linux-kernel - [PATCH 2/3] KVM: vmx: simplify MSR bitmap setup

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Date:   Wed, 20 Dec 2017 13:05:37 +0100
From:   Paolo Bonzini <pbonzini@...hat.com>
To:     linux-kernel@...r.kernel.org, kvm@...r.kernel.org
Cc:     david@...hat.com, jmattson@...gle.com
Subject: [PATCH 2/3] KVM: vmx: simplify MSR bitmap setup

The APICv-enabled MSR bitmap is a superset of the APICv-disabled bitmap.
Make that obvious in vmx_disable_intercept_msr_x2apic.

Signed-off-by: Paolo Bonzini <pbonzini@...hat.com>
---
 arch/x86/kvm/vmx.c | 8 ++------
 1 file changed, 2 insertions(+), 6 deletions(-)

diff --git a/arch/x86/kvm/vmx.c b/arch/x86/kvm/vmx.c
index 9f9c3194440f..905aaa778306 100644
--- a/arch/x86/kvm/vmx.c
+++ b/arch/x86/kvm/vmx.c
@@ -5263,12 +5263,9 @@ static void vmx_disable_intercept_msr_x2apic(u32 msr, int type, bool apicv_activ
 				msr, type);
 		__vmx_disable_intercept_for_msr(vmx_msr_bitmap_longmode_x2apic_apicv,
 				msr, type);
-	} else {
-		__vmx_disable_intercept_for_msr(vmx_msr_bitmap_legacy_x2apic,
-				msr, type);
-		__vmx_disable_intercept_for_msr(vmx_msr_bitmap_longmode_x2apic,
-				msr, type);
 	}
+	__vmx_disable_intercept_for_msr(vmx_msr_bitmap_legacy_x2apic, msr, type);
+	__vmx_disable_intercept_for_msr(vmx_msr_bitmap_longmode_x2apic, msr, type);
 }
 
 static bool vmx_get_enable_apicv(struct kvm_vcpu *vcpu)
@@ -7148,7 +7145,6 @@ static __init int hardware_setup(void)
 	 * TPR reads and writes can be virtualized even if virtual interrupt
 	 * delivery is not in use.
 	 */
-	vmx_disable_intercept_msr_x2apic(0x808, MSR_TYPE_W, true);
 	vmx_disable_intercept_msr_x2apic(0x808, MSR_TYPE_R | MSR_TYPE_W, false);
 
 	/* EOI */
-- 
1.8.3.1