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Message-ID: <7c71c294-8ce4-4f13-b827-d16a8811739a@linux.intel.com>
Date: Fri, 19 Apr 2024 16:31:54 +0800
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Subject: Re: [PATCH v19 117/130] KVM: TDX: Silently ignore INIT/SIPI
To: isaku.yamahata@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
References: <cover.1708933498.git.isaku.yamahata@intel.com>
 <4a4225de42be0f7568c5ecb5c22f2029f8e91d62.1708933498.git.isaku.yamahata@intel.com>
From: Binbin Wu <binbin.wu@linux.intel.com>
In-Reply-To: <4a4225de42be0f7568c5ecb5c22f2029f8e91d62.1708933498.git.isaku.yamahata@intel.com>
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On 2/26/2024 4:26 PM, isaku.yamahata@intel.com wrote:
> From: Isaku Yamahata <isaku.yamahata@intel.com>
>
> The TDX module API doesn't provide API for VMM to inject INIT IPI and SIPI.
> Instead it defines the different protocols to boot application processors.
> Ignore INIT and SIPI events for the TDX guest.
>
> There are two options. 1) (silently) ignore INIT/SIPI request or 2) return
> error to guest TDs somehow.  Given that TDX guest is paravirtualized to
> boot AP, the option 1 is chosen for simplicity.
>
> Signed-off-by: Isaku Yamahata <isaku.yamahata@intel.com>
> ---
[...]
> +
> +static void vt_vcpu_deliver_init(struct kvm_vcpu *vcpu)
> +{
> +	if (is_td_vcpu(vcpu)) {
> +		/* TDX doesn't support INIT.  Ignore INIT event */
> +		vcpu->arch.mp_state = KVM_MP_STATE_RUNNABLE;
Why change the mp_state to KVM_MP_STATE_RUNNABLE here?

And I am not sure whether we can say the INIT event is ignored since 
mp_state could be modified.

> +		return;
> +	}
> +
> +	kvm_vcpu_deliver_init(vcpu);
> +}
> +