Re: [PATCH 3/3] x86/sev: The code for returning to user space is also in syscall gap

Joerg Roedel
2021-12-17T11:00:44Z

On Fri, Dec 17, 2021 at 11:30:10AM +0100, Borislav Petkov wrote:
> I audited the handful instructions in there and didn't find anything
> that would cause a #VC...

If the hypervisor decides to mess with the code-page for this path
while a CPU is executing it. This will cause a #VC on that CPU and that
could hit in the syscall return path.

Regards,

--
Jörg Rödel
jroedel@suse.de

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