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

[Sean Christopherson]

On Thu, Jun 11, 2026, Jörg Rödel wrote:
> From: Joerg Roedel <joerg.roedel@xxxxxxx>
> 
> 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 why
this needs to be handled in KVM.  I understand most of the words and acronyms,
but that's about where my understanding stops.