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Subject: Re: [RFC] KVM: x86: Support KVM VMs sharing SEV context
To:     Sean Christopherson <seanjc@google.com>,
        Nathan Tempelman <natet@google.com>
Cc:     Thomas Lendacky <thomas.lendacky@amd.com>, x86@kernel.org,
        kvm@vger.kernel.org, linux-kernel@vger.kernel.org,
        Steve Rutherford <srutherford@google.com>,
        David Rientjes <rientjes@google.com>,
        Brijesh Singh <brijesh.singh@amd.com>,
        Ashish Kalra <Ashish.Kalra@amd.com>
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From:   Paolo Bonzini <pbonzini@redhat.com>
Message-ID: <df2e2cd9-18d5-f35e-6c05-5ba0c399ccbe@redhat.com>
Date:   Tue, 16 Mar 2021 18:58:42 +0100
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On 16/03/21 18:52, Sean Christopherson wrote:
>> I don't
>> know that holding the fd instead of the kvm makes that much better though,
>> are there advantages to that I'm not seeing?
> If there's no kvm pointer, it's much more difficult for someone to do the wrong
> thing, and any such shenanigans stick out like a sore thumb in patches, which
> makes reviewing future changes easier.

On the other hand holding the fd open complicates the code, reference 
counting rules are already hard enough.

I think we only need a replacement for "mirror", what about "dependent"? 
  "is_dependent_enc_context" seems clear enough.

Paolo