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In-Reply-To: <dbf8648ee18606a5a450bce32100771a3de5fd83.1637799475.git.isaku.yamahata@intel.com>
From:   Lai Jiangshan <jiangshanlai@gmail.com>
Date:   Mon, 29 Nov 2021 10:49:23 +0800
Message-ID: <CAJhGHyDgPv==-H55GDuzXzQcioaw5xb-2skUbzDfyODaUVwimA@mail.gmail.com>
Subject: Re: [RFC PATCH v3 16/59] KVM: x86: Add per-VM flag to disable direct
 IRQ injection
To:     isaku.yamahata@intel.com
Cc:     Thomas Gleixner <tglx@linutronix.de>,
        Ingo Molnar <mingo@redhat.com>, Borislav Petkov <bp@alien8.de>,
        "H . Peter Anvin" <hpa@zytor.com>,
        Paolo Bonzini <pbonzini@redhat.com>,
        Vitaly Kuznetsov <vkuznets@redhat.com>,
        Wanpeng Li <wanpengli@tencent.com>,
        Jim Mattson <jmattson@google.com>,
        Joerg Roedel <joro@8bytes.org>,
        Erdem Aktas <erdemaktas@google.com>,
        Connor Kuehl <ckuehl@redhat.com>,
        Sean Christopherson <seanjc@google.com>,
        LKML <linux-kernel@vger.kernel.org>, kvm@vger.kernel.org,
        isaku.yamahata@gmail.com,
        Sean Christopherson <sean.j.christopherson@intel.com>
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On Fri, Nov 26, 2021 at 3:44 PM <isaku.yamahata@intel.com> wrote:

>  static int dm_request_for_irq_injection(struct kvm_vcpu *vcpu)
>  {
>         return vcpu->run->request_interrupt_window &&
> +              !vcpu->kvm->arch.irq_injection_disallowed &&
>                 likely(!pic_in_kernel(vcpu->kvm));
>  }


Just judged superficially by the function names, it seems that the
logic is better to be put in kvm_cpu_accept_dm_intr() or some deeper
function nested in kvm_cpu_accept_dm_intr().

The function name will tell us that the interrupt is not injected
because the CPU doesn't accept it.  And it will also have an effect
that vcpu->run->ready_for_interrupt_injection will always be false
which I think is better to have for TDX.

>
> --
> 2.25.1
>