Re: [PATCH] x86/sev: Fully map the #VC exception stacks

[Tom Lendacky]

On 9/30/21 11:40 PM, Tom Lendacky wrote:
> The size of the exception stacks was recently increased, resulting in
> stack sizes greater than a page in size. The #VC exception handling was
> only mapping the first (bottom) page, resulting in an SEV-ES guest failing
> to boot.
>
> Update setup_vc_stacks() to map all the pages of both the IST stack area
> and the fallback stack area.
>
> Fixes: 7fae4c24a2b8 ("x86: Increase exception stack sizes")

Arguably the Fixes: tag may not be completely accurate, since it was an 
issue within setup_vc_stacks(). But, this is more for if someone was to 
pull the patch identified by the Fixes: tag, then they would definitely 
need this patch to run SEV-ES.

Thanks,
Tom

> Signed-off-by: Tom Lendacky <thomas.lendacky@xxxxxxx>
> ---
>   arch/x86/kernel/sev.c | 24 ++++++++++++++++--------
>   1 file changed, 16 insertions(+), 8 deletions(-)