linux-kernel - [PATCH] KVM: nVMX: remove unnecessary vmwrite from L2->L1 vmexit

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Date:   Mon,  1 Jan 2018 23:58:15 +0100
From:   Paolo Bonzini <pbonzini@...hat.com>
To:     linux-kernel@...r.kernel.org, kvm@...r.kernel.org
Cc:     jmattson@...gle.com
Subject: [PATCH] KVM: nVMX: remove unnecessary vmwrite from L2->L1 vmexit

The POSTED_INTR_NV field is constant (though it differs between the vmcs01 and
vmcs02), there is no need to reload it on vmexit to L1.

Signed-off-by: Paolo Bonzini <pbonzini@...hat.com>
---
 arch/x86/kvm/vmx.c | 3 ---
 1 file changed, 3 deletions(-)

diff --git a/arch/x86/kvm/vmx.c b/arch/x86/kvm/vmx.c
index e6223fe8faa1..1e184830a295 100644
--- a/arch/x86/kvm/vmx.c
+++ b/arch/x86/kvm/vmx.c
@@ -11610,9 +11610,6 @@ static void load_vmcs12_host_state(struct kvm_vcpu *vcpu,
 		 */
 		vmx_flush_tlb(vcpu, true);
 	}
-	/* Restore posted intr vector. */
-	if (nested_cpu_has_posted_intr(vmcs12))
-		vmcs_write16(POSTED_INTR_NV, POSTED_INTR_VECTOR);
 
 	vmcs_write32(GUEST_SYSENTER_CS, vmcs12->host_ia32_sysenter_cs);
 	vmcs_writel(GUEST_SYSENTER_ESP, vmcs12->host_ia32_sysenter_esp);
-- 
1.8.3.1