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

[Jörg Rödel]

On Wed, Jun 17, 2026 at 06:37:52AM -0700, Sean Christopherson wrote:
> Ok, so it took us a few times to learn our lesson.  I still don't see that as a
> strong argument for new uAPI, especially not for VMSA pages.  I am very firmly
> of the opinion that letting anything but the host kernel configure the VMSA is
> beyond stupid, but unfortunately we're stuck with AP_CREATION.  Expanding that
> surface has a very, very, VERY high bar to get over.

The strongest argument in my view (and the main reason we are doing this) is
actually the predictable launch measurement. On SEV-SNP this is a requirement
to use platform VM-identity features like the ID Block.

-Joerg