Re: [PATCH 3/3] KVM: SVM: Sync GPRs to the GHCB only after VMGEXIT

[Sean Christopherson]

On Fri, Jan 22, 2021, Tom Lendacky wrote:
> On 1/22/21 5:50 PM, Sean Christopherson wrote:
> > Sync GPRs to the GHCB on VMRUN only if a sync is needed, i.e. if the
> > previous exit was a VMGEXIT and the guest is expecting some data back.
> > 
> 
> The start of sev_es_sync_to_ghcb() checks if the GHCB has been mapped, which
> only occurs on VMGEXIT, and exits early if not. And sev_es_sync_from_ghcb()
> is only called if the GHCB has been successfully mapped. The only thing in
> between is sev_es_validate_vmgexit(), which will terminate the VM on error.
> So I don't think this patch is needed.

Ah, nice!  Yep, this can be dropped.  Thanks!