Re: [PATCH 3/3] x86/sev: The code for returning to user space is also in syscall gap
From: Joerg Roedel
Date: Fri Dec 17 2021 - 06:00:45 EST
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
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