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Date:   Tue, 20 Jul 2021 22:09:28 +0000
From:   Sean Christopherson <seanjc@google.com>
To:     Brijesh Singh <brijesh.singh@amd.com>
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Subject: Re: [PATCH Part2 RFC v4 38/40] KVM: SVM: Provide support for
 SNP_GUEST_REQUEST NAE event
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On Tue, Jul 20, 2021, Brijesh Singh wrote:
> 
> On 7/20/21 11:28 AM, Sean Christopherson wrote:
> > Out of curiosity, why 4 VMPCKs?  It seems completely arbitrary.
> > 
> 
> I believe the thought process was by providing 4 keys it can provide
> flexibility for each VMPL levels to use a different keys (if they wish). The
> firmware does not care about the vmpl level during the guest request
> handling, it just want to know which key is used for encrypting the payload
> so that he can decrypt and provide the  response for it.

Ah, I forgot about VMPLs.  That makes sense.

Thanks!