Re: [PATCH 1/2] KVM: x86: Add emulation support for #GP triggered by VM instructions

From: Maxim Levitsky
Date: Thu Jan 14 2021 - 06:43:48 EST


On Tue, 2021-01-12 at 23:15 -0600, Wei Huang wrote:
>
> On 1/12/21 12:58 PM, Andy Lutomirski wrote:
> > Andrew Cooper points out that there may be a nicer workaround. Make
> > sure that the SMRAM and HT region (FFFD00000000 - FFFFFFFFFFFF) are
> > marked as reserved in the guest, too.
>
> In theory this proposed solution can avoid intercepting #GP. But in
> reality SMRAM regions can be different on different machines. So this
> solution can break after VM migration.
>
I should add to this, that on my 3970X,
I just noticed that the problematic SMRAM region moved on
its own (likely due to the fact that I moved some pcie cards around recently).

Best regards,
Maxim Levitsky