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SubjectRe: [PATCH v2 00/13] SMM implementation for KVM


On 29/05/2015 21:03, Radim Krčmář wrote:
> I found a corner case that doesn't fit any specific patch:
>
> We allow INIT while in SMM. This brings some security complications as
> we also don't reset hflags (another long standing bug?), but we don't
> really need to because INIT in SMM is against the spec anyway;
> APM May 2013 2:10.3.3 Exceptions and Interrupts,
> • INIT—The processor does not recognize INIT while in SMM.
>
> SDM April 2015: 34.5.1 Initial SMM Execution Environment,
> Maskable hardware interrupts, exceptions, NMI interrupts, SMI
> interrupts, A20M interrupts, single-step traps, breakpoint traps, and
> INIT operations are inhibited when the processor enters SMM.
>
> And there is no mention of an exception for INIT.
> (Some extra old experiments say that INIT could be enabled, but that is
> not applicable now, http://www.rcollins.org/ddj/Mar97/Mar97.html)
>
> I think that INIT received before RSM should be delivered after.

Yes. I'll look at it next week and post a 14th patch.

Paolo


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