Re: [PATCH] KVM: SVM: Do not terminate SEV-ES guests on GHCB validation failure

[Peter Gonda]

On Fri, May 14, 2021 at 1:22 PM Tom Lendacky <thomas.lendacky@xxxxxxx> wrote:
>
> Currently, an SEV-ES guest is terminated if the validation of the VMGEXIT
> exit code and parameters fail. Since the VMGEXIT instruction can be issued
> from userspace, even though userspace (likely) can't update the GHCB,
> don't allow userspace to be able to kill the guest.
>
> Return a #GP request through the GHCB when validation fails, rather than
> terminating the guest.

Is this a gap in the spec? I don't see anything that details what
should happen if the correct fields for NAE are not set in the first
couple paragraphs of section 4 'GHCB Protocol'.