Sender: Paolo Bonzini <paolo.bonzini@gmail.com>
Message-ID: <4708e92c-373b-a07f-c80c-fe194ca706df@redhat.com>
Date:   Thu, 25 Nov 2021 21:50:39 +0100
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Subject: Re: [RFC PATCH v3 28/59] KVM: x86: Check for pending APICv interrupt
 in kvm_vcpu_has_events()
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To:     isaku.yamahata@intel.com, Thomas Gleixner <tglx@linutronix.de>,
        Ingo Molnar <mingo@redhat.com>, Borislav Petkov <bp@alien8.de>,
        "H . Peter Anvin" <hpa@zytor.com>,
        Vitaly Kuznetsov <vkuznets@redhat.com>,
        Wanpeng Li <wanpengli@tencent.com>,
        Jim Mattson <jmattson@google.com>,
        Joerg Roedel <joro@8bytes.org>, erdemaktas@google.com,
        Connor Kuehl <ckuehl@redhat.com>,
        Sean Christopherson <seanjc@google.com>,
        linux-kernel@vger.kernel.org, kvm@vger.kernel.org
Cc:     isaku.yamahata@gmail.com,
        Sean Christopherson <sean.j.christopherson@intel.com>
References: <cover.1637799475.git.isaku.yamahata@intel.com>
 <9852ad79d1078088743a57008226c869b0316da1.1637799475.git.isaku.yamahata@intel.com>
From:   Paolo Bonzini <pbonzini@redhat.com>
In-Reply-To: <9852ad79d1078088743a57008226c869b0316da1.1637799475.git.isaku.yamahata@intel.com>
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On 11/25/21 01:20, isaku.yamahata@intel.com wrote:
> From: Sean Christopherson<sean.j.christopherson@intel.com>
> 
> Return true for kvm_vcpu_has_events() if the vCPU has a pending APICv
> interrupt to support TDX's usage of APICv.  Unlike VMX, TDX doesn't have
> access to vmcs.GUEST_INTR_STATUS and so can't emulate posted interrupts,
> i.e. needs to generate a posted interrupt and more importantly can't
> manually move requested interrupts into the vIRR (which it also doesn't
> have access to).

Does this mean it is impossible to disable APICv on TDX?  If so, please 
add a WARN.

Paolo