Re: [PATCH kernel v2 2/3] KVM: SEV: Enable data breakpoints in SEV-ES

From: Borislav Petkov
Date: Thu Jan 12 2023 - 06:38:19 EST


On Thu, Jan 12, 2023 at 04:45:34PM +1100, Alexey Kardashevskiy wrote:
> Well, SEV-ES KVM (ES == Encrypted State) does not save/restore them for the
> guest (well, as I would expect) as the guest registers are not visible to
> host to save, they are intercepted and the VM does this GHCB dance with
> VMGEXIT(SVM_EXIT_WRITE_DR7).

But they're saved in the VMSA, as Table B-3 says.

> Well, the only place in APM is that "Table B-3. Swap Types and the AMD APM
> volume 2", and it is pretty brief, do I miss something?

I don't understand that question - please elaborate.

Thx.

--
Regards/Gruss,
Boris.

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