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.

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