8bbcb06af5
Under certain circumstances[0] Kata will attempt to use SHPC hotplug for PCI devices on the guest. In fact we explicitly enable SHPC on our PCI to PCI bridges, regardless of the qemu default. SHPC was designed a long, long time ago for physical hotplugging and works very poorly for a virtual environment. In particular it has a mandatory 5s delay to allow a (real, human) operator to back out the operation if they press a button by mistake. This alone makes it unusable for a fast start up application like Kata. Worse, the agent forces a PCI rescan during startup. That will race with the SHPC hotplug operation causing the device to go into a bad state where config space can't be accessed from the guest at all. The only reason we've sort of gotten away with this is that our default guest kernel configuration triggers what's arguably a kernel bug effectively disabling SHPC. That makes the agent rescan the only reason we see the new device. Now that we require a qemu >=6.1, which includes ACPI PCI hotplug on the q35 machine, we can explicitly disable SHPC in all cases. It's nothing but trouble. fixes #2174 Signed-off-by: David Gibson <david@gibson.dropbear.id.au> |
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| .github/workflows | ||
| ci | ||
| docs | ||
| pkg/logging | ||
| snap | ||
| src | ||
| tools | ||
| utils | ||
| .gitignore | ||
| CODE_OF_CONDUCT.md | ||
| CODEOWNERS | ||
| CONTRIBUTING.md | ||
| Glossary.md | ||
| LICENSE | ||
| Makefile | ||
| README.md | ||
| utils.mk | ||
| VERSION | ||
| versions.yaml | ||
Kata Containers
Welcome to Kata Containers!
This repository is the home of the Kata Containers code for the 2.0 and newer releases.
If you want to learn about Kata Containers, visit the main Kata Containers website.
Introduction
Kata Containers is an open source project and community working to build a standard implementation of lightweight Virtual Machines (VMs) that feel and perform like containers, but provide the workload isolation and security advantages of VMs.
Getting started
See the installation documentation.
Documentation
See the official documentation (including installation guides, the developer guide, design documents and more).
Community
To learn more about the project, its community and governance, see the community repository. This is the first place to go if you wish to contribute to the project.
Getting help
See the community section for ways to contact us.
Raising issues
Please raise an issue in this repository.
Note: If you are reporting a security issue, please follow the vulnerability reporting process
Developers
Components
Main components
The table below lists the core parts of the project:
| Component | Type | Description |
|---|---|---|
| runtime | core | Main component run by a container manager and providing a containerd shimv2 runtime implementation. |
| agent | core | Management process running inside the virtual machine / POD that sets up the container environment. |
| documentation | documentation | Documentation common to all components (such as design and install documentation). |
| tests | tests | Excludes unit tests which live with the main code. |
Additional components
The table below lists the remaining parts of the project:
| Component | Type | Description |
|---|---|---|
| packaging | infrastructure | Scripts and metadata for producing packaged binaries (components, hypervisors, kernel and rootfs). |
| kernel | kernel | Linux kernel used by the hypervisor to boot the guest image. Patches are stored here. |
| osbuilder | infrastructure | Tool to create "mini O/S" rootfs and initrd images and kernel for the hypervisor. |
agent-ctl |
utility | Tool that provides low-level access for testing the agent. |
trace-forwarder |
utility | Agent tracing helper. |
ci |
CI | Continuous Integration configuration files and scripts. |
katacontainers.io |
Source for the katacontainers.io site. |
Packaging and releases
Kata Containers is now available natively for most distributions. However, packaging scripts and metadata are still used to generate snap and GitHub releases. See the components section for further details.