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Date: Wed, 10 Apr 2024 17:27:28 -0500
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Subject: Re: [PATCH v12 28/29] crypto: ccp: Add the
 SNP_{PAUSE,RESUME}_ATTESTATION commands
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To: Michael Roth <michael.roth@amd.com>, kvm@vger.kernel.org
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References: <20240329225835.400662-1-michael.roth@amd.com>
 <20240329225835.400662-29-michael.roth@amd.com>
From: Tom Lendacky <thomas.lendacky@amd.com>
In-Reply-To: <20240329225835.400662-29-michael.roth@amd.com>
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On 3/29/24 17:58, Michael Roth wrote:
> These commands can be used to pause servicing of guest attestation
> requests. This useful when updating the reported TCB or signing key with
> commands such as SNP_SET_CONFIG/SNP_COMMIT/SNP_VLEK_LOAD, since they may
> in turn require updates to userspace-supplied certificates, and if an
> attestation request happens to be in-flight at the time those updates
> are occurring there is potential for a guest to receive a certificate
> blob that is out of sync with the effective signing key for the
> attestation report.
> 
> These interfaces also provide some versatility with how similar
> firmware/certificate update activities can be handled in the future.
> 
> Signed-off-by: Michael Roth <michael.roth@amd.com>

Reviewed-by: Tom Lendacky <thomas.lendacky@amd.com>

> ---