Re: [PATCH] x86/sev: Fix kernel crash due to late update to read-only ghcb_version

[Tom Lendacky]

On 11/30/23 03:30, Ingo Molnar wrote:
> * Ashwin Dayanand Kamat <kashwindayan@xxxxxxxxxx> wrote:
>
> > From: Ashwin Dayanand Kamat <ashwin.kamat@xxxxxxxxxxxx>
> >
> > kernel crash was observed because of page fault, while running
> > cpuhotplug ltp testcases on SEV-ES enabled systems. The crash was
> > observed during hotplug after the CPU was offlined and the process
> > was migrated to different cpu. setup_ghcb() is called again which
> > tries to update ghcb_version in sev_es_negotiate_protocol(). Ideally this
> > is a read_only variable which is initialised during booting.
> > This results in pagefault.
>
> Applied to tip:x86/urgent, thanks.
>
> Tom: I've added your Suggested-by and Acked-by, which appeared to be the
> case given the v1 discussion, let me know if that's not accurate.

All good.

Thanks,
Tom

> I've also tidied up the changelog - final version attached below.
>
> Thanks,
>
> 	Ingo