Re: [PATCH 4/4] kvm: svm: Support KVM_SEV_SNP_PAGE_TYPE_VMSA at SNP_LAUNCH_UPDATE

Sean Christopherson <[email protected]> Thu, 11 Jun 2026 05:43:05 -0700
Newsgroups dev.linux.lists.coconut-svsm,org.kernel.vger.kvm,org.kernel.vger.linux-kernel
Message-ID <[email protected]>
On Thu, Jun 11, 2026, J=C3=B6rg R=C3=B6del wrote:
> From: Joerg Roedel <[email protected]>
>=20
> Support setting a VMSA in guest physical memory during the SEV-SNP
> launch process. Only one VMSA can be provided which will then be used
> for the BSP. All of the APs will not have a VMSA allocated or assigned
> when this feature is used.
>
> This ensures stable launch measurements on SEV-SNP which are
> independent of the number of VCPUs the VM is launched with.

This needs a *much* longer explanation and more justification for exactly w=
hy
this needs to be handled in KVM.  I understand most of the words and acrony=
ms,
but that's about where my understanding stops.