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Date: Wed, 17 Jun 2026 15:28:57 +0200
From: =?utf-8?B?SsO2cmcgUsO2ZGVs?= <joro@8bytes.org>
To: James Bottomley <James.Bottomley@hansenpartnership.com>
Cc: Sean Christopherson <seanjc@google.com>, 
	Paolo Bonzini <pbonzini@redhat.com>, x86@kernel.org, Tom Lendacky <thomas.lendacky@amd.com>, 
	Michael Roth <michael.roth@amd.com>, kvm@vger.kernel.org, linux-kernel@vger.kernel.org, 
	coconut-svsm@lists.linux.dev, Joerg Roedel <joerg.roedel@amd.com>, 
	Jethro Beekman <jethro@fortanix.com>
Subject: Re: [PATCH 4/4] kvm: svm: Support KVM_SEV_SNP_PAGE_TYPE_VMSA at
 SNP_LAUNCH_UPDATE
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In-Reply-To: <64383a438eb79a30588f2737a6df84f9d4cd5b7d.camel@HansenPartnership.com>

Hi James,

On Wed, Jun 17, 2026 at 09:18:14AM -0400, James Bottomley wrote:
> That's true for the launch measure, but you do have a vTPM inside the
> SVSM which you could use to measure an updated GHCB if we could decide
> on a PCR to use (and a logging specification).

I guess you mean an updated VMSA? The guest-created VMSAs are trusted because
they are created by trusted code from within the TEE. There is no need to
runtime-measure their content, no?


-Joerg