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Message-ID: <f13f2736-626a-267b-db38-70a81872a325@redhat.com>
Date:   Thu, 7 Apr 2022 14:12:28 +0200
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Subject: Re: [RFC PATCH v5 101/104] KVM: TDX: Silently ignore INIT/SIPI
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To:     Xiaoyao Li <xiaoyao.li@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>,
        Tom Lendacky <thomas.lendacky@amd.com>
References: <cover.1646422845.git.isaku.yamahata@intel.com>
 <d0eb8fa53e782a244397168df856f9f904e4d1cd.1646422845.git.isaku.yamahata@intel.com>
 <efbe06a7-3624-2a5a-c1c4-be86f63951e3@redhat.com>
 <48ab3a81-a353-e6ee-7718-69c260c9ea17@intel.com>
From:   Paolo Bonzini <pbonzini@redhat.com>
In-Reply-To: <48ab3a81-a353-e6ee-7718-69c260c9ea17@intel.com>
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On 4/7/22 13:09, Xiaoyao Li wrote:
> On 4/5/2022 11:48 PM, Paolo Bonzini wrote:
>> On 3/4/22 20:49, isaku.yamahata@intel.com wrote:
>>> +        if (kvm_init_sipi_unsupported(vcpu->kvm))
>>> +            /*
>>> +             * TDX doesn't support INIT.  Ignore INIT event.  In the
>>> +             * case of SIPI, the callback of
>>> +             * vcpu_deliver_sipi_vector ignores it.
>>> +             */
>>>               vcpu->arch.mp_state = KVM_MP_STATE_RUNNABLE;
>>> -        else
>>> -            vcpu->arch.mp_state = KVM_MP_STATE_INIT_RECEIVED;
>>> +        else {
>>> +            kvm_vcpu_reset(vcpu, true);
>>> +            if (kvm_vcpu_is_bsp(apic->vcpu))
>>> +                vcpu->arch.mp_state = KVM_MP_STATE_RUNNABLE;
>>> +            else
>>> +                vcpu->arch.mp_state = KVM_MP_STATE_INIT_RECEIVED;
>>> +        }
>>
>> Should you check vcpu->arch.guest_state_protected instead of 
>> special-casing TDX? 
> 
> We cannot use vcpu->arch.guest_state_protected because TDX supports 
> debug TD, of which the states are not protected.
> 
> At least we need another flag, I think.

Let's add .deliver_init to the kvm_x86_ops then.

Paolo