Received-SPF: pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 23.128.96.18 as permitted sender) client-ip=23.128.96.18;
From:   Zhenzhong Duan <zhenzhong.duan@gmail.com>
To:     linux-kernel@vger.kernel.org,
        virtualization@lists.linux-foundation.org, kvm@vger.kernel.org
Cc:     netdev@vger.kernel.org, pbonzini@redhat.com,
        sean.j.christopherson@intel.com, vkuznets@redhat.com,
        wanpengli@tencent.com, jmattson@google.com, joro@8bytes.org,
        tglx@linutronix.de, mingo@redhat.com, bp@alien8.de, mst@redhat.com,
        jasowang@redhat.com, Zhenzhong Duan <zhenzhong.duan@gmail.com>
Subject: [PATCH 2/2] KVM: not link irqfd with a fake IRQ bypass producer
Date:   Mon, 19 Oct 2020 17:06:57 +0800
Message-Id: <20201019090657.131-2-zhenzhong.duan@gmail.com>
In-Reply-To: <20201019090657.131-1-zhenzhong.duan@gmail.com>
References: <20201019090657.131-1-zhenzhong.duan@gmail.com>
MIME-Version: 1.0
Content-Transfer-Encoding: 8bit
Precedence: bulk

In case failure to setup Post interrupt for an IRQ, it make no sense
to assign irqfd->producer to the producer.

This change makes code more robust.

Signed-off-by: Zhenzhong Duan <zhenzhong.duan@gmail.com>
---
 arch/x86/kvm/x86.c | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c
index ce856e0..277e961 100644
--- a/arch/x86/kvm/x86.c
+++ b/arch/x86/kvm/x86.c
@@ -10683,13 +10683,14 @@ int kvm_arch_irq_bypass_add_producer(struct irq_bypass_consumer *cons,
 		container_of(cons, struct kvm_kernel_irqfd, consumer);
 	int ret;
 
-	irqfd->producer = prod;
 	kvm_arch_start_assignment(irqfd->kvm);
 	ret = kvm_x86_ops.update_pi_irte(irqfd->kvm,
 					 prod->irq, irqfd->gsi, 1);
 
 	if (ret)
 		kvm_arch_end_assignment(irqfd->kvm);
+	else
+		irqfd->producer = prod;
 
 	return ret;
 }
-- 
1.8.3.1