for the Kata Containers runtime (or any virtual machine  based OCI compatible
-runtime) to be able to understand if it needs to create a full virtual machine or if it
-has to create a new container inside an existing pod's virtual machine, CRI-O adds
-specific annotations to the OCI configuration file (`config.json`) which is passed to
-the OCI compatible runtime.
-
-Before calling its runtime, CRI-O will always add a `io.kubernetes.cri-o.ContainerType`
-annotation to the `config.json` configuration file it produces from the Kubelet CRI
-request. The `io.kubernetes.cri-o.ContainerType` annotation can either be set to `sandbox`
-or `container`. Kata Containers will then use this annotation to decide if it needs to
-respectively create a virtual machine or a container inside a virtual machine associated
-with a Kubernetes pod:
-
-```Go
-	containerType, err := ociSpec.ContainerType()
-	if err != nil {
-		return err
-	}
-
-	handleFactory(ctx, runtimeConfig)
-
-	disableOutput := noNeedForOutput(detach, ociSpec.Process.Terminal)
-
-	var process vc.Process
-	switch containerType {
-	case vc.PodSandbox:
-		process, err = createSandbox(ctx, ociSpec, runtimeConfig, containerID, bundlePath, console, disableOutput, systemdCgroup)
-		if err != nil {
-			return err
-		}
-	case vc.PodContainer:
-		process, err = createContainer(ctx, ociSpec, containerID, bundlePath, console, disableOutput)
-		if err != nil {
-			return err
-		}
-	}
-
-```
-
-#### Mixing VM based and namespace based runtimes
-
-> **Note:** Since Kubernetes 1.12, the [`Kubernetes RuntimeClass`](https://kubernetes.io/docs/concepts/containers/runtime-class/)
-> has been supported and the user can specify runtime without the non-standardized annotations.
-
-With `RuntimeClass`, users can define Kata Containers as a `RuntimeClass` and then explicitly specify that a pod being created as a Kata Containers pod. For details, please refer to [How to use Kata Containers and Containerd](../../docs/how-to/containerd-kata.md).
-
-
-# Appendices
-
-## DAX
-
-Kata Containers utilizes the Linux kernel DAX [(Direct Access filesystem)](https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/tree/Documentation/filesystems/dax.rst?h=v5.14)
-feature to efficiently map some host-side files into the guest VM space.
-In particular, Kata Containers uses the QEMU NVDIMM feature to provide a
-memory-mapped virtual device that can be used to DAX map the virtual machine's
-root filesystem into the guest memory address space.
-
-Mapping files using DAX provides a number of benefits over more traditional VM
-file and device mapping mechanisms:
-
-- Mapping as a direct access devices allows the guest to directly access
-  the host memory pages (such as via Execute In Place (XIP)), bypassing the guest
-  page cache. This provides both time and space optimizations.
-- Mapping as a direct access device inside the VM allows pages from the
-  host to be demand loaded using page faults, rather than having to make requests
-  via a virtualized device (causing expensive VM exits/hypercalls), thus providing
-  a speed optimization.
-- Utilizing `MAP_SHARED` shared memory on the host allows the host to efficiently
-  share pages.
-
-Kata Containers uses the following steps to set up the DAX mappings:
-1. QEMU is configured with an NVDIMM memory device, with a memory file
-  backend to map in the host-side file into the virtual NVDIMM space.
-2. The guest kernel command line mounts this NVDIMM device with the DAX
-  feature enabled, allowing direct page mapping and access, thus bypassing the
-  guest page cache.
-
-![DAX](arch-images/DAX.png)
-
-Information on the use of NVDIMM via QEMU is available in the [QEMU source code](http://git.qemu-project.org/?p=qemu.git;a=blob;f=docs/nvdimm.txt;hb=HEAD)

docs/design/architecture/README.md

@@ -0,0 +1,477 @@
+# Kata Containers Architecture
+
+## Overview
+
+Kata Containers is an open source community working to build a secure
+container [runtime](#runtime) with lightweight virtual machines (VM's)
+that feel and perform like standard Linux containers, but provide
+stronger [workload](#workload) isolation using hardware
+[virtualization](#virtualization) technology as a second layer of
+defence.
+
+Kata Containers runs on [multiple architectures](../../../src/runtime/README.md#platform-support)
+and supports [multiple hypervisors](../../hypervisors.md).
+
+This document is a summary of the Kata Containers architecture.
+
+## Background knowledge
+
+This document assumes the reader understands a number of concepts
+related to containers and file systems. The
+[background](background.md) document explains these concepts.
+
+## Example command
+
+This document makes use of a particular [example
+command](example-command.md) throughout the text to illustrate certain
+concepts.
+
+## Virtualization
+
+For details on how Kata Containers maps container concepts to VM
+technologies, and how this is realized in the multiple hypervisors and
+VMMs that Kata supports see the
+[virtualization documentation](../virtualization.md).
+
+## Compatibility
+
+The [Kata Containers runtime](../../../src/runtime) is compatible with
+the [OCI](https://github.com/opencontainers)
+[runtime specification](https://github.com/opencontainers/runtime-spec)
+and therefore works seamlessly with the
+[Kubernetes Container Runtime Interface (CRI)](https://github.com/kubernetes/community/blob/master/contributors/devel/sig-node/container-runtime-interface.md)
+through the [CRI-O](https://github.com/kubernetes-incubator/cri-o)
+and [containerd](https://github.com/containerd/containerd)
+implementations.
+
+Kata Containers provides a ["shimv2"](#shim-v2-architecture) compatible runtime.
+
+## Shim v2 architecture
+
+The Kata Containers runtime is shim v2 ("shimv2") compatible. This
+section explains what this means.
+
+> **Note:**
+>
+> For a comparison with the Kata 1.x architecture, see
+> [the architectural history document](history.md).
+
+The
+[containerd runtime shimv2 architecture](https://github.com/containerd/containerd/tree/main/runtime/v2)
+or _shim API_ architecture resolves the issues with the old
+architecture by defining a set of shimv2 APIs that a compatible
+runtime implementation must supply. Rather than calling the runtime
+binary multiple times for each new container, the shimv2 architecture
+runs a single instance of the runtime binary (for any number of
+containers). This improves performance and resolves the state handling
+issue.
+
+The shimv2 API is similar to the
+[OCI runtime](https://github.com/opencontainers/runtime-spec)
+API in terms of the way the container lifecycle is split into
+different verbs. Rather than calling the runtime multiple times, the
+container manager creates a socket and passes it to the shimv2
+runtime. The socket is a bi-directional communication channel that
+uses a gRPC based protocol to allow the container manager to send API
+calls to the runtime, which returns the result to the container
+manager using the same channel.
+
+The shimv2 architecture allows running several containers per VM to
+support container engines that require multiple containers running
+inside a pod.
+
+With the new architecture [Kubernetes](kubernetes.md) can
+launch both Pod and OCI compatible containers with a single
+[runtime](#runtime) shim per Pod, rather than `2N+1` shims. No stand
+alone `kata-proxy` process is required, even if VSOCK is not
+available.
+
+## Workload
+
+The workload is the command the user requested to run in the
+container and is specified in the [OCI bundle](background.md#oci-bundle)'s
+configuration file.
+
+In our [example](example-command.md), the workload is the `sh(1)` command.
+
+### Workload root filesystem
+
+For details of how the [runtime](#runtime) makes the
+[container image](background.md#container-image) chosen by the user available to
+the workload process, see the
+[Container creation](#container-creation) and [storage](#storage) sections.
+
+Note that the workload is isolated from the [guest VM](#environments) environment by its
+surrounding [container environment](#environments). The guest VM
+environment where the container runs in is also isolated from the _outer_
+[host environment](#environments) where the container manager runs.
+
+## System overview
+
+### Environments
+
+The following terminology is used to describe the different or
+environments (or contexts) various processes run in. It is necessary
+to study this table closely to make sense of what follows:
+
+| Type | Name | Virtualized | Containerized | rootfs | Rootfs device type | Mount type | Description |
+|-|-|-|-|-|-|-|-|
+| Host | Host | no `[1]` | no | Host specific | Host specific | Host specific | The environment provided by a standard, physical non virtualized system. |
+| VM root | Guest VM | yes | no | rootfs inside the [guest image](guest-assets.md#guest-image) | Hypervisor specific `[2]` | `ext4` | The first (or top) level VM environment created on a host system. |
+| VM container root | Container | yes | yes | rootfs type requested by user ([`ubuntu` in the example](example-command.md)) | `kataShared` | [virtio FS](storage.md#virtio-fs) | The first (or top) level container environment created inside the VM. Based on the [OCI bundle](background.md#oci-bundle). |
+
+**Key:**
+
+- `[1]`: For simplicity, this document assumes the host environment
+  runs on physical hardware.
+
+- `[2]`: See the [DAX](#dax) section.
+
+> **Notes:**
+>
+> - The word "root" is used to mean _top level_ here in a similar
+>   manner to the term [rootfs](background.md#root-filesystem).
+>
+> - The term "first level" prefix used above is important since it implies
+>   that it is possible to create multi level systems. However, they do
+>   not form part of a standard Kata Containers environment so will not
+>   be considered in this document.
+
+The reasons for containerizing the [workload](#workload) inside the VM
+are:
+
+- Isolates the workload entirely from the VM environment.
+- Provides better isolation between containers in a [pod](kubernetes.md).
+- Allows the workload to be managed and monitored through its cgroup
+  confinement.
+
+### Container creation
+
+The steps below show at a high level how a Kata Containers container is
+created using the containerd container manager:
+
+1. The user requests the creation of a container by running a command
+   like the [example command](example-command.md).
+1. The container manager daemon runs a single instance of the Kata
+   [runtime](#runtime).
+1. The Kata runtime loads its [configuration file](#configuration).
+1. The container manager calls a set of shimv2 API functions on the runtime.
+1. The Kata runtime launches the configured [hypervisor](#hypervisor).
+1. The hypervisor creates and starts (_boots_) a VM using the
+   [guest assets](guest-assets.md#guest-assets):
+
+   - The hypervisor [DAX](#dax) shares the
+     [guest image](guest-assets.md#guest-image)
+     into the VM to become the VM [rootfs](background.md#root-filesystem) (mounted on a `/dev/pmem*` device),
+     which is known as the [VM root environment](#environments).
+   - The hypervisor mounts the [OCI bundle](background.md#oci-bundle), using [virtio FS](storage.md#virtio-fs),
+     into a container specific directory inside the VM's rootfs.
+
+     This container specific directory will become the
+     [container rootfs](#environments), known as the
+     [container environment](#environments).
+
+1. The [agent](#agent) is started as part of the VM boot.
+
+1. The runtime calls the agent's `CreateSandbox` API to request the
+   agent create a container:
+
+   1. The agent creates a [container environment](#environments)
+      in the container specific directory that contains the [container rootfs](#environments).
+
+      The container environment hosts the [workload](#workload) in the
+      [container rootfs](#environments) directory.
+
+   1. The agent spawns the workload inside the container environment.
+
+   > **Notes:**
+   >
+   > - The container environment created by the agent is equivalent to
+   >   a container environment created by the
+   >   [`runc`](https://github.com/opencontainers/runc) OCI runtime;
+   >   Linux cgroups and namespaces are created inside the VM by the
+   >   [guest kernel](guest-assets.md#guest-kernel) to isolate the
+   >   workload from the VM environment the container is created in.
+   >   See the [Environments](#environments) section for an
+   >   explanation of why this is done.
+   >
+   > - See the [guest image](guest-assets.md#guest-image) section for
+   >   details of exactly how the agent is started.
+
+1. The container manager returns control of the container to the
+   user running the `ctr` command.
+
+> **Note:**
+>
+> At this point, the container is running and:
+>
+> - The [workload](#workload) process ([`sh(1)` in the example](example-command.md))
+>   is running in the [container environment](#environments).
+> - The user is now able to interact with the workload
+>   (using the [`ctr` command in the example](example-command.md)).
+> - The [agent](#agent), running inside the VM is monitoring the
+>   [workload](#workload) process.
+> - The [runtime](#runtime) is waiting for the agent's `WaitProcess` API
+>   call to complete.
+
+Further details of these steps are provided in the sections below.
+
+### Container shutdown
+
+There are two possible ways for the container environment to be
+terminated:
+
+- When the [workload](#workload) exits.
+
+  This is the standard, or _graceful_ shutdown method.
+
+- When the container manager forces the container to be deleted.
+
+#### Workload exit
+
+The [agent](#agent) will detect when the [workload](#workload) process
+exits, capture its exit status (see `wait(2)`) and return that value
+to the [runtime](#runtime) by specifying it as the response to the
+`WaitProcess` agent API call made by the [runtime](#runtime).
+
+The runtime then passes the value back to the container manager by the
+`Wait` [shimv2 API](#shim-v2-architecture) call.
+
+Once the workload has fully exited, the VM is no longer needed and the
+runtime cleans up the environment (which includes terminating the
+[hypervisor](#hypervisor) process).
+
+> **Note:**
+>
+> When [agent tracing is enabled](../../tracing.md#agent-shutdown-behaviour),
+> the shutdown behaviour is different.
+
+#### Container manager requested shutdown
+
+If the container manager requests the container be deleted, the
+[runtime](#runtime) will signal the agent by sending it a
+`DestroySandbox` [ttRPC API](../../../src/agent/protocols/protos/agent.proto) request.
+
+## Guest assets
+
+The guest assets comprise a guest image and a guest kernel that are
+used by the [hypervisor](#hypervisor).
+
+See the [guest assets](guest-assets.md) document for further
+information.
+
+## Hypervisor
+
+The [hypervisor](../../hypervisors.md) specified in the
+[configuration file](#configuration) creates a VM to host the
+[agent](#agent) and the [workload](#workload) inside the
+[container environment](#environments).
+
+> **Note:**
+>
+> The hypervisor process runs inside an environment slightly different
+> to the host environment:
+>
+> - It is run in a different cgroup environment to the host.
+> - It is given a separate network namespace from the host.
+> - If the [OCI configuration specifies a SELinux label](https://github.com/opencontainers/runtime-spec/blob/main/config.md#linux-process),
+>   the hypervisor process will run with that label (*not* the workload running inside the hypervisor's VM).
+
+## Agent
+
+The Kata Containers agent ([`kata-agent`](../../../src/agent)), written
+in the [Rust programming language](https://www.rust-lang.org), is a
+long running process that runs inside the VM. It acts as the
+supervisor for managing the containers and the [workload](#workload)
+running within those containers. Only a single agent process is run
+for each VM created.
+
+### Agent communications protocol
+
+The agent communicates with the other Kata components (primarily the
+[runtime](#runtime)) using a
+[`ttRPC`](https://github.com/containerd/ttrpc-rust) based
+[protocol](../../../src/agent/protocols/protos).
+
+> **Note:**
+>
+> If you wish to learn more about this protocol, a practical way to do
+> so is to experiment with the
+> [agent control tool](#agent-control-tool) on a test system.
+> This tool is for test and development purposes only and can send
+> arbitrary ttRPC agent API commands to the [agent](#agent).
+
+## Runtime
+
+The Kata Containers runtime (the [`containerd-shim-kata-v2`](../../../src/runtime/cmd/containerd-shim-kata-v2
+) binary) is a [shimv2](#shim-v2-architecture) compatible runtime.
+
+> **Note:**
+>
+> The Kata Containers runtime is sometimes referred to as the Kata
+> _shim_. Both terms are correct since the `containerd-shim-kata-v2`
+> is a container runtime, and that runtime implements the containerd
+> shim v2 API.
+
+The runtime makes heavy use of the [`virtcontainers`
+package](../../../src/runtime/virtcontainers), which provides a generic,
+runtime-specification agnostic, hardware-virtualized containers
+library.
+
+The runtime is responsible for starting the [hypervisor](#hypervisor)
+and it's VM, and communicating with the [agent](#agent) using a
+[ttRPC based protocol](#agent-communications-protocol) over a VSOCK
+socket that provides a communications link between the VM and the
+host. 
+
+This protocol allows the runtime to send container management commands
+to the agent. The protocol is also used to carry the standard I/O
+streams (`stdout`, `stderr`, `stdin`) between the containers and
+container managers (such as CRI-O or containerd).
+
+## Utility program
+
+The `kata-runtime` binary is a utility program that provides
+administrative commands to manipulate and query a Kata Containers
+installation.
+
+> **Note:**
+>
+> In Kata 1.x, this program also acted as the main
+> [runtime](#runtime), but this is no longer required due to the
+> improved shimv2 architecture.
+
+### exec command
+
+The `exec` command allows an administrator or developer to enter the
+[VM root environment](#environments) which is not accessible by the container
+[workload](#workload).
+
+See [the developer guide](../../Developer-Guide.md#connect-to-debug-console) for further details.
+
+### Configuration
+
+See the [configuration file details](../../../src/runtime/README.md#configuration).
+
+The configuration file is also used to enable runtime [debug output](../../Developer-Guide.md#enable-full-debug).
+
+## Process overview
+
+The table below shows an example of the main processes running in the
+different [environments](#environments) when a Kata Container is
+created with containerd using our [example command](example-command.md):
+
+| Description | Host | VM root environment | VM container environment |
+|-|-|-|-|
+| Container manager | `containerd` | |
+| Kata Containers | [runtime](#runtime), [`virtiofsd`](storage.md#virtio-fs), [hypervisor](#hypervisor) | [agent](#agent) |
+| User [workload](#workload) | | | [`ubuntu sh`](example-command.md) |
+
+## Networking
+
+See the [networking document](networking.md).
+
+## Storage
+
+See the [storage document](storage.md).
+
+## Kubernetes support
+
+See the [Kubernetes document](kubernetes.md).
+
+####  OCI annotations
+
+In order for the Kata Containers [runtime](#runtime) (or any VM based OCI compatible
+runtime) to be able to understand if it needs to create a full VM or if it
+has to create a new container inside an existing pod's VM, CRI-O adds
+specific annotations to the OCI configuration file (`config.json`) which is passed to
+the OCI compatible runtime.
+
+Before calling its runtime, CRI-O will always add a `io.kubernetes.cri-o.ContainerType`
+annotation to the `config.json` configuration file it produces from the Kubelet CRI
+request. The `io.kubernetes.cri-o.ContainerType` annotation can either be set to `sandbox`
+or `container`. Kata Containers will then use this annotation to decide if it needs to
+respectively create a virtual machine or a container inside a virtual machine associated
+with a Kubernetes pod:
+
+| Annotation value | Kata VM created? | Kata container created? |
+|-|-|-|
+| `sandbox` | yes | yes (inside new VM) |
+| `container`| no | yes (in existing VM) |
+
+#### Mixing VM based and namespace based runtimes
+
+> **Note:** Since Kubernetes 1.12, the [`Kubernetes RuntimeClass`](https://kubernetes.io/docs/concepts/containers/runtime-class/)
+> has been supported and the user can specify runtime without the non-standardized annotations.
+
+With `RuntimeClass`, users can define Kata Containers as a
+`RuntimeClass` and then explicitly specify that a pod must be created
+as a Kata Containers pod. For details, please refer to [How to use
+Kata Containers and containerd](../../../docs/how-to/containerd-kata.md).
+
+## Tracing
+
+The [tracing document](../../tracing.md) provides details on the tracing
+architecture.
+
+# Appendices
+
+## DAX
+
+Kata Containers utilizes the Linux kernel DAX
+[(Direct Access filesystem)](https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/tree/Documentation/filesystems/dax.rst?h=v5.14)
+feature to efficiently map the [guest image](guest-assets.md#guest-image) in the
+[host environment](#environments) into the
+[guest VM environment](#environments) to become the VM's
+[rootfs](background.md#root-filesystem).
+
+If the [configured](#configuration) [hypervisor](#hypervisor) is set
+to either QEMU or Cloud Hypervisor, DAX is used with the feature shown
+in the table below:
+
+| Hypervisor | Feature used | rootfs device type |
+|-|-|-|
+| Cloud Hypervisor (CH) | `dax` `FsConfig` configuration option | PMEM (emulated Persistent Memory device) |
+| QEMU | NVDIMM memory device with a memory file backend | NVDIMM (emulated Non-Volatile Dual In-line Memory Module device) |
+
+The features in the table above are equivalent in that they provide a memory-mapped
+virtual device which is used to DAX map the VM's
+[rootfs](background.md#root-filesystem) into the [VM guest](#environments) memory
+address space.
+
+The VM is then booted, specifying the `root=` kernel parameter to make
+the [guest kernel](guest-assets.md#guest-kernel) use the appropriate emulated device
+as its rootfs.
+
+### DAX advantages
+
+Mapping files using [DAX](#dax) provides a number of benefits over
+more traditional VM file and device mapping mechanisms:
+
+- Mapping as a direct access device allows the guest to directly
+  access the host memory pages (such as via Execute In Place (XIP)),
+  bypassing the [guest kernel](guest-assets.md#guest-kernel)'s page cache. This
+  zero copy provides both time and space optimizations.
+
+- Mapping as a direct access device inside the VM allows pages from the
+  host to be demand loaded using page faults, rather than having to make requests
+  via a virtualized device (causing expensive VM exits/hypercalls), thus providing
+  a speed optimization.
+
+- Utilizing `mmap(2)`'s `MAP_SHARED` shared memory option on the host
+  allows the host to efficiently share pages.
+
+![DAX](../arch-images/DAX.png)
+
+For further details of the use of NVDIMM with QEMU, see the [QEMU
+project documentation](https://www.qemu.org).
+
+## Agent control tool
+
+The [agent control tool](../../../src/tools/agent-ctl) is a test and
+development tool that can be used to learn more about a Kata
+Containers system.
+
+## Terminology
+
+See the [project glossary](../../../Glossary.md).

docs/design/architecture/background.md

@@ -0,0 +1,81 @@
+# Kata Containers architecture background knowledge
+
+The following sections explain some of the background concepts
+required to understand the [architecture document](README.md).
+
+## Root filesystem
+
+This document uses the term _rootfs_ to refer to a root filesystem
+which is mounted as the top-level directory ("`/`") and often referred
+to as _slash_.
+
+It is important to understand this term since the overall system uses
+multiple different rootfs's (as explained in the
+[Environments](README.md#environments) section.
+
+## Container image
+
+In the [example command](example-command.md) the user has specified the
+type of container they wish to run via the container image name:
+`ubuntu`. This image name corresponds to a _container image_ that can
+be used to create a container with an Ubuntu Linux environment. Hence,
+in our [example](example-command.md), the `sh(1)` command will be run
+inside a container which has an Ubuntu rootfs.
+
+> **Note:**
+>
+> The term _container image_ is confusing since the image in question
+> is **not** a container: it is simply a set of files (_an image_)
+> that can be used to _create_ a container. The term _container
+> template_ would be more accurate but the term _container image_ is
+> commonly used so this document uses the standard term.
+
+For the purposes of this document, the most important part of the
+[example command line](example-command.md) is the container image the
+user has requested. Normally, the container manager will _pull_
+(download) a container image from a remote site and store a copy
+locally. This local container image is used by the container manager
+to create an [OCI bundle](#oci-bundle) which will form the environment
+the container will run in. After creating the OCI bundle, the
+container manager launches a [runtime](README.md#runtime) which will create the
+container using the provided OCI bundle.
+
+## OCI bundle
+
+To understand what follows, it is important to know at a high level
+how an OCI ([Open Containers Initiative](https://opencontainers.org)) compatible container is created.
+
+An OCI compatible container is created by taking a
+[container image](#container-image) and converting the embedded rootfs
+into an
+[OCI rootfs bundle](https://github.com/opencontainers/runtime-spec/blob/main/bundle.md),
+or more simply, an _OCI bundle_.
+
+An OCI bundle is a `tar(1)` archive normally created by a container
+manager which is passed to an OCI [runtime](README.md#runtime) which converts
+it into a full container rootfs. The bundle contains two assets:
+
+- A container image [rootfs](#root-filesystem)
+
+  This is simply a directory of files that will be used to represent
+  the rootfs for the container.
+
+  For the [example command](example-command.md), the directory will
+  contain the files necessary to create a minimal Ubuntu root
+  filesystem.
+
+- An [OCI configuration file](https://github.com/opencontainers/runtime-spec/blob/main/config.md)
+
+  This is a JSON file called `config.json`.
+
+  The container manager will create this file so that:
+
+  - The `root.path` value is set to the full path of the specified
+    container rootfs.
+
+    In [the example](example-command.md) this value will be `ubuntu`.
+
+  - The `process.args` array specifies the list of commands the user
+    wishes to run. This is known as the [workload](README.md#workload).
+
+    In [the example](example-command.md) the workload is `sh(1)`.

docs/design/architecture/example-command.md

@@ -0,0 +1,30 @@
+# Example command
+
+The following containerd command creates a container. It is referred
+to throughout the architecture document to help explain various points:
+
+```bash
+$ sudo ctr run --runtime "io.containerd.kata.v2" --rm -t "quay.io/libpod/ubuntu:latest" foo sh
+```
+
+This command requests that containerd:
+
+- Create a container (`ctr run`).
+- Use the Kata [shimv2](README.md#shim-v2-architecture) runtime (`--runtime "io.containerd.kata.v2"`).
+- Delete the container when it [exits](README.md#workload-exit) (`--rm`).
+- Attach the container to the user's terminal (`-t`).
+- Use the Ubuntu Linux [container image](background.md#container-image)
+  to create the container [rootfs](background.md#root-filesystem) that will become
+  the [container environment](README.md#environments)
+  (`quay.io/libpod/ubuntu:latest`).
+- Create the container with the name "`foo`".
+- Run the `sh(1)` command in the Ubuntu rootfs based container
+  environment.
+
+  The command specified here is referred to as the [workload](README.md#workload).
+
+> **Note:**
+>
+> For the purposes of this document and to keep explanations
+> simpler, we assume the user is running this command in the
+> [host environment](README.md#environments).

docs/design/architecture/guest-assets.md

@@ -0,0 +1,152 @@
+# Guest assets
+
+Kata Containers creates a VM in which to run one or more containers.
+It does this by launching a [hypervisor](README.md#hypervisor) to
+create the VM. The hypervisor needs two assets for this task: a Linux
+kernel and a small root filesystem image to boot the VM.
+
+## Guest kernel
+
+The [guest kernel](../../../tools/packaging/kernel)
+is passed to the hypervisor and used to boot the VM.
+The default kernel provided in Kata Containers is highly optimized for
+kernel boot time and minimal memory footprint, providing only those
+services required by a container workload. It is based on the latest
+Linux LTS (Long Term Support) [kernel](https://www.kernel.org).
+
+## Guest image
+
+The hypervisor uses an image file which provides a minimal root
+filesystem used by the guest kernel to boot the VM and host the Kata
+Container. Kata Containers supports both initrd and rootfs based
+minimal guest images. The [default packages](../../install/) provide both
+an image and an initrd, both of which are created using the
+[`osbuilder`](../../../tools/osbuilder) tool.
+
+> **Notes:**
+>
+> - Although initrd and rootfs based images are supported, not all
+>   [hypervisors](README.md#hypervisor) support both types of image.
+>
+> - The guest image is *unrelated* to the image used in a container
+>   workload.
+>
+>   For example, if a user creates a container that runs a shell in a
+>   BusyBox image, they will run that shell in a BusyBox environment.
+>   However, the guest image running inside the VM that is used to
+>   *host* that BusyBox image could be running Clear Linux, Ubuntu,
+>   Fedora or any other distribution potentially.
+>
+>   The `osbuilder` tool provides
+>   [configurations for various common Linux distributions](../../../tools/osbuilder/rootfs-builder)
+>   which can be built into either initrd or rootfs guest images.
+>
+> - If you are using a [packaged version of Kata
+>   Containers](../../install), you can see image details by running the
+>   [`kata-collect-data.sh`](../../../src/runtime/data/kata-collect-data.sh.in)
+>   script as `root` and looking at the "Image details" section of the
+>   output.
+
+#### Root filesystem image
+
+The default packaged rootfs image, sometimes referred to as the _mini
+O/S_, is a highly optimized container bootstrap system.
+
+If this image type is [configured](README.md#configuration), when the
+user runs the [example command](example-command.md):
+
+- The [runtime](README.md#runtime) will launch the configured [hypervisor](README.md#hypervisor).
+- The hypervisor will boot the mini-OS image using the [guest kernel](#guest-kernel).
+- The kernel will start the init daemon as PID 1 (`systemd`) inside the VM root environment.
+- `systemd`, running inside the mini-OS context, will launch the [agent](README.md#agent)
+  in the root context of the VM.
+- The agent will create a new container environment, setting its root
+  filesystem to that requested by the user (Ubuntu in [the example](example-command.md)).
+- The agent will then execute the command (`sh(1)` in [the example](example-command.md))
+  inside the new container.
+
+The table below summarises the default mini O/S showing the
+environments that are created, the services running in those
+environments (for all platforms) and the root filesystem used by
+each service:
+
+| Process | Environment | systemd service? | rootfs | User accessible | Notes |
+|-|-|-|-|-|-|
+| systemd | VM root | n/a | [VM guest image](#guest-image)| [debug console][debug-console] | The init daemon, running as PID 1 |
+| [Agent](README.md#agent) | VM root | yes | [VM guest image](#guest-image)| [debug console][debug-console] | Runs as a systemd service |
+| `chronyd` | VM root | yes | [VM guest image](#guest-image)| [debug console][debug-console] | Used to synchronise the time with the host |
+| container workload (`sh(1)` in [the example](example-command.md)) | VM container | no | User specified (Ubuntu in [the example](example-command.md)) | [exec command](README.md#exec-command) | Managed by the agent |
+
+See also the [process overview](README.md#process-overview).
+
+> **Notes:**
+>
+> - The "User accessible" column shows how an administrator can access
+>   the environment.
+>
+> - The container workload is running inside a full container
+>   environment which itself is running within a VM environment.
+>
+> - See the [configuration files for the `osbuilder` tool](../../../tools/osbuilder/rootfs-builder)
+>   for details of the default distribution for platforms other than
+>   Intel x86_64.
+
+#### Initrd image
+
+The initrd image is a compressed `cpio(1)` archive, created from a
+rootfs which is loaded into memory and used as part of the Linux
+startup process. During startup, the kernel unpacks it into a special
+instance of a `tmpfs` mount that becomes the initial root filesystem.
+
+If this image type is [configured](README.md#configuration), when the user runs
+the [example command](example-command.md):
+
+- The [runtime](README.md#runtime) will launch the configured [hypervisor](README.md#hypervisor).
+- The hypervisor will boot the mini-OS image using the [guest kernel](#guest-kernel).
+- The kernel will start the init daemon as PID 1 (the
+  [agent](README.md#agent))
+  inside the VM root environment.
+- The [agent](README.md#agent) will create a new container environment, setting its root
+  filesystem to that requested by the user (`ubuntu` in
+  [the example](example-command.md)).
+- The agent will then execute the command (`sh(1)` in [the example](example-command.md))
+  inside the new container.
+
+The table below summarises the default mini O/S showing the environments that are created,
+the processes running in those environments (for all platforms) and
+the root filesystem used by each service:
+
+| Process | Environment | rootfs | User accessible | Notes |
+|-|-|-|-|-|
+| [Agent](README.md#agent) | VM root | [VM guest image](#guest-image) | [debug console][debug-console] | Runs as the init daemon (PID 1) |
+| container workload | VM container | User specified (Ubuntu in this example) | [exec command](README.md#exec-command) | Managed by the agent |
+
+> **Notes:**
+>
+> - The "User accessible" column shows how an administrator can access
+>   the environment.
+>
+> - It is possible to use a standard init daemon such as systemd with
+>   an initrd image if this is desirable.
+
+See also the [process overview](README.md#process-overview).
+
+#### Image summary
+
+| Image type | Default distro | Init daemon | Reason | Notes |
+|-|-|-|-|-|
+| [image](background.md#root-filesystem-image) | [Clear Linux](https://clearlinux.org) (for x86_64 systems)| systemd | Minimal and highly optimized | systemd offers flexibility |
+| [initrd](#initrd-image) | [Alpine Linux](https://alpinelinux.org) | Kata [agent](README.md#agent) (as no systemd support) | Security hardened and tiny C library |
+
+See also:
+
+- The [osbuilder](../../../tools/osbuilder) tool
+
+  This is used to build all default image types.
+
+- The [versions database](../../../versions.yaml)
+
+  The `default-image-name` and `default-initrd-name` options specify
+  the default distributions for each image type.
+
+[debug-console]: ../../Developer-Guide.md#connect-to-debug-console

docs/design/architecture/history.md

@@ -0,0 +1,41 @@
+# History
+
+## Kata 1.x architecture
+
+In the old [Kata 1.x architecture](https://github.com/kata-containers/documentation/blob/master/design/architecture.md),
+the Kata [runtime](README.md#runtime) was an executable called `kata-runtime`.
+The container manager called this executable multiple times when
+creating each container. Each time the runtime was called a different
+OCI command-line verb was provided. This architecture was simple, but
+not well suited to creating VM based containers due to the issue of
+handling state between calls. Additionally, the architecture suffered
+from performance issues related to continually having to spawn new
+instances of the runtime binary, and
+[Kata shim](https://github.com/kata-containers/shim) and
+[Kata proxy](https://github.com/kata-containers/proxy) processes for systems
+that did not provide VSOCK.
+
+## Kata 2.x architecture
+
+See the ["shimv2"](README.md#shim-v2-architecture) section of the
+architecture document.
+
+## Architectural comparison
+
+| Kata version | Kata Runtime process calls | Kata shim processes | Kata proxy processes (if no VSOCK) |
+|-|-|-|-|
+| 1.x | multiple per container | 1 per container connection | 1 |
+| 2.x | 1 per VM (hosting any number of containers) | 0 | 0 |
+
+> **Notes:**
+>
+> - A single VM can host one or more containers.
+>
+> - The "Kata shim processes" column refers to the old
+>   [Kata shim](https://github.com/kata-containers/shim) (`kata-shim` binary),
+>   *not* the new shimv2 runtime instance (`containerd-shim-kata-v2` binary).
+
+The diagram below shows how the original architecture was simplified
+with the advent of shimv2.
+
+![Kubernetes integration with shimv2](../arch-images/shimv2.svg)

docs/design/architecture/kubernetes.md

@@ -0,0 +1,35 @@
+# Kubernetes support
+
+[Kubernetes](https://github.com/kubernetes/kubernetes/), or K8s, is a popular open source
+container orchestration engine. In Kubernetes, a set of containers sharing resources
+such as networking, storage, mount, PID, etc. is called a
+[pod](https://kubernetes.io/docs/user-guide/pods/).
+
+A node can have multiple pods, but at a minimum, a node within a Kubernetes cluster
+only needs to run a container runtime and a container agent (called a
+[Kubelet](https://kubernetes.io/docs/admin/kubelet/)).
+
+Kata Containers represents a Kubelet pod as a VM.
+
+A Kubernetes cluster runs a control plane where a scheduler (typically
+running on a dedicated master node) calls into a compute Kubelet. This
+Kubelet instance is responsible for managing the lifecycle of pods
+within the nodes and eventually relies on a container runtime to
+handle execution. The Kubelet architecture decouples lifecycle
+management from container execution through a dedicated gRPC based
+[Container Runtime Interface (CRI)](https://github.com/kubernetes/community/blob/master/contributors/design-proposals/node/container-runtime-interface-v1.md).
+
+In other words, a Kubelet is a CRI client and expects a CRI
+implementation to handle the server side of the interface.
+[CRI-O](https://github.com/kubernetes-incubator/cri-o) and
+[containerd](https://github.com/containerd/containerd/) are CRI
+implementations that rely on
+[OCI](https://github.com/opencontainers/runtime-spec) compatible
+runtimes for managing container instances.
+
+Kata Containers is an officially supported CRI-O and containerd
+runtime. Refer to the following guides on how to set up Kata
+Containers with Kubernetes:
+
+- [How to use Kata Containers and containerd](../../how-to/containerd-kata.md)
+- [Run Kata Containers with Kubernetes](../../how-to/run-kata-with-k8s.md)

docs/design/architecture/networking.md

@@ -0,0 +1,48 @@
+# Networking
+
+See the [networking document](networking.md).
+
+Containers will typically live in their own, possibly shared, networking namespace.
+At some point in a container lifecycle, container engines will set up that namespace
+to add the container to a network which is isolated from the host network, but
+which is shared between containers
+
+In order to do so, container engines will usually add one end of a virtual
+ethernet (`veth`) pair into the container networking namespace. The other end of
+the `veth` pair is added to the host networking namespace.
+
+This is a very namespace-centric approach as many hypervisors or VM
+Managers (VMMs) such as `virt-manager` cannot handle `veth`
+interfaces. Typically, `TAP` interfaces are created for VM
+connectivity.
+
+To overcome incompatibility between typical container engines expectations
+and virtual machines, Kata Containers networking transparently connects `veth`
+interfaces with `TAP` ones using Traffic Control:
+
+![Kata Containers networking](../arch-images/network.png)
+
+With a TC filter in place, a redirection is created between the container network and the
+virtual machine. As an example, the CNI may create a device, `eth0`, in the container's network
+namespace, which is a VETH device. Kata Containers will create a tap device for the VM, `tap0_kata`,
+and setup a TC redirection filter to mirror traffic from `eth0`'s ingress to `tap0_kata`'s egress,
+and a second to mirror traffic from `tap0_kata`'s ingress to `eth0`'s egress.
+
+Kata Containers maintains support for MACVTAP, which was an earlier implementation used in Kata. TC-filter
+is the default because it allows for simpler configuration, better CNI plugin compatibility, and performance
+on par with MACVTAP.
+
+Kata Containers has deprecated support for bridge due to lacking performance relative to TC-filter and MACVTAP.
+
+Kata Containers supports both
+[CNM](https://github.com/docker/libnetwork/blob/master/docs/design.md#the-container-network-model)
+and [CNI](https://github.com/containernetworking/cni) for networking management.
+
+## Network Hotplug
+
+Kata Containers has developed a set of network sub-commands and APIs to add, list and
+remove a guest network endpoint and to manipulate the guest route table.
+
+The following diagram illustrates the Kata Containers network hotplug workflow.
+
+![Network Hotplug](../arch-images/kata-containers-network-hotplug.png)

docs/design/architecture/storage.md

@@ -0,0 +1,44 @@
+# Storage
+
+## virtio SCSI
+
+If a block-based graph driver is [configured](README.md#configuration),
+`virtio-scsi` is used to _share_ the workload image (such as
+`busybox:latest`) into the container's environment inside the VM.
+
+## virtio FS
+
+If a block-based graph driver is _not_ [configured](README.md#configuration), a
+[`virtio-fs`](https://virtio-fs.gitlab.io) (`VIRTIO`) overlay
+filesystem mount point is used to _share_ the workload image instead. The
+[agent](README.md#agent) uses this mount point as the root filesystem for the
+container processes.
+
+For virtio-fs, the [runtime](README.md#runtime) starts one `virtiofsd` daemon
+(that runs in the host context) for each VM created.
+
+## Devicemapper
+
+The
+[devicemapper `snapshotter`](https://github.com/containerd/containerd/tree/master/snapshots/devmapper)
+is a special case. The `snapshotter` uses dedicated block devices
+rather than formatted filesystems, and operates at the block level
+rather than the file level. This knowledge is used to directly use the
+underlying block device instead of the overlay file system for the
+container root file system. The block device maps to the top
+read-write layer for the overlay. This approach gives much better I/O
+performance compared to using `virtio-fs` to share the container file
+system.
+
+#### Hot plug and unplug
+
+Kata Containers has the ability to hot plug add and hot plug remove
+block devices. This makes it possible to use block devices for
+containers started after the VM has been launched.
+
+Users can check to see if the container uses the `devicemapper` block
+device as its rootfs by calling `mount(8)` within the container. If
+the `devicemapper` block device is used, the root filesystem (`/`)
+will be mounted from `/dev/vda`. Users can disable direct mounting of
+the underlying block device through the runtime
+[configuration](README.md#configuration).

docs/design/data/metrics.yaml

@@ -1825,12 +1825,8 @@ components:
                   desc: ""
                 - value: grpc.StartContainerRequest
                   desc: ""
-                - value: grpc.StartTracingRequest
-                  desc: ""
                 - value: grpc.StatsContainerRequest
                   desc: ""
-                - value: grpc.StopTracingRequest
-                  desc: ""
                 - value: grpc.TtyWinResizeRequest
                   desc: ""
                 - value: grpc.UpdateContainerRequest

docs/design/host-cgroups.md

@@ -242,8 +242,8 @@ On the other hand, running all non vCPU threads under a dedicated overhead cgrou
 accurate metrics on the actual Kata Container pod overhead, allowing for tuning the overhead
 cgroup size and constraints accordingly.
 
-[linux-config]: https://github.com/opencontainers/runtime-spec/blob/master/config-linux.md
-[cgroupspath]: https://github.com/opencontainers/runtime-spec/blob/master/config-linux.md#cgroups-path
+[linux-config]: https://github.com/opencontainers/runtime-spec/blob/main/config-linux.md
+[cgroupspath]: https://github.com/opencontainers/runtime-spec/blob/main/config-linux.md#cgroups-path
 
 # Supported cgroups
 

docs/design/kata-2-0-metrics.md

@@ -1,21 +1,21 @@
 # Kata 2.0 Metrics Design
 
-Kata implement CRI's API and support [`ContainerStats`](https://github.com/kubernetes/kubernetes/blob/release-1.18/staging/src/k8s.io/cri-api/pkg/apis/runtime/v1alpha2/api.proto#L101) and [`ListContainerStats`](https://github.com/kubernetes/kubernetes/blob/release-1.18/staging/src/k8s.io/cri-api/pkg/apis/runtime/v1alpha2/api.proto#L103) interfaces to expose containers metrics. User can use these interface to get basic metrics about container.
+Kata implements CRI's API and supports [`ContainerStats`](https://github.com/kubernetes/kubernetes/blob/release-1.18/staging/src/k8s.io/cri-api/pkg/apis/runtime/v1alpha2/api.proto#L101) and [`ListContainerStats`](https://github.com/kubernetes/kubernetes/blob/release-1.18/staging/src/k8s.io/cri-api/pkg/apis/runtime/v1alpha2/api.proto#L103) interfaces to expose containers metrics. User can use these interfaces to get basic metrics about containers.
 
-But unlike `runc`, Kata is a VM-based runtime and has a different architecture.
+Unlike `runc`, Kata is a VM-based runtime and has a different architecture.
 
-## Limitations of Kata 1.x and the target of Kata 2.0
+## Limitations of Kata 1.x and target of Kata 2.0
 
 Kata 1.x has a number of limitations related to observability that may be obstacles to running Kata Containers at scale.
 
-In Kata 2.0, the following components will be able to provide more details about the system.
+In Kata 2.0, the following components will be able to provide more details about the system:
 
 - containerd shim v2 (effectively `kata-runtime`)
 - Hypervisor statistics
 - Agent process
 - Guest OS statistics
 
-> **Note**: In Kata 1.x, the main user-facing component was the runtime (`kata-runtime`). From 1.5, Kata then introduced the Kata containerd shim v2 (`containerd-shim-kata-v2`) which is essentially a modified runtime that is loaded by containerd to simplify and improve the way VM-based containers are created and managed.
+> **Note**: In Kata 1.x, the main user-facing component was the runtime (`kata-runtime`). From 1.5, Kata introduced the Kata containerd shim v2 (`containerd-shim-kata-v2`) which is essentially a modified runtime that is loaded by containerd to simplify and improve the way VM-based containers are created and managed.
 >
 > For Kata 2.0, the main component is the Kata containerd shim v2, although the deprecated `kata-runtime` binary will be maintained for a period of time.
 >
@@ -25,14 +25,15 @@ In Kata 2.0, the following components will be able to provide more details about
 
 Kata 2.0 metrics strongly depend on [Prometheus](https://prometheus.io/), a graduated project from CNCF.
 
-Kata Containers 2.0 introduces a new Kata component called `kata-monitor` which is used to monitor the other Kata components on the host. It's the monitor interface with Kata runtime, and we can do something like these:
+Kata Containers 2.0 introduces a new Kata component called `kata-monitor` which is used to monitor the Kata components on the host. It's shipped with the Kata runtime to provide an interface to:
 
 - Get metrics
 - Get events
 
-In this document we will cover metrics only. And until now it only supports metrics function.
+At present, `kata-monitor` supports retrieval of metrics only: this is what will be covered in this document.
 
-This is the architecture overview metrics in Kata Containers 2.0.
+
+This is the architecture overview of metrics in Kata Containers 2.0:
 
 ![Kata Containers 2.0 metrics](arch-images/kata-2-metrics.png)
 
@@ -45,38 +46,38 @@ For a quick evaluation, you can check out [this how to](../how-to/how-to-set-pro
 
 ### Kata monitor
 
-`kata-monitor` is a management agent on one node, where many Kata containers are running. `kata-monitor`'s work include:
+The `kata-monitor` management agent should be started on each node where the Kata containers runtime is installed. `kata-monitor` will:
 
-> **Note**: node is a single host system or a node in K8s clusters.
+> **Note**: a *node* running Kata containers will be either a single host system or a worker node belonging to a K8s cluster capable of running Kata pods.
 
-- Aggregate sandbox metrics running on this node, and add `sandbox_id` label
-- As a Prometheus target, all metrics from Kata shim on this node will be collected by Prometheus indirectly. This can easy the targets count in Prometheus, and also need not to expose shim's metrics by `ip:port`
+- Aggregate sandbox metrics running on the node, adding the `sandbox_id` label to them.
+- Expose a new Prometheus target, allowing all node metrics coming from the Kata shim to be collected by Prometheus indirectly. This simplifies the targets count in Prometheus and avoids exposing shim's metrics by `ip:port`.
 
-Only one `kata-monitor` process are running on one node.
+Only one `kata-monitor` process runs in each node.
 
-`kata-monitor` is using a different communication channel other than that `conatinerd` communicating with Kata shim, and Kata shim listen on a new socket address for communicating with `kata-monitor`.
+`kata-monitor` uses a different communication channel than the one used by the container engine (`containerd`/`CRI-O`) to communicate with the Kata shim. The Kata shim exposes a dedicated socket address reserved to `kata-monitor`.
 
-The way `kata-monitor` get shim's metrics socket file(`monitor_address`) like that `containerd` get shim address. The socket is an abstract socket and saved as file `abstract` with the same directory of `address` for `containerd`.
+The shim's metrics socket file is created under the virtcontainers sandboxes directory, i.e. `vc/sbs/${PODID}/shim-monitor.sock`.
 
-> **Note**: If there is no Prometheus server is configured, i.e., there is no scrape operations, `kata-monitor` will do nothing initiative.
+> **Note**: If there is no Prometheus server configured, i.e., there are no scrape operations, `kata-monitor` will not collect any metrics.
 
 ### Kata runtime
 
-Runtime is responsible for:
+Kata runtime is responsible for:
 
 - Gather metrics about shim process
 - Gather metrics about hypervisor process
 - Gather metrics about running sandbox
-- Get metrics from Kata agent(through `ttrpc`)
+- Get metrics from Kata agent (through `ttrpc`)
 
 ### Kata agent
 
-Agent is responsible for:
+Kata agent is responsible for:
 
 - Gather agent process metrics
 - Gather guest OS metrics
 
-And in Kata 2.0, agent will add a new interface:
+In Kata 2.0, the agent adds a new interface:
 
 ```protobuf
 rpc GetMetrics(GetMetricsRequest) returns (Metrics);
@@ -93,33 +94,49 @@ The `metrics` field is Prometheus encoded content. This can avoid defining a fix
 
 ### Performance and overhead
 
-Metrics should not become the bottleneck of system, downgrade the performance, and run with minimal overhead.
+Metrics should not become a bottleneck for the system or downgrade the performance: they should run with minimal overhead.
 
 Requirements:
 
 * Metrics **MUST** be quick to collect
-* Metrics **MUST** be small.
+* Metrics **MUST** be small
 * Metrics **MUST** be generated only if there are subscribers to the Kata metrics service
 * Metrics **MUST** be stateless
 
-In Kata 2.0, metrics are collected mainly from `/proc` filesystem, and consumed by Prometheus, based on a pull mode, that is mean if there is no Prometheus collector is running, so there will be zero overhead if nobody cares the metrics.
+In Kata 2.0, metrics are collected only when needed (pull mode), mainly from the `/proc` filesystem, and consumed by Prometheus. This means that if the Prometheus collector is not running (so no one cares about the metrics) the overhead will be zero.
 
-Metrics service also doesn't hold any metrics in memory.
+The metrics service also doesn't hold any metrics in memory.
+
+#### Metrics size ####
 
 |\*|No Sandbox | 1 Sandbox | 2 Sandboxes |
 |---|---|---|---|
 |Metrics count| 39 | 106 | 173 |
-|Metrics size(bytes)| 9K | 144K | 283K |
-|Metrics size(`gzipped`, bytes)| 2K | 10K | 17K |
+|Metrics size (bytes)| 9K | 144K | 283K |
+|Metrics size (`gzipped`, bytes)| 2K | 10K | 17K |
 
-*Metrics size*: Response size of one Prometheus scrape request.
+*Metrics size*: response size of one Prometheus scrape request.
 
-It's easy to estimated that if there are 10 sandboxes running in the host, the size of one metrics fetch request issued by Prometheus will be about to 9 + (144 - 9) * 10 = 1.35M (not `gzipped`) or 2 + (10 - 2) * 10 = 82K (`gzipped`). Of course Prometheus support `gzip` compression, that can reduce the response size of every request.
+It's easy to estimate the size of one metrics fetch request issued by Prometheus.
+The formula to calculate the expected size when no gzip compression is in place is:  
+9 + (144 - 9) * `number of kata sandboxes`
+
+Prometheus supports `gzip compression`. When enabled, the response size of each request will be smaller:  
+2 + (10 - 2) * `number of kata sandboxes`
+
+**Example**  
+We have 10 sandboxes running on a node. The expected size of one metrics fetch request issued by Prometheus against the kata-monitor agent running on that node will be:  
+9 + (144 - 9) * 10 = **1.35M**
+
+If `gzip compression` is enabled:  
+2 + (10 - 2) * 10 = **82K**
+
+#### Metrics delay ####
 
 And here is some test data:
 
-- End-to-end (from Prometheus server to `kata-monitor` and `kata-monitor` write response back): 20ms(avg)
-- Agent(RPC all from shim to agent): 3ms(avg)
+- End-to-end (from Prometheus server to `kata-monitor` and `kata-monitor` write response back): **20ms**(avg)
+- Agent (RPC all from shim to agent): **3ms**(avg)
 
 Test infrastructure:
 
@@ -128,13 +145,13 @@ Test infrastructure:
 
 **Scrape interval**
 
-Prometheus default `scrape_interval` is 1 minute, and usually it is set to 15s. Small `scrape_interval` will cause more overhead, so user should set it on monitor demand.
+Prometheus default `scrape_interval` is 1 minute, but it is usually set to 15 seconds. A smaller `scrape_interval` causes more overhead, so users should set it depending on their monitoring needs.
 
 ## Metrics list
 
-Here listed is all supported metrics by Kata 2.0. Some metrics is dependent on guest kernels in the VM, so there may be some different by your environment.
+Here are listed all the metrics supported by Kata 2.0. Some metrics are dependent on the VM guest kernel, so the available ones may differ based on the environment.
 
-Metrics is categorized by component where metrics are collected from and for.
+Metrics are categorized by the component from/for which the metrics are collected.
 
 * [Metric types](#metric-types)
 * [Kata agent metrics](#kata-agent-metrics)
@@ -145,15 +162,15 @@ Metrics is categorized by component where metrics are collected from and for.
 * [Kata containerd shim v2 metrics](#kata-containerd-shim-v2-metrics)
 
 > **Note**:
->  * Labels here are not include `instance` and `job` labels that added by Prometheus.
+>  * Labels here do not include the `instance` and `job` labels added by Prometheus.
 >  * Notes about metrics unit
 >    * `Kibibytes`, abbreviated `KiB`. 1 `KiB` equals 1024 B.
->    * For some metrics (like network devices statistics from file `/proc/net/dev`), unit is depend on label( for example `recv_bytes` and `recv_packets` are having different units).
->    * Most of these metrics is collected from `/proc` filesystem, so the unit of metrics are keeping the same unit as `/proc`. See the `proc(5)` manual page for further details.
+>    * For some metrics (like network devices statistics from file `/proc/net/dev`), unit depends on label( for example `recv_bytes` and `recv_packets` have different units).
+>    * Most of these metrics are collected from the `/proc` filesystem, so the unit of each metric matches the unit of the relevant `/proc` entry. See the `proc(5)` manual page for further details.
 
 ### Metric types
 
-Prometheus offer four core metric types.
+Prometheus offers four core metric types.
 
 - Counter: A counter is a cumulative metric that represents a single monotonically increasing counter whose value can only increase.
 
@@ -207,7 +224,7 @@ Metrics for Firecracker vmm.
 | `kata_firecracker_uart`: <br> Metrics specific to the UART device. | `GAUGE` |  | <ul><li>`item`<ul><li>`error_count`</li><li>`flush_count`</li><li>`missed_read_count`</li><li>`missed_write_count`</li><li>`read_count`</li><li>`write_count`</li></ul></li><li>`sandbox_id`</li></ul> | 2.0.0 |
 | `kata_firecracker_vcpu`: <br> Metrics specific to VCPUs' mode of functioning. | `GAUGE` |  | <ul><li>`item`<ul><li>`exit_io_in`</li><li>`exit_io_out`</li><li>`exit_mmio_read`</li><li>`exit_mmio_write`</li><li>`failures`</li><li>`filter_cpuid`</li></ul></li><li>`sandbox_id`</li></ul> | 2.0.0 |
 | `kata_firecracker_vmm`: <br> Metrics specific to the machine manager as a whole. | `GAUGE` |  | <ul><li>`item`<ul><li>`device_events`</li><li>`panic_count`</li></ul></li><li>`sandbox_id`</li></ul> | 2.0.0 |
-| `kata_firecracker_vsock`: <br> Vsock-related metrics. | `GAUGE` |  | <ul><li>`item`<ul><li>`activate_fails`</li><li>`cfg_fails`</li><li>`conn_event_fails`</li><li>`conns_added`</li><li>`conns_killed`</li><li>`conns_removed`</li><li>`ev_queue_event_fails`</li><li>`killq_resync`</li><li>`muxer_event_fails`</li><li>`rx_bytes_count`</li><li>`rx_packets_count`</li><li>`rx_queue_event_count`</li><li>`rx_queue_event_fails`</li><li>`rx_read_fails`</li><li>`tx_bytes_count`</li><li>`tx_flush_fails`</li><li>`tx_packets_count`</li><li>`tx_queue_event_count`</li><li>`tx_queue_event_fails`</li><li>`tx_write_fails`</li></ul></li><li>`sandbox_id`</li></ul> | 2.0.0 |
+| `kata_firecracker_vsock`: <br> VSOCK-related metrics. | `GAUGE` |  | <ul><li>`item`<ul><li>`activate_fails`</li><li>`cfg_fails`</li><li>`conn_event_fails`</li><li>`conns_added`</li><li>`conns_killed`</li><li>`conns_removed`</li><li>`ev_queue_event_fails`</li><li>`killq_resync`</li><li>`muxer_event_fails`</li><li>`rx_bytes_count`</li><li>`rx_packets_count`</li><li>`rx_queue_event_count`</li><li>`rx_queue_event_fails`</li><li>`rx_read_fails`</li><li>`tx_bytes_count`</li><li>`tx_flush_fails`</li><li>`tx_packets_count`</li><li>`tx_queue_event_count`</li><li>`tx_queue_event_fails`</li><li>`tx_write_fails`</li></ul></li><li>`sandbox_id`</li></ul> | 2.0.0 |
 
 ### Kata guest OS metrics
 
@@ -288,7 +305,7 @@ Metrics about Kata containerd shim v2 process.
 
 | Metric name | Type | Units | Labels | Introduced in Kata version |
 |---|---|---|---|---|
-| `kata_shim_agent_rpc_durations_histogram_milliseconds`: <br> RPC latency distributions. | `HISTOGRAM` | `milliseconds` | <ul><li>`action` (RPC actions of Kata agent)<ul><li>`grpc.CheckRequest`</li><li>`grpc.CloseStdinRequest`</li><li>`grpc.CopyFileRequest`</li><li>`grpc.CreateContainerRequest`</li><li>`grpc.CreateSandboxRequest`</li><li>`grpc.DestroySandboxRequest`</li><li>`grpc.ExecProcessRequest`</li><li>`grpc.GetMetricsRequest`</li><li>`grpc.GuestDetailsRequest`</li><li>`grpc.ListInterfacesRequest`</li><li>`grpc.ListProcessesRequest`</li><li>`grpc.ListRoutesRequest`</li><li>`grpc.MemHotplugByProbeRequest`</li><li>`grpc.OnlineCPUMemRequest`</li><li>`grpc.PauseContainerRequest`</li><li>`grpc.RemoveContainerRequest`</li><li>`grpc.ReseedRandomDevRequest`</li><li>`grpc.ResumeContainerRequest`</li><li>`grpc.SetGuestDateTimeRequest`</li><li>`grpc.SignalProcessRequest`</li><li>`grpc.StartContainerRequest`</li><li>`grpc.StartTracingRequest`</li><li>`grpc.StatsContainerRequest`</li><li>`grpc.StopTracingRequest`</li><li>`grpc.TtyWinResizeRequest`</li><li>`grpc.UpdateContainerRequest`</li><li>`grpc.UpdateInterfaceRequest`</li><li>`grpc.UpdateRoutesRequest`</li><li>`grpc.WaitProcessRequest`</li><li>`grpc.WriteStreamRequest`</li></ul></li><li>`sandbox_id`</li></ul> | 2.0.0 |
+| `kata_shim_agent_rpc_durations_histogram_milliseconds`: <br> RPC latency distributions. | `HISTOGRAM` | `milliseconds` | <ul><li>`action` (RPC actions of Kata agent)<ul><li>`grpc.CheckRequest`</li><li>`grpc.CloseStdinRequest`</li><li>`grpc.CopyFileRequest`</li><li>`grpc.CreateContainerRequest`</li><li>`grpc.CreateSandboxRequest`</li><li>`grpc.DestroySandboxRequest`</li><li>`grpc.ExecProcessRequest`</li><li>`grpc.GetMetricsRequest`</li><li>`grpc.GuestDetailsRequest`</li><li>`grpc.ListInterfacesRequest`</li><li>`grpc.ListProcessesRequest`</li><li>`grpc.ListRoutesRequest`</li><li>`grpc.MemHotplugByProbeRequest`</li><li>`grpc.OnlineCPUMemRequest`</li><li>`grpc.PauseContainerRequest`</li><li>`grpc.RemoveContainerRequest`</li><li>`grpc.ReseedRandomDevRequest`</li><li>`grpc.ResumeContainerRequest`</li><li>`grpc.SetGuestDateTimeRequest`</li><li>`grpc.SignalProcessRequest`</li><li>`grpc.StartContainerRequest`</li><li>`grpc.StatsContainerRequest`</li><li>`grpc.TtyWinResizeRequest`</li><li>`grpc.UpdateContainerRequest`</li><li>`grpc.UpdateInterfaceRequest`</li><li>`grpc.UpdateRoutesRequest`</li><li>`grpc.WaitProcessRequest`</li><li>`grpc.WriteStreamRequest`</li></ul></li><li>`sandbox_id`</li></ul> | 2.0.0 |
 | `kata_shim_fds`: <br> Kata containerd shim v2 open FDs. | `GAUGE` |  | <ul><li>`sandbox_id`</li></ul> | 2.0.0 |
 | `kata_shim_go_gc_duration_seconds`: <br> A summary of the pause duration of garbage collection cycles. | `SUMMARY` | `seconds` | <ul><li>`sandbox_id`</li></ul> | 2.0.0 |
 | `kata_shim_go_goroutines`: <br> Number of goroutines that currently exist. | `GAUGE` |  | <ul><li>`sandbox_id`</li></ul> | 2.0.0 |

docs/design/kata-design-requirements.md

@@ -30,7 +30,7 @@ The Kata Containers runtime **MUST** implement the following command line option
 The Kata Containers project **MUST** provide two interfaces for CRI shims to manage hardware
 virtualization based Kubernetes pods and containers:
 -  An OCI and `runc` compatible command line interface, as described in the previous section.
-This interface is used by implementations such as [`CRI-O`](http://cri-o.io) and [`cri-containerd`](https://github.com/containerd/cri-containerd), for example.
+This interface is used by implementations such as [`CRI-O`](http://cri-o.io) and [`containerd`](https://github.com/containerd/containerd), for example.
 - A hardware virtualization runtime library API for CRI shims to consume and provide a more
 CRI native implementation. The [`frakti`](https://github.com/kubernetes/frakti) CRI shim is an example of such a consumer.
 

docs/design/proposals/tracing-proposals.md

@@ -209,5 +209,5 @@ network accessible to the collector.
 - The trace collection proposals are still being considered.
 
 [kata-1x-tracing]: https://github.com/kata-containers/agent/blob/master/TRACING.md
-[trace-forwarder]: /src/trace-forwarder
+[trace-forwarder]: /src/tools/trace-forwarder
 [tracing-doc-pr]: https://github.com/kata-containers/kata-containers/pull/1937

docs/design/virtualization.md

@@ -41,7 +41,7 @@ Kata Containers with QEMU has complete compatibility with Kubernetes.
 Depending on the host architecture, Kata Containers supports various machine types,
 for example `pc` and `q35` on x86 systems, `virt` on ARM systems and `pseries` on IBM Power systems. The default Kata Containers
 machine type is `pc`. The machine type and its [`Machine accelerators`](#machine-accelerators) can
-be changed by editing the runtime [`configuration`](./architecture.md/#configuration) file.
+be changed by editing the runtime [`configuration`](architecture/README.md#configuration) file.
 
 Devices and features used:
 - virtio VSOCK or virtio serial

docs/how-to/README.md

@@ -5,7 +5,7 @@
 - [Run Kata containers with `crictl`](run-kata-with-crictl.md)
 - [Run Kata Containers with Kubernetes](run-kata-with-k8s.md)
 - [How to use Kata Containers and Containerd](containerd-kata.md)
-- [How to use Kata Containers and CRI (containerd plugin) with Kubernetes](how-to-use-k8s-with-cri-containerd-and-kata.md)
+- [How to use Kata Containers and CRI (containerd) with Kubernetes](how-to-use-k8s-with-cri-containerd-and-kata.md)
 - [Kata Containers and service mesh for Kubernetes](service-mesh.md)
 - [How to import Kata Containers logs into Fluentd](how-to-import-kata-logs-with-fluentd.md)
 
@@ -36,3 +36,4 @@
 - [How to use hotplug memory on arm64 in Kata Containers](how-to-hotplug-memory-arm64.md)
 - [How to setup swap devices in guest kernel](how-to-setup-swap-devices-in-guest-kernel.md)
 - [How to run rootless vmm](how-to-run-rootless-vmm.md)
+- [How to run Docker with Kata Containers](how-to-run-docker-with-kata.md)

docs/how-to/how-to-run-docker-with-kata.md

@@ -0,0 +1,141 @@
+# How to run Docker in Docker with Kata Containers
+
+This document describes the why and how behind running Docker in a Kata Container.
+
+> **Note:** While in other environments this might be described as "Docker in Docker", the new architecture of Kata 2.x means [Docker can no longer be used to create containers using a Kata Containers runtime](https://github.com/kata-containers/kata-containers/issues/722).
+
+## Requirements
+
+- A working Kata Containers installation
+
+## Install and configure Kata Containers
+
+Follow the [Kata Containers installation guide](../install/README.md) to Install Kata Containers on your Kubernetes cluster.
+
+## Background
+
+Docker in Docker ("DinD") is the colloquial name for the ability to run `docker` from inside a container.
+
+You can learn more about about Docker-in-Docker at the following links:
+
+- [The original announcement of DinD](https://www.docker.com/blog/docker-can-now-run-within-docker/)
+- [`docker` image Docker Hub page](https://hub.docker.com/_/docker/) (this page lists the `-dind` releases)
+
+While normally DinD refers to running `docker` from inside a Docker container,
+Kata Containers 2.x allows only supported runtimes (such as [`containerd`](../install/container-manager/containerd/containerd-install.md)).
+
+Running `docker` in a Kata Container implies creating Docker containers from inside a container managed by `containerd` (or another supported container manager), as illustrated below:
+
+```
+container manager -> Kata Containers shim     -> Docker Daemon -> Docker container
+(containerd)        (containerd-shim-kata-v2)    (dockerd)        (busybox sh)
+```
+
+[OverlayFS][OverlayFS] is the preferred storage driver for most container runtimes on Linux ([including Docker](https://docs.docker.com/storage/storagedriver/select-storage-driver)).
+
+> **Note:** While in the past Kata Containers did not contain the [`overlay` kernel module (aka OverlayFS)][OverlayFS], the kernel modules have been included since the [Kata Containers v2.0.0 release][v2.0.0].
+
+[OverlayFS]: https://www.kernel.org/doc/html/latest/filesystems/overlayfs.html
+[v2.0.0]: https://github.com/kata-containers/kata-containers/releases/tag/2.0.0
+[kata-2.x-supported-runtimes]: https://github.com/kata-containers/kata-containers/blob/5737b36a3513f4da11a9dc7301b0c97ea22a51cf/docs/install/container-manager/containerd/containerd-install.md
+
+## Why Docker in Kata Containers 2.x requires special measures
+
+Running Docker containers Kata Containers requires care because `VOLUME`s specified in `Dockerfile`s run by Kata Containers are given the `kataShared` mount type by default, which applies to the root directory `/`:
+
+```console
+/ # mount
+kataShared on / type virtiofs (rw,relatime,dax)
+```
+
+`kataShared` mount types are powered by [`virtio-fs`][virtio-fs], a marked improvement over `virtio-9p`, thanks to [PR #1016](https://github.com/kata-containers/runtime/pull/1016). While `virtio-fs` is normally an excellent choice, in the case of DinD workloads `virtio-fs` causes an issue -- [it *cannot* be used as a "upper layer" of `overlayfs` without a custom patch](http://lists.katacontainers.io/pipermail/kata-dev/2020-January/001216.html).
+
+As `/var/lib/docker` is a `VOLUME` specified by DinD (i.e. the `docker` images tagged `*-dind`/`*-dind-rootless`), `docker` fill fail to start (or even worse, silently pick a worse storage driver like `vfs`) when started in a Kata Container. Special measures must be taken when running DinD-powered workloads in Kata Containers.
+
+## Workarounds/Solutions
+
+Thanks to various community contributions (see [issue references below](#references)) the following options, with various trade-offs have been uncovered:
+
+### Use a memory backed volume
+
+For small workloads (small container images, without much generated filesystem load), a memory-backed volume is sufficient. Kubernetes supports a variant of  [the `EmptyDir` volume][k8s-emptydir], which allows for memdisk-backed storage -- the [the `medium: Memory` ][k8s-memory-volume-type]. An example of a `Pod` using such a setup [was contributed](https://github.com/kata-containers/runtime/issues/1429#issuecomment-477385283), and is reproduced below:
+
+```yaml
+apiVersion: v1
+kind: Pod
+metadata:
+  name: dind
+spec:
+  runtimeClassName: kata
+  containers:
+  - name: dind
+    securityContext:
+      privileged: true
+    image: docker:20.10-dind
+    args: ["--storage-driver=overlay2"]
+    resources:
+      limits:
+        memory: "3G"
+    volumeMounts:
+      - mountPath: /var/run/
+        name: dockersock
+      - mountPath: /var/lib/docker
+        name: docker
+  volumes:
+    - name: dockersock
+      emptyDir: {}
+    - name: docker
+      emptyDir:
+        medium: Memory
+```
+
+Inside the container you can view the mount:
+
+```console
+/ # mount | grep lib\/docker
+tmpfs on /var/lib/docker type tmpfs (rw,relatime)
+```
+
+As is mentioned in the comment encapsulating this code, using volatile memory for container storage backing is a risky and could be possibly wasteful on machines that do not have a lot of RAM.
+
+### Use a loop mounted disk
+
+Using a loop mounted disk that is provisioned shortly before starting of the container workload is another approach that yields good performance.
+
+Contributors provided [an example in issue #1888](https://github.com/kata-containers/runtime/issues/1888#issuecomment-739057384), which is reproduced in part below:
+
+```yaml
+spec:
+  containers:
+    - name: docker
+      image: docker:20.10-dind
+      command: ["sh", "-c"]
+      args:
+      - if [[ $(df -PT /var/lib/docker | awk 'NR==2 {print $2}') == virtiofs ]]; then
+          apk add e2fsprogs &&
+          truncate -s 20G /tmp/disk.img &&
+          mkfs.ext4 /tmp/disk.img &&
+          mount /tmp/disk.img /var/lib/docker; fi &&
+        dockerd-entrypoint.sh;
+      securityContext:
+        privileged: true
+```
+
+Note that loop mounted disks are often sparse, which means they *do not* take up the full amount of space that has been provisioned. This solution seems to produce the best performance and flexibility, at the expense of increased complexity and additional required setup.
+
+### Build a custom kernel
+
+It's possible to [modify the kernel](https://github.com/kata-containers/runtime/issues/1888#issuecomment-616872558) (in addition to applying the earlier mentioned mailing list patch) to support using `virtio-fs` as an upper. Note that if you modify your kernel and use `virtio-fs` you may require [additional changes](https://github.com/kata-containers/runtime/issues/1888#issuecomment-739057384) for decent performance and to address other issues.
+
+> **NOTE:** A future kernel release may rectify the usability and performance issues of using `virtio-fs` as an OverlayFS upper layer.
+
+## References
+
+The solutions proposed in this document are an amalgamation of thoughtful contributions from the Kata Containers community.
+
+Find links to issues & related discussion and the fruits therein below:
+
+- [How to run Docker in Docker with Kata Containers (#2474)](https://github.com/kata-containers/kata-containers/issues/2474)
+- [Does Kata-container support AUFS/OverlayFS? (#2493)](https://github.com/kata-containers/runtime/issues/2493)
+- [Unable to start docker in docker with virtio-fs (#1888)](https://github.com/kata-containers/runtime/issues/1888)
+- [Not using native diff for overlay2 (#1429)](https://github.com/kata-containers/runtime/issues/1429)

docs/how-to/how-to-set-sandbox-config-kata.md

@@ -34,8 +34,6 @@ There are several kinds of Kata configurations and they are listed below.
 | `io.katacontainers.config.agent.enable_tracing` | `boolean` | enable tracing for the agent |
 | `io.katacontainers.config.agent.container_pipe_size` | uint32 | specify the size of the std(in/out) pipes created for containers |
 | `io.katacontainers.config.agent.kernel_modules` | string | the list of kernel modules and their parameters that will be loaded in the guest kernel. Semicolon separated list of kernel modules and their parameters. These modules will be loaded in the guest kernel using `modprobe`(8). E.g., `e1000e InterruptThrottleRate=3000,3000,3000 EEE=1; i915 enable_ppgtt=0` |
-| `io.katacontainers.config.agent.trace_mode` | string | the trace mode for the agent |
-| `io.katacontainers.config.agent.trace_type` | string | the trace type for the agent |
 
 ## Hypervisor Options
 | Key | Value Type | Comments |

docs/how-to/how-to-use-k8s-with-cri-containerd-and-kata.md

@@ -3,7 +3,7 @@
 This document describes how to set up a single-machine Kubernetes (k8s) cluster.
 
 The Kubernetes cluster will use the
-[CRI containerd plugin](https://github.com/containerd/containerd/tree/main/pkg/cri) and
+[CRI containerd](https://github.com/containerd/containerd/) and
 [Kata Containers](https://katacontainers.io) to launch untrusted workloads.
 
 ## Requirements
@@ -71,12 +71,12 @@ $ for service in ${services}; do
     service_dir="/etc/systemd/system/${service}.service.d/"
     sudo mkdir -p ${service_dir}
 
-    cat << EOT | sudo tee "${service_dir}/proxy.conf"
+    cat << EOF | sudo tee "${service_dir}/proxy.conf"
 [Service]
 Environment="HTTP_PROXY=${http_proxy}"
 Environment="HTTPS_PROXY=${https_proxy}"
 Environment="NO_PROXY=${no_proxy}"
-EOT
+EOF
 done
 
 $ sudo systemctl daemon-reload
@@ -172,7 +172,7 @@ If a pod has the `runtimeClassName` set to `kata`, the CRI plugin runs the pod w
 - Create an pod configuration that using Kata Containers runtime
 
   ```bash
-  $ cat << EOT | tee nginx-kata.yaml
+  $ cat << EOF | tee nginx-kata.yaml
   apiVersion: v1
   kind: Pod
   metadata:
@@ -183,7 +183,7 @@ If a pod has the `runtimeClassName` set to `kata`, the CRI plugin runs the pod w
     - name: nginx
       image: nginx
       
-  EOT
+  EOF
   ```
 
 - Create the pod

docs/how-to/how-to-use-kata-containers-with-acrn.md

@@ -22,7 +22,7 @@ This document requires the presence of the ACRN hypervisor and Kata Containers o
 
 - ACRN supported [Hardware](https://projectacrn.github.io/latest/hardware.html#supported-hardware).
   > **Note:** Please make sure to have a minimum of 4 logical processors (HT) or cores.
-- ACRN [software](https://projectacrn.github.io/latest/tutorials/kbl-nuc-sdc.html#use-the-script-to-set-up-acrn-automatically) setup.
+- ACRN [software](https://projectacrn.github.io/latest/tutorials/run_kata_containers.html) setup.
 - For networking, ACRN supports either MACVTAP or TAP. If MACVTAP is not enabled in the Service OS, please follow the below steps to update the kernel:
 
   ```sh

docs/how-to/privileged.md

@@ -16,9 +16,9 @@ from the host, a potentially undesirable side-effect that decreases the security
 
 The following sections document how to configure this behavior in different container runtimes.
 
-#### Containerd and CRI
+#### Containerd
 
-The Containerd CRI allows configuring the privileged host devices behavior for each runtime in the CRI config. This is
+The Containerd allows configuring the privileged host devices behavior for each runtime in the containerd config. This is
 done with the `privileged_without_host_devices` option. Setting this to `true` will disable hot plugging of the host 
 devices into the guest, even when privileged is enabled.
 
@@ -41,7 +41,7 @@ See below example config:
 ```
 
  - [Kata Containers with Containerd and CRI documentation](how-to-use-k8s-with-cri-containerd-and-kata.md)
- - [Containerd CRI config documentation](https://github.com/containerd/cri/blob/master/docs/config.md)
+ - [Containerd CRI config documentation](https://github.com/containerd/containerd/blob/main/docs/cri/config.md)
 
 #### CRI-O
 

docs/how-to/run-kata-with-k8s.md

@@ -9,7 +9,7 @@ Kubernetes CRI (Container Runtime Interface) implementations allow using any
 OCI-compatible runtime with Kubernetes, such as the Kata Containers runtime.
 
 Kata Containers support both the [CRI-O](https://github.com/kubernetes-incubator/cri-o) and
-[CRI-containerd](https://github.com/containerd/cri) CRI implementations.
+[containerd](https://github.com/containerd/containerd) CRI implementations.
 
 After choosing one CRI implementation, you must make the appropriate configuration
 to ensure it integrates with Kata Containers.
@@ -20,9 +20,9 @@ required to spawn pods and containers, and this is the preferred way to run Kata
 An equivalent shim implementation for CRI-O is planned.
 
 ### CRI-O
-For CRI-O installation instructions, refer to the [CRI-O Tutorial](https://github.com/kubernetes-incubator/cri-o/blob/master/tutorial.md) page.
+For CRI-O installation instructions, refer to the [CRI-O Tutorial](https://github.com/cri-o/cri-o/blob/main/tutorial.md) page.
 
-The following sections show how to set up the CRI-O configuration file (default path: `/etc/crio/crio.conf`) for Kata.
+The following sections show how to set up the CRI-O snippet configuration file (default path: `/etc/crio/crio.conf`) for Kata.
 
 Unless otherwise stated, all the following settings are specific to the `crio.runtime` table:
 ```toml
@@ -30,7 +30,7 @@ Unless otherwise stated, all the following settings are specific to the `crio.ru
 # runtime used and options for how to set up and manage the OCI runtime.
 [crio.runtime]
 ```
-A comprehensive documentation of the configuration file can be found [here](https://github.com/cri-o/cri-o/blob/master/docs/crio.conf.5.md).
+A comprehensive documentation of the configuration file can be found [here](https://github.com/cri-o/cri-o/blob/main/docs/crio.conf.5.md).
 
 > **Note**: After any change to this file, the CRI-O daemon have to be restarted with:
 >````
@@ -40,82 +40,20 @@ A comprehensive documentation of the configuration file can be found [here](http
 #### Kubernetes Runtime Class (CRI-O v1.12+)
 The [Kubernetes Runtime Class](https://kubernetes.io/docs/concepts/containers/runtime-class/)
 is the preferred way of specifying the container runtime configuration to run a Pod's containers.
-To use this feature, Kata must added as a runtime handler with:
+To use this feature, Kata must added as a runtime handler. This can be done by
+dropping a `50-kata` snippet file into `/etc/crio/crio.conf.d`, with the
+content shown below:
 
 ```toml
-[crio.runtime.runtimes.kata-runtime]
-  runtime_path = "/usr/bin/kata-runtime"
-  runtime_type = "oci"
-```
-
-You can also add multiple entries to specify alternatives hypervisors, e.g.:
-```toml
-[crio.runtime.runtimes.kata-qemu]
-  runtime_path = "/usr/bin/kata-runtime"
-  runtime_type = "oci"
-
-[crio.runtime.runtimes.kata-fc]
-  runtime_path = "/usr/bin/kata-runtime"
-  runtime_type = "oci"
-```
-
-#### Untrusted annotation (until CRI-O v1.12)
-The untrusted annotation is used to specify a runtime for __untrusted__ workloads, i.e.
-a runtime to be used when the workload cannot be trusted and a higher level of security
-is required. An additional flag can be used to let CRI-O know if a workload
-should be considered _trusted_ or _untrusted_ by default.
-For further details, see the documentation
-[here](../design/architecture.md#mixing-vm-based-and-namespace-based-runtimes).
-
-```toml
-# runtime is the OCI compatible runtime used for trusted container workloads.
-# This is a mandatory setting as this runtime will be the default one
-# and will also be used for untrusted container workloads if
-# runtime_untrusted_workload is not set.
-runtime = "/usr/bin/runc"
-
-# runtime_untrusted_workload is the OCI compatible runtime used for untrusted
-# container workloads. This is an optional setting, except if
-# default_container_trust is set to "untrusted".
-runtime_untrusted_workload = "/usr/bin/kata-runtime"
-
-# default_workload_trust is the default level of trust crio puts in container
-# workloads. It can either be "trusted" or "untrusted", and the default
-# is "trusted".
-# Containers can be run through different container runtimes, depending on
-# the trust hints we receive from kubelet:
-# - If kubelet tags a container workload as untrusted, crio will try first to
-# run it through the untrusted container workload runtime. If it is not set,
-# crio will use the trusted runtime.
-# - If kubelet does not provide any information about the container workload trust
-# level, the selected runtime will depend on the default_container_trust setting.
-# If it is set to "untrusted", then all containers except for the host privileged
-# ones, will be run by the runtime_untrusted_workload runtime. Host privileged
-# containers are by definition trusted and will always use the trusted container
-# runtime. If default_container_trust is set to "trusted", crio will use the trusted
-# container runtime for all containers.
-default_workload_trust = "untrusted"
-```
-
-#### Network namespace management
-To enable networking for the workloads run by Kata, CRI-O needs to be configured to
-manage network namespaces, by setting the following key to `true`.
-
-In CRI-O v1.16:
-```toml
-manage_network_ns_lifecycle = true
-```
-In CRI-O v1.17+:
-```toml
-manage_ns_lifecycle = true
+[crio.runtime.runtimes.kata]
+	runtime_path = "/usr/bin/containerd-shim-kata-v2"
+	runtime_type = "vm"
+	runtime_root = "/run/vc"
+	privileged_without_host_devices = true
 ```
 
 
-### containerd with CRI plugin
-
-If you select containerd with `cri` plugin, follow the "Getting Started for Developers"
-instructions [here](https://github.com/containerd/cri#getting-started-for-developers)
-to properly install it.
+### containerd
 
 To customize containerd to select Kata Containers runtime, follow our
 "Configure containerd to use Kata Containers" internal documentation
@@ -160,7 +98,7 @@ $ sudo systemctl restart kubelet
 # If using CRI-O
 $ sudo kubeadm init --ignore-preflight-errors=all --cri-socket /var/run/crio/crio.sock --pod-network-cidr=10.244.0.0/16
 
-# If using CRI-containerd
+# If using containerd
 $ sudo kubeadm init --ignore-preflight-errors=all --cri-socket /run/containerd/containerd.sock --pod-network-cidr=10.244.0.0/16
 
 $ export KUBECONFIG=/etc/kubernetes/admin.conf

docs/how-to/service-mesh.md

@@ -34,7 +34,7 @@ as the proxy starts.
 
 Follow the [instructions](../install/README.md)
 to get Kata Containers properly installed and configured with Kubernetes.
-You can choose between CRI-O and CRI-containerd, both are supported
+You can choose between CRI-O and containerd, both are supported
 through this document.
 
 For both cases, select the workloads as _trusted_ by default. This way,
@@ -159,7 +159,7 @@ containers with `privileged: true` to `privileged: false`.
 There is no difference between Istio and Linkerd in this section. It is
 about which CRI implementation you use.
 
-For both CRI-O and CRI-containerd, you have to add an annotation indicating
+For both CRI-O and containerd, you have to add an annotation indicating
 the workload for this deployment is not _trusted_, which will trigger
 `kata-runtime` to be called instead of `runc`.
 
@@ -193,9 +193,9 @@ spec:
 ...
 ```
 
-__CRI-containerd:__
+__containerd:__
 
-Add the following annotation for CRI-containerd
+Add the following annotation for containerd
 ```yaml
 io.kubernetes.cri.untrusted-workload: "true"
 ```

docs/install/README.md

@@ -12,16 +12,26 @@ Containers.
 
 Packaged installation methods uses your distribution's native package format (such as RPM or DEB).
 
-*Note:* We encourage installation methods that provides automatic updates, it ensures security updates and bug fixes are
-easily applied.
+> **Note:** We encourage installation methods that provides automatic updates, it ensures security updates and bug fixes are
+> easily applied.
 
-| Installation method                                  | Description                                                         | Automatic updates | Use case                                                 |
-|------------------------------------------------------|---------------------------------------------------------------------|-------------------|----------------------------------------------------------|
-| [Using official distro packages](#official-packages) | Kata packages provided by Linux distributions official repositories | yes               | Recommended for most users.                              |
-| [Using snap](#snap-installation)                     | Easy to install                                                     | yes               | Good alternative to official distro packages.            |
-| [Automatic](#automatic-installation)                 | Run a single command to install a full system                       | **No!**           | For those wanting the latest release quickly.            |
-| [Manual](#manual-installation)                       | Follow a guide step-by-step to install a working system             | **No!**           | For those who want the latest release with more control. |
-| [Build from source](#build-from-source-installation) | Build the software components manually                              | **No!**           | Power users and developers only.                         |
+| Installation method                                  | Description                                                                                  | Automatic updates | Use case                                                                                      |
+|------------------------------------------------------|----------------------------------------------------------------------------------------------|-------------------|-----------------------------------------------------------------------------------------------|
+| [Using kata-deploy](#kata-deploy-installation)       | The preferred way to deploy the Kata Containers distributed binaries on a Kubernetes cluster | **No!**           | Best way to give it a try on kata-containers on an already up and running Kubernetes cluster. | 
+| [Using official distro packages](#official-packages) | Kata packages provided by Linux distributions official repositories                          | yes               | Recommended for most users.                                                                   |
+| [Using snap](#snap-installation)                     | Easy to install                                                                              | yes               | Good alternative to official distro packages.                                                 |
+| [Automatic](#automatic-installation)                 | Run a single command to install a full system                                                | **No!**           | For those wanting the latest release quickly.                                                 |
+| [Manual](#manual-installation)                       | Follow a guide step-by-step to install a working system                                      | **No!**           | For those who want the latest release with more control.                                      |
+| [Build from source](#build-from-source-installation) | Build the software components manually                                                       | **No!**           | Power users and developers only.                                                              |
+
+### Kata Deploy Installation
+
+Kata Deploy provides a Dockerfile, which contains all of the binaries and
+artifacts required to run Kata Containers, as well as reference DaemonSets,
+which can be utilized to install Kata Containers on a running Kubernetes
+cluster.
+
+[Use Kata Deploy](/tools/packaging/kata-deploy/README.md) to install Kata Containers on a Kubernetes Cluster.
 
 ### Official packages
 
@@ -48,9 +58,9 @@ Follow the [containerd installation guide](container-manager/containerd/containe
 
 ## Build from source installation
 
-*Note:* Power users who decide to build from sources should be aware of the
-implications of using an unpackaged system which will not be automatically
-updated as new [releases](../Stable-Branch-Strategy.md) are made available.
+> **Note:** Power users who decide to build from sources should be aware of the
+> implications of using an unpackaged system which will not be automatically
+> updated as new [releases](../Stable-Branch-Strategy.md) are made available.
 
 [Building from sources](../Developer-Guide.md#initial-setup)  allows power users
 who are comfortable building software from source to use the latest component

docs/tracing.md

@@ -0,0 +1,213 @@
+# Overview
+
+This document explains how to trace Kata Containers components.
+
+# Introduction
+
+The Kata Containers runtime and agent are able to generate
+[OpenTelemetry][opentelemetry] trace spans, which allow the administrator to
+observe what those components are doing and how much time they are spending on
+each operation.
+
+# OpenTelemetry summary
+
+An OpenTelemetry-enabled application creates a number of trace "spans". A span
+contains the following attributes:
+
+- A name
+- A pair of timestamps (recording the start time and end time of some operation)
+- A reference to the span's parent span
+
+All spans need to be *finished*, or *completed*, to allow the OpenTelemetry
+framework to generate the final trace information (by effectively closing the
+transaction encompassing the initial (root) span and all its children).
+
+For Kata, the root span represents the total amount of time taken to run a
+particular component from startup to its shutdown (the "run time").
+
+# Architecture
+
+## Runtime tracing architecture
+
+The runtime, which runs in the host environment, has been modified to
+optionally generate trace spans which are sent to a trace collector on the
+host.
+
+## Agent tracing architecture
+
+An OpenTelemetry system (such as [Jaeger][jaeger-tracing]) uses a collector to
+gather up trace spans from the application for viewing and processing. For an
+application to use the collector, it must run in the same context as
+the collector.
+
+This poses a problem for tracing the Kata Containers agent since it does not
+run in the same context as the collector: it runs inside a virtual machine (VM).
+
+To allow spans from the agent to be sent to the trace collector, Kata provides
+a [trace forwarder][trace-forwarder] component. This runs in the same context
+as the collector (generally on the host system) and listens on a
+[`VSOCK`][vsock] channel for traces generated by the agent, forwarding them on
+to the trace collector.
+
+> **Note:**
+>
+> This design supports agent tracing without having to make changes to the
+> image, but also means that [custom images][osbuilder] can also benefit from
+> agent tracing.
+
+The following diagram summarises the architecture used to trace the Kata
+Containers agent:
+
+```
++--------------------------------------------+
+| Host                                       |
+|                                            |
+| +---------------+                          |
+| | OpenTelemetry |                          |
+| | Trace         |                          |
+| | Collector     |                          |
+| +---------------+                          |
+|       ^                  +---------------+ |
+|       | spans            | Kata VM       | |
+| +-----+-----+            |               | |
+| | Kata      |    spans   o     +-------+ | |
+| | Trace     |<-----------------| Kata  | | |
+| | Forwarder |    VSOCK   o     | Agent | | |
+| +-----------+    Channel |     +-------+ | |
+|                          +---------------+ |
++--------------------------------------------+
+```
+
+# Agent tracing prerequisites
+
+- You must have a trace collector running.
+
+  Although the collector normally runs on the host, it can also be run from
+  inside a Docker image configured to expose the appropriate host ports to the
+  collector.
+
+  The [Jaeger "all-in-one" Docker image][jaeger-all-in-one] method
+  is the quickest and simplest way to run the collector for testing.
+
+- If you wish to trace the agent, you must start the
+  [trace forwarder][trace-forwarder].
+
+> **Notes:**
+>
+> - If agent tracing is enabled but the forwarder is not running,
+>   the agent will log an error (signalling that it cannot generate trace
+>   spans), but continue to work as normal.
+>
+> - The trace forwarder requires a trace collector (such as Jaeger) to be
+>   running before it is started. If a collector is not running, the trace
+>   forwarder will exit with an error.
+
+# Enable tracing
+
+By default, tracing is disabled for all components. To enable _any_ form of
+tracing an `enable_tracing` option must be enabled for at least one component.
+
+> **Note:** 
+>
+> Enabling this option will only allow tracing for subsequently
+> started containers.
+
+## Enable runtime tracing
+
+To enable runtime tracing, set the tracing option as shown:
+
+```toml
+[runtime]
+enable_tracing = true
+```
+
+## Enable agent tracing
+
+To enable agent tracing, set the tracing option as shown:
+
+```toml
+[agent.kata]
+enable_tracing = true
+```
+
+> **Note:**
+>
+> If both agent tracing and runtime tracing are enabled, the resulting trace
+> spans will be "collated": expanding individual runtime spans in the Jaeger
+> web UI will show the agent trace spans resulting from the runtime
+> operation.
+
+# Appendices
+
+## Agent tracing requirements
+
+### Host environment
+
+- The host kernel must support the VSOCK socket type.
+
+  This will be available if the kernel is built with the
+  `CONFIG_VHOST_VSOCK` configuration option.
+
+- The VSOCK kernel module must be loaded:
+
+   ```
+   $ sudo modprobe vhost_vsock
+   ```
+
+### Guest environment
+
+- The guest kernel must support the VSOCK socket type:
+
+  This will be available if the kernel is built with the
+  `CONFIG_VIRTIO_VSOCKETS` configuration option.
+
+  > **Note:** The default Kata Containers guest kernel provides this feature.
+
+## Agent tracing limitations
+
+- Agent tracing is only "completed" when the workload and the Kata agent
+  process have exited.
+
+  Although trace information *can* be inspected before the workload and agent
+  have exited, it is incomplete. This is shown as `<trace-without-root-span>`
+  in the Jaeger web UI.
+
+  If the workload is still running, the trace transaction -- which spans the entire
+  runtime of the Kata agent -- will not have been completed. To view the complete
+  trace details, wait for the workload to end, or stop the container.
+
+## Performance impact
+
+[OpenTelemetry][opentelemetry] is designed for high performance. It combines
+the best of two previous generation projects (OpenTracing and OpenCensus) and
+uses a very efficient mechanism to capture trace spans. Further, the trace
+points inserted into the agent are generated dynamically at compile time. This
+is advantageous since new versions of the agent will automatically benefit
+from improvements in the tracing infrastructure. Overall, the impact of
+enabling runtime and agent tracing should be extremely low.
+
+## Agent shutdown behaviour
+ 
+In normal operation, the Kata runtime manages the VM shutdown and performs
+certain optimisations to speed up this process. However, if agent tracing is
+enabled, the agent itself is responsible for shutting down the VM. This it to
+ensure all agent trace transactions are completed. This means there will be a
+small performance impact for container shutdown when agent tracing is enabled
+as the runtime must wait for the VM to shutdown fully.
+
+## Set up a tracing development environment
+
+If you want to debug, further develop, or test tracing,
+[enabling full debug][enable-full-debug]
+is highly recommended. For working with the agent, you may also wish to
+[enable a debug console][setup-debug-console]
+to allow you to access the VM environment.
+
+[enable-full-debug]: https://github.com/kata-containers/kata-containers/blob/main/docs/Developer-Guide.md#enable-full-debug
+[jaeger-all-in-one]: https://www.jaegertracing.io/docs/getting-started/
+[jaeger-tracing]: https://www.jaegertracing.io
+[opentelemetry]: https://opentelemetry.io
+[osbuilder]: https://github.com/kata-containers/kata-containers/blob/main/tools/osbuilder
+[setup-debug-console]: https://github.com/kata-containers/kata-containers/blob/main/docs/Developer-Guide.md#set-up-a-debug-console
+[trace-forwarder]: /src/tools/trace-forwarder
+[vsock]: https://wiki.qemu.org/Features/VirtioVsock

docs/use-cases/using-Intel-QAT-and-kata.md

@@ -235,7 +235,7 @@ then [Kata-deploy](https://github.com/kata-containers/kata-containers/tree/main/
 is use to install Kata. This will make sure that the correct `agent` version 
 is installed into the rootfs in the steps below.
 
-The following instructions use Debian as the root filesystem with systemd as 
+The following instructions use Ubuntu as the root filesystem with systemd as 
 the init and will add in the `kmod` binary, which is not a standard binary in 
 a Kata rootfs image. The `kmod` binary is necessary to load the Intel® QAT 
 kernel modules when the virtual machine rootfs boots. 
@@ -257,7 +257,7 @@ $ cd $GOPATH
 $ export AGENT_VERSION=$(kata-runtime version | head -n 1 | grep -o "[0-9.]\+")
 $ cd ${OSBUILDER}/rootfs-builder
 $ sudo rm -rf ${ROOTFS_DIR}
-$ script -fec 'sudo -E GOPATH=$GOPATH USE_DOCKER=true SECCOMP=no ./rootfs.sh debian'
+$ script -fec 'sudo -E GOPATH=$GOPATH USE_DOCKER=true SECCOMP=no ./rootfs.sh ubuntu'
 ```
 
 ### Compile Intel® QAT drivers for Kata Containers kernel and add to Kata Containers rootfs

docs/use-cases/using-Intel-SGX-and-kata.md

@@ -1,107 +1,113 @@
 # Kata Containers with SGX
 
-Intel® Software Guard Extensions (SGX) is a set of instructions that increases the security
+Intel Software Guard Extensions (SGX) is a set of instructions that increases the security
 of applications code and data, giving them more protections from disclosure or modification.
 
-> **Note:** At the time of writing this document, SGX patches have not landed on the Linux kernel
-> project, so specific versions for guest and host kernels must be installed to enable SGX.
+This document guides you to run containers with SGX enclaves with Kata Containers in Kubernetes.
 
-## Check if SGX is enabled
+## Preconditions
 
-Run the following command to check if your host supports SGX.
+* Intel SGX capable bare metal nodes
+* Host kernel Linux 5.13 or later with SGX and SGX KVM enabled:
 
 ```sh
-$ grep -o sgx /proc/cpuinfo
+$ grep SGX /boot/config-`uname -r`
+CONFIG_X86_SGX=y
+CONFIG_X86_SGX_KVM=y
 ```
 
-Continue to the following section if the output of the above command is empty,
-otherwise continue to section [Install Guest kernel with SGX support](#install-guest-kernel-with-sgx-support)
+* Kubernetes cluster configured with:
+   * [`kata-deploy`](https://github.com/kata-containers/kata-containers/tree/main/tools/packaging/kata-deploy) based Kata Containers installation
+   * [Intel SGX Kubernetes device plugin](https://github.com/intel/intel-device-plugins-for-kubernetes/tree/main/cmd/sgx_plugin#deploying-with-pre-built-images)
 
-## Install Host kernel with SGX support
+> Note: Kata Containers supports creating VM sandboxes with Intel® SGX enabled
+> using [cloud-hypervisor](https://github.com/cloud-hypervisor/cloud-hypervisor/) VMM only. QEMU support is waiting to get the
+> Intel SGX enabled QEMU upstream release.
 
-The following commands were tested on Fedora 32, they might work on other distros too.
+## Installation
+
+### Kata Containers Guest Kernel
+
+Follow the instructions to [setup](../../tools/packaging/kernel/README.md#setup-kernel-source-code) and [build](../../tools/packaging/kernel/README.md#build-the-kernel) the experimental guest kernel. Then, install as:
 
 ```sh
-$ git clone --depth=1 https://github.com/intel/kvm-sgx
-$ pushd kvm-sgx
-$ cp /boot/config-$(uname -r) .config
-$ yes "" | make oldconfig
-$ # In the following step, enable: INTEL_SGX and INTEL_SGX_VIRTUALIZATION
-$ make menuconfig
-$ make -j$(($(nproc)-1)) bzImage
-$ make -j$(($(nproc)-1)) modules
-$ sudo make modules_install
-$ sudo make install
-$ popd
-$ sudo reboot
+$ sudo cp kata-linux-experimental-*/vmlinux /opt/kata/share/kata-containers/vmlinux.sgx
+$ sudo sed -i 's|vmlinux.container|vmlinux.sgx|g' \
+  /opt/kata/share/defaults/kata-containers/configuration-clh.toml
 ```
 
-> **Notes:**
-> * Run: `mokutil --sb-state` to check whether secure boot is enabled, if so, you will need to sign the kernel.
-> * You'll lose SGX support when a new distro kernel is installed and the system rebooted.
-
-Once you have restarted your system with the new brand Linux Kernel with SGX support, run
-the following command to make sure it's enabled. If the output is empty, go to the BIOS
-setup and enable SGX manually.
-
-```sh
-$ grep -o sgx /proc/cpuinfo
-```
-
-## Install Guest kernel with SGX support
-
-Install the guest kernel in the Kata Containers directory, this way it can be used to run
-Kata Containers.
-
-```sh
-$ curl -LOk https://github.com/devimc/kvm-sgx/releases/download/v0.0.1/kata-virtiofs-sgx.tar.gz
-$ sudo tar -xf kata-virtiofs-sgx.tar.gz -C /usr/share/kata-containers/
-$ sudo sed -i 's|kernel =|kernel = "/usr/share/kata-containers/vmlinux-virtiofs-sgx.container"|g' \
-  /usr/share/defaults/kata-containers/configuration.toml
-```
-
-## Run Kata Containers with SGX enabled
+### Kata Containers Configuration
 
 Before running a Kata Container make sure that your version of `crio` or `containerd`
 supports annotations.
+
 For `containerd` check in `/etc/containerd/config.toml` that the list of `pod_annotations` passed
 to the `sandbox` are: `["io.katacontainers.*", "sgx.intel.com/epc"]`.
 
-> `sgx.yaml`
+## Usage
+
+With the following sample job deployed using `kubectl apply -f`:
+
 ```yaml
-apiVersion: v1
-kind: Pod
+apiVersion: batch/v1
+kind: Job
 metadata:
-  name: sgx
-  annotations:
-    sgx.intel.com/epc: "32Mi"
+  name: oesgx-demo-job
+  labels:
+    jobgroup: oesgx-demo
 spec:
-  terminationGracePeriodSeconds: 0
-  runtimeClassName: kata
-  containers:
-  - name: c1
-    image: busybox
-    command:
-        - sh
-    stdin: true
-    tty: true
-    volumeMounts:
-    - mountPath: /dev/sgx/
-      name: test-volume
-  volumes:
-  - name: test-volume
-    hostPath:
-      path: /dev/sgx/
-      type: Directory
+  template:
+    metadata:
+      labels:
+        jobgroup: oesgx-demo
+    spec:
+      runtimeClassName: kata-clh
+      initContainers:
+        - name: init-sgx
+          image: busybox
+          command: ['sh', '-c', 'mkdir /dev/sgx; ln -s /dev/sgx_enclave /dev/sgx/enclave; ln -s /dev/sgx_provision /dev/sgx/provision']
+          volumeMounts:
+          - mountPath: /dev
+            name: dev-mount
+      restartPolicy: Never
+      containers:
+        -
+          name: eosgx-demo-job-1
+          image: oeciteam/oe-helloworld:latest
+          imagePullPolicy: IfNotPresent
+          securityContext:
+            readOnlyRootFilesystem: true
+            capabilities:
+              add: ["IPC_LOCK"]
+          resources:
+            limits:
+              sgx.intel.com/epc: "512Ki"
+      volumes:
+        - name: dev-mount
+          hostPath:
+            path: /dev
 ```
 
+You'll see the enclave output:
+
 ```sh
-$ kubectl apply -f sgx.yaml
-$ kubectl exec -ti sgx ls /dev/sgx/
-enclave    provision
+$ kubectl logs oesgx-demo-job-wh42g
+Hello world from the enclave
+Enclave called into host to print: Hello World!
 ```
 
-The output of the latest command shouldn't be empty, otherwise check
-your system environment to make sure SGX is fully supported.
+### Notes
 
-[1]: github.com/cloud-hypervisor/cloud-hypervisor/
+* The Kata VM's SGX Encrypted Page Cache (EPC) memory size is based on the sum of `sgx.intel.com/epc`
+resource requests within the pod.
+* `init-sgx` can be removed from the YAML configuration file if the Kata rootfs is modified with the
+necessary udev rules.
+   See the [note on SGX backwards compatibility](https://github.com/intel/intel-device-plugins-for-kubernetes/tree/main/cmd/sgx_plugin#backwards-compatibility-note).
+* Intel SGX DCAP attestation is known to work from Kata sandboxes but it comes with one limitation: If
+the Intel SGX `aesm` daemon runs on the bare metal node and DCAP `out-of-proc` attestation is used,
+containers within the Kata sandbox cannot get the access to the host's `/var/run/aesmd/aesm.sock`
+because socket passthrough is not supported. An alternative is to deploy the `aesm` daemon as a side-car
+container.
+* Projects like [Gramine Shielded Containers (GSC)](https://gramine-gsc.readthedocs.io/en/latest/) are
+also known to work. For GSC specifically, the Kata guest kernel needs to have the `CONFIG_NUMA=y`
+enabled and at least one CPU online when running the GSC container.

docs/use-cases/using-SPDK-vhostuser-and-kata.md

@@ -1,4 +1,4 @@
-# Setup to run SPDK vhost-user devices with Kata Containers and Docker*
+# Setup to run SPDK vhost-user devices with Kata Containers
 
 > **Note:** This guide only applies to QEMU, since the vhost-user storage
 > device is only available for QEMU now. The enablement work on other
@@ -104,7 +104,7 @@ devices:
 
 - `vhost-user-blk`
 - `vhost-user-scsi`
-- `vhost-user-nvme`
+- `vhost-user-nvme` (deprecated from SPDK 21.07 release)
 
 For more information, visit [SPDK](https://spdk.io) and [SPDK vhost-user target](https://spdk.io/doc/vhost.html).
 
@@ -222,26 +222,43 @@ minor `0` should be created for it, in order to be recognized by Kata runtime:
 $ sudo mknod /var/run/kata-containers/vhost-user/block/devices/vhostblk0 b 241 0
 ```
 
-> **Note:** The enablement of vhost-user block device in Kata containers
-> is supported by Kata Containers `1.11.0-alpha1` or newer.
-> Make sure you have updated your Kata containers before evaluation.
-
 ## Launch a Kata container with SPDK vhost-user block device
 
-To use `vhost-user-blk` device, use Docker to pass a host `vhost-user-blk`
-device to the container. In docker, `--device=HOST-DIR:CONTAINER-DIR` is used
+To use `vhost-user-blk` device, use `ctr` to pass a host `vhost-user-blk`
+device to the container. In your `config.json`, you should use `devices`
 to pass a host device to the container.
 
-For example:
+For example (only `vhost-user-blk` listed):
+
+```json
+{
+  "linux": {
+    "devices": [
+      {
+        "path": "/dev/vda",
+        "type": "b",
+        "major": 241,
+        "minor": 0,
+        "fileMode": 420,
+        "uid": 0,
+        "gid": 0
+      }
+    ]
+  }
+}
+```
+
+With `rootfs` provisioned under `bundle` directory, you can run your SPDK container:
 
 ```bash
-$ sudo docker run --runtime kata-runtime --device=/var/run/kata-containers/vhost-user/block/devices/vhostblk0:/dev/vda -it busybox sh
+$ sudo ctr run -d --runtime io.containerd.run.kata.v2 --config bundle/config.json spdk_container
 ```
 
 Example of performing I/O operations on the `vhost-user-blk` device inside
 container:
 
 ```
+$ sudo ctr t exec --exec-id 1 -t spdk_container sh
 / # ls -l /dev/vda
 brw-r--r--    1 root     root      254,   0 Jan 20 03:54 /dev/vda
 / # dd if=/dev/vda of=/tmp/ddtest bs=4k count=20

snap/README.md

@@ -76,7 +76,7 @@ then a new configuration file can be [created](#configure-kata-containers)
 and [configured][7].
 
 [1]: https://docs.snapcraft.io/snaps/intro
-[2]: ../docs/design/architecture.md#root-filesystem-image
+[2]: ../docs/design/architecture/README.md#root-filesystem-image
 [3]: https://docs.snapcraft.io/reference/confinement#classic
 [4]: https://github.com/kata-containers/runtime#configuration
 [5]: https://docs.docker.com/engine/reference/commandline/dockerd

snap/snapcraft.yaml

@@ -59,7 +59,7 @@ parts:
 
       yq_version=3.4.1
       yq_url="https://${yq_pkg}/releases/download/${yq_version}/yq_${goos}_${goarch}"
-      curl -o "${yq_path}" -LSsf "${yq_url}"
+      curl -o "${yq_path}" -L "${yq_url}"
       chmod +x "${yq_path}"
 
       kata_dir=gopath/src/github.com/${SNAPCRAFT_PROJECT_NAME}/${SNAPCRAFT_PROJECT_NAME}
@@ -118,18 +118,19 @@ parts:
       export AGENT_INIT=yes
       export USE_DOCKER=1
       export DEBUG=1
-      case "$(uname -m)" in
-        aarch64)
-          sudo -E PATH=$PATH make initrd DISTRO=alpine
-        ;;
-        ppc64le|s390x)
-          # Cannot use alpine on ppc64le/s390x because it would require a musl agent
-          sudo -E PATH=$PATH make initrd DISTRO=ubuntu
-        ;;
+      arch="$(uname -m)"
+      initrd_distro=$(${yq} r -X ${kata_dir}/versions.yaml assets.initrd.architecture.${arch}.name)
+      image_distro=$(${yq} r -X ${kata_dir}/versions.yaml assets.image.architecture.${arch}.name)
+      case "$arch" in
         x86_64)
           # In some build systems it's impossible to build a rootfs image, try with the initrd image
-          sudo -E PATH=$PATH make image DISTRO=clearlinux || sudo -E PATH=$PATH make initrd DISTRO=alpine
+          sudo -E PATH=$PATH make image DISTRO=${image_distro} || sudo -E PATH=$PATH make initrd DISTRO=${initrd_distro}
         ;;
+
+        aarch64|ppc64le|s390x)
+          sudo -E PATH=$PATH make initrd DISTRO=${initrd_distro}
+        ;;
+
         *) echo "unsupported architecture: $(uname -m)"; exit 1;;
       esac
 
@@ -139,7 +140,7 @@ parts:
       cp kata-containers*.img ${kata_image_dir}
 
   runtime:
-    after: [godeps, image]
+    after: [godeps, image, cloud-hypervisor]
     plugin: nil
     build-attributes: [no-patchelf]
     override-build: |
@@ -185,6 +186,7 @@ parts:
       - flex
     override-build: |
       yq=${SNAPCRAFT_STAGE}/yq
+      export PATH="${PATH}:${SNAPCRAFT_STAGE}"
       export GOPATH=${SNAPCRAFT_STAGE}/gopath
       kata_dir=${GOPATH}/src/github.com/${SNAPCRAFT_PROJECT_NAME}/${SNAPCRAFT_PROJECT_NAME}
       versions_file="${kata_dir}/versions.yaml"
@@ -199,10 +201,17 @@ parts:
       kata_dir=${GOPATH}/src/github.com/${SNAPCRAFT_PROJECT_NAME}/${SNAPCRAFT_PROJECT_NAME}
 
       cd ${kata_dir}/tools/packaging/kernel
+      kernel_dir_prefix="kata-linux-"
 
       # Setup and build kernel
-      ./build-kernel.sh -v ${kernel_version} -d setup
-      kernel_dir_prefix="kata-linux-"
+      if [ "$(uname -m)" = "x86_64" ]; then
+        kernel_version="$(${yq} r $versions_file assets.kernel-experimental.tag)"
+        kernel_version=${kernel_version#v}
+        kernel_dir_prefix="kata-linux-experimental-"
+        ./build-kernel.sh -e -v ${kernel_version} -d setup
+      else
+        ./build-kernel.sh -v ${kernel_version} -d setup
+      fi
       cd ${kernel_dir_prefix}*
       make -j $(($(nproc)-1)) EXTRAVERSION=".container"
 
@@ -327,6 +336,22 @@ parts:
       # Hack: move qemu to /
       "snap/kata-containers/current/": "./"
 
+  cloud-hypervisor:
+    plugin: nil
+    after: [godeps]
+    override-build: |
+      export GOPATH=${SNAPCRAFT_STAGE}/gopath
+      yq=${SNAPCRAFT_STAGE}/yq
+      kata_dir=${GOPATH}/src/github.com/${SNAPCRAFT_PROJECT_NAME}/${SNAPCRAFT_PROJECT_NAME}
+      versions_file="${kata_dir}/versions.yaml"
+      version="$(${yq} r ${versions_file} assets.hypervisor.cloud_hypervisor.version)"
+      url="https://github.com/cloud-hypervisor/cloud-hypervisor/releases/download/${version}"
+      curl -L ${url}/cloud-hypervisor-static -o cloud-hypervisor
+      curl -LO ${url}/clh-remote
+
+      install -D cloud-hypervisor ${SNAPCRAFT_PART_INSTALL}/usr/bin/cloud-hypervisor
+      install -D clh-remote ${SNAPCRAFT_PART_INSTALL}/usr/bin/clh-remote
+
 apps:
   runtime:
     command: usr/bin/kata-runtime

src/agent/Cargo.toml

@@ -5,29 +5,29 @@ authors = ["The Kata Containers community <kata-dev@lists.katacontainers.io>"]
 edition = "2018"
 
 [dependencies]
-oci = { path = "oci" }
-logging = { path = "../../pkg/logging" }
+oci = { path = "../libs/oci" }
 rustjail = { path = "rustjail" }
-protocols = { path = "protocols" }
+protocols = { path = "../libs/protocols" }
 lazy_static = "1.3.0"
 ttrpc = { version = "0.5.0", features = ["async", "protobuf-codec"], default-features = false }
 protobuf = "=2.14.0"
 libc = "0.2.58"
-nix = "0.21.0"
+nix = "0.23.0"
 capctl = "0.2.0"
 serde_json = "1.0.39"
 scan_fmt = "0.2.3"
 scopeguard = "1.0.0"
 thiserror = "1.0.26"
-regex = "1"
+regex = "1.5.4"
+serial_test = "0.5.1"
 
 # Async helpers
 async-trait = "0.1.42"
 async-recursion = "0.3.2"
-futures = "0.3.12"
+futures = "0.3.17"
 
 # Async runtime
-tokio = { version = "1", features = ["full"] }
+tokio = { version = "1.14.0", features = ["full"] }
 tokio-vsock = "0.3.1"
 
 netlink-sys = { version = "0.7.0", features = ["tokio_socket",]}
@@ -35,21 +35,20 @@ rtnetlink = "0.8.0"
 netlink-packet-utils = "0.4.1"
 ipnetwork = "0.17.0"
 
-# slog:
-# - Dynamic keys required to allow HashMap keys to be slog::Serialized.
-# - The 'max_*' features allow changing the log level at runtime
-#   (by stopping the compiler from removing log calls).
-slog = { version = "2.5.2", features = ["dynamic-keys", "max_level_trace", "release_max_level_info"] }
+# Note: this crate sets the slog 'max_*' features which allows the log level
+# to be modified at runtime.
+logging = { path = "../libs/logging" }
+slog = "2.5.2"
 slog-scope = "4.1.2"
 
 # Redirect ttrpc log calls
 slog-stdlog = "4.0.0"
 log = "0.4.11"
 
-prometheus = { version = "0.9.0", features = ["process"] }
-procfs = "0.7.9"
+prometheus = { version = "0.13.0", features = ["process"] }
+procfs = "0.12.0"
 anyhow = "1.0.32"
-cgroups = { package = "cgroups-rs", version = "0.2.5" }
+cgroups = { package = "cgroups-rs", version = "0.2.8" }
 
 # Tracing
 tracing = "0.1.26"
@@ -61,16 +60,18 @@ vsock-exporter = { path = "vsock-exporter" }
 # Configuration
 serde = { version = "1.0.129", features = ["derive"] }
 toml = "0.5.8"
+clap = { version = "3.0.1", features = ["derive"] }
 
 [dev-dependencies]
 tempfile = "3.1.0"
 
 [workspace]
 members = [
-    "oci",
-    "protocols",
     "rustjail",
 ]
 
 [profile.release]
 lto = true
+
+[features]
+seccomp = ["rustjail/seccomp"]

src/agent/Makefile

@@ -27,6 +27,20 @@ COMMIT_MSG = $(if $(COMMIT),$(COMMIT),unknown)
 # Exported to allow cargo to see it
 export VERSION_COMMIT := $(if $(COMMIT),$(VERSION)-$(COMMIT),$(VERSION))
 
+EXTRA_RUSTFEATURES :=
+
+##VAR SECCOMP=yes|no define if agent enables seccomp feature
+SECCOMP := yes
+
+# Enable seccomp feature of rust build
+ifeq ($(SECCOMP),yes)
+    override EXTRA_RUSTFEATURES += seccomp
+endif
+
+ifneq ($(EXTRA_RUSTFEATURES),)
+    override EXTRA_RUSTFEATURES := --features $(EXTRA_RUSTFEATURES)
+endif
+
 include ../../utils.mk
 
 TARGET_PATH = target/$(TRIPLE)/$(BUILD_TYPE)/$(TARGET)
@@ -87,18 +101,20 @@ endef
 ##TARGET default: build code
 default: $(TARGET) show-header
 
-$(TARGET): $(GENERATED_CODE) $(TARGET_PATH)
+$(TARGET): $(GENERATED_CODE) logging-crate-tests $(TARGET_PATH)
+
+logging-crate-tests:
+	make -C $(CWD)/../libs/logging
 
 $(TARGET_PATH): $(SOURCES) | show-summary
-	@RUSTFLAGS="$(EXTRA_RUSTFLAGS) --deny warnings" cargo build --target $(TRIPLE) --$(BUILD_TYPE)
+	@RUSTFLAGS="$(EXTRA_RUSTFLAGS) --deny warnings" cargo build --target $(TRIPLE) --$(BUILD_TYPE) $(EXTRA_RUSTFEATURES)
 
 $(GENERATED_FILES): %: %.in
 	@sed $(foreach r,$(GENERATED_REPLACEMENTS),-e 's|@$r@|$($r)|g') "$<" > "$@"
 
 ##TARGET optimize: optimized  build
 optimize: $(SOURCES) | show-summary show-header
-	@RUSTFLAGS="-C link-arg=-s $(EXTRA_RUSTFLAGS) --deny-warnings" cargo build --target $(TRIPLE) --$(BUILD_TYPE)
-
+	@RUSTFLAGS="-C link-arg=-s $(EXTRA_RUSTFLAGS) --deny warnings" cargo build --target $(TRIPLE) --$(BUILD_TYPE) $(EXTRA_RUSTFEATURES)
 
 ##TARGET clippy: run clippy linter
 clippy: $(GENERATED_CODE)
@@ -127,7 +143,7 @@ vendor:
 
 #TARGET test: run cargo tests
 test:
-	@cargo test --all --target $(TRIPLE) -- --nocapture
+	@cargo test --all --target $(TRIPLE) $(EXTRA_RUSTFEATURES) -- --nocapture
 
 ##TARGET check: run test
 check: clippy format
@@ -192,9 +208,10 @@ codecov-html: check_tarpaulin
 
 .PHONY: \
 	help \
+	logging-crate-tests \
+	optimize \
 	show-header \
 	show-summary \
-	optimize \
 	vendor
 
 ##TARGET generate-protocols: generate/update grpc agent protocols

src/agent/README.md

@@ -1,47 +1,38 @@
-# Kata Agent in Rust
+# Kata Agent
 
-This is a rust version of the [`kata-agent`](https://github.com/kata-containers/agent).
+## Overview
 
-In Denver PTG, [we discussed about re-writing agent in rust](https://etherpad.openstack.org/p/katacontainers-2019-ptg-denver-agenda):
+The Kata agent is a long running process that runs inside the Virtual Machine
+(VM) (also known as the "pod" or "sandbox").
 
-> In general, we all think about re-write agent in rust to reduce the footprint of agent. Moreover, Eric mentioned the possibility to stop using gRPC, which may have some impact on footprint. We may begin to do some POC to show how much we could save by re-writing agent in rust.
+The agent is packaged inside the Kata Containers
+[guest image](../../docs/design/architecture/README.md#guest-image)
+which is used to boot the VM. Once the runtime has launched the configured
+[hypervisor](../../docs/hypervisors.md) to create a new VM, the agent is
+started. From this point on, the agent is responsible for creating and
+managing the life cycle of the containers inside the VM.
 
-After that, we drafted the initial code here, and any contributions are welcome.
+For further details, see the
+[architecture document](../../docs/design/architecture).
 
-## Features
+## Audience
 
-| Feature | Status |
-| :--|:--:|
-| **OCI Behaviors** |
-| create/start containers | :white_check_mark: |
-| signal/wait process     | :white_check_mark: |
-| exec/list process       | :white_check_mark: |
-| I/O stream              | :white_check_mark: |
-| Cgroups                 | :white_check_mark: |
-| Capabilities, `rlimit`, readonly path, masked path, users | :white_check_mark: |
-| container stats (`stats_container`)                     | :white_check_mark: |
-| Hooks                   | :white_check_mark: |
-| **Agent Features & APIs** |
-| run agent as `init` (mount fs, udev, setup `lo`) | :white_check_mark: |
-| block device as root device                      | :white_check_mark: |
-| Health API                                       | :white_check_mark: |
-| network, interface/routes (`update_container`)   | :white_check_mark: |
-| File transfer API (`copy_file`)                  | :white_check_mark: |
-| Device APIs (`reseed_random_device`, , `online_cpu_memory`, `mem_hotplug_probe`, `set_guet_data_time`) | :white_check_mark: |
-| VSOCK support                                    | :white_check_mark: |
-| virtio-serial support                            | :heavy_multiplication_x: |
-| OCI Spec validator                               | :white_check_mark: |
-| **Infrastructures**|
-| Debug Console | :white_check_mark: |
-| Command line  | :white_check_mark: |
-| Tracing       | :heavy_multiplication_x: |
+If you simply wish to use Kata Containers, it is not necessary to understand
+the details of how the agent operates. Please see the
+[installation documentation](../../docs/install) for details of how deploy
+Kata Containers (which will include the Kata agent).
 
-## Getting Started
+The remainder of this document is only useful for developers and testers.
 
-### Build from Source
-The rust-agent needs to be built statically and linked with `musl`
+## Build from Source
 
-> **Note:** skip this step for ppc64le, the build scripts explicitly use gnu for ppc64le.
+Since the agent is written in the Rust language this section assumes the tool
+chain has been installed using standard Rust `rustup` tool.
+
+### Build with musl
+
+If you wish to build the agent with the `musl` C library, you need to run the
+following commands:
 
 ```bash
 $ arch=$(uname -m)
@@ -49,12 +40,15 @@ $ rustup target add "${arch}-unknown-linux-musl"
 $ sudo ln -s /usr/bin/g++ /bin/musl-g++
 ```
 
-ppc64le-only: Manually install `protoc`, e.g.
-```bash
-$ sudo dnf install protobuf-compiler
-```
+> **Note:**
+>
+> It is not currently possible to build using `musl` on ppc64le and s390x
+> since both platforms lack the `musl` target.
+
+### Build the agent binary
+
+The following steps download the Kata Containers source files and build the agent:
 
-Download the source files in the Kata containers repository and build the agent:
 ```bash
 $ GOPATH="${GOPATH:-$HOME/go}"
 $ dir="$GOPATH/src/github.com/kata-containers"
@@ -62,17 +56,60 @@ $ git -C ${dir} clone --depth 1 https://github.com/kata-containers/kata-containe
 $ make -C ${dir}/kata-containers/src/agent
 ```
 
-## Run Kata CI with rust-agent
-   * Firstly, install Kata as noted by ["how to install Kata"](../../docs/install/README.md)
-   * Secondly, build your own Kata initrd/image following the steps in ["how to build your own initrd/image"](../../docs/Developer-Guide.md#create-and-install-rootfs-and-initrd-image).
-notes: Please use your rust agent instead of the go agent when building your initrd/image.
-   * Clone the Kata CI test cases from: https://github.com/kata-containers/tests.git, and then run the CRI test with: 
+## Change the agent API
+
+The Kata runtime communicates with the Kata agent using a ttRPC based API protocol.
+
+This ttRPC API is defined by a set of [protocol buffers files](protocols/protos).
+The protocol files are used to generate the bindings for the following components:
+
+| Component | Language | Generation method `[*]` | Tooling required |
+|-|-|-|-|
+| runtime | Golang | Run, `make generate-protocols` | `protoc` |
+| agent | Rust | Run, `make` |  |
+
+> **Key:**
+>
+> `[*]` - All commands must be run in the agent repository.
+
+If you wish to change the API, these files must be regenerated. Although the
+rust code will be automatically generated by the
+[build script](protocols/build.rs),
+the Golang code generation requires the external `protoc` command to be
+available in `$PATH`.
+
+To install the `protoc` command on a Fedora/CentOS/RHEL system:
 
 ```bash
-$sudo -E PATH=$PATH -E GOPATH=$GOPATH integration/containerd/shimv2/shimv2-tests.sh
+$ sudo dnf install -y protobuf-compiler
 ```
 
-## Mini Benchmark
-The memory of `RssAnon` consumed by the go-agent and rust-agent as below:
-go-agent: about 11M
-rust-agent: about 1.1M
+## Custom guest image and kernel assets
+
+If you wish to develop or test changes to the agent, you will need to create a
+custom guest image using the [osbuilder tool](../../tools/osbuilder). You
+may also wish to create a custom [guest kernel](../../tools/packaging/kernel).
+
+Once created, [configure](../runtime/README.md#configuration) Kata Containers to use
+these custom assets to allow you to test your changes.
+
+> **Note:**
+>
+> To simplify development and testing, you may wish to run the agent
+> [stand alone](#run-the-agent-stand-alone) initially.
+
+## Tracing
+
+For details of tracing the operation of the agent, see the
+[tracing documentation](/docs/tracing.md).
+
+## Run the agent stand alone
+
+Although the agent is designed to run in a VM environment, for development and
+testing purposes it is possible to run it as a normal application.
+
+When run in this way, the agent can be controlled using the low-level Kata
+agent control tool, rather than the Kata runtime.
+
+For further details, see the
+[agent control tool documentation](../tools/agent-ctl/README.md#run-the-tool-and-the-agent-in-the-same-environment).

src/agent/protocols/build.rs

@@ -1,44 +0,0 @@
-// Copyright (c) 2020 Ant Group
-//
-// SPDX-License-Identifier: Apache-2.0
-//
-
-use std::fs;
-use ttrpc_codegen::{Codegen, Customize};
-
-fn main() {
-    let protos = vec![
-        "protos/types.proto",
-        "protos/agent.proto",
-        "protos/health.proto",
-        "protos/google/protobuf/empty.proto",
-        "protos/oci.proto",
-    ];
-
-    Codegen::new()
-        .out_dir("src")
-        .inputs(&protos)
-        .include("protos")
-        .rust_protobuf()
-        .customize(Customize {
-            async_server: true,
-            ..Default::default()
-        })
-        .run()
-        .expect("Gen codes failed.");
-
-    // There is a message named 'Box' in oci.proto
-    // so there is a struct named 'Box', we should replace Box<Self> to ::std::boxed::Box<Self>
-    // to avoid the conflict.
-    replace_text_in_file(
-        "src/oci.rs",
-        "self: Box<Self>",
-        "self: ::std::boxed::Box<Self>",
-    )
-    .unwrap();
-}
-
-fn replace_text_in_file(file_name: &str, from: &str, to: &str) -> Result<(), std::io::Error> {
-    let new_contents = fs::read_to_string(file_name)?.replace(from, to);
-    fs::write(&file_name, new_contents.as_bytes())
-}

src/agent/rustjail/Cargo.toml

@@ -8,10 +8,10 @@ edition = "2018"
 serde = "1.0.91"
 serde_json = "1.0.39"
 serde_derive = "1.0.91"
-oci = { path = "../oci" }
-protocols = { path ="../protocols" }
+oci = { path = "../../libs/oci" }
+protocols = { path ="../../libs/protocols" }
 caps = "0.5.0"
-nix = "0.21.0"
+nix = "0.23.0"
 scopeguard = "1.0.0"
 capctl = "0.2.0"
 lazy_static = "1.3.0"
@@ -19,18 +19,22 @@ libc = "0.2.58"
 protobuf = "=2.14.0"
 slog = "2.5.2"
 slog-scope = "4.1.2"
-scan_fmt = "0.2"
-regex = "1.1"
+scan_fmt = "0.2.6"
+regex = "1.5.4"
 path-absolutize = "1.2.0"
 anyhow = "1.0.32"
-cgroups = { package = "cgroups-rs", version = "0.2.5" }
+cgroups = { package = "cgroups-rs", version = "0.2.8" }
 rlimit = "0.5.3"
 
 tokio = { version = "1.2.0", features = ["sync", "io-util", "process", "time", "macros"] }
-futures = "0.3"
+futures = "0.3.17"
 async-trait = "0.1.31"
 inotify = "0.9.2"
+libseccomp = { version = "0.1.3", optional = true }
 
 [dev-dependencies]
 serial_test = "0.5.0"
 tempfile = "3.1.0"
+
+[features]
+seccomp = ["libseccomp"]

src/agent/rustjail/src/cgroups/fs/mod.rs

@@ -22,7 +22,6 @@ use crate::cgroups::Manager as CgroupManager;
 use crate::container::DEFAULT_DEVICES;
 use anyhow::{anyhow, Context, Result};
 use libc::{self, pid_t};
-use nix::errno::Errno;
 use oci::{
     LinuxBlockIo, LinuxCpu, LinuxDevice, LinuxDeviceCgroup, LinuxHugepageLimit, LinuxMemory,
     LinuxNetwork, LinuxPids, LinuxResources,
@@ -175,7 +174,7 @@ impl CgroupManager for Manager {
                 freezer_controller.freeze()?;
             }
             _ => {
-                return Err(nix::Error::Sys(Errno::EINVAL).into());
+                return Err(anyhow!(nix::Error::EINVAL));
             }
         }
 

src/agent/rustjail/src/container.rs

@@ -25,6 +25,8 @@ use crate::cgroups::mock::Manager as FsManager;
 use crate::cgroups::Manager;
 use crate::log_child;
 use crate::process::Process;
+#[cfg(feature = "seccomp")]
+use crate::seccomp;
 use crate::specconv::CreateOpts;
 use crate::{mount, validator};
 
@@ -151,7 +153,7 @@ lazy_static! {
             },
             LinuxDevice {
                 path: "/dev/full".to_string(),
-                r#type: String::from("c"),
+                r#type: "c".to_string(),
                 major: 1,
                 minor: 7,
                 file_mode: Some(0o666),
@@ -417,7 +419,7 @@ fn do_init_child(cwfd: RawFd) -> Result<()> {
                         ns.r#type.clone(),
                         ns.path.clone()
                     );
-                    log_child!(cfd_log, "error is : {:?}", e.as_errno());
+                    log_child!(cfd_log, "error is : {:?}", e);
                     e
                 })?;
 
@@ -494,7 +496,7 @@ fn do_init_child(cwfd: RawFd) -> Result<()> {
         log_child!(cfd_log, "join namespace {:?}", s);
         sched::setns(fd, s).or_else(|e| {
             if s == CloneFlags::CLONE_NEWUSER {
-                if e.as_errno().unwrap() != Errno::EINVAL {
+                if e != Errno::EINVAL {
                     let _ = write_sync(cwfd, SYNC_FAILED, format!("{:?}", e).as_str());
                     return Err(e);
                 }
@@ -593,11 +595,30 @@ fn do_init_child(cwfd: RawFd) -> Result<()> {
         })?;
     }
 
-    // NoNewPeiviledges, Drop capabilities
+    // NoNewPrivileges
     if oci_process.no_new_privileges {
         capctl::prctl::set_no_new_privs().map_err(|_| anyhow!("cannot set no new privileges"))?;
     }
 
+    // Log unknown seccomp system calls in advance before the log file descriptor closes.
+    #[cfg(feature = "seccomp")]
+    if let Some(ref scmp) = linux.seccomp {
+        if let Some(syscalls) = seccomp::get_unknown_syscalls(scmp) {
+            log_child!(cfd_log, "unknown seccomp system calls: {:?}", syscalls);
+        }
+    }
+
+    // Without NoNewPrivileges, we need to set seccomp
+    // before dropping capabilities because the calling thread
+    // must have the CAP_SYS_ADMIN.
+    #[cfg(feature = "seccomp")]
+    if !oci_process.no_new_privileges {
+        if let Some(ref scmp) = linux.seccomp {
+            seccomp::init_seccomp(scmp)?;
+        }
+    }
+
+    // Drop capabilities
     if oci_process.capabilities.is_some() {
         let c = oci_process.capabilities.as_ref().unwrap();
         capabilities::drop_privileges(cfd_log, c)?;
@@ -623,11 +644,10 @@ fn do_init_child(cwfd: RawFd) -> Result<()> {
 
     // setup the envs
     for e in env.iter() {
-        let v: Vec<&str> = e.splitn(2, '=').collect();
-        if v.len() != 2 {
-            continue;
+        match valid_env(e) {
+            Some((key, value)) => env::set_var(key, value),
+            None => log_child!(cfd_log, "invalid env key-value: {:?}", e),
         }
-        env::set_var(v[0], v[1]);
     }
 
     // set the "HOME" env getting from "/etc/passwd", if
@@ -641,7 +661,7 @@ fn do_init_child(cwfd: RawFd) -> Result<()> {
     let exec_file = Path::new(&args[0]);
     log_child!(cfd_log, "process command: {:?}", &args);
     if !exec_file.exists() {
-        find_file(exec_file).ok_or_else(|| anyhow!("the file {} is not exist", &args[0]))?;
+        find_file(exec_file).ok_or_else(|| anyhow!("the file {} was not found", &args[0]))?;
     }
 
     // notify parent that the child's ready to start
@@ -651,8 +671,8 @@ fn do_init_child(cwfd: RawFd) -> Result<()> {
     let _ = unistd::close(crfd);
     let _ = unistd::close(cwfd);
 
+    unistd::setsid().context("create a new session")?;
     if oci_process.terminal {
-        unistd::setsid()?;
         unsafe {
             libc::ioctl(0, libc::TIOCSCTTY);
         }
@@ -669,6 +689,16 @@ fn do_init_child(cwfd: RawFd) -> Result<()> {
         unistd::read(fd, &mut buf)?;
     }
 
+    // With NoNewPrivileges, we should set seccomp as close to
+    // do_exec as possible in order to reduce the amount of
+    // system calls in the seccomp profiles.
+    #[cfg(feature = "seccomp")]
+    if oci_process.no_new_privileges {
+        if let Some(ref scmp) = linux.seccomp {
+            seccomp::init_seccomp(scmp)?;
+        }
+    }
+
     do_exec(&args);
 }
 
@@ -972,8 +1002,6 @@ impl BaseContainer for LinuxContainer {
 
         info!(logger, "entered namespaces!");
 
-        self.created = SystemTime::now();
-
         if p.init {
             let spec = self.config.spec.as_mut().unwrap();
             update_namespaces(&self.logger, spec, p.pid)?;
@@ -1088,10 +1116,8 @@ fn do_exec(args: &[String]) -> ! {
         .collect();
 
     let _ = unistd::execvp(p.as_c_str(), &sa).map_err(|e| match e {
-        nix::Error::Sys(errno) => {
-            std::process::exit(errno as i32);
-        }
-        _ => std::process::exit(-2),
+        nix::Error::UnknownErrno => std::process::exit(-2),
+        _ => std::process::exit(e as i32),
     });
 
     unreachable!()
@@ -1137,7 +1163,7 @@ fn get_pid_namespace(logger: &Logger, linux: &Linux) -> Result<Option<RawFd>> {
                         ns.r#type.clone(),
                         ns.path.clone()
                     );
-                    error!(logger, "error is : {:?}", e.as_errno());
+                    error!(logger, "error is : {:?}", e);
 
                     e
                 })?;
@@ -1370,13 +1396,13 @@ impl LinuxContainer {
         .context(format!("cannot change onwer of container {} root", id))?;
 
         if config.spec.is_none() {
-            return Err(nix::Error::Sys(Errno::EINVAL).into());
+            return Err(anyhow!(nix::Error::EINVAL));
         }
 
         let spec = config.spec.as_ref().unwrap();
 
         if spec.linux.is_none() {
-            return Err(nix::Error::Sys(Errno::EINVAL).into());
+            return Err(anyhow!(nix::Error::EINVAL));
         }
 
         let linux = spec.linux.as_ref().unwrap();
@@ -1453,7 +1479,7 @@ async fn execute_hook(logger: &Logger, h: &Hook, st: &OCIState) -> Result<()> {
     let binary = PathBuf::from(h.path.as_str());
     let path = binary.canonicalize()?;
     if !path.exists() {
-        return Err(anyhow!(nix::Error::from_errno(Errno::EINVAL)));
+        return Err(anyhow!(nix::Error::EINVAL));
     }
 
     let args = h.args.clone();
@@ -1522,7 +1548,7 @@ async fn execute_hook(logger: &Logger, h: &Hook, st: &OCIState) -> Result<()> {
 
                 if code != 0 {
                     error!(logger, "hook {} exit status is {}", &path, code);
-                    return Err(anyhow!(nix::Error::from_errno(Errno::UnknownErrno)));
+                    return Err(anyhow!(nix::Error::UnknownErrno));
                 }
 
                 debug!(logger, "hook {} exit status is 0", &path);
@@ -1538,10 +1564,34 @@ async fn execute_hook(logger: &Logger, h: &Hook, st: &OCIState) -> Result<()> {
 
     match tokio::time::timeout(Duration::new(timeout, 0), join_handle).await {
         Ok(r) => r.unwrap(),
-        Err(_) => Err(anyhow!(nix::Error::from_errno(Errno::ETIMEDOUT))),
+        Err(_) => Err(anyhow!(nix::Error::ETIMEDOUT)),
     }
 }
 
+// valid environment variables according to https://doc.rust-lang.org/std/env/fn.set_var.html#panics
+fn valid_env(e: &str) -> Option<(&str, &str)> {
+    // wherther key or value will contain NULL char.
+    if e.as_bytes().contains(&b'\0') {
+        return None;
+    }
+
+    let v: Vec<&str> = e.splitn(2, '=').collect();
+
+    // key can't hold an `equal` sign, but value can
+    if v.len() != 2 {
+        return None;
+    }
+
+    let (key, value) = (v[0].trim(), v[1].trim());
+
+    // key can't be empty
+    if key.is_empty() {
+        return None;
+    }
+
+    Some((key, value))
+}
+
 #[cfg(test)]
 mod tests {
     use super::*;
@@ -1620,7 +1670,7 @@ mod tests {
         )
         .await;
 
-        let expected_err = nix::Error::from_errno(Errno::ETIMEDOUT);
+        let expected_err = nix::Error::ETIMEDOUT;
         assert_eq!(
             res.unwrap_err().downcast::<nix::Error>().unwrap(),
             expected_err
@@ -1965,4 +2015,49 @@ mod tests {
         let ret = do_init_child(std::io::stdin().as_raw_fd());
         assert!(ret.is_err(), "Expecting Err, Got {:?}", ret);
     }
+
+    #[test]
+    fn test_valid_env() {
+        let env = valid_env("a=b=c");
+        assert_eq!(Some(("a", "b=c")), env);
+
+        let env = valid_env("a=b");
+        assert_eq!(Some(("a", "b")), env);
+        let env = valid_env("a =b");
+        assert_eq!(Some(("a", "b")), env);
+
+        let env = valid_env(" a =b");
+        assert_eq!(Some(("a", "b")), env);
+
+        let env = valid_env("a= b");
+        assert_eq!(Some(("a", "b")), env);
+
+        let env = valid_env("a=b ");
+        assert_eq!(Some(("a", "b")), env);
+        let env = valid_env("a=b c ");
+        assert_eq!(Some(("a", "b c")), env);
+
+        let env = valid_env("=b");
+        assert_eq!(None, env);
+
+        let env = valid_env("a=");
+        assert_eq!(Some(("a", "")), env);
+
+        let env = valid_env("a==");
+        assert_eq!(Some(("a", "=")), env);
+
+        let env = valid_env("a");
+        assert_eq!(None, env);
+
+        let invalid_str = vec![97, b'\0', 98];
+        let invalid_string = std::str::from_utf8(&invalid_str).unwrap();
+
+        let invalid_env = format!("{}=value", invalid_string);
+        let env = valid_env(&invalid_env);
+        assert_eq!(None, env);
+
+        let invalid_env = format!("key={}", invalid_string);
+        let env = valid_env(&invalid_env);
+        assert_eq!(None, env);
+    }
 }

src/agent/rustjail/src/lib.rs

@@ -34,6 +34,8 @@ pub mod container;
 pub mod mount;
 pub mod pipestream;
 pub mod process;
+#[cfg(feature = "seccomp")]
+pub mod seccomp;
 pub mod specconv;
 pub mod sync;
 pub mod sync_with_async;

src/agent/rustjail/src/mount.rs

@@ -3,9 +3,8 @@
 // SPDX-License-Identifier: Apache-2.0
 //
 
-use anyhow::{anyhow, bail, Context, Result};
+use anyhow::{anyhow, Context, Result};
 use libc::uid_t;
-use nix::errno::Errno;
 use nix::fcntl::{self, OFlag};
 #[cfg(not(test))]
 use nix::mount;
@@ -19,7 +18,7 @@ use std::fs::{self, OpenOptions};
 use std::mem::MaybeUninit;
 use std::os::unix;
 use std::os::unix::io::RawFd;
-use std::path::{Path, PathBuf};
+use std::path::{Component, Path, PathBuf};
 
 use path_absolutize::*;
 use std::fs::File;
@@ -35,17 +34,9 @@ use crate::log_child;
 // struct is populated from the content in the /proc/<pid>/mountinfo file.
 #[derive(std::fmt::Debug)]
 pub struct Info {
-    id: i32,
-    parent: i32,
-    major: i32,
-    minor: i32,
-    root: String,
     mount_point: String,
-    opts: String,
     optional: String,
     fstype: String,
-    source: String,
-    vfs_opts: String,
 }
 
 const MOUNTINFOFORMAT: &str = "{d} {d} {d}:{d} {} {} {} {}";
@@ -112,6 +103,7 @@ lazy_static! {
 }
 
 #[inline(always)]
+#[cfg(not(test))]
 pub fn mount<
     P1: ?Sized + NixPath,
     P2: ?Sized + NixPath,
@@ -124,21 +116,42 @@ pub fn mount<
     flags: MsFlags,
     data: Option<&P4>,
 ) -> std::result::Result<(), nix::Error> {
-    #[cfg(not(test))]
-    return mount::mount(source, target, fstype, flags, data);
-    #[cfg(test)]
-    return Ok(());
+    mount::mount(source, target, fstype, flags, data)
 }
 
 #[inline(always)]
+#[cfg(test)]
+pub fn mount<
+    P1: ?Sized + NixPath,
+    P2: ?Sized + NixPath,
+    P3: ?Sized + NixPath,
+    P4: ?Sized + NixPath,
+>(
+    _source: Option<&P1>,
+    _target: &P2,
+    _fstype: Option<&P3>,
+    _flags: MsFlags,
+    _data: Option<&P4>,
+) -> std::result::Result<(), nix::Error> {
+    Ok(())
+}
+
+#[inline(always)]
+#[cfg(not(test))]
 pub fn umount2<P: ?Sized + NixPath>(
     target: &P,
     flags: MntFlags,
 ) -> std::result::Result<(), nix::Error> {
-    #[cfg(not(test))]
-    return mount::umount2(target, flags);
-    #[cfg(test)]
-    return Ok(());
+    mount::umount2(target, flags)
+}
+
+#[inline(always)]
+#[cfg(test)]
+pub fn umount2<P: ?Sized + NixPath>(
+    _target: &P,
+    _flags: MntFlags,
+) -> std::result::Result<(), nix::Error> {
+    Ok(())
 }
 
 pub fn init_rootfs(
@@ -450,14 +463,20 @@ fn mount_cgroups(
     Ok(())
 }
 
+#[cfg(not(test))]
 fn pivot_root<P1: ?Sized + NixPath, P2: ?Sized + NixPath>(
     new_root: &P1,
     put_old: &P2,
 ) -> anyhow::Result<(), nix::Error> {
-    #[cfg(not(test))]
-    return unistd::pivot_root(new_root, put_old);
-    #[cfg(test)]
-    return Ok(());
+    unistd::pivot_root(new_root, put_old)
+}
+
+#[cfg(test)]
+fn pivot_root<P1: ?Sized + NixPath, P2: ?Sized + NixPath>(
+    _new_root: &P1,
+    _put_old: &P2,
+) -> anyhow::Result<(), nix::Error> {
+    Ok(())
 }
 
 pub fn pivot_rootfs<P: ?Sized + NixPath + std::fmt::Debug>(path: &P) -> Result<()> {
@@ -535,7 +554,20 @@ fn parse_mount_table() -> Result<Vec<Info>> {
     for (_index, line) in reader.lines().enumerate() {
         let line = line?;
 
-        let (id, parent, major, minor, root, mount_point, opts, optional) = scan_fmt!(
+        //Example mountinfo format:
+        // id
+        // |  / parent
+        // |  |   / major:minor
+        // |  |   |   / root
+        // |  |   |   |  / mount_point
+        // |  |   |   |  |        / opts
+        // |  |   |   |  |        |                           / optional
+        // |  |   |   |  |        |                           |          / fstype
+        // |  |   |   |  |        |                           |          |     / source
+        // |  |   |   |  |        |                           |          |     |      / vfs_opts
+        // 22 96 0:21 / /sys rw,nosuid,nodev,noexec,relatime shared:2 - sysfs sysfs rw,seclabel
+
+        let (_id, _parent, _major, _minor, _root, mount_point, _opts, optional) = scan_fmt!(
             &line,
             MOUNTINFOFORMAT,
             i32,
@@ -550,7 +582,7 @@ fn parse_mount_table() -> Result<Vec<Info>> {
 
         let fields: Vec<&str> = line.split(" - ").collect();
         if fields.len() == 2 {
-            let (fstype, source, vfs_opts) =
+            let (fstype, _source, _vfs_opts) =
                 scan_fmt!(fields[1], "{} {} {}", String, String, String)?;
 
             let mut optional_new = String::new();
@@ -559,17 +591,9 @@ fn parse_mount_table() -> Result<Vec<Info>> {
             }
 
             let info = Info {
-                id,
-                parent,
-                major,
-                minor,
-                root,
                 mount_point,
-                opts,
                 optional: optional_new,
                 fstype,
-                source,
-                vfs_opts,
             };
 
             infos.push(info);
@@ -582,11 +606,15 @@ fn parse_mount_table() -> Result<Vec<Info>> {
 }
 
 #[inline(always)]
+#[cfg(not(test))]
 fn chroot<P: ?Sized + NixPath>(path: &P) -> Result<(), nix::Error> {
-    #[cfg(not(test))]
-    return unistd::chroot(path);
-    #[cfg(test)]
-    return Ok(());
+    unistd::chroot(path)
+}
+
+#[inline(always)]
+#[cfg(test)]
+fn chroot<P: ?Sized + NixPath>(_path: &P) -> Result<(), nix::Error> {
+    Ok(())
 }
 
 pub fn ms_move_root(rootfs: &str) -> Result<bool> {
@@ -623,7 +651,7 @@ pub fn ms_move_root(rootfs: &str) -> Result<bool> {
             None::<&str>,
         )?;
         umount2(abs_mount_point, MntFlags::MNT_DETACH).or_else(|e| {
-            if e.ne(&nix::Error::from(Errno::EINVAL)) && e.ne(&nix::Error::from(Errno::EPERM)) {
+            if e.ne(&nix::Error::EINVAL) && e.ne(&nix::Error::EPERM) {
                 return Err(anyhow!(e));
             }
 
@@ -745,7 +773,7 @@ fn mount_from(
         let _ = fs::create_dir_all(&dir).map_err(|e| {
             log_child!(
                 cfd_log,
-                "creat dir {}: {}",
+                "create dir {}: {}",
                 dir.to_str().unwrap(),
                 e.to_string()
             )
@@ -766,14 +794,8 @@ fn mount_from(
         }
     };
 
-    let _ = stat::stat(dest.as_str()).map_err(|e| {
-        log_child!(
-            cfd_log,
-            "dest stat error. {}: {:?}",
-            dest.as_str(),
-            e.as_errno()
-        )
-    });
+    let _ = stat::stat(dest.as_str())
+        .map_err(|e| log_child!(cfd_log, "dest stat error. {}: {:?}", dest.as_str(), e));
 
     mount(
         Some(src.as_str()),
@@ -783,7 +805,7 @@ fn mount_from(
         Some(d.as_str()),
     )
     .map_err(|e| {
-        log_child!(cfd_log, "mount error: {:?}", e.as_errno());
+        log_child!(cfd_log, "mount error: {:?}", e);
         e
     })?;
 
@@ -805,7 +827,7 @@ fn mount_from(
             None::<&str>,
         )
         .map_err(|e| {
-            log_child!(cfd_log, "remout {}: {:?}", dest.as_str(), e.as_errno());
+            log_child!(cfd_log, "remout {}: {:?}", dest.as_str(), e);
             e
         })?;
     }
@@ -828,18 +850,35 @@ fn default_symlinks() -> Result<()> {
     }
     Ok(())
 }
+
+fn dev_rel_path(path: &str) -> Option<&Path> {
+    let path = Path::new(path);
+
+    if !path.starts_with("/dev")
+        || path == Path::new("/dev")
+        || path.components().any(|c| c == Component::ParentDir)
+    {
+        return None;
+    }
+    path.strip_prefix("/").ok()
+}
+
 fn create_devices(devices: &[LinuxDevice], bind: bool) -> Result<()> {
-    let op: fn(&LinuxDevice) -> Result<()> = if bind { bind_dev } else { mknod_dev };
+    let op: fn(&LinuxDevice, &Path) -> Result<()> = if bind { bind_dev } else { mknod_dev };
     let old = stat::umask(Mode::from_bits_truncate(0o000));
     for dev in DEFAULT_DEVICES.iter() {
-        op(dev)?;
+        let path = Path::new(&dev.path[1..]);
+        op(dev, path).context(format!("Creating container device {:?}", dev))?;
     }
     for dev in devices {
-        if !dev.path.starts_with("/dev") || dev.path.contains("..") {
+        let path = dev_rel_path(&dev.path).ok_or_else(|| {
             let msg = format!("{} is not a valid device path", dev.path);
-            bail!(anyhow!(msg));
+            anyhow!(msg)
+        })?;
+        if let Some(dir) = path.parent() {
+            fs::create_dir_all(dir).context(format!("Creating container device {:?}", dev))?;
         }
-        op(dev)?;
+        op(dev, path).context(format!("Creating container device {:?}", dev))?;
     }
     stat::umask(old);
     Ok(())
@@ -861,21 +900,21 @@ lazy_static! {
     };
 }
 
-fn mknod_dev(dev: &LinuxDevice) -> Result<()> {
+fn mknod_dev(dev: &LinuxDevice, relpath: &Path) -> Result<()> {
     let f = match LINUXDEVICETYPE.get(dev.r#type.as_str()) {
         Some(v) => v,
         None => return Err(anyhow!("invalid spec".to_string())),
     };
 
     stat::mknod(
-        &dev.path[1..],
+        relpath,
         *f,
         Mode::from_bits_truncate(dev.file_mode.unwrap_or(0)),
         nix::sys::stat::makedev(dev.major as u64, dev.minor as u64),
     )?;
 
     unistd::chown(
-        &dev.path[1..],
+        relpath,
         Some(Uid::from_raw(dev.uid.unwrap_or(0) as uid_t)),
         Some(Gid::from_raw(dev.gid.unwrap_or(0) as uid_t)),
     )?;
@@ -883,9 +922,9 @@ fn mknod_dev(dev: &LinuxDevice) -> Result<()> {
     Ok(())
 }
 
-fn bind_dev(dev: &LinuxDevice) -> Result<()> {
+fn bind_dev(dev: &LinuxDevice, relpath: &Path) -> Result<()> {
     let fd = fcntl::open(
-        &dev.path[1..],
+        relpath,
         OFlag::O_RDWR | OFlag::O_CREAT,
         Mode::from_bits_truncate(0o644),
     )?;
@@ -894,7 +933,7 @@ fn bind_dev(dev: &LinuxDevice) -> Result<()> {
 
     mount(
         Some(&*dev.path),
-        &dev.path[1..],
+        relpath,
         None::<&str>,
         MsFlags::MS_BIND,
         None::<&str>,
@@ -957,7 +996,7 @@ pub fn finish_rootfs(cfd_log: RawFd, spec: &Spec, process: &Process) -> Result<(
 
 fn mask_path(path: &str) -> Result<()> {
     if !path.starts_with('/') || path.contains("..") {
-        return Err(nix::Error::Sys(Errno::EINVAL).into());
+        return Err(anyhow!(nix::Error::EINVAL));
     }
 
     match mount(
@@ -967,49 +1006,30 @@ fn mask_path(path: &str) -> Result<()> {
         MsFlags::MS_BIND,
         None::<&str>,
     ) {
-        Err(nix::Error::Sys(e)) => {
-            if e != Errno::ENOENT && e != Errno::ENOTDIR {
-                //info!("{}: {}", path, e.desc());
-                return Err(nix::Error::Sys(e).into());
-            }
-        }
-
-        Err(e) => {
-            return Err(e.into());
-        }
-
-        Ok(_) => {}
+        Err(e) => match e {
+            nix::Error::ENOENT | nix::Error::ENOTDIR => Ok(()),
+            _ => Err(e.into()),
+        },
+        Ok(_) => Ok(()),
     }
-
-    Ok(())
 }
 
 fn readonly_path(path: &str) -> Result<()> {
     if !path.starts_with('/') || path.contains("..") {
-        return Err(nix::Error::Sys(Errno::EINVAL).into());
+        return Err(anyhow!(nix::Error::EINVAL));
     }
 
-    match mount(
+    if let Err(e) = mount(
         Some(&path[1..]),
         path,
         None::<&str>,
         MsFlags::MS_BIND | MsFlags::MS_REC,
         None::<&str>,
     ) {
-        Err(nix::Error::Sys(e)) => {
-            if e == Errno::ENOENT {
-                return Ok(());
-            } else {
-                //info!("{}: {}", path, e.desc());
-                return Err(nix::Error::Sys(e).into());
-            }
-        }
-
-        Err(e) => {
-            return Err(e.into());
-        }
-
-        Ok(_) => {}
+        match e {
+            nix::Error::ENOENT => return Ok(()),
+            _ => return Err(e.into()),
+        };
     }
 
     mount(
@@ -1258,11 +1278,12 @@ mod tests {
             uid: Some(unistd::getuid().as_raw()),
             gid: Some(unistd::getgid().as_raw()),
         };
+        let path = Path::new("fifo");
 
-        let ret = mknod_dev(&dev);
+        let ret = mknod_dev(&dev, path);
         assert!(ret.is_ok(), "Should pass. Got: {:?}", ret);
 
-        let ret = stat::stat("fifo");
+        let ret = stat::stat(path);
         assert!(ret.is_ok(), "Should pass. Got: {:?}", ret);
     }
     #[test]
@@ -1379,4 +1400,26 @@ mod tests {
             assert!(result == t.result, "{}", msg);
         }
     }
+
+    #[test]
+    fn test_dev_rel_path() {
+        // Valid device paths
+        assert_eq!(dev_rel_path("/dev/sda").unwrap(), Path::new("dev/sda"));
+        assert_eq!(dev_rel_path("//dev/sda").unwrap(), Path::new("dev/sda"));
+        assert_eq!(
+            dev_rel_path("/dev/vfio/99").unwrap(),
+            Path::new("dev/vfio/99")
+        );
+        assert_eq!(dev_rel_path("/dev/...").unwrap(), Path::new("dev/..."));
+        assert_eq!(dev_rel_path("/dev/a..b").unwrap(), Path::new("dev/a..b"));
+        assert_eq!(dev_rel_path("/dev//foo").unwrap(), Path::new("dev/foo"));
+
+        // Bad device paths
+        assert!(dev_rel_path("/devfoo").is_none());
+        assert!(dev_rel_path("/etc/passwd").is_none());
+        assert!(dev_rel_path("/dev/../etc/passwd").is_none());
+        assert!(dev_rel_path("dev/foo").is_none());
+        assert!(dev_rel_path("").is_none());
+        assert!(dev_rel_path("/dev").is_none());
+    }
 }

src/agent/rustjail/src/pipestream.rs

@@ -30,7 +30,7 @@ impl io::Read for &StreamFd {
     fn read(&mut self, buf: &mut [u8]) -> io::Result<usize> {
         match unistd::read(self.0, buf) {
             Ok(l) => Ok(l),
-            Err(e) => Err(e.as_errno().unwrap().into()),
+            Err(e) => Err(e.into()),
         }
     }
 }
@@ -39,7 +39,7 @@ impl io::Write for &StreamFd {
     fn write(&mut self, buf: &[u8]) -> io::Result<usize> {
         match unistd::write(self.0, buf) {
             Ok(l) => Ok(l),
-            Err(e) => Err(e.as_errno().unwrap().into()),
+            Err(e) => Err(e.into()),
         }
     }
 
@@ -52,7 +52,7 @@ impl StreamFd {
     fn close(&mut self) -> io::Result<()> {
         match unistd::close(self.0) {
             Ok(()) => Ok(()),
-            Err(e) => Err(e.as_errno().unwrap().into()),
+            Err(e) => Err(e.into()),
         }
     }
 }

src/agent/rustjail/src/process.rs

@@ -24,6 +24,16 @@ use tokio::io::{split, ReadHalf, WriteHalf};
 use tokio::sync::Mutex;
 use tokio::sync::Notify;
 
+macro_rules! close_process_stream {
+    ($self: ident, $stream:ident, $stream_type: ident) => {
+        if $self.$stream.is_some() {
+            $self.close_stream(StreamType::$stream_type);
+            let _ = unistd::close($self.$stream.unwrap());
+            $self.$stream = None;
+        }
+    };
+}
+
 #[derive(Debug, PartialEq, Eq, Hash, Clone)]
 pub enum StreamType {
     Stdin,
@@ -147,6 +157,22 @@ impl Process {
         notify.notify_one();
     }
 
+    pub fn close_stdin(&mut self) {
+        close_process_stream!(self, term_master, TermMaster);
+        close_process_stream!(self, parent_stdin, ParentStdin);
+
+        self.notify_term_close();
+    }
+
+    pub fn cleanup_process_stream(&mut self) {
+        close_process_stream!(self, parent_stdin, ParentStdin);
+        close_process_stream!(self, parent_stdout, ParentStdout);
+        close_process_stream!(self, parent_stderr, ParentStderr);
+        close_process_stream!(self, term_master, TermMaster);
+
+        self.notify_term_close();
+    }
+
     fn get_fd(&self, stream_type: &StreamType) -> Option<RawFd> {
         match stream_type {
             StreamType::Stdin => self.stdin,

src/agent/rustjail/src/seccomp.rs

@@ -0,0 +1,272 @@
+// Copyright 2021 Sony Group Corporation
+//
+// SPDX-License-Identifier: Apache-2.0
+//
+
+use anyhow::{anyhow, Result};
+use libseccomp::*;
+use oci::{LinuxSeccomp, LinuxSeccompArg};
+use std::str::FromStr;
+
+fn get_filter_attr_from_flag(flag: &str) -> Result<ScmpFilterAttr> {
+    match flag {
+        "SECCOMP_FILTER_FLAG_TSYNC" => Ok(ScmpFilterAttr::CtlTsync),
+        "SECCOMP_FILTER_FLAG_LOG" => Ok(ScmpFilterAttr::CtlLog),
+        "SECCOMP_FILTER_FLAG_SPEC_ALLOW" => Ok(ScmpFilterAttr::CtlSsb),
+        _ => Err(anyhow!("Invalid seccomp flag")),
+    }
+}
+
+// get_rule_conditions gets rule conditions for a system call from the args.
+fn get_rule_conditions(args: &[LinuxSeccompArg]) -> Result<Vec<ScmpArgCompare>> {
+    let mut conditions: Vec<ScmpArgCompare> = Vec::new();
+
+    for arg in args {
+        if arg.op.is_empty() {
+            return Err(anyhow!("seccomp opreator is required"));
+        }
+
+        let cond = ScmpArgCompare::new(
+            arg.index,
+            ScmpCompareOp::from_str(&arg.op)?,
+            arg.value,
+            Some(arg.value_two),
+        );
+
+        conditions.push(cond);
+    }
+
+    Ok(conditions)
+}
+
+pub fn get_unknown_syscalls(scmp: &LinuxSeccomp) -> Option<Vec<String>> {
+    let mut unknown_syscalls: Vec<String> = Vec::new();
+
+    for syscall in &scmp.syscalls {
+        for name in &syscall.names {
+            if get_syscall_from_name(name, None).is_err() {
+                unknown_syscalls.push(name.to_string());
+            }
+        }
+    }
+
+    if unknown_syscalls.is_empty() {
+        None
+    } else {
+        Some(unknown_syscalls)
+    }
+}
+
+// init_seccomp creates a seccomp filter and loads it for the current process
+// including all the child processes.
+pub fn init_seccomp(scmp: &LinuxSeccomp) -> Result<()> {
+    let def_action = ScmpAction::from_str(scmp.default_action.as_str(), Some(libc::EPERM as u32))?;
+
+    // Create a new filter context
+    let mut filter = ScmpFilterContext::new_filter(def_action)?;
+
+    // Add extra architectures
+    for arch in &scmp.architectures {
+        let scmp_arch = ScmpArch::from_str(arch)?;
+        filter.add_arch(scmp_arch)?;
+    }
+
+    // Unset no new privileges bit
+    filter.set_no_new_privs_bit(false)?;
+
+    // Add a rule for each system call
+    for syscall in &scmp.syscalls {
+        if syscall.names.is_empty() {
+            return Err(anyhow!("syscall name is required"));
+        }
+
+        let action = ScmpAction::from_str(&syscall.action, Some(syscall.errno_ret))?;
+        if action == def_action {
+            continue;
+        }
+
+        for name in &syscall.names {
+            let syscall_num = match get_syscall_from_name(name, None) {
+                Ok(num) => num,
+                Err(_) => {
+                    // If we cannot resolve the given system call, we assume it is not supported
+                    // by the kernel. Hence, we skip it without generating an error.
+                    continue;
+                }
+            };
+
+            if syscall.args.is_empty() {
+                filter.add_rule(action, syscall_num, None)?;
+            } else {
+                let conditions = get_rule_conditions(&syscall.args)?;
+                filter.add_rule(action, syscall_num, Some(&conditions))?;
+            }
+        }
+    }
+
+    // Set filter attributes for each seccomp flag
+    for flag in &scmp.flags {
+        let scmp_attr = get_filter_attr_from_flag(flag)?;
+        filter.set_filter_attr(scmp_attr, 1)?;
+    }
+
+    // Load the filter
+    filter.load()?;
+
+    Ok(())
+}
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+    use crate::skip_if_not_root;
+    use libc::{dup3, process_vm_readv, EPERM, O_CLOEXEC};
+    use std::io::Error;
+    use std::ptr::null;
+
+    macro_rules! syscall_assert {
+        ($e1: expr, $e2: expr) => {
+            let mut errno: i32 = 0;
+            if $e1 < 0 {
+                errno = -Error::last_os_error().raw_os_error().unwrap();
+            }
+            assert_eq!(errno, $e2);
+        };
+    }
+
+    const TEST_DATA: &str = r#"{
+          "defaultAction": "SCMP_ACT_ALLOW",
+          "architectures": [
+          ],
+          "flags": [
+              "SECCOMP_FILTER_FLAG_LOG"
+          ],
+          "syscalls": [
+              {
+                 "names": [
+                      "dup3",
+                      "invalid_syscall1",
+                      "invalid_syscall2"
+                  ],
+                  "action": "SCMP_ACT_ERRNO"
+              },
+              {
+                 "names": [
+                      "process_vm_readv"
+                  ],
+                  "action": "SCMP_ACT_ERRNO",
+                  "errnoRet": 111,
+                  "args": [
+                      {
+                          "index": 0,
+                          "value": 10,
+                          "op": "SCMP_CMP_EQ"
+                      }
+                  ]
+              },
+              {
+                 "names": [
+                      "process_vm_readv"
+                  ],
+                  "action": "SCMP_ACT_ERRNO",
+                  "errnoRet": 111,
+                  "args": [
+                      {
+                          "index": 0,
+                          "value": 20,
+                          "op": "SCMP_CMP_EQ"
+                      }
+                  ]
+              },
+              {
+                 "names": [
+                      "process_vm_readv"
+                  ],
+                  "action": "SCMP_ACT_ERRNO",
+                  "errnoRet": 222,
+                  "args": [
+                      {
+                          "index": 0,
+                          "value": 30,
+                          "op": "SCMP_CMP_EQ"
+                      },
+                      {
+                          "index": 2,
+                          "value": 40,
+                          "op": "SCMP_CMP_EQ"
+                      }
+                  ]
+              }
+          ]
+      }"#;
+
+    #[test]
+    fn test_get_filter_attr_from_flag() {
+        skip_if_not_root!();
+
+        assert_eq!(
+            get_filter_attr_from_flag("SECCOMP_FILTER_FLAG_TSYNC").unwrap(),
+            ScmpFilterAttr::CtlTsync
+        );
+
+        assert_eq!(get_filter_attr_from_flag("ERROR").is_err(), true);
+    }
+
+    #[test]
+    fn test_get_unknown_syscalls() {
+        let scmp: oci::LinuxSeccomp = serde_json::from_str(TEST_DATA).unwrap();
+        let syscalls = get_unknown_syscalls(&scmp).unwrap();
+
+        assert_eq!(syscalls, vec!["invalid_syscall1", "invalid_syscall2"]);
+    }
+
+    #[test]
+    fn test_init_seccomp() {
+        skip_if_not_root!();
+
+        let mut scmp: oci::LinuxSeccomp = serde_json::from_str(TEST_DATA).unwrap();
+        let mut arch: Vec<oci::Arch>;
+
+        if cfg!(target_endian = "little") {
+            // For little-endian architectures
+            arch = vec![
+                "SCMP_ARCH_X86".to_string(),
+                "SCMP_ARCH_X32".to_string(),
+                "SCMP_ARCH_X86_64".to_string(),
+                "SCMP_ARCH_AARCH64".to_string(),
+                "SCMP_ARCH_ARM".to_string(),
+                "SCMP_ARCH_PPC64LE".to_string(),
+            ];
+        } else {
+            // For big-endian architectures
+            arch = vec!["SCMP_ARCH_S390X".to_string()];
+        }
+
+        scmp.architectures.append(&mut arch);
+
+        init_seccomp(&scmp).unwrap();
+
+        // Basic syscall with simple rule
+        syscall_assert!(unsafe { dup3(0, 1, O_CLOEXEC) }, -EPERM);
+
+        // Syscall with permitted arguments
+        syscall_assert!(unsafe { process_vm_readv(1, null(), 0, null(), 0, 0) }, 0);
+
+        // Multiple arguments with OR rules with ERRNO
+        syscall_assert!(
+            unsafe { process_vm_readv(10, null(), 0, null(), 0, 0) },
+            -111
+        );
+        syscall_assert!(
+            unsafe { process_vm_readv(20, null(), 0, null(), 0, 0) },
+            -111
+        );
+
+        // Multiple arguments with AND rules with ERRNO
+        syscall_assert!(unsafe { process_vm_readv(30, null(), 0, null(), 0, 0) }, 0);
+        syscall_assert!(
+            unsafe { process_vm_readv(30, null(), 40, null(), 0, 0) },
+            -222
+        );
+    }
+}

src/agent/rustjail/src/sync.rs

@@ -3,7 +3,6 @@
 // SPDX-License-Identifier: Apache-2.0
 //
 
-use nix::errno::Errno;
 use nix::unistd;
 use std::mem;
 use std::os::unix::io::RawFd;
@@ -41,7 +40,7 @@ pub fn write_count(fd: RawFd, buf: &[u8], count: usize) -> Result<usize> {
             }
 
             Err(e) => {
-                if e != nix::Error::from_errno(Errno::EINTR) {
+                if e != nix::Error::EINTR {
                     return Err(e.into());
                 }
             }
@@ -65,7 +64,7 @@ fn read_count(fd: RawFd, count: usize) -> Result<Vec<u8>> {
             }
 
             Err(e) => {
-                if e != nix::Error::from_errno(Errno::EINTR) {
+                if e != nix::Error::EINTR {
                     return Err(e.into());
                 }
             }

src/agent/rustjail/src/validator.rs

@@ -5,13 +5,12 @@
 
 use crate::container::Config;
 use anyhow::{anyhow, Context, Error, Result};
-use nix::errno::Errno;
 use oci::{Linux, LinuxIdMapping, LinuxNamespace, Spec};
 use std::collections::HashMap;
 use std::path::{Component, PathBuf};
 
 fn einval() -> Error {
-    anyhow!(nix::Error::from_errno(Errno::EINVAL))
+    anyhow!(nix::Error::EINVAL)
 }
 
 fn get_linux(oci: &Spec) -> Result<&Linux> {

src/agent/samples/configuration-all-endpoints.toml

@@ -4,18 +4,36 @@ server_addr = 'vsock://8:2048'
 
 [endpoints]
 # All endpoints are allowed
-allowed = [ "CreateContainer", "StartContainer", "RemoveContainer",
-            "ExecProcess",  "SignalProcess", "WaitProcess",
-            "UpdateContainer", "StatsContainer", "PauseContainer", "ResumeContainer",
-            "WriteStdin", "ReadStdout", "ReadStderr", "CloseStdin", "TtyWinResize",
-            "UpdateInterface", "UpdateRoutes", "ListInterfaces", "ListRoutes", "AddARPNeighbors",
-            "StartTracing", "StopTracing", "GetMetrics",
-            "CreateSandbox", "DestroySandbox",
-            "OnlineCPUMem",
-            "ReseedRandomDev",
-            "GetGuestDetails",
-            "MemHotplugByProbe",
-            "SetGuestDateTime",
-            "CopyFile",
-            "GetOOMEvent",
-            "AddSwap"]
+allowed = [
+        "AddARPNeighborsRequest",
+        "AddSwapRequest",
+        "CloseStdinRequest",
+        "CopyFileRequest",
+        "CreateContainerRequest",
+        "CreateSandboxRequest",
+        "DestroySandboxRequest",
+        "ExecProcessRequest",
+        "GetMetricsRequest",
+        "GetOOMEventRequest",
+        "GuestDetailsRequest",
+        "ListInterfacesRequest",
+        "ListRoutesRequest",
+        "MemHotplugByProbeRequest",
+        "OnlineCPUMemRequest",
+        "PauseContainerRequest",
+        "PullImageRequest",
+        "ReadStreamRequest",
+        "RemoveContainerRequest",
+        "ReseedRandomDevRequest",
+        "ResumeContainerRequest",
+        "SetGuestDateTimeRequest",
+        "SignalProcessRequest",
+        "StartContainerRequest",
+        "StatsContainerRequest",
+        "TtyWinResizeRequest",
+        "UpdateContainerRequest",
+        "UpdateInterfaceRequest",
+        "UpdateRoutesRequest",
+        "WaitProcessRequest",
+        "WriteStreamRequest"
+]

src/agent/src/config.rs

@@ -2,7 +2,7 @@
 //
 // SPDX-License-Identifier: Apache-2.0
 //
-use crate::tracer;
+use crate::rpc;
 use anyhow::{bail, ensure, Context, Result};
 use serde::Deserialize;
 use std::collections::HashSet;
@@ -33,7 +33,7 @@ const VSOCK_PORT: u16 = 1024;
 // Environment variables used for development and testing
 const SERVER_ADDR_ENV_VAR: &str = "KATA_AGENT_SERVER_ADDR";
 const LOG_LEVEL_ENV_VAR: &str = "KATA_AGENT_LOG_LEVEL";
-const TRACE_TYPE_ENV_VAR: &str = "KATA_AGENT_TRACE_TYPE";
+const TRACING_ENV_VAR: &str = "KATA_AGENT_TRACING";
 
 const ERR_INVALID_LOG_LEVEL: &str = "invalid log level";
 const ERR_INVALID_LOG_LEVEL_PARAM: &str = "invalid log level parameter";
@@ -73,8 +73,9 @@ pub struct AgentConfig {
     pub container_pipe_size: i32,
     pub server_addr: String,
     pub unified_cgroup_hierarchy: bool,
-    pub tracing: tracer::TraceType,
+    pub tracing: bool,
     pub endpoints: AgentEndpoints,
+    pub supports_seccomp: bool,
 }
 
 #[derive(Debug, Deserialize)]
@@ -88,7 +89,7 @@ pub struct AgentConfigBuilder {
     pub container_pipe_size: Option<i32>,
     pub server_addr: Option<String>,
     pub unified_cgroup_hierarchy: Option<bool>,
-    pub tracing: Option<tracer::TraceType>,
+    pub tracing: Option<bool>,
     pub endpoints: Option<EndpointsConfig>,
 }
 
@@ -148,8 +149,9 @@ impl Default for AgentConfig {
             container_pipe_size: DEFAULT_CONTAINER_PIPE_SIZE,
             server_addr: format!("{}:{}", VSOCK_ADDR, VSOCK_PORT),
             unified_cgroup_hierarchy: false,
-            tracing: tracer::TraceType::Disabled,
+            tracing: false,
             endpoints: Default::default(),
+            supports_seccomp: rpc::have_seccomp(),
         }
     }
 }
@@ -192,7 +194,17 @@ impl FromStr for AgentConfig {
 
 impl AgentConfig {
     #[instrument]
-    pub fn from_cmdline(file: &str) -> Result<AgentConfig> {
+    pub fn from_cmdline(file: &str, args: Vec<String>) -> Result<AgentConfig> {
+        // If config file specified in the args, generate our config from it
+        let config_position = args.iter().position(|a| a == "--config" || a == "-c");
+        if let Some(config_position) = config_position {
+            if let Some(config_file) = args.get(config_position + 1) {
+                return AgentConfig::from_config_file(config_file);
+            } else {
+                panic!("The config argument wasn't formed properly: {:?}", args);
+            }
+        }
+
         let mut config: AgentConfig = Default::default();
         let cmdline = fs::read_to_string(file)?;
         let params: Vec<&str> = cmdline.split_ascii_whitespace().collect();
@@ -213,11 +225,11 @@ impl AgentConfig {
             // Support "bare" tracing option for backwards compatibility with
             // Kata 1.x.
             if param == &TRACE_MODE_OPTION {
-                config.tracing = tracer::TraceType::Isolated;
+                config.tracing = true;
                 continue;
             }
 
-            parse_cmdline_param!(param, TRACE_MODE_OPTION, config.tracing, get_trace_type);
+            parse_cmdline_param!(param, TRACE_MODE_OPTION, config.tracing, get_bool_value);
 
             // parse cmdline options
             parse_cmdline_param!(param, LOG_LEVEL_OPTION, config.log_level, get_log_level);
@@ -277,10 +289,10 @@ impl AgentConfig {
             }
         }
 
-        if let Ok(value) = env::var(TRACE_TYPE_ENV_VAR) {
-            if let Ok(result) = value.parse::<tracer::TraceType>() {
-                config.tracing = result;
-            }
+        if let Ok(value) = env::var(TRACING_ENV_VAR) {
+            let name_value = format!("{}={}", TRACING_ENV_VAR, value);
+
+            config.tracing = get_bool_value(&name_value)?;
         }
 
         // We did not get a configuration file: allow all endpoints.
@@ -343,25 +355,6 @@ fn get_log_level(param: &str) -> Result<slog::Level> {
     logrus_to_slog_level(fields[1])
 }
 
-#[instrument]
-fn get_trace_type(param: &str) -> Result<tracer::TraceType> {
-    ensure!(!param.is_empty(), "invalid trace type parameter");
-
-    let fields: Vec<&str> = param.split('=').collect();
-    ensure!(
-        fields[0] == TRACE_MODE_OPTION,
-        "invalid trace type key name"
-    );
-
-    if fields.len() == 1 {
-        return Ok(tracer::TraceType::Isolated);
-    }
-
-    let result = fields[1].parse::<tracer::TraceType>()?;
-
-    Ok(result)
-}
-
 #[instrument]
 fn get_hotplug_timeout(param: &str) -> Result<time::Duration> {
     let fields: Vec<&str> = param.split('=').collect();
@@ -446,10 +439,6 @@ mod tests {
     use std::time;
     use tempfile::tempdir;
 
-    const ERR_INVALID_TRACE_TYPE_PARAM: &str = "invalid trace type parameter";
-    const ERR_INVALID_TRACE_TYPE: &str = "invalid trace type";
-    const ERR_INVALID_TRACE_TYPE_KEY: &str = "invalid trace type key name";
-
     // Parameters:
     //
     // 1: expected Result
@@ -500,7 +489,7 @@ mod tests {
             container_pipe_size: i32,
             server_addr: &'a str,
             unified_cgroup_hierarchy: bool,
-            tracing: tracer::TraceType,
+            tracing: bool,
         }
 
         impl Default for TestData<'_> {
@@ -515,7 +504,7 @@ mod tests {
                     container_pipe_size: DEFAULT_CONTAINER_PIPE_SIZE,
                     server_addr: TEST_SERVER_ADDR,
                     unified_cgroup_hierarchy: false,
-                    tracing: tracer::TraceType::Disabled,
+                    tracing: false,
                 }
             }
         }
@@ -774,49 +763,115 @@ mod tests {
             },
             TestData {
                 contents: "trace",
-                tracing: tracer::TraceType::Disabled,
+                tracing: false,
                 ..Default::default()
             },
             TestData {
                 contents: ".trace",
-                tracing: tracer::TraceType::Disabled,
+                tracing: false,
                 ..Default::default()
             },
             TestData {
                 contents: "agent.tracer",
-                tracing: tracer::TraceType::Disabled,
+                tracing: false,
                 ..Default::default()
             },
             TestData {
                 contents: "agent.trac",
-                tracing: tracer::TraceType::Disabled,
+                tracing: false,
                 ..Default::default()
             },
             TestData {
                 contents: "agent.trace",
-                tracing: tracer::TraceType::Isolated,
+                tracing: true,
                 ..Default::default()
             },
             TestData {
-                contents: "agent.trace=isolated",
-                tracing: tracer::TraceType::Isolated,
+                contents: "agent.trace=true",
+                tracing: true,
                 ..Default::default()
             },
             TestData {
-                contents: "agent.trace=disabled",
-                tracing: tracer::TraceType::Disabled,
+                contents: "agent.trace=false",
+                tracing: false,
+                ..Default::default()
+            },
+            TestData {
+                contents: "agent.trace=0",
+                tracing: false,
+                ..Default::default()
+            },
+            TestData {
+                contents: "agent.trace=1",
+                tracing: true,
+                ..Default::default()
+            },
+            TestData {
+                contents: "agent.trace=a",
+                tracing: false,
+                ..Default::default()
+            },
+            TestData {
+                contents: "agent.trace=foo",
+                tracing: false,
+                ..Default::default()
+            },
+            TestData {
+                contents: "agent.trace=.",
+                tracing: false,
+                ..Default::default()
+            },
+            TestData {
+                contents: "agent.trace=,",
+                tracing: false,
                 ..Default::default()
             },
             TestData {
                 contents: "",
-                env_vars: vec!["KATA_AGENT_TRACE_TYPE=isolated"],
-                tracing: tracer::TraceType::Isolated,
+                env_vars: vec!["KATA_AGENT_TRACING="],
+                tracing: false,
                 ..Default::default()
             },
             TestData {
                 contents: "",
-                env_vars: vec!["KATA_AGENT_TRACE_TYPE=disabled"],
-                tracing: tracer::TraceType::Disabled,
+                env_vars: vec!["KATA_AGENT_TRACING=''"],
+                tracing: false,
+                ..Default::default()
+            },
+            TestData {
+                contents: "",
+                env_vars: vec!["KATA_AGENT_TRACING=0"],
+                tracing: false,
+                ..Default::default()
+            },
+            TestData {
+                contents: "",
+                env_vars: vec!["KATA_AGENT_TRACING=."],
+                tracing: false,
+                ..Default::default()
+            },
+            TestData {
+                contents: "",
+                env_vars: vec!["KATA_AGENT_TRACING=,"],
+                tracing: false,
+                ..Default::default()
+            },
+            TestData {
+                contents: "",
+                env_vars: vec!["KATA_AGENT_TRACING=foo"],
+                tracing: false,
+                ..Default::default()
+            },
+            TestData {
+                contents: "",
+                env_vars: vec!["KATA_AGENT_TRACING=1"],
+                tracing: true,
+                ..Default::default()
+            },
+            TestData {
+                contents: "",
+                env_vars: vec!["KATA_AGENT_TRACING=true"],
+                tracing: true,
                 ..Default::default()
             },
         ];
@@ -851,7 +906,8 @@ mod tests {
                 vars_to_unset.push(name);
             }
 
-            let config = AgentConfig::from_cmdline(filename).expect("Failed to parse command line");
+            let config =
+                AgentConfig::from_cmdline(filename, vec![]).expect("Failed to parse command line");
 
             assert_eq!(d.debug_console, config.debug_console, "{}", msg);
             assert_eq!(d.dev_mode, config.dev_mode, "{}", msg);
@@ -872,6 +928,40 @@ mod tests {
         }
     }
 
+    #[test]
+    fn test_from_cmdline_with_args_overwrites() {
+        let expected = AgentConfig {
+            dev_mode: true,
+            server_addr: "unix://@/tmp/foo.socket".to_string(),
+            ..Default::default()
+        };
+
+        let example_config_file_contents =
+            "dev_mode = true\nserver_addr = 'unix://@/tmp/foo.socket'";
+        let dir = tempdir().expect("failed to create tmpdir");
+        let file_path = dir.path().join("config.toml");
+        let filename = file_path.to_str().expect("failed to create filename");
+        let mut file = File::create(filename).unwrap_or_else(|_| panic!("failed to create file"));
+        file.write_all(example_config_file_contents.as_bytes())
+            .unwrap_or_else(|_| panic!("failed to write file contents"));
+
+        let config =
+            AgentConfig::from_cmdline("", vec!["--config".to_string(), filename.to_string()])
+                .expect("Failed to parse command line");
+
+        assert_eq!(expected.debug_console, config.debug_console);
+        assert_eq!(expected.dev_mode, config.dev_mode);
+        assert_eq!(
+            expected.unified_cgroup_hierarchy,
+            config.unified_cgroup_hierarchy,
+        );
+        assert_eq!(expected.log_level, config.log_level);
+        assert_eq!(expected.hotplug_timeout, config.hotplug_timeout);
+        assert_eq!(expected.container_pipe_size, config.container_pipe_size);
+        assert_eq!(expected.server_addr, config.server_addr);
+        assert_eq!(expected.tracing, config.tracing);
+    }
+
     #[test]
     fn test_logrus_to_slog_level() {
         #[derive(Debug)]
@@ -1302,64 +1392,6 @@ Caused by:
         }
     }
 
-    #[test]
-    fn test_get_trace_type() {
-        #[derive(Debug)]
-        struct TestData<'a> {
-            param: &'a str,
-            result: Result<tracer::TraceType>,
-        }
-
-        let tests = &[
-            TestData {
-                param: "",
-                result: Err(anyhow!(ERR_INVALID_TRACE_TYPE_PARAM)),
-            },
-            TestData {
-                param: "agent.tracer",
-                result: Err(anyhow!(ERR_INVALID_TRACE_TYPE_KEY)),
-            },
-            TestData {
-                param: "agent.trac",
-                result: Err(anyhow!(ERR_INVALID_TRACE_TYPE_KEY)),
-            },
-            TestData {
-                param: "agent.trace=",
-                result: Err(anyhow!(ERR_INVALID_TRACE_TYPE)),
-            },
-            TestData {
-                param: "agent.trace==",
-                result: Err(anyhow!(ERR_INVALID_TRACE_TYPE)),
-            },
-            TestData {
-                param: "agent.trace=foo",
-                result: Err(anyhow!(ERR_INVALID_TRACE_TYPE)),
-            },
-            TestData {
-                param: "agent.trace",
-                result: Ok(tracer::TraceType::Isolated),
-            },
-            TestData {
-                param: "agent.trace=isolated",
-                result: Ok(tracer::TraceType::Isolated),
-            },
-            TestData {
-                param: "agent.trace=disabled",
-                result: Ok(tracer::TraceType::Disabled),
-            },
-        ];
-
-        for (i, d) in tests.iter().enumerate() {
-            let msg = format!("test[{}]: {:?}", i, d);
-
-            let result = get_trace_type(d.param);
-
-            let msg = format!("{}: result: {:?}", msg, result);
-
-            assert_result!(d.result, result, msg);
-        }
-    }
-
     #[test]
     fn test_config_builder_from_string() {
         let config = AgentConfig::from_str(

src/agent/src/console.rs

@@ -149,10 +149,8 @@ fn run_in_child(slave_fd: libc::c_int, shell: String) -> Result<()> {
 
     // run shell
     let _ = unistd::execvp(cmd.as_c_str(), &args).map_err(|e| match e {
-        nix::Error::Sys(errno) => {
-            std::process::exit(errno as i32);
-        }
-        _ => std::process::exit(-2),
+        nix::Error::UnknownErrno => std::process::exit(-2),
+        _ => std::process::exit(e as i32),
     });
 
     Ok(())

src/agent/src/linux_abi.rs

@@ -83,6 +83,8 @@ pub const SYSFS_MEMORY_ONLINE_PATH: &str = "/sys/devices/system/memory";
 
 pub const SYSFS_SCSI_HOST_PATH: &str = "/sys/class/scsi_host";
 
+pub const SYSFS_BUS_PCI_PATH: &str = "/sys/bus/pci";
+
 pub const SYSFS_CGROUPPATH: &str = "/sys/fs/cgroup";
 pub const SYSFS_ONLINE_FILE: &str = "online";
 
@@ -94,6 +96,7 @@ pub const SYSTEM_DEV_PATH: &str = "/dev";
 // Linux UEvent related consts.
 pub const U_EVENT_ACTION: &str = "ACTION";
 pub const U_EVENT_ACTION_ADD: &str = "add";
+pub const U_EVENT_ACTION_REMOVE: &str = "remove";
 pub const U_EVENT_DEV_PATH: &str = "DEVPATH";
 pub const U_EVENT_SUB_SYSTEM: &str = "SUBSYSTEM";
 pub const U_EVENT_SEQ_NUM: &str = "SEQNUM";

src/agent/src/main.rs

@@ -20,6 +20,7 @@ extern crate scopeguard;
 extern crate slog;
 
 use anyhow::{anyhow, Context, Result};
+use clap::{AppSettings, Parser};
 use nix::fcntl::OFlag;
 use nix::sys::socket::{self, AddressFamily, SockAddr, SockFlag, SockType};
 use nix::unistd::{self, dup, Pid};
@@ -80,10 +81,32 @@ const NAME: &str = "kata-agent";
 
 lazy_static! {
     static ref AGENT_CONFIG: Arc<RwLock<AgentConfig>> = Arc::new(RwLock::new(
-        AgentConfig::from_cmdline("/proc/cmdline").unwrap()
+        // Note: We can't do AgentOpts.parse() here to send through the processed arguments to AgentConfig
+        // clap::Parser::parse() greedily process all command line input including cargo test parameters,
+        // so should only be used inside main.
+        AgentConfig::from_cmdline("/proc/cmdline", env::args().collect()).unwrap()
     ));
 }
 
+#[derive(Parser)]
+// The default clap version info doesn't match our form, so we need to override it
+#[clap(global_setting(AppSettings::DisableVersionFlag))]
+struct AgentOpts {
+    /// Print the version information
+    #[clap(short, long)]
+    version: bool,
+    #[clap(subcommand)]
+    subcmd: Option<SubCommand>,
+    /// Specify a custom agent config file
+    #[clap(short, long)]
+    config: Option<String>,
+}
+
+#[derive(Parser)]
+enum SubCommand {
+    Init {},
+}
+
 #[instrument]
 fn announce(logger: &Logger, config: &AgentConfig) {
     info!(logger, "announce";
@@ -113,10 +136,10 @@ async fn create_logger_task(rfd: RawFd, vsock_port: u32, shutdown: Receiver<bool
         )?;
 
         let addr = SockAddr::new_vsock(libc::VMADDR_CID_ANY, vsock_port);
-        socket::bind(listenfd, &addr).unwrap();
-        socket::listen(listenfd, 1).unwrap();
+        socket::bind(listenfd, &addr)?;
+        socket::listen(listenfd, 1)?;
 
-        writer = Box::new(util::get_vsock_stream(listenfd).await.unwrap());
+        writer = Box::new(util::get_vsock_stream(listenfd).await?);
     } else {
         writer = Box::new(tokio::io::stdout());
     }
@@ -196,8 +219,8 @@ async fn real_main() -> std::result::Result<(), Box<dyn std::error::Error>> {
         ttrpc_log_guard = Ok(slog_stdlog::init().map_err(|e| e)?);
     }
 
-    if config.tracing != tracer::TraceType::Disabled {
-        let _ = tracer::setup_tracing(NAME, &logger, &config)?;
+    if config.tracing {
+        tracer::setup_tracing(NAME, &logger)?;
     }
 
     let root_span = span!(tracing::Level::TRACE, "root-span");
@@ -229,29 +252,35 @@ async fn real_main() -> std::result::Result<(), Box<dyn std::error::Error>> {
     // Wait for all threads to finish
     let results = join_all(tasks).await;
 
-    for result in results {
-        if let Err(e) = result {
-            return Err(anyhow!(e).into());
-        }
-    }
-
     // force flushing spans
     drop(span_guard);
     drop(root_span);
 
-    if config.tracing != tracer::TraceType::Disabled {
+    if config.tracing {
         tracer::end_tracing();
     }
 
     eprintln!("{} shutdown complete", NAME);
 
-    Ok(())
+    let mut wait_errors: Vec<tokio::task::JoinError> = vec![];
+    for result in results {
+        if let Err(e) = result {
+            eprintln!("wait task error: {:#?}", e);
+            wait_errors.push(e);
+        }
+    }
+
+    if wait_errors.is_empty() {
+        Ok(())
+    } else {
+        Err(anyhow!("wait all tasks failed: {:#?}", wait_errors).into())
+    }
 }
 
 fn main() -> std::result::Result<(), Box<dyn std::error::Error>> {
-    let args: Vec<String> = env::args().collect();
+    let args = AgentOpts::parse();
 
-    if args.len() == 2 && args[1] == "--version" {
+    if args.version {
         println!(
             "{} version {} (api version: {}, commit version: {}, type: rust)",
             NAME,
@@ -259,11 +288,10 @@ fn main() -> std::result::Result<(), Box<dyn std::error::Error>> {
             version::API_VERSION,
             version::VERSION_COMMIT,
         );
-
         exit(0);
     }
 
-    if args.len() == 2 && args[1] == "init" {
+    if let Some(SubCommand::Init {}) = args.subcmd {
         reset_sigpipe();
         rustjail::container::init_child();
         exit(0);
@@ -320,7 +348,7 @@ async fn start_sandbox(
     sandbox.lock().await.sender = Some(tx);
 
     // vsock:///dev/vsock, port
-    let mut server = rpc::start(sandbox.clone(), config.server_addr.as_str());
+    let mut server = rpc::start(sandbox.clone(), config.server_addr.as_str())?;
     server.start().await?;
 
     rx.await?;

src/agent/src/metrics.rs

@@ -8,6 +8,7 @@ extern crate procfs;
 use prometheus::{Encoder, Gauge, GaugeVec, IntCounter, TextEncoder};
 
 use anyhow::Result;
+use slog::warn;
 use tracing::instrument;
 
 const NAMESPACE_KATA_AGENT: &str = "kata_agent";
@@ -23,50 +24,50 @@ macro_rules! sl {
 lazy_static! {
 
     static ref     AGENT_SCRAPE_COUNT: IntCounter =
-    prometheus::register_int_counter!(format!("{}_{}",NAMESPACE_KATA_AGENT,"scrape_count").as_ref(), "Metrics scrape count").unwrap();
+    prometheus::register_int_counter!(format!("{}_{}",NAMESPACE_KATA_AGENT,"scrape_count"), "Metrics scrape count").unwrap();
 
     static ref     AGENT_THREADS: Gauge =
-    prometheus::register_gauge!(format!("{}_{}",NAMESPACE_KATA_AGENT,"threads").as_ref(), "Agent process threads").unwrap();
+    prometheus::register_gauge!(format!("{}_{}",NAMESPACE_KATA_AGENT,"threads"), "Agent process threads").unwrap();
 
     static ref     AGENT_TOTAL_TIME: Gauge =
-    prometheus::register_gauge!(format!("{}_{}",NAMESPACE_KATA_AGENT,"total_time").as_ref(), "Agent process total time").unwrap();
+    prometheus::register_gauge!(format!("{}_{}",NAMESPACE_KATA_AGENT,"total_time"), "Agent process total time").unwrap();
 
     static ref     AGENT_TOTAL_VM: Gauge =
-    prometheus::register_gauge!(format!("{}_{}",NAMESPACE_KATA_AGENT,"total_vm").as_ref(), "Agent process total VM size").unwrap();
+    prometheus::register_gauge!(format!("{}_{}",NAMESPACE_KATA_AGENT,"total_vm"), "Agent process total VM size").unwrap();
 
     static ref     AGENT_TOTAL_RSS: Gauge =
-    prometheus::register_gauge!(format!("{}_{}",NAMESPACE_KATA_AGENT,"total_rss").as_ref(), "Agent process total RSS size").unwrap();
+    prometheus::register_gauge!(format!("{}_{}",NAMESPACE_KATA_AGENT,"total_rss"), "Agent process total RSS size").unwrap();
 
     static ref     AGENT_PROC_STATUS: GaugeVec =
-    prometheus::register_gauge_vec!(format!("{}_{}",NAMESPACE_KATA_AGENT,"proc_status").as_ref(), "Agent process status.", &["item"]).unwrap();
+    prometheus::register_gauge_vec!(format!("{}_{}",NAMESPACE_KATA_AGENT,"proc_status"), "Agent process status.", &["item"]).unwrap();
 
     static ref     AGENT_IO_STAT: GaugeVec =
-    prometheus::register_gauge_vec!(format!("{}_{}",NAMESPACE_KATA_AGENT,"io_stat").as_ref(), "Agent process IO statistics.", &["item"]).unwrap();
+    prometheus::register_gauge_vec!(format!("{}_{}",NAMESPACE_KATA_AGENT,"io_stat"), "Agent process IO statistics.", &["item"]).unwrap();
 
     static ref     AGENT_PROC_STAT: GaugeVec =
-    prometheus::register_gauge_vec!(format!("{}_{}",NAMESPACE_KATA_AGENT,"proc_stat").as_ref(), "Agent process statistics.", &["item"]).unwrap();
+    prometheus::register_gauge_vec!(format!("{}_{}",NAMESPACE_KATA_AGENT,"proc_stat"), "Agent process statistics.", &["item"]).unwrap();
 
     // guest os metrics
     static ref     GUEST_LOAD: GaugeVec =
-    prometheus::register_gauge_vec!(format!("{}_{}",NAMESPACE_KATA_GUEST,"load").as_ref() , "Guest system load.", &["item"]).unwrap();
+    prometheus::register_gauge_vec!(format!("{}_{}",NAMESPACE_KATA_GUEST,"load") , "Guest system load.", &["item"]).unwrap();
 
     static ref     GUEST_TASKS: GaugeVec =
-    prometheus::register_gauge_vec!(format!("{}_{}",NAMESPACE_KATA_GUEST,"tasks").as_ref() , "Guest system load.", &["item"]).unwrap();
+    prometheus::register_gauge_vec!(format!("{}_{}",NAMESPACE_KATA_GUEST,"tasks") , "Guest system load.", &["item"]).unwrap();
 
     static ref     GUEST_CPU_TIME: GaugeVec =
-    prometheus::register_gauge_vec!(format!("{}_{}",NAMESPACE_KATA_GUEST,"cpu_time").as_ref() , "Guest CPU statistics.", &["cpu","item"]).unwrap();
+    prometheus::register_gauge_vec!(format!("{}_{}",NAMESPACE_KATA_GUEST,"cpu_time") , "Guest CPU statistics.", &["cpu","item"]).unwrap();
 
     static ref     GUEST_VM_STAT: GaugeVec =
-    prometheus::register_gauge_vec!(format!("{}_{}",NAMESPACE_KATA_GUEST,"vm_stat").as_ref() , "Guest virtual memory statistics.", &["item"]).unwrap();
+    prometheus::register_gauge_vec!(format!("{}_{}",NAMESPACE_KATA_GUEST,"vm_stat") , "Guest virtual memory statistics.", &["item"]).unwrap();
 
     static ref     GUEST_NETDEV_STAT: GaugeVec =
-    prometheus::register_gauge_vec!(format!("{}_{}",NAMESPACE_KATA_GUEST,"netdev_stat").as_ref() , "Guest net devices statistics.", &["interface","item"]).unwrap();
+    prometheus::register_gauge_vec!(format!("{}_{}",NAMESPACE_KATA_GUEST,"netdev_stat") , "Guest net devices statistics.", &["interface","item"]).unwrap();
 
     static ref     GUEST_DISKSTAT: GaugeVec =
-    prometheus::register_gauge_vec!(format!("{}_{}",NAMESPACE_KATA_GUEST,"diskstat").as_ref() , "Disks statistics in system.", &["disk","item"]).unwrap();
+    prometheus::register_gauge_vec!(format!("{}_{}",NAMESPACE_KATA_GUEST,"diskstat") , "Disks statistics in system.", &["disk","item"]).unwrap();
 
     static ref     GUEST_MEMINFO: GaugeVec =
-    prometheus::register_gauge_vec!(format!("{}_{}",NAMESPACE_KATA_GUEST,"meminfo").as_ref() , "Statistics about memory usage in the system.", &["item"]).unwrap();
+    prometheus::register_gauge_vec!(format!("{}_{}",NAMESPACE_KATA_GUEST,"meminfo") , "Statistics about memory usage in the system.", &["item"]).unwrap();
 }
 
 #[instrument]
@@ -74,7 +75,7 @@ pub fn get_metrics(_: &protocols::agent::GetMetricsRequest) -> Result<String> {
     AGENT_SCRAPE_COUNT.inc();
 
     // update agent process metrics
-    update_agent_metrics();
+    update_agent_metrics()?;
 
     // update guest os metrics
     update_guest_metrics();
@@ -84,23 +85,26 @@ pub fn get_metrics(_: &protocols::agent::GetMetricsRequest) -> Result<String> {
 
     let mut buffer = Vec::new();
     let encoder = TextEncoder::new();
-    encoder.encode(&metric_families, &mut buffer).unwrap();
+    encoder.encode(&metric_families, &mut buffer)?;
 
-    Ok(String::from_utf8(buffer).unwrap())
+    Ok(String::from_utf8(buffer)?)
 }
 
 #[instrument]
-fn update_agent_metrics() {
+fn update_agent_metrics() -> Result<()> {
     let me = procfs::process::Process::myself();
 
-    if let Err(err) = me {
-        error!(sl!(), "failed to create process instance: {:?}", err);
-        return;
-    }
+    let me = match me {
+        Ok(p) => p,
+        Err(e) => {
+            // FIXME: return Ok for all errors?
+            warn!(sl!(), "failed to create process instance: {:?}", e);
 
-    let me = me.unwrap();
+            return Ok(());
+        }
+    };
 
-    let tps = procfs::ticks_per_second().unwrap();
+    let tps = procfs::ticks_per_second()?;
 
     // process total time
     AGENT_TOTAL_TIME.set((me.stat.utime + me.stat.stime) as f64 / (tps as f64));
@@ -109,7 +113,7 @@ fn update_agent_metrics() {
     AGENT_TOTAL_VM.set(me.stat.vsize as f64);
 
     // Total resident set
-    let page_size = procfs::page_size().unwrap() as f64;
+    let page_size = procfs::page_size()? as f64;
     AGENT_TOTAL_RSS.set(me.stat.rss as f64 * page_size);
 
     // io
@@ -132,11 +136,11 @@ fn update_agent_metrics() {
     }
 
     match me.status() {
-        Err(err) => {
-            info!(sl!(), "failed to get process status: {:?}", err);
-        }
+        Err(err) => error!(sl!(), "failed to get process status: {:?}", err),
         Ok(status) => set_gauge_vec_proc_status(&AGENT_PROC_STATUS, &status),
     }
+
+    Ok(())
 }
 
 #[instrument]
@@ -348,17 +352,17 @@ fn set_gauge_vec_cpu_time(gv: &prometheus::GaugeVec, cpu: &str, cpu_time: &procf
     gv.with_label_values(&[cpu, "idle"])
         .set(cpu_time.idle as f64);
     gv.with_label_values(&[cpu, "iowait"])
-        .set(cpu_time.iowait.unwrap_or(0.0) as f64);
+        .set(cpu_time.iowait.unwrap_or(0) as f64);
     gv.with_label_values(&[cpu, "irq"])
-        .set(cpu_time.irq.unwrap_or(0.0) as f64);
+        .set(cpu_time.irq.unwrap_or(0) as f64);
     gv.with_label_values(&[cpu, "softirq"])
-        .set(cpu_time.softirq.unwrap_or(0.0) as f64);
+        .set(cpu_time.softirq.unwrap_or(0) as f64);
     gv.with_label_values(&[cpu, "steal"])
-        .set(cpu_time.steal.unwrap_or(0.0) as f64);
+        .set(cpu_time.steal.unwrap_or(0) as f64);
     gv.with_label_values(&[cpu, "guest"])
-        .set(cpu_time.guest.unwrap_or(0.0) as f64);
+        .set(cpu_time.guest.unwrap_or(0) as f64);
     gv.with_label_values(&[cpu, "guest_nice"])
-        .set(cpu_time.guest_nice.unwrap_or(0.0) as f64);
+        .set(cpu_time.guest_nice.unwrap_or(0) as f64);
 }
 
 #[instrument]
@@ -470,7 +474,7 @@ fn set_gauge_vec_proc_status(gv: &prometheus::GaugeVec, status: &procfs::process
     gv.with_label_values(&["vmswap"])
         .set(status.vmswap.unwrap_or(0) as f64);
     gv.with_label_values(&["hugetlbpages"])
-        .set(status.hugetblpages.unwrap_or(0) as f64);
+        .set(status.hugetlbpages.unwrap_or(0) as f64);
     gv.with_label_values(&["voluntary_ctxt_switches"])
         .set(status.voluntary_ctxt_switches.unwrap_or(0) as f64);
     gv.with_label_values(&["nonvoluntary_ctxt_switches"])

src/agent/src/mount.rs

@@ -139,8 +139,8 @@ pub const STORAGE_HANDLER_LIST: &[&str] = &[
 
 #[instrument]
 pub fn baremount(
-    source: &str,
-    destination: &str,
+    source: &Path,
+    destination: &Path,
     fs_type: &str,
     flags: MsFlags,
     options: &str,
@@ -148,11 +148,11 @@ pub fn baremount(
 ) -> Result<()> {
     let logger = logger.new(o!("subsystem" => "baremount"));
 
-    if source.is_empty() {
+    if source.as_os_str().is_empty() {
         return Err(anyhow!("need mount source"));
     }
 
-    if destination.is_empty() {
+    if destination.as_os_str().is_empty() {
         return Err(anyhow!("need mount destination"));
     }
 
@@ -405,14 +405,18 @@ async fn bind_watcher_storage_handler(
     logger: &Logger,
     storage: &Storage,
     sandbox: Arc<Mutex<Sandbox>>,
+    cid: Option<String>,
 ) -> Result<()> {
     let mut locked = sandbox.lock().await;
-    let container_id = locked.id.clone();
 
-    locked
-        .bind_watcher
-        .add_container(container_id, iter::once(storage.clone()), logger)
-        .await
+    if let Some(cid) = cid {
+        locked
+            .bind_watcher
+            .add_container(cid, iter::once(storage.clone()), logger)
+            .await
+    } else {
+        Ok(())
+    }
 }
 
 // mount_storage performs the mount described by the storage structure.
@@ -444,16 +448,18 @@ fn mount_storage(logger: &Logger, storage: &Storage) -> Result<()> {
     let options_vec = options_vec.iter().map(String::as_str).collect();
     let (flags, options) = parse_mount_flags_and_options(options_vec);
 
+    let source = Path::new(&storage.source);
+
     info!(logger, "mounting storage";
-    "mount-source:" => storage.source.as_str(),
-    "mount-destination" => storage.mount_point.as_str(),
+    "mount-source" => source.display(),
+    "mount-destination" => mount_path.display(),
     "mount-fstype"  => storage.fstype.as_str(),
     "mount-options" => options.as_str(),
     );
 
     baremount(
-        storage.source.as_str(),
-        storage.mount_point.as_str(),
+        source,
+        mount_path,
         storage.fstype.as_str(),
         flags,
         options.as_str(),
@@ -518,6 +524,7 @@ pub async fn add_storages(
     logger: Logger,
     storages: Vec<Storage>,
     sandbox: Arc<Mutex<Sandbox>>,
+    cid: Option<String>,
 ) -> Result<Vec<String>> {
     let mut mount_list = Vec::new();
 
@@ -548,7 +555,8 @@ pub async fn add_storages(
             }
             DRIVER_NVDIMM_TYPE => nvdimm_storage_handler(&logger, &storage, sandbox.clone()).await,
             DRIVER_WATCHABLE_BIND_TYPE => {
-                bind_watcher_storage_handler(&logger, &storage, sandbox.clone()).await?;
+                bind_watcher_storage_handler(&logger, &storage, sandbox.clone(), cid.clone())
+                    .await?;
                 // Don't register watch mounts, they're handled separately by the watcher.
                 Ok(String::new())
             }
@@ -579,7 +587,10 @@ fn mount_to_rootfs(logger: &Logger, m: &InitMount) -> Result<()> {
 
     fs::create_dir_all(Path::new(m.dest)).context("could not create directory")?;
 
-    baremount(m.src, m.dest, m.fstype, flags, &options, logger).or_else(|e| {
+    let source = Path::new(m.src);
+    let dest = Path::new(m.dest);
+
+    baremount(source, dest, m.fstype, flags, &options, logger).or_else(|e| {
         if m.src != "dev" {
             return Err(e);
         }
@@ -622,8 +633,7 @@ pub fn get_mount_fs_type_from_file(mount_file: &str, mount_point: &str) -> Resul
     let file = File::open(mount_file)?;
     let reader = BufReader::new(file);
 
-    let re = Regex::new(format!("device .+ mounted on {} with fstype (.+)", mount_point).as_str())
-        .unwrap();
+    let re = Regex::new(format!("device .+ mounted on {} with fstype (.+)", mount_point).as_str())?;
 
     // Read the file line by line using the lines() iterator from std::io::BufRead.
     for (_index, line) in reader.lines().enumerate() {
@@ -701,20 +711,21 @@ pub fn get_cgroup_mounts(
             }
         }
 
-        if fields[0].is_empty() {
+        let subsystem_name = fields[0];
+
+        if subsystem_name.is_empty() {
             continue;
         }
 
-        if fields[0] == "devices" {
+        if subsystem_name == "devices" {
             has_device_cgroup = true;
         }
 
-        if let Some(value) = CGROUPS.get(&fields[0]) {
-            let key = CGROUPS.keys().find(|&&f| f == fields[0]).unwrap();
+        if let Some((key, value)) = CGROUPS.get_key_value(subsystem_name) {
             cg_mounts.push(InitMount {
                 fstype: "cgroup",
                 src: "cgroup",
-                dest: *value,
+                dest: value,
                 options: vec!["nosuid", "nodev", "noexec", "relatime", key],
             });
         }
@@ -767,10 +778,9 @@ fn ensure_destination_file_exists(path: &Path) -> Result<()> {
         return Err(anyhow!("{:?} exists but is not a regular file", path));
     }
 
-    // The only way parent() can return None is if the path is /,
-    // which always exists, so the test above will already have caught
-    // it, thus the unwrap() is safe
-    let dir = path.parent().unwrap();
+    let dir = path
+        .parent()
+        .ok_or_else(|| anyhow!("failed to find parent path for {:?}", path))?;
 
     fs::create_dir_all(dir).context(format!("create_dir_all {:?}", dir))?;
 
@@ -937,14 +947,10 @@ mod tests {
                 std::fs::create_dir_all(d).expect("failed to created directory");
             }
 
-            let result = baremount(
-                &src_filename,
-                &dest_filename,
-                d.fs_type,
-                d.flags,
-                d.options,
-                &logger,
-            );
+            let src = Path::new(&src_filename);
+            let dest = Path::new(&dest_filename);
+
+            let result = baremount(src, dest, d.fs_type, d.flags, d.options, &logger);
 
             let msg = format!("{}: result: {:?}", msg, result);
 
@@ -1021,15 +1027,11 @@ mod tests {
                 .unwrap_or_else(|_| panic!("failed to create directory {}", d));
         }
 
+        let src = Path::new(mnt_src_filename);
+        let dest = Path::new(mnt_dest_filename);
+
         // Create an actual mount
-        let result = baremount(
-            mnt_src_filename,
-            mnt_dest_filename,
-            "bind",
-            MsFlags::MS_BIND,
-            "",
-            &logger,
-        );
+        let result = baremount(src, dest, "bind", MsFlags::MS_BIND, "", &logger);
         assert!(result.is_ok(), "mount for test setup failed");
 
         let tests = &[

src/agent/src/namespace.rs

@@ -104,7 +104,10 @@ impl Namespace {
             if let Err(err) = || -> Result<()> {
                 let origin_ns_path = get_current_thread_ns_path(ns_type.get());
 
-                File::open(Path::new(&origin_ns_path))?;
+                let source = Path::new(&origin_ns_path);
+                let destination = new_ns_path.as_path();
+
+                File::open(&source)?;
 
                 // Create a new netns on the current thread.
                 let cf = ns_type.get_flags();
@@ -115,8 +118,6 @@ impl Namespace {
                     nix::unistd::sethostname(hostname.unwrap())?;
                 }
                 // Bind mount the new namespace from the current thread onto the mount point to persist it.
-                let source: &str = origin_ns_path.as_str();
-                let destination: &str = new_ns_path.as_path().to_str().unwrap_or("none");
 
                 let mut flags = MsFlags::empty();
 
@@ -131,7 +132,7 @@ impl Namespace {
 
                 baremount(source, destination, "none", flags, "", &logger).map_err(|e| {
                     anyhow!(
-                        "Failed to mount {} to {} with err:{:?}",
+                        "Failed to mount {:?} to {:?} with err:{:?}",
                         source,
                         destination,
                         e
@@ -250,4 +251,126 @@ mod tests {
         assert_eq!("pid", pid.get());
         assert_eq!(CloneFlags::CLONE_NEWPID, pid.get_flags());
     }
+
+    #[test]
+    fn test_new() {
+        // Create dummy logger and temp folder.
+        let logger = slog::Logger::root(slog::Discard, o!());
+
+        let ns_ipc = Namespace::new(&logger);
+        assert_eq!(NamespaceType::Ipc, ns_ipc.ns_type);
+    }
+
+    #[test]
+    fn test_get_ipc() {
+        // Create dummy logger and temp folder.
+        let logger = slog::Logger::root(slog::Discard, o!());
+
+        let ns_ipc = Namespace::new(&logger).get_ipc();
+        assert_eq!(NamespaceType::Ipc, ns_ipc.ns_type);
+    }
+
+    #[test]
+    fn test_get_uts_with_hostname() {
+        let hostname = String::from("a.test.com");
+        // Create dummy logger and temp folder.
+        let logger = slog::Logger::root(slog::Discard, o!());
+
+        let ns_uts = Namespace::new(&logger).get_uts(hostname.as_str());
+        assert_eq!(NamespaceType::Uts, ns_uts.ns_type);
+        assert!(ns_uts.hostname.is_some());
+    }
+
+    #[test]
+    fn test_get_uts() {
+        let hostname = String::from("");
+        // Create dummy logger and temp folder.
+        let logger = slog::Logger::root(slog::Discard, o!());
+
+        let ns_uts = Namespace::new(&logger).get_uts(hostname.as_str());
+        assert_eq!(NamespaceType::Uts, ns_uts.ns_type);
+        assert!(ns_uts.hostname.is_none());
+    }
+
+    #[test]
+    fn test_get_pid() {
+        // Create dummy logger and temp folder.
+        let logger = slog::Logger::root(slog::Discard, o!());
+
+        let ns_pid = Namespace::new(&logger).get_pid();
+        assert_eq!(NamespaceType::Pid, ns_pid.ns_type);
+    }
+
+    #[test]
+    fn test_set_root_dir() {
+        // Create dummy logger and temp folder.
+        let logger = slog::Logger::root(slog::Discard, o!());
+        let tmpdir = Builder::new().prefix("pid").tempdir().unwrap();
+
+        let ns_root = Namespace::new(&logger).set_root_dir(tmpdir.path().to_str().unwrap());
+        assert_eq!(NamespaceType::Ipc, ns_root.ns_type);
+        assert_eq!(ns_root.persistent_ns_dir, tmpdir.path().to_str().unwrap());
+    }
+
+    #[test]
+    fn test_namespace_type_get() {
+        #[derive(Debug)]
+        struct TestData<'a> {
+            ns_type: NamespaceType,
+            str: &'a str,
+        }
+
+        let tests = &[
+            TestData {
+                ns_type: NamespaceType::Ipc,
+                str: "ipc",
+            },
+            TestData {
+                ns_type: NamespaceType::Uts,
+                str: "uts",
+            },
+            TestData {
+                ns_type: NamespaceType::Pid,
+                str: "pid",
+            },
+        ];
+
+        // Run the tests
+        for (i, d) in tests.iter().enumerate() {
+            // Create a string containing details of the test
+            let msg = format!("test[{}]: {:?}", i, d);
+            assert_eq!(d.str, d.ns_type.get(), "{}", msg)
+        }
+    }
+
+    #[test]
+    fn test_namespace_type_get_flags() {
+        #[derive(Debug)]
+        struct TestData {
+            ns_type: NamespaceType,
+            ns_flag: CloneFlags,
+        }
+
+        let tests = &[
+            TestData {
+                ns_type: NamespaceType::Ipc,
+                ns_flag: CloneFlags::CLONE_NEWIPC,
+            },
+            TestData {
+                ns_type: NamespaceType::Uts,
+                ns_flag: CloneFlags::CLONE_NEWUTS,
+            },
+            TestData {
+                ns_type: NamespaceType::Pid,
+                ns_flag: CloneFlags::CLONE_NEWPID,
+            },
+        ];
+
+        // Run the tests
+        for (i, d) in tests.iter().enumerate() {
+            // Create a string containing details of the test
+            let msg = format!("test[{}]: {:?}", i, d);
+            assert_eq!(d.ns_flag, d.ns_type.get_flags(), "{}", msg)
+        }
+    }
 }

src/agent/src/netlink.rs

@@ -6,6 +6,7 @@
 use anyhow::{anyhow, Context, Result};
 use futures::{future, StreamExt, TryStreamExt};
 use ipnetwork::{IpNetwork, Ipv4Network, Ipv6Network};
+use nix::errno::Errno;
 use protobuf::RepeatedField;
 use protocols::types::{ARPNeighbor, IPAddress, IPFamily, Interface, Route};
 use rtnetlink::{new_connection, packet, IpVersion};
@@ -363,14 +364,17 @@ impl Handle {
                     request = request.gateway(ip);
                 }
 
-                request.execute().await.with_context(|| {
-                    format!(
-                        "Failed to add IP v6 route (src: {}, dst: {}, gtw: {})",
-                        route.get_source(),
-                        route.get_dest(),
-                        route.get_gateway()
-                    )
-                })?;
+                if let Err(rtnetlink::Error::NetlinkError(message)) = request.execute().await {
+                    if Errno::from_i32(message.code.abs()) != Errno::EEXIST {
+                        return Err(anyhow!(
+                            "Failed to add IP v6 route (src: {}, dst: {}, gtw: {},Err: {})",
+                            route.get_source(),
+                            route.get_dest(),
+                            route.get_gateway(),
+                            message
+                        ));
+                    }
+                }
             } else {
                 let dest_addr = if !route.dest.is_empty() {
                     Ipv4Network::from_str(&route.dest)?
@@ -401,7 +405,17 @@ impl Handle {
                     request = request.gateway(ip);
                 }
 
-                request.execute().await?;
+                if let Err(rtnetlink::Error::NetlinkError(message)) = request.execute().await {
+                    if Errno::from_i32(message.code.abs()) != Errno::EEXIST {
+                        return Err(anyhow!(
+                            "Failed to add IP v4 route (src: {}, dst: {}, gtw: {},Err: {})",
+                            route.get_source(),
+                            route.get_dest(),
+                            route.get_gateway(),
+                            message
+                        ));
+                    }
+                }
             }
         }
 
@@ -509,7 +523,7 @@ impl Handle {
             .as_ref()
             .map(|to| to.address.as_str()) // Extract address field
             .and_then(|addr| if addr.is_empty() { None } else { Some(addr) }) // Make sure it's not empty
-            .ok_or(nix::Error::Sys(nix::errno::Errno::EINVAL))?;
+            .ok_or(anyhow!(nix::Error::EINVAL))?;
 
         let ip = IpAddr::from_str(ip_address)
             .map_err(|e| anyhow!("Failed to parse IP {}: {:?}", ip_address, e))?;
@@ -598,12 +612,7 @@ fn parse_mac_address(addr: &str) -> Result<[u8; 6]> {
 
     // Parse single Mac address block
     let mut parse_next = || -> Result<u8> {
-        let v = u8::from_str_radix(
-            split
-                .next()
-                .ok_or(nix::Error::Sys(nix::errno::Errno::EINVAL))?,
-            16,
-        )?;
+        let v = u8::from_str_radix(split.next().ok_or(anyhow!(nix::Error::EINVAL))?, 16)?;
         Ok(v)
     };
 

src/agent/src/network.rs

@@ -5,30 +5,22 @@
 
 use anyhow::{anyhow, Result};
 use nix::mount::{self, MsFlags};
-use protocols::types::{Interface, Route};
 use slog::Logger;
-use std::collections::HashMap;
 use std::fs;
 
 const KATA_GUEST_SANDBOX_DNS_FILE: &str = "/run/kata-containers/sandbox/resolv.conf";
 const GUEST_DNS_FILE: &str = "/etc/resolv.conf";
 
-// Network fully describes a sandbox network with its interfaces, routes and dns
+// Network describes a sandbox network, includings its dns
 // related information.
 #[derive(Debug, Default)]
 pub struct Network {
-    ifaces: HashMap<String, Interface>,
-    routes: Vec<Route>,
     dns: Vec<String>,
 }
 
 impl Network {
     pub fn new() -> Network {
-        Network {
-            ifaces: HashMap::new(),
-            routes: Vec::new(),
-            dns: Vec::new(),
-        }
+        Network { dns: Vec::new() }
     }
 
     pub fn set_dns(&mut self, dns: String) {

src/agent/src/pci.rs

@@ -20,7 +20,7 @@ const FUNCTION_MAX: u8 = (1 << FUNCTION_BITS) - 1;
 
 // Represents a PCI function's slot (a.k.a. device) and function
 // numbers, giving its location on a single logical bus
-#[derive(Copy, Clone, Debug, PartialEq, Eq)]
+#[derive(Copy, Clone, Debug, PartialEq, Eq, Hash)]
 pub struct SlotFn(u8);
 
 impl SlotFn {
@@ -94,7 +94,7 @@ impl fmt::Display for SlotFn {
     }
 }
 
-#[derive(Copy, Clone, Debug, PartialEq, Eq)]
+#[derive(Copy, Clone, Debug, PartialEq, Eq, Hash)]
 pub struct Address {
     domain: u16,
     bus: u8,

src/agent/src/sandbox.rs

@@ -226,6 +226,21 @@ impl Sandbox {
         None
     }
 
+    pub fn find_container_process(&mut self, cid: &str, eid: &str) -> Result<&mut Process> {
+        let ctr = self
+            .get_container(cid)
+            .ok_or_else(|| anyhow!("Invalid container id"))?;
+
+        if eid.is_empty() {
+            return ctr
+                .processes
+                .get_mut(&ctr.init_process_pid)
+                .ok_or_else(|| anyhow!("cannot find init process!"));
+        }
+
+        ctr.get_process(eid).map_err(|_| anyhow!("Invalid exec id"))
+    }
+
     #[instrument]
     pub async fn destroy(&mut self) -> Result<()> {
         for ctr in self.containers.values_mut() {
@@ -450,21 +465,29 @@ fn online_memory(logger: &Logger) -> Result<()> {
 mod tests {
     use super::Sandbox;
     use crate::{mount::baremount, skip_if_not_root};
-    use anyhow::Error;
+    use anyhow::{anyhow, Error};
     use nix::mount::MsFlags;
     use oci::{Linux, Root, Spec};
     use rustjail::container::LinuxContainer;
+    use rustjail::process::Process;
     use rustjail::specconv::CreateOpts;
     use slog::Logger;
     use std::fs::{self, File};
     use std::os::unix::fs::PermissionsExt;
-    use tempfile::Builder;
+    use std::path::Path;
+    use tempfile::{tempdir, Builder, TempDir};
 
     fn bind_mount(src: &str, dst: &str, logger: &Logger) -> Result<(), Error> {
-        baremount(src, dst, "bind", MsFlags::MS_BIND, "", logger)
+        let src_path = Path::new(src);
+        let dst_path = Path::new(dst);
+
+        baremount(src_path, dst_path, "bind", MsFlags::MS_BIND, "", logger)
     }
 
+    use serial_test::serial;
+
     #[tokio::test]
+    #[serial]
     async fn set_sandbox_storage() {
         let logger = slog::Logger::root(slog::Discard, o!());
         let mut s = Sandbox::new(&logger).unwrap();
@@ -499,6 +522,7 @@ mod tests {
     }
 
     #[tokio::test]
+    #[serial]
     async fn remove_sandbox_storage() {
         skip_if_not_root!();
 
@@ -555,6 +579,7 @@ mod tests {
     }
 
     #[tokio::test]
+    #[serial]
     async fn unset_and_remove_sandbox_storage() {
         skip_if_not_root!();
 
@@ -606,6 +631,7 @@ mod tests {
     }
 
     #[tokio::test]
+    #[serial]
     async fn unset_sandbox_storage() {
         let logger = slog::Logger::root(slog::Discard, o!());
         let mut s = Sandbox::new(&logger).unwrap();
@@ -678,22 +704,31 @@ mod tests {
         }
     }
 
-    fn create_linuxcontainer() -> LinuxContainer {
-        LinuxContainer::new(
-            "some_id",
-            "/run/agent",
-            create_dummy_opts(),
-            &slog_scope::logger(),
+    fn create_linuxcontainer() -> (LinuxContainer, TempDir) {
+        // Create a temporal directory
+        let dir = tempdir()
+            .map_err(|e| anyhow!(e).context("tempdir failed"))
+            .unwrap();
+
+        // Create a new container
+        (
+            LinuxContainer::new(
+                "some_id",
+                dir.path().join("rootfs").to_str().unwrap(),
+                create_dummy_opts(),
+                &slog_scope::logger(),
+            )
+            .unwrap(),
+            dir,
         )
-        .unwrap()
     }
 
     #[tokio::test]
+    #[serial]
     async fn get_container_entry_exist() {
-        skip_if_not_root!();
         let logger = slog::Logger::root(slog::Discard, o!());
         let mut s = Sandbox::new(&logger).unwrap();
-        let linux_container = create_linuxcontainer();
+        let (linux_container, _root) = create_linuxcontainer();
 
         s.containers
             .insert("testContainerID".to_string(), linux_container);
@@ -702,6 +737,7 @@ mod tests {
     }
 
     #[tokio::test]
+    #[serial]
     async fn get_container_no_entry() {
         let logger = slog::Logger::root(slog::Discard, o!());
         let mut s = Sandbox::new(&logger).unwrap();
@@ -711,24 +747,24 @@ mod tests {
     }
 
     #[tokio::test]
+    #[serial]
     async fn add_and_get_container() {
-        skip_if_not_root!();
         let logger = slog::Logger::root(slog::Discard, o!());
         let mut s = Sandbox::new(&logger).unwrap();
-        let linux_container = create_linuxcontainer();
+        let (linux_container, _root) = create_linuxcontainer();
 
         s.add_container(linux_container);
         assert!(s.get_container("some_id").is_some());
     }
 
     #[tokio::test]
+    #[serial]
     async fn update_shared_pidns() {
-        skip_if_not_root!();
         let logger = slog::Logger::root(slog::Discard, o!());
         let mut s = Sandbox::new(&logger).unwrap();
         let test_pid = 9999;
 
-        let mut linux_container = create_linuxcontainer();
+        let (mut linux_container, _root) = create_linuxcontainer();
         linux_container.init_process_pid = test_pid;
 
         s.update_shared_pidns(&linux_container).unwrap();
@@ -740,6 +776,7 @@ mod tests {
     }
 
     #[tokio::test]
+    #[serial]
     async fn add_guest_hooks() {
         let logger = slog::Logger::root(slog::Discard, o!());
         let mut s = Sandbox::new(&logger).unwrap();
@@ -763,10 +800,56 @@ mod tests {
     }
 
     #[tokio::test]
+    #[serial]
     async fn test_sandbox_set_destroy() {
         let logger = slog::Logger::root(slog::Discard, o!());
         let mut s = Sandbox::new(&logger).unwrap();
         let ret = s.destroy().await;
         assert!(ret.is_ok());
     }
+
+    #[tokio::test]
+    async fn test_find_container_process() {
+        let logger = slog::Logger::root(slog::Discard, o!());
+        let mut s = Sandbox::new(&logger).unwrap();
+        let cid = "container-123";
+
+        let (mut linux_container, _root) = create_linuxcontainer();
+        linux_container.init_process_pid = 1;
+        linux_container.id = cid.to_string();
+        // add init process
+        linux_container.processes.insert(
+            1,
+            Process::new(&logger, &oci::Process::default(), "1", true, 1).unwrap(),
+        );
+        // add exec process
+        linux_container.processes.insert(
+            123,
+            Process::new(&logger, &oci::Process::default(), "exec-123", false, 1).unwrap(),
+        );
+
+        s.add_container(linux_container);
+
+        // empty exec-id will return init process
+        let p = s.find_container_process(cid, "");
+        assert!(p.is_ok(), "Expecting Ok, Got {:?}", p);
+        let p = p.unwrap();
+        assert_eq!("1", p.exec_id, "exec_id should be 1");
+        assert!(p.init, "init flag should be true");
+
+        // get exist exec-id will return the exec process
+        let p = s.find_container_process(cid, "exec-123");
+        assert!(p.is_ok(), "Expecting Ok, Got {:?}", p);
+        let p = p.unwrap();
+        assert_eq!("exec-123", p.exec_id, "exec_id should be exec-123");
+        assert!(!p.init, "init flag should be false");
+
+        // get not exist exec-id will return error
+        let p = s.find_container_process(cid, "exec-456");
+        assert!(p.is_err(), "Expecting Error, Got {:?}", p);
+
+        // container does not exist
+        let p = s.find_container_process("not-exist-cid", "");
+        assert!(p.is_err(), "Expecting Error, Got {:?}", p);
+    }
 }

src/agent/src/tracer.rs

@@ -3,61 +3,17 @@
 // SPDX-License-Identifier: Apache-2.0
 //
 
-use crate::config::AgentConfig;
 use anyhow::Result;
 use opentelemetry::sdk::propagation::TraceContextPropagator;
 use opentelemetry::{global, sdk::trace::Config, trace::TracerProvider};
-use serde::Deserialize;
 use slog::{info, o, Logger};
 use std::collections::HashMap;
-use std::error::Error;
-use std::fmt;
-use std::str::FromStr;
 use tracing_opentelemetry::OpenTelemetryLayer;
 use tracing_subscriber::layer::SubscriberExt;
 use tracing_subscriber::Registry;
 use ttrpc::r#async::TtrpcContext;
 
-#[derive(Debug, Deserialize, PartialEq)]
-pub enum TraceType {
-    Disabled,
-    Isolated,
-}
-
-#[derive(Debug)]
-pub struct TraceTypeError {
-    details: String,
-}
-
-impl TraceTypeError {
-    fn new(msg: &str) -> TraceTypeError {
-        TraceTypeError {
-            details: msg.into(),
-        }
-    }
-}
-
-impl Error for TraceTypeError {}
-
-impl fmt::Display for TraceTypeError {
-    fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
-        write!(f, "{}", self.details)
-    }
-}
-
-impl FromStr for TraceType {
-    type Err = TraceTypeError;
-
-    fn from_str(s: &str) -> Result<Self, Self::Err> {
-        match s {
-            "isolated" => Ok(TraceType::Isolated),
-            "disabled" => Ok(TraceType::Disabled),
-            _ => Err(TraceTypeError::new("invalid trace type")),
-        }
-    }
-}
-
-pub fn setup_tracing(name: &'static str, logger: &Logger, _agent_cfg: &AgentConfig) -> Result<()> {
+pub fn setup_tracing(name: &'static str, logger: &Logger) -> Result<()> {
     let logger = logger.new(o!("subsystem" => "vsock-tracer"));
 
     let exporter = vsock_exporter::Exporter::builder()

src/agent/src/uevent.rs

@@ -11,7 +11,6 @@ use slog::Logger;
 
 use anyhow::{anyhow, Result};
 use netlink_sys::{protocols, SocketAddr, TokioSocket};
-use nix::errno::Errno;
 use std::fmt::Debug;
 use std::os::unix::io::FromRawFd;
 use std::sync::Arc;
@@ -97,10 +96,18 @@ impl Uevent {
         })
     }
 
+    #[instrument]
+    async fn process_remove(&self, logger: &Logger, sandbox: &Arc<Mutex<Sandbox>>) {
+        let mut sb = sandbox.lock().await;
+        sb.uevent_map.remove(&self.devpath);
+    }
+
     #[instrument]
     async fn process(&self, logger: &Logger, sandbox: &Arc<Mutex<Sandbox>>) {
         if self.action == U_EVENT_ACTION_ADD {
             return self.process_add(logger, sandbox).await;
+        } else if self.action == U_EVENT_ACTION_REMOVE {
+            return self.process_remove(logger, sandbox).await;
         }
         debug!(*logger, "ignoring event"; "uevent" => format!("{:?}", self));
     }
@@ -195,7 +202,7 @@ pub async fn watch_uevents(
                     Ok((buf, addr)) => {
                         if addr.port_number() != 0 {
                             // not our netlink message
-                            let err_msg = format!("{:?}", nix::Error::Sys(Errno::EBADMSG));
+                            let err_msg = format!("{:?}", nix::Error::EBADMSG);
                             error!(logger, "receive uevent message failed"; "error" => err_msg);
                             continue;
                         }
@@ -232,7 +239,6 @@ pub(crate) fn spawn_test_watcher(sandbox: Arc<Mutex<Sandbox>>, uev: Uevent) {
                     if matcher.is_match(&uev) {
                         let (_, sender) = watch.take().unwrap();
                         let _ = sender.send(uev.clone());
-                        return;
                     }
                 }
             });

src/agent/src/util.rs

@@ -3,7 +3,7 @@
 // SPDX-License-Identifier: Apache-2.0
 //
 
-use anyhow::Result;
+use anyhow::{anyhow, Result};
 use futures::StreamExt;
 use std::io;
 use std::io::ErrorKind;
@@ -64,8 +64,12 @@ pub fn get_vsock_incoming(fd: RawFd) -> Incoming {
 
 #[instrument]
 pub async fn get_vsock_stream(fd: RawFd) -> Result<VsockStream> {
-    let stream = get_vsock_incoming(fd).next().await.unwrap()?;
-    Ok(stream)
+    let stream = get_vsock_incoming(fd)
+        .next()
+        .await
+        .ok_or_else(|| anyhow!("cannot handle incoming vsock connection"))?;
+
+    Ok(stream?)
 }
 
 #[cfg(test)]
@@ -124,7 +128,9 @@ mod tests {
 
             let mut vec_locked = vec_ref.lock();
 
-            let v = vec_locked.as_deref_mut().unwrap();
+            let v = vec_locked
+                .as_deref_mut()
+                .map_err(|e| std::io::Error::new(std::io::ErrorKind::Other, e.to_string()))?;
 
             std::io::Write::flush(v)
         }

src/agent/src/watcher.rs

@@ -49,7 +49,7 @@ struct Storage {
     /// the source becomes too large, either in number of files (>16) or total size (>1MB).
     watch: bool,
 
-    /// The list of files to watch from the source mount point and updated in the target one.
+    /// The list of files, directories, symlinks to watch from the source mount point and updated in the target one.
     watched_files: HashMap<PathBuf, SystemTime>,
 }
 
@@ -79,6 +79,20 @@ impl Drop for Storage {
     }
 }
 
+async fn copy(from: impl AsRef<Path>, to: impl AsRef<Path>) -> Result<()> {
+    if fs::symlink_metadata(&from).await?.file_type().is_symlink() {
+        // if source is a symlink, create new symlink with same link source. If
+        // the symlink exists, remove and create new one:
+        if fs::symlink_metadata(&to).await.is_ok() {
+            fs::remove_file(&to).await?;
+        }
+        fs::symlink(fs::read_link(&from).await?, &to).await?;
+    } else {
+        fs::copy(from, to).await?;
+    }
+    Ok(())
+}
+
 impl Storage {
     async fn new(storage: protos::Storage) -> Result<Storage> {
         let entry = Storage {
@@ -93,6 +107,17 @@ impl Storage {
     async fn update_target(&self, logger: &Logger, source_path: impl AsRef<Path>) -> Result<()> {
         let source_file_path = source_path.as_ref();
 
+        // if we are creating a directory: just create it, nothing more to do
+        if source_file_path.symlink_metadata()?.file_type().is_dir() {
+            let dest_file_path = self.make_target_path(&source_file_path)?;
+
+            fs::create_dir_all(&dest_file_path)
+                .await
+                .with_context(|| format!("Unable to mkdir all for {}", dest_file_path.display()))?;
+            return Ok(());
+        }
+
+        // Assume we are dealing with either a file or a symlink now:
         let dest_file_path = if self.source_mount_point.is_file() {
             // Simple file to file copy
             // Assume target mount is a file path
@@ -110,19 +135,13 @@ impl Storage {
             dest_file_path
         };
 
-        debug!(
-            logger,
-            "Copy from {} to {}",
-            source_file_path.display(),
-            dest_file_path.display()
-        );
-        fs::copy(&source_file_path, &dest_file_path)
+        copy(&source_file_path, &dest_file_path)
             .await
             .with_context(|| {
                 format!(
                     "Copy from {} to {} failed",
                     source_file_path.display(),
-                    dest_file_path.display()
+                    dest_file_path.display(),
                 )
             })?;
 
@@ -135,7 +154,7 @@ impl Storage {
         let mut remove_list = Vec::new();
         let mut updated_files: Vec<PathBuf> = Vec::new();
 
-        // Remove deleted files for tracking list
+        // Remove deleted files for tracking list.
         self.watched_files.retain(|st, _| {
             if st.exists() {
                 true
@@ -147,10 +166,19 @@ impl Storage {
 
         // Delete from target
         for path in remove_list {
-            // File has been deleted, remove it from target mount
             let target = self.make_target_path(path)?;
-            debug!(logger, "Removing file from mount: {}", target.display());
-            let _ = fs::remove_file(target).await;
+            // The target may be a directory or a file. If it is a directory that is removed,
+            // we'll remove all files under that directory as well. Because of this, there's a
+            // chance the target (a subdirectory or file under a prior removed target) was already
+            // removed. Make sure we check if the target exists before checking the metadata, and
+            // don't return an error if the remove fails
+            if target.exists() && target.symlink_metadata()?.file_type().is_dir() {
+                debug!(logger, "Removing a directory: {}", target.display());
+                let _ = fs::remove_dir_all(target).await;
+            } else {
+                debug!(logger, "Removing a file: {}", target.display());
+                let _ = fs::remove_file(target).await;
+            }
         }
 
         // Scan new & changed files
@@ -182,15 +210,16 @@ impl Storage {
         let mut size: u64 = 0;
         debug!(logger, "Scanning path: {}", path.display());
 
-        if path.is_file() {
-            let metadata = path
-                .metadata()
-                .with_context(|| format!("Failed to query metadata for: {}", path.display()))?;
+        let metadata = path
+            .symlink_metadata()
+            .with_context(|| format!("Failed to query metadata for: {}", path.display()))?;
 
-            let modified = metadata
-                .modified()
-                .with_context(|| format!("Failed to get modified date for: {}", path.display()))?;
+        let modified = metadata
+            .modified()
+            .with_context(|| format!("Failed to get modified date for: {}", path.display()))?;
 
+        // Treat files and symlinks the same:
+        if path.is_file() || metadata.file_type().is_symlink() {
             size += metadata.len();
 
             // Insert will return old entry if any
@@ -212,6 +241,16 @@ impl Storage {
                 }
             );
         } else {
+            // Handling regular directories - check  to see if this directory is already being tracked, and
+            // track if not:
+            if self
+                .watched_files
+                .insert(path.to_path_buf(), modified)
+                .is_none()
+            {
+                update_list.push(path.to_path_buf());
+            }
+
             // Scan dir recursively
             let mut entries = fs::read_dir(path)
                 .await
@@ -328,8 +367,8 @@ impl SandboxStorages {
                         }
 
                         match baremount(
-                            entry.source_mount_point.to_str().unwrap(),
-                            entry.target_mount_point.to_str().unwrap(),
+                            entry.source_mount_point.as_path(),
+                            entry.target_mount_point.as_path(),
                             "bind",
                             MsFlags::MS_BIND,
                             "bind",
@@ -439,8 +478,8 @@ impl BindWatcher {
         fs::create_dir_all(WATCH_MOUNT_POINT_PATH).await?;
 
         baremount(
-            "tmpfs",
-            WATCH_MOUNT_POINT_PATH,
+            Path::new("tmpfs"),
+            Path::new(WATCH_MOUNT_POINT_PATH),
             "tmpfs",
             MsFlags::empty(),
             "",
@@ -612,7 +651,7 @@ mod tests {
             .unwrap();
 
         // setup storage3: many files, but still watchable
-        for i in 1..MAX_ENTRIES_PER_STORAGE + 1 {
+        for i in 1..MAX_ENTRIES_PER_STORAGE {
             fs::write(src3_path.join(format!("{}.txt", i)), "original").unwrap();
         }
 
@@ -622,6 +661,9 @@ mod tests {
             ..Default::default()
         };
 
+        // delay 20 ms between writes to files in order to ensure filesystem timestamps are unique
+        thread::sleep(Duration::from_millis(20));
+
         entries
             .add(std::iter::once(storage0), &logger)
             .await
@@ -674,7 +716,7 @@ mod tests {
             std::fs::read_dir(entries.0[3].target_mount_point.as_path())
                 .unwrap()
                 .count(),
-            MAX_ENTRIES_PER_STORAGE
+            MAX_ENTRIES_PER_STORAGE - 1
         );
 
         // Add two files to storage 0, verify it is updated without needing to run check:
@@ -692,6 +734,9 @@ mod tests {
             "updated"
         );
 
+        // delay 20 ms between writes to files in order to ensure filesystem timestamps are unique
+        thread::sleep(Duration::from_millis(20));
+
         //
         // Prepare for second check: update mount sources
         //
@@ -744,7 +789,7 @@ mod tests {
             std::fs::read_dir(entries.0[3].target_mount_point.as_path())
                 .unwrap()
                 .count(),
-            MAX_ENTRIES_PER_STORAGE + 1
+            MAX_ENTRIES_PER_STORAGE
         );
 
         // verify that we can remove files as well, but that it isn't observed until check is run
@@ -822,15 +867,20 @@ mod tests {
         fs::remove_file(source_dir.path().join("big.txt")).unwrap();
         fs::remove_file(source_dir.path().join("too-big.txt")).unwrap();
 
-        // Up to 16 files should be okay:
-        for i in 1..MAX_ENTRIES_PER_STORAGE + 1 {
+        assert_eq!(entry.scan(&logger).await.unwrap(), 0);
+
+        // Up to 15 files should be okay (can watch 15 files + 1 directory)
+        for i in 1..MAX_ENTRIES_PER_STORAGE {
             fs::write(source_dir.path().join(format!("{}.txt", i)), "original").unwrap();
         }
 
-        assert_eq!(entry.scan(&logger).await.unwrap(), MAX_ENTRIES_PER_STORAGE);
+        assert_eq!(
+            entry.scan(&logger).await.unwrap(),
+            MAX_ENTRIES_PER_STORAGE - 1
+        );
 
-        // 17 files is too many:
-        fs::write(source_dir.path().join("17.txt"), "updated").unwrap();
+        // 16 files wll be too many:
+        fs::write(source_dir.path().join("16.txt"), "updated").unwrap();
         thread::sleep(Duration::from_secs(1));
 
         // Expect to receive a MountTooManyFiles error
@@ -843,6 +893,180 @@ mod tests {
         }
     }
 
+    #[tokio::test]
+    async fn test_copy() {
+        // prepare tmp src/destination
+        let source_dir = tempfile::tempdir().unwrap();
+        let dest_dir = tempfile::tempdir().unwrap();
+
+        // verify copy of a regular file
+        let src_file = source_dir.path().join("file.txt");
+        let dst_file = dest_dir.path().join("file.txt");
+        fs::write(&src_file, "foo").unwrap();
+        copy(&src_file, &dst_file).await.unwrap();
+        // verify destination:
+        assert!(!fs::symlink_metadata(dst_file)
+            .unwrap()
+            .file_type()
+            .is_symlink());
+
+        // verify copy of a symlink
+        let src_symlink_file = source_dir.path().join("symlink_file.txt");
+        let dst_symlink_file = dest_dir.path().join("symlink_file.txt");
+        tokio::fs::symlink(&src_file, &src_symlink_file)
+            .await
+            .unwrap();
+        copy(src_symlink_file, &dst_symlink_file).await.unwrap();
+        // verify destination:
+        assert!(fs::symlink_metadata(&dst_symlink_file)
+            .unwrap()
+            .file_type()
+            .is_symlink());
+        assert_eq!(fs::read_link(&dst_symlink_file).unwrap(), src_file);
+        assert_eq!(fs::read_to_string(&dst_symlink_file).unwrap(), "foo");
+    }
+
+    #[tokio::test]
+    async fn watch_directory_verify_dir_removal() {
+        let source_dir = tempfile::tempdir().unwrap();
+        let dest_dir = tempfile::tempdir().unwrap();
+
+        let mut entry = Storage::new(protos::Storage {
+            source: source_dir.path().display().to_string(),
+            mount_point: dest_dir.path().display().to_string(),
+            ..Default::default()
+        })
+        .await
+        .unwrap();
+        let logger = slog::Logger::root(slog::Discard, o!());
+
+        // create a path we'll remove later
+        fs::create_dir_all(source_dir.path().join("tmp")).unwrap();
+        fs::write(&source_dir.path().join("tmp/test-file"), "foo").unwrap();
+        assert_eq!(entry.scan(&logger).await.unwrap(), 3); // root, ./tmp, test-file
+
+        // Verify expected directory, file:
+        assert_eq!(
+            std::fs::read_dir(dest_dir.path().join("tmp"))
+                .unwrap()
+                .count(),
+            1
+        );
+        assert_eq!(std::fs::read_dir(&dest_dir).unwrap().count(), 1);
+
+        // Now, remove directory, and verify that the directory (and its file) are removed:
+        fs::remove_dir_all(source_dir.path().join("tmp")).unwrap();
+        thread::sleep(Duration::from_secs(1));
+        assert_eq!(entry.scan(&logger).await.unwrap(), 0);
+
+        assert_eq!(std::fs::read_dir(&dest_dir).unwrap().count(), 0);
+
+        assert_eq!(entry.scan(&logger).await.unwrap(), 0);
+    }
+
+    #[tokio::test]
+    async fn watch_directory_with_symlinks() {
+        // Prepare source directory:
+        // ..2021_10_29_03_10_48.161654083/file.txt
+        // ..data -> ..2021_10_29_03_10_48.161654083
+        // file.txt -> ..data/file.txt
+
+        let source_dir = tempfile::tempdir().unwrap();
+        let actual_dir = source_dir.path().join("..2021_10_29_03_10_48.161654083");
+        let actual_file = actual_dir.join("file.txt");
+        let sym_dir = source_dir.path().join("..data");
+        let sym_file = source_dir.path().join("file.txt");
+
+        let relative_to_dir = PathBuf::from("..2021_10_29_03_10_48.161654083");
+
+        // create backing file/path
+        fs::create_dir_all(&actual_dir).unwrap();
+        fs::write(&actual_file, "two").unwrap();
+
+        // create indirection symlink directory that points to the directory that holds the actual file:
+        tokio::fs::symlink(&relative_to_dir, &sym_dir)
+            .await
+            .unwrap();
+
+        // create presented data file symlink:
+        tokio::fs::symlink(PathBuf::from("..data/file.txt"), sym_file)
+            .await
+            .unwrap();
+
+        let dest_dir = tempfile::tempdir().unwrap();
+
+        // delay 20 ms between writes to files in order to ensure filesystem timestamps are unique
+        thread::sleep(Duration::from_millis(20));
+
+        let mut entry = Storage::new(protos::Storage {
+            source: source_dir.path().display().to_string(),
+            mount_point: dest_dir.path().display().to_string(),
+            ..Default::default()
+        })
+        .await
+        .unwrap();
+
+        let logger = slog::Logger::root(slog::Discard, o!());
+
+        assert_eq!(entry.scan(&logger).await.unwrap(), 5);
+
+        // Should copy no files since nothing is changed since last check
+        assert_eq!(entry.scan(&logger).await.unwrap(), 0);
+
+        // now what, what is updated?
+        fs::write(actual_file, "updated").unwrap();
+
+        // delay 20 ms between writes to files in order to ensure filesystem timestamps are unique
+        thread::sleep(Duration::from_millis(20));
+
+        assert_eq!(entry.scan(&logger).await.unwrap(), 1);
+
+        assert_eq!(
+            fs::read_to_string(dest_dir.path().join("file.txt")).unwrap(),
+            "updated"
+        );
+
+        // Verify that resulting file.txt is a symlink:
+        assert!(
+            tokio::fs::symlink_metadata(dest_dir.path().join("file.txt"))
+                .await
+                .unwrap()
+                .file_type()
+                .is_symlink()
+        );
+
+        // Verify that .data directory is a symlink:
+        assert!(tokio::fs::symlink_metadata(&dest_dir.path().join("..data"))
+            .await
+            .unwrap()
+            .file_type()
+            .is_symlink());
+
+        // Should copy no new files after copy happened
+        assert_eq!(entry.scan(&logger).await.unwrap(), 0);
+
+        // Now, simulate configmap update.
+        //  - create a new actual dir/file,
+        //  - update the symlink directory to point to this one
+        //  - remove old dir/file
+        let new_actual_dir = source_dir.path().join("..2021_10_31");
+        let new_actual_file = new_actual_dir.join("file.txt");
+        fs::create_dir_all(&new_actual_dir).unwrap();
+        fs::write(&new_actual_file, "new configmap").unwrap();
+
+        tokio::fs::remove_file(&sym_dir).await.unwrap();
+        tokio::fs::symlink(PathBuf::from("..2021_10_31"), &sym_dir)
+            .await
+            .unwrap();
+        tokio::fs::remove_dir_all(&actual_dir).await.unwrap();
+
+        assert_eq!(entry.scan(&logger).await.unwrap(), 3); // file, file-dir, symlink
+        assert_eq!(
+            fs::read_to_string(dest_dir.path().join("file.txt")).unwrap(),
+            "new configmap"
+        );
+    }
+
     #[tokio::test]
     async fn watch_directory() {
         // Prepare source directory:
@@ -853,6 +1077,13 @@ mod tests {
         fs::create_dir_all(source_dir.path().join("A/B")).unwrap();
         fs::write(source_dir.path().join("A/B/1.txt"), "two").unwrap();
 
+        // A/C is an empty directory
+        let empty_dir = "A/C";
+        fs::create_dir_all(source_dir.path().join(empty_dir)).unwrap();
+
+        // delay 20 ms between writes to files in order to ensure filesystem timestamps are unique
+        thread::sleep(Duration::from_millis(20));
+
         let dest_dir = tempfile::tempdir().unwrap();
 
         let mut entry = Storage::new(protos::Storage {
@@ -865,13 +1096,14 @@ mod tests {
 
         let logger = slog::Logger::root(slog::Discard, o!());
 
-        assert_eq!(entry.scan(&logger).await.unwrap(), 2);
+        assert_eq!(entry.scan(&logger).await.unwrap(), 6);
+
+        // check empty directory
+        assert!(dest_dir.path().join(empty_dir).exists());
 
         // Should copy no files since nothing is changed since last check
         assert_eq!(entry.scan(&logger).await.unwrap(), 0);
 
-        // Should copy 1 file
-        thread::sleep(Duration::from_secs(1));
         fs::write(source_dir.path().join("A/B/1.txt"), "updated").unwrap();
         assert_eq!(entry.scan(&logger).await.unwrap(), 1);
         assert_eq!(
@@ -879,12 +1111,21 @@ mod tests {
             "updated"
         );
 
+        // delay 20 ms between writes to files in order to ensure filesystem timestamps are unique
+        thread::sleep(Duration::from_millis(20));
+
         // Should copy no new files after copy happened
         assert_eq!(entry.scan(&logger).await.unwrap(), 0);
 
         // Update another file
         fs::write(source_dir.path().join("1.txt"), "updated").unwrap();
         assert_eq!(entry.scan(&logger).await.unwrap(), 1);
+
+        // create another empty directory A/C/D
+        let empty_dir = "A/C/D";
+        fs::create_dir_all(source_dir.path().join(empty_dir)).unwrap();
+        assert_eq!(entry.scan(&logger).await.unwrap(), 1);
+        assert!(dest_dir.path().join(empty_dir).exists());
     }
 
     #[tokio::test]
@@ -909,7 +1150,9 @@ mod tests {
 
         assert_eq!(entry.scan(&logger).await.unwrap(), 1);
 
-        thread::sleep(Duration::from_secs(1));
+        // delay 20 ms between writes to files in order to ensure filesystem timestamps are unique
+        thread::sleep(Duration::from_millis(20));
+
         fs::write(&source_file, "two").unwrap();
         assert_eq!(entry.scan(&logger).await.unwrap(), 1);
         assert_eq!(fs::read_to_string(&dest_file).unwrap(), "two");
@@ -935,8 +1178,9 @@ mod tests {
 
         let logger = slog::Logger::root(slog::Discard, o!());
 
-        assert_eq!(entry.scan(&logger).await.unwrap(), 1);
-        assert_eq!(entry.watched_files.len(), 1);
+        // expect the root directory and the file:
+        assert_eq!(entry.scan(&logger).await.unwrap(), 2);
+        assert_eq!(entry.watched_files.len(), 2);
 
         assert!(target_file.exists());
         assert!(entry.watched_files.contains_key(&source_file));
@@ -946,7 +1190,7 @@ mod tests {
 
         assert_eq!(entry.scan(&logger).await.unwrap(), 0);
 
-        assert_eq!(entry.watched_files.len(), 0);
+        assert_eq!(entry.watched_files.len(), 1);
         assert!(!target_file.exists());
     }
 
@@ -979,7 +1223,10 @@ mod tests {
         );
     }
 
+    use serial_test::serial;
+
     #[tokio::test]
+    #[serial]
     async fn create_tmpfs() {
         skip_if_not_root!();
 
@@ -989,11 +1236,14 @@ mod tests {
         watcher.mount(&logger).await.unwrap();
         assert!(is_mounted(WATCH_MOUNT_POINT_PATH).unwrap());
 
+        thread::sleep(Duration::from_millis(20));
+
         watcher.cleanup();
         assert!(!is_mounted(WATCH_MOUNT_POINT_PATH).unwrap());
     }
 
     #[tokio::test]
+    #[serial]
     async fn spawn_thread() {
         skip_if_not_root!();
 
@@ -1023,6 +1273,7 @@ mod tests {
     }
 
     #[tokio::test]
+    #[serial]
     async fn verify_container_cleanup_watching() {
         skip_if_not_root!();
 

src/agent/vsock-exporter/Cargo.toml

@@ -7,7 +7,7 @@ edition = "2018"
 # See more keys and their definitions at https://doc.rust-lang.org/cargo/reference/manifest.html
 
 [dependencies]
-nix = "0.21.0"
+nix = "0.23.0"
 libc = "0.2.94"
 thiserror = "1.0.26"
 opentelemetry = { version = "0.14.0", features=["serialize"] }
@@ -15,6 +15,6 @@ serde = { version = "1.0.126", features = ["derive"] }
 tokio-vsock = "0.3.1"
 bincode = "1.3.3"
 byteorder = "1.4.3"
-slog = { version = "2.5.2", features = ["dynamic-keys", "max_level_trace", "release_max_level_info"] }
+slog = { version = "2.5.2", features = ["dynamic-keys", "max_level_trace", "release_max_level_debug"] }
 async-trait = "0.1.50"
 tokio = "1.2.0"

src/libs/logging/Cargo.lock

@@ -0,0 +1,321 @@
+# This file is automatically @generated by Cargo.
+# It is not intended for manual editing.
+version = 3
+
+[[package]]
+name = "arc-swap"
+version = "1.5.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "c5d78ce20460b82d3fa150275ed9d55e21064fc7951177baacf86a145c4a4b1f"
+
+[[package]]
+name = "autocfg"
+version = "1.0.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "cdb031dd78e28731d87d56cc8ffef4a8f36ca26c38fe2de700543e627f8a464a"
+
+[[package]]
+name = "bitflags"
+version = "1.3.2"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "bef38d45163c2f1dde094a7dfd33ccf595c92905c8f8f4fdc18d06fb1037718a"
+
+[[package]]
+name = "cfg-if"
+version = "1.0.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "baf1de4339761588bc0619e3cbc0120ee582ebb74b53b4efbf79117bd2da40fd"
+
+[[package]]
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+source = "registry+https://github.com/rust-lang/crates.io-index"
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+dependencies = [
+ "libc",
+ "num-integer",
+ "num-traits",
+ "time",
+ "winapi",
+]
+
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+name = "crossbeam-channel"
+version = "0.5.1"
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+checksum = "06ed27e177f16d65f0f0c22a213e17c696ace5dd64b14258b52f9417ccb52db4"
+dependencies = [
+ "cfg-if",
+ "crossbeam-utils",
+]
+
+[[package]]
+name = "crossbeam-utils"
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+dependencies = [
+ "cfg-if",
+ "lazy_static",
+]
+
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+dependencies = [
+ "cfg-if",
+ "libc",
+ "wasi",
+]
+
+[[package]]
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+source = "registry+https://github.com/rust-lang/crates.io-index"
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+
+[[package]]
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+
+[[package]]
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+checksum = "1b03d17f364a3a042d5e5d46b053bbbf82c92c9430c592dd4c064dc6ee997125"
+
+[[package]]
+name = "logging"
+version = "0.1.0"
+dependencies = [
+ "serde_json",
+ "slog",
+ "slog-async",
+ "slog-json",
+ "slog-scope",
+ "tempfile",
+]
+
+[[package]]
+name = "num-integer"
+version = "0.1.44"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "d2cc698a63b549a70bc047073d2949cce27cd1c7b0a4a862d08a8031bc2801db"
+dependencies = [
+ "autocfg",
+ "num-traits",
+]
+
+[[package]]
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+dependencies = [
+ "autocfg",
+]
+
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+
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+
+[[package]]
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+checksum = "2e7573632e6454cf6b99d7aac4ccca54be06da05aca2ef7423d22d27d4d4bcd8"
+dependencies = [
+ "libc",
+ "rand_chacha",
+ "rand_core",
+ "rand_hc",
+]
+
+[[package]]
+name = "rand_chacha"
+version = "0.3.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "e6c10a63a0fa32252be49d21e7709d4d4baf8d231c2dbce1eaa8141b9b127d88"
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+ "ppv-lite86",
+ "rand_core",
+]
+
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+ "getrandom",
+]
+
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+ "rand_core",
+]
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+ "bitflags",
+]
+
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+ "winapi",
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+ "ryu",
+ "serde",
+]
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+dependencies = [
+ "crossbeam-channel",
+ "slog",
+ "take_mut",
+ "thread_local",
+]
+
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+ "serde_json",
+ "slog",
+]
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+ "arc-swap",
+ "lazy_static",
+ "slog",
+]
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+ "cfg-if",
+ "libc",
+ "rand",
+ "redox_syscall",
+ "remove_dir_all",
+ "winapi",
+]
+
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+version = "1.1.3"
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+ "once_cell",
+]
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+ "libc",
+ "winapi",
+]
+
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+
+[[package]]
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+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "5c839a674fcd7a98952e593242ea400abe93992746761e38641405d28b00f419"
+dependencies = [
+ "winapi-i686-pc-windows-gnu",
+ "winapi-x86_64-pc-windows-gnu",
+]
+
+[[package]]
+name = "winapi-i686-pc-windows-gnu"
+version = "0.4.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
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+
+[[package]]
+name = "winapi-x86_64-pc-windows-gnu"
+version = "0.4.0"
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src/libs/logging/Cargo.toml

@@ -7,15 +7,15 @@ edition = "2018"
 # See more keys and their definitions at https://doc.rust-lang.org/cargo/reference/manifest.html
 
 [dependencies]
-serde_json = "1.0.39"
+serde_json = "1.0.73"
 # slog:
 # - Dynamic keys required to allow HashMap keys to be slog::Serialized.
 # - The 'max_*' features allow changing the log level at runtime
 #   (by stopping the compiler from removing log calls).
-slog = { version = "2.5.2", features = ["dynamic-keys", "max_level_trace", "release_max_level_info"] }
-slog-json = "2.3.0"
-slog-async = "2.3.0"
-slog-scope = "4.1.2"
+slog = { version = "2.7.0", features = ["dynamic-keys", "max_level_trace", "release_max_level_debug"] }
+slog-json = "2.4.0"
+slog-async = "2.7.0"
+slog-scope = "4.4.0"
 
 [dev-dependencies]
-tempfile = "3.1.0"
+tempfile = "3.2.0"

src/libs/logging/Makefile

@@ -0,0 +1,18 @@
+# Copyright (c) 2021 Intel Corporation
+#
+# SPDX-License-Identifier: Apache-2.0
+#
+
+# It is not necessary to have a build target as this crate is built
+# automatically by the consumers of it.
+#
+# However, it is essential that the crate be tested.
+default: test
+
+# It is essential to run these tests using *both* build profiles.
+# See the `test_logger_levels()` test for further information.
+test:
+	@echo "INFO: testing log levels for development build"
+	@cargo test
+	@echo "INFO: testing log levels for release build"
+	@cargo test --release

src/libs/logging/src/lib.rs

@@ -20,6 +20,8 @@ const LOG_LEVELS: &[(&str, slog::Level)] = &[
     ("critical", slog::Level::Critical),
 ];
 
+const DEFAULT_SUBSYSTEM: &str = "root";
+
 // XXX: 'writer' param used to make testing possible.
 pub fn create_logger<W>(
     name: &str,
@@ -50,7 +52,7 @@ where
     let logger = slog::Logger::root(
         async_drain.fuse(),
         o!("version" => env!("CARGO_PKG_VERSION"),
-            "subsystem" => "root",
+            "subsystem" => DEFAULT_SUBSYSTEM,
             "pid" => process::id().to_string(),
             "name" => name.to_string(),
             "source" => source.to_string()),
@@ -216,8 +218,8 @@ where
 #[cfg(test)]
 mod tests {
     use super::*;
-    use serde_json::Value;
-    use slog::info;
+    use serde_json::{json, Value};
+    use slog::{crit, debug, error, info, warn, Logger};
     use std::io::prelude::*;
     use tempfile::NamedTempFile;
 
@@ -295,15 +297,15 @@ mod tests {
                 let result_level = result.unwrap();
                 let expected_level = d.result.unwrap();
 
-                assert!(result_level == expected_level, msg);
+                assert!(result_level == expected_level, "{}", msg);
                 continue;
             } else {
-                assert!(result.is_err(), msg);
+                assert!(result.is_err(), "{}", msg);
             }
 
-            let expected_error = format!("{}", d.result.as_ref().unwrap_err());
-            let actual_error = format!("{}", result.unwrap_err());
-            assert!(actual_error == expected_error, msg);
+            let expected_error = d.result.as_ref().unwrap_err();
+            let actual_error = result.unwrap_err();
+            assert!(&actual_error == expected_error, "{}", msg);
         }
     }
 
@@ -350,13 +352,13 @@ mod tests {
             let msg = format!("{}, result: {:?}", msg, result);
 
             if d.result.is_ok() {
-                assert!(result == d.result, msg);
+                assert!(result == d.result, "{}", msg);
                 continue;
             }
 
-            let expected_error = format!("{}", d.result.as_ref().unwrap_err());
-            let actual_error = format!("{}", result.unwrap_err());
-            assert!(actual_error == expected_error, msg);
+            let expected_error = d.result.as_ref().unwrap_err();
+            let actual_error = result.unwrap_err();
+            assert!(&actual_error == expected_error, "{}", msg);
         }
     }
 
@@ -376,14 +378,17 @@ mod tests {
         let record_key = "record-key-1";
         let record_value = "record-key-2";
 
-        let logger = create_logger(name, source, level, writer);
+        let (logger, guard) = create_logger(name, source, level, writer);
 
         let msg = "foo, bar, baz";
 
         // Call the logger (which calls the drain)
-        info!(logger, "{}", msg; "subsystem" => record_subsystem, record_key => record_value);
+        // Note: This "mid level" log level should be available in debug or
+        // release builds.
+        info!(&logger, "{}", msg; "subsystem" => record_subsystem, record_key => record_value);
 
         // Force temp file to be flushed
+        drop(guard);
         drop(logger);
 
         let mut contents = String::new();
@@ -430,4 +435,168 @@ mod tests {
             .expect("failed to find record key field");
         assert_eq!(field_record_value, record_value);
     }
+
+    #[test]
+    fn test_logger_levels() {
+        let name = "name";
+        let source = "source";
+
+        let debug_msg = "a debug log level message";
+        let info_msg = "an info log level message";
+        let warn_msg = "a warn log level message";
+        let error_msg = "an error log level message";
+        let critical_msg = "a critical log level message";
+
+        // The slog crate will *remove* macro calls for log levels "above" the
+        // configured log level.lock
+        //
+        // At the time of writing, the default slog log
+        // level is "info", but this crate overrides that using the magic
+        // "*max_level*" features in the "Cargo.toml" manifest.
+
+        // However, there are two log levels:
+        //
+        // - max_level_${level}
+        //
+        //   This is the log level for normal "cargo build" (development/debug)
+        //   builds.
+        //
+        // - release_max_level_${level}
+        //
+        //   This is the log level for "cargo install" and
+        //   "cargo build --release" (release) builds.
+        //
+        // This crate sets them to different values, which is sensible and
+        // standard practice. However, that causes a problem: there is
+        // currently no clean way for this test code to detect _which_
+        // profile the test is being built for (development or release),
+        // meaning we cannot know which macros are expected to produce output
+        // and which aren't ;(
+        //
+        // The best we can do is test the following log levels which
+        // are expected to work in all build profiles.
+
+        let debug_closure = |logger: &Logger, msg: String| debug!(logger, "{}", msg);
+        let info_closure = |logger: &Logger, msg: String| info!(logger, "{}", msg);
+        let warn_closure = |logger: &Logger, msg: String| warn!(logger, "{}", msg);
+        let error_closure = |logger: &Logger, msg: String| error!(logger, "{}", msg);
+        let critical_closure = |logger: &Logger, msg: String| crit!(logger, "{}", msg);
+
+        struct TestData<'a> {
+            slog_level: slog::Level,
+            slog_level_tag: &'a str,
+            msg: String,
+            closure: Box<dyn Fn(&Logger, String)>,
+        }
+
+        let tests = &[
+            TestData {
+                slog_level: slog::Level::Debug,
+                // Looks like a typo but tragically it isn't! ;(
+                slog_level_tag: "DEBG",
+                msg: debug_msg.into(),
+                closure: Box::new(debug_closure),
+            },
+            TestData {
+                slog_level: slog::Level::Info,
+                slog_level_tag: "INFO",
+                msg: info_msg.into(),
+                closure: Box::new(info_closure),
+            },
+            TestData {
+                slog_level: slog::Level::Warning,
+                slog_level_tag: "WARN",
+                msg: warn_msg.into(),
+                closure: Box::new(warn_closure),
+            },
+            TestData {
+                slog_level: slog::Level::Error,
+                // Another language tragedy
+                slog_level_tag: "ERRO",
+                msg: error_msg.into(),
+                closure: Box::new(error_closure),
+            },
+            TestData {
+                slog_level: slog::Level::Critical,
+                slog_level_tag: "CRIT",
+                msg: critical_msg.into(),
+                closure: Box::new(critical_closure),
+            },
+        ];
+
+        for (i, d) in tests.iter().enumerate() {
+            let msg = format!("test[{}]", i);
+
+            // Create a writer for the logger drain to use
+            let writer =
+                NamedTempFile::new().expect(&format!("{:}: failed to create tempfile", msg));
+
+            // Used to check file contents before the temp file is unlinked
+            let mut writer_ref = writer
+                .reopen()
+                .expect(&format!("{:?}: failed to clone tempfile", msg));
+
+            let (logger, logger_guard) = create_logger(name, source, d.slog_level, writer);
+
+            // Call the logger (which calls the drain)
+            (d.closure)(&logger, d.msg.to_owned());
+
+            // Force temp file to be flushed
+            drop(logger_guard);
+            drop(logger);
+
+            let mut contents = String::new();
+            writer_ref
+                .read_to_string(&mut contents)
+                .expect(&format!("{:?}: failed to read tempfile contents", msg));
+
+            // Convert file to JSON
+            let fields: Value = serde_json::from_str(&contents)
+                .expect(&format!("{:?}: failed to convert logfile to json", msg));
+
+            // Check the expected JSON fields
+
+            let field_ts = fields
+                .get("ts")
+                .expect(&format!("{:?}: failed to find timestamp field", msg));
+            assert_ne!(field_ts, "", "{}", msg);
+
+            let field_version = fields
+                .get("version")
+                .expect(&format!("{:?}: failed to find version field", msg));
+            assert_eq!(field_version, env!("CARGO_PKG_VERSION"), "{}", msg);
+
+            let field_pid = fields
+                .get("pid")
+                .expect(&format!("{:?}: failed to find pid field", msg));
+            assert_ne!(field_pid, "", "{}", msg);
+
+            let field_level = fields
+                .get("level")
+                .expect(&format!("{:?}: failed to find level field", msg));
+            assert_eq!(field_level, d.slog_level_tag, "{}", msg);
+
+            let field_msg = fields
+                .get("msg")
+                .expect(&format!("{:?}: failed to find msg field", msg));
+            assert_eq!(field_msg, &json!(d.msg), "{}", msg);
+
+            let field_name = fields
+                .get("name")
+                .expect(&format!("{:?}: failed to find name field", msg));
+            assert_eq!(field_name, name, "{}", msg);
+
+            let field_source = fields
+                .get("source")
+                .expect(&format!("{:?}: failed to find source field", msg));
+            assert_eq!(field_source, source, "{}", msg);
+
+            let field_subsystem = fields
+                .get("subsystem")
+                .expect(&format!("{:?}: failed to find subsystem field", msg));
+
+            // No explicit subsystem, so should be the default
+            assert_eq!(field_subsystem, &json!(DEFAULT_SUBSYSTEM), "{}", msg);
+        }
+    }
 }

src/libs/oci/Cargo.toml

@@ -5,7 +5,7 @@ authors = ["The Kata Containers community <kata-dev@lists.katacontainers.io>"]
 edition = "2018"
 
 [dependencies]
-serde = "1.0.91"
-serde_derive = "1.0.91"
-serde_json = "1.0.39"
-libc = "0.2.58"
+serde = "1.0.131"
+serde_derive = "1.0.131"
+serde_json = "1.0.73"
+libc = "0.2.112"

src/libs/protocols/Cargo.toml

@@ -4,10 +4,16 @@ version = "0.1.0"
 authors = ["The Kata Containers community <kata-dev@lists.katacontainers.io>"]
 edition = "2018"
 
+[features]
+default = []
+with-serde = [ "serde", "serde_json" ]
+
 [dependencies]
 ttrpc = { version = "0.5.0", features = ["async"] }
 async-trait = "0.1.42"
-protobuf = "=2.14.0"
+protobuf = { version = "=2.14.0", features = ["with-serde"] }
+serde = { version = "1.0.130", features = ["derive"], optional = true }
+serde_json = { version = "1.0.68", optional = true }
 
 [build-dependencies]
 ttrpc-codegen = "0.2.0"

src/libs/protocols/build.rs

@@ -0,0 +1,168 @@
+// Copyright (c) 2020 Ant Group
+//
+// SPDX-License-Identifier: Apache-2.0
+//
+
+use std::fs::File;
+use std::io::{BufRead, BufReader, Read, Write};
+use std::path::Path;
+use std::process::exit;
+use ttrpc_codegen::{Codegen, Customize, ProtobufCustomize};
+
+fn replace_text_in_file(file_name: &str, from: &str, to: &str) -> Result<(), std::io::Error> {
+    let mut src = File::open(file_name)?;
+    let mut contents = String::new();
+    src.read_to_string(&mut contents).unwrap();
+    drop(src);
+
+    let new_contents = contents.replace(from, to);
+
+    let mut dst = File::create(&file_name)?;
+    dst.write_all(new_contents.as_bytes())?;
+
+    Ok(())
+}
+
+fn use_serde(protos: &[&str], out_dir: &Path) -> Result<(), std::io::Error> {
+    protos
+        .iter()
+        .try_for_each(|f: &&str| -> Result<(), std::io::Error> {
+            let out_file = Path::new(f)
+                .file_name()
+                .and_then(|s| s.to_str())
+                .ok_or(format!("failed to get proto file name for {:?}", f))
+                .map(|s| {
+                    let t = s.replace(".proto", ".rs");
+                    out_dir.join(t)
+                })
+                .map_err(|e| std::io::Error::new(std::io::ErrorKind::Other, e))?
+                .to_str()
+                .ok_or(format!("cannot convert {:?} path to string", f))
+                .map_err(|e| std::io::Error::new(std::io::ErrorKind::Other, e))?
+                .to_string();
+
+            replace_text_in_file(
+                &out_file,
+                "derive(Serialize, Deserialize)",
+                "derive(serde::Serialize, serde::Deserialize)",
+            )
+        })
+}
+
+fn handle_file(autogen_comment: &str, rust_filename: &str) -> Result<(), std::io::Error> {
+    let mut new_contents = Vec::new();
+
+    let file = File::open(rust_filename)?;
+
+    let reader = BufReader::new(file);
+
+    // Guard the code since it is only needed for the agent-ctl tool,
+    // not the agent itself.
+    let serde_default_code = r#"#[cfg_attr(feature = "with-serde", serde(default))]"#;
+
+    for line in reader.lines() {
+        let line = line?;
+
+        new_contents.push(line.clone());
+
+        let pattern = "//! Generated file from";
+
+        if line.starts_with(&pattern) {
+            new_contents.push(autogen_comment.into());
+        }
+
+        let struct_pattern = "pub struct ";
+
+        // Although we've requested serde support via `Customize`, to
+        // allow the `kata-agent-ctl` tool to partially deserialise structures
+        // specified in JSON, we need this bit of additional magic.
+        if line.starts_with(&struct_pattern) {
+            new_contents.insert(new_contents.len() - 1, serde_default_code.trim().into());
+        }
+    }
+
+    let data = new_contents.join("\n");
+
+    let mut dst = File::create(&rust_filename)?;
+
+    dst.write_all(data.as_bytes())?;
+
+    Ok(())
+}
+
+fn real_main() -> Result<(), std::io::Error> {
+    let autogen_comment = format!("\n//! Generated by {:?} ({:?})", file!(), module_path!());
+
+    let protos = vec![
+        "protos/agent.proto",
+        "protos/google/protobuf/empty.proto",
+        "protos/health.proto",
+        "protos/oci.proto",
+        "protos/types.proto",
+    ];
+
+    // Tell Cargo that if the .proto files changed, to rerun this build script.
+    protos
+        .iter()
+        .for_each(|p| println!("cargo:rerun-if-changed={}", &p));
+
+    let ttrpc_options = Customize {
+        async_server: true,
+        ..Default::default()
+    };
+
+    let protobuf_options = ProtobufCustomize {
+        serde_derive: Some(true),
+        ..Default::default()
+    };
+
+    let out_dir = Path::new("src");
+
+    Codegen::new()
+        .out_dir(out_dir)
+        .inputs(&protos)
+        .include("protos")
+        .customize(ttrpc_options)
+        .rust_protobuf()
+        .rust_protobuf_customize(protobuf_options)
+        .run()?;
+
+    for file in protos.iter() {
+        let proto_filename = Path::new(file).file_name().unwrap();
+
+        let generated_file = proto_filename
+            .to_str()
+            .ok_or("failed")
+            .map_err(|e| std::io::Error::new(std::io::ErrorKind::Other, e))?
+            .replace(".proto", ".rs");
+
+        let out_file = out_dir.join(generated_file);
+
+        let out_file_str = out_file
+            .to_str()
+            .ok_or("failed")
+            .map_err(|e| std::io::Error::new(std::io::ErrorKind::Other, e))?;
+
+        handle_file(&autogen_comment, out_file_str)?;
+    }
+
+    // There is a message named 'Box' in oci.proto
+    // so there is a struct named 'Box', we should replace Box<Self> to ::std::boxed::Box<Self>
+    // to avoid the conflict.
+    replace_text_in_file(
+        "src/oci.rs",
+        "self: Box<Self>",
+        "self: ::std::boxed::Box<Self>",
+    )?;
+
+    use_serde(&protos, out_dir)?;
+
+    Ok(())
+}
+
+fn main() {
+    if let Err(e) = real_main() {
+        eprintln!("ERROR: {}", e);
+        exit(1);
+    }
+}

src/libs/protocols/protos/agent.proto

@@ -52,8 +52,6 @@ service AgentService {
 	rpc AddARPNeighbors(AddARPNeighborsRequest) returns (google.protobuf.Empty);
 
 	// observability
-	rpc StartTracing(StartTracingRequest) returns (google.protobuf.Empty);
-	rpc StopTracing(StopTracingRequest) returns (google.protobuf.Empty);
 	rpc GetMetrics(GetMetricsRequest) returns (Metrics);
 
 	// misc (TODO: some rpcs can be replaced by hyperstart-exec)
@@ -492,12 +490,6 @@ message CopyFileRequest {
 	bytes data = 8;
 }
 
-message StartTracingRequest {
-}
-
-message StopTracingRequest {
-}
-
 message GetOOMEventRequest {}
 
 message OOMEvent {