From 8f4f51c47fa2176c59fd8d3c3ccfcb23dbe685c9 Mon Sep 17 00:00:00 2001 From: Rolf Neugebauer Date: Wed, 4 Apr 2018 19:27:59 +0100 Subject: [PATCH] docs: Clarify s390x support and add details for hvf mode on macOS Signed-off-by: Rolf Neugebauer --- docs/platform-qemu.md | 17 ++++++++++++----- 1 file changed, 12 insertions(+), 5 deletions(-) diff --git a/docs/platform-qemu.md b/docs/platform-qemu.md index 94ac325ff..c5a64b4e0 100644 --- a/docs/platform-qemu.md +++ b/docs/platform-qemu.md @@ -4,19 +4,26 @@ The `qemu` backend is the most versatile `run` backend for `linuxkit`. It can boot both `x86_64` and `arm64` images, runs on macOS and Linux (and possibly Windows), and can boot most types of output formats. On Linux, `kvm` acceleration is enabled by default if -available. +available. On macOS, `hvf` acceleration (using the Hypervisor +framework) is used if your `qemu` version supports it (versions +released after Jan/Feb 2018 should support it). `s390x` is currently +only supported in `kvm` mode as the emulated `s390x` architecture (aka +`tcg` mode) does not seem to support several required platform +features. Further, on `s390x` platforms you need to set +`vm.allocate_pgste=1` via `sysctl` (or use `echo 1 > +/proc/sys/vm/allocate_pgste`). ## Boot By default `linuxkit run qemu` will boot with the host architecture -(`x86_64` on `x86_64` machines and `aarch64` on `arm64` systems). The -architecture can be specified with `-arch` and currently accepts -`x86_64` and `aarch64` as arguments. +(e.g., `aarch64` on `arm64` systems). The architecture can be +specified with `-arch` and currently accepts `x86_64`, `aarch64`, and +`s390x` as arguments. `linuxkit run qemu` can boot in different types of images: -- `kernel+initrd`: This is the default mode of `linuxkit run qemu` [`x86_64`, `arm64`] +- `kernel+initrd`: This is the default mode of `linuxkit run qemu` [`x86_64`, `arm64`, `s390x`] - `iso-bios`: `linuxkit run qemu -iso ` [`x86_64`] - `iso-efi`: `linuxkit run qemu -iso -uefi `. This looks in `/usr/share/ovmf/bios.bin` for the EFI firmware by default. Can be overwritten with `-fw`. [`x86_64`, `arm64`] - `qcow-bios`: `linuxkit run qemu disk.qcow2` [`x86_64`]