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Message-ID: <f0f41485-3013-4aa7-ad8f-6e6c7acfe364@linux.intel.com>
Date: Mon, 8 Apr 2024 11:16:24 +0800
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Subject: Re: [PATCH v19 091/130] KVM: TDX: remove use of struct vcpu_vmx from
 posted_interrupt.c
To: Isaku Yamahata <isaku.yamahata@intel.com>, Chao Gao <chao.gao@intel.com>
Cc: kvm@vger.kernel.org, linux-kernel@vger.kernel.org,
 isaku.yamahata@gmail.com, Paolo Bonzini <pbonzini@redhat.com>,
 erdemaktas@google.com, Sean Christopherson <seanjc@google.com>,
 Sagi Shahar <sagis@google.com>, Kai Huang <kai.huang@intel.com>,
 chen.bo@intel.com, hang.yuan@intel.com, tina.zhang@intel.com,
 isaku.yamahata@linux.intel.com
References: <cover.1708933498.git.isaku.yamahata@intel.com>
 <6c7774a44515d6787c9512cb05c3b305e9b5855c.1708933498.git.isaku.yamahata@intel.com>
 <ZgUmdIM67dybDTCn@chao-email>
 <20240328211036.GS2444378@ls.amr.corp.intel.com>
From: Binbin Wu <binbin.wu@linux.intel.com>
In-Reply-To: <20240328211036.GS2444378@ls.amr.corp.intel.com>
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On 3/29/2024 5:10 AM, Isaku Yamahata wrote:
> On Thu, Mar 28, 2024 at 04:12:36PM +0800,
> Chao Gao <chao.gao@intel.com> wrote:
>
>>> }
>>>
>>> void vmx_vcpu_pi_put(struct kvm_vcpu *vcpu)
>>> @@ -200,7 +222,8 @@ void vmx_vcpu_pi_put(struct kvm_vcpu *vcpu)
>>> 	if (!vmx_needs_pi_wakeup(vcpu))
>>> 		return;
>>>
>>> -	if (kvm_vcpu_is_blocking(vcpu) && !vmx_interrupt_blocked(vcpu))
>>> +	if (kvm_vcpu_is_blocking(vcpu) &&
>>> +	    (is_td_vcpu(vcpu) || !vmx_interrupt_blocked(vcpu)))
>> Ditto.
>>
>> This looks incorrect to me. here we assume interrupt is always enabled for TD.
>> But on TDVMCALL(HLT), the guest tells KVM if hlt is called with interrupt
>> disabled. KVM can just check that interrupt status passed from the guest.
> That's true.  We can complicate this function and HLT emulation.  But I don't
> think it's worthwhile because HLT with interrupt masked is rare.  Only for
> CPU online.
Then, it's better to add some comments?