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Sampat wrote: >>> @@ -849,6 +850,18 @@ static int wakeup_cpu_via_vmgexit(u32 apic_id, unsigned long start_ip, unsigned >>> vmsa->vmpl = snp_vmpl; >>> vmsa->sev_features = sev_status >> 2; >>> >>> + if (sev_status & MSR_AMD64_SEV_SNP_ENABLED && >>> + (sev_status & MSR_AMD64_SNP_ESMT_PROT)) { >>> + vmsa->vcpu_id = apic_id; >>> + /* >>> + * The mask fully set puts every vCPU in one group, so any two >>> + * of them may be co-resident. A legal ESMTP sibling must >>> + * also match on ASID, so the sibling of a vCPU in guest mode is >>> + * always either another vCPU of this same guest or idle. >>> + */ >> >> This comment doesn't belong here. >> Ack, will get rid of it. >> In any case, this set touches multiple trees so I'm open to suggestions from >> KVM folks how we should do the patch merging tetris eventually. > > Post and merge the guest patches separately, and put any architectural collateral > need for the guest code in those patches. This is not high on my todo list, i.e. > the KVM patches can come later. Sure this makes sense. In that case I'm thinking of splitting the patches by flipping the order as follows: Series 1 1. x86/sev: Add Enhanced SMT Protection fields to the VMSA (new) Moves the vcpu_id and vcpu_sibling_mask VMSA definitions out of the KVM patch so the guest side builds on its own. 2. Current guest support patch - no change, minus the comment 3. Hyper-V guest support patch - no change, may need the blessing from Hyper-V folks to merge Series 2 - to kvm later 1. KVM: SVM: Re-queue events that were never injected (unchanged) 2. KVM: SVM: Add host support for Enhanced SMT Protection - Unchanged apart from dropping the VMSA definitions now in series 1 Boris, series 2 still carries the X86_FEATURE_AMD_ESMTP/scattered.c entry and MSR_AMD64_IDLE_WAKEUP_ICR, which only KVM uses. I'll keep your ack on those so they can go through the KVM tree. Thanks, --Pratik