Hi Alejandro,
> On Oct 13, 2023, at 01:25, Alejandro Vallejo <alejandro.vallejo@cloud.com> wrote:
>
> This patch should make it to 4.18, as it prevents random crashes on AMD
> Zen4 running outdated microcode.
Yes I agree, so for this series:
Release-acked-by: Henry Wang <Henry.Wang@arm.com>
Kind regards,
Henry
>
> Under certain conditions Zen4 may corrupt its own code stream when SMT is
> enabled and STIBP is not. The Linux thread in which this was highlighted is
> in patch2's commit message.
>
> NOTE: Still running in CI as of now, but tested locally. Pipeline here.
> https://gitlab.com/xen-project/people/agvallejo/xen/-/pipelines/1034895039
>
> Patch 1: is just a minor refactor to ensure we don't get microarchitectures
> of different families mixed up now that we have 3 different
> families involved (Fam17h, Fam18h and Fam19h)
> Patch 2: The actual fix. It involves setting a bit in an MSR if it's a non
> virtualized zen4. It's not a direct copy of the Linux patch, as we
> have started using macros to find out microarchitectures from
> CPUID bits, rather than relying on models.
>
> Alejandro Vallejo (2):
> xen/x86: Add family guards to the is_zen[12]_uarch() macros
> x86/amd: Prevent potentially fetching wrong instruction bytes on Zen4
>
> xen/arch/x86/cpu/amd.c | 16 +++++++++++++---
> xen/arch/x86/include/asm/amd.h | 17 +++++++++++++----
> xen/arch/x86/include/asm/msr-index.h | 2 ++
> xen/arch/x86/spec_ctrl.c | 3 ---
> 4 files changed, 28 insertions(+), 10 deletions(-)
>
> --
> 2.34.1
>