Re: Should SEV-ES #VC use IST? (Re: [PATCH] Allow RDTSC and RDTSCP from userspace)

Borislav Petkov
2020-06-23T16:10:24Z

On Tue, Jun 23, 2020 at 04:32:22PM +0100, Andrew Cooper wrote:
> MSR_MCG_STATUS.MCIP, and yes - any #MC before that point will
> immediately Shutdown.  Any #MC between that point and IRET will clobber
> its IST stack and end up sad.

Well, at some point we should simply accept that we're living a little
on the edge. That is, until we get IRET with a mask of to-reenable
vectors which has #MC, NMI and whatever else vectors. It would be even
better if that mask were configurable.

--
Regards/Gruss,
Boris.