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Message-ID: <9cfd5d2f-55e4-f8fc-701b-5917941e0269@redhat.com>
Date:   Wed, 6 Apr 2022 13:27:27 +0200
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Subject: Re: [RFC PATCH v5 027/104] KVM: TDX: initialize VM with TDX specific
 parameters
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To:     Xiaoyao Li <xiaoyao.li@intel.com>, Kai Huang <kai.huang@intel.com>,
        isaku.yamahata@intel.com, kvm@vger.kernel.org,
        linux-kernel@vger.kernel.org
Cc:     isaku.yamahata@gmail.com, Jim Mattson <jmattson@google.com>,
        erdemaktas@google.com, Connor Kuehl <ckuehl@redhat.com>,
        Sean Christopherson <seanjc@google.com>
References: <cover.1646422845.git.isaku.yamahata@intel.com>
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 <36df723c-4794-69a8-8d12-ea371a7865df@intel.com>
From:   Paolo Bonzini <pbonzini@redhat.com>
In-Reply-To: <36df723c-4794-69a8-8d12-ea371a7865df@intel.com>
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On 4/6/22 04:06, Xiaoyao Li wrote:
>>
>> Indeed, it would be easier to use the existing cpuid data in struct 
>> kvm_vcpu, because right now there is no way to ensure that they are 
>> consistent.
>>
>> Why is KVM_SET_CPUID2 not enough?  Are there any modifications done by 
>> KVM that affect the measurement?
> 
> Then we get the situation that KVM_TDX_INIT_VM must be called after 1 
> vcpu is created. It seems illogical that it has chance to fail the VM 
> scope initialization after 1 vcpu is successfully created.

I see.  Yeah, it makes sense to have the CPUID in KVM_TDX_INIT_VM then.

Paolo