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

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Date:   Thu, 21 Dec 2017 12:51:01 +0100
From:   Paolo Bonzini <pbonzini@...hat.com>
To:     linux-kernel@...r.kernel.org, kvm@...r.kernel.org
Cc:     jmattson@...gle.com, david@...hat.com
Subject: [PATCH 2/3] KVM: vmx: simplify MSR bitmap setup

The APICv-enabled MSR bitmap passes through all MSRs in the
APICv-disabled bitmap (and then some).  Make that obvious in
vmx_disable_intercept_msr_x2apic.

Signed-off-by: Paolo Bonzini <pbonzini@...hat.com>
---
	v1->v2: included the right version of the patch

 arch/x86/kvm/vmx.c | 14 ++++++--------
 1 file changed, 6 insertions(+), 8 deletions(-)

diff --git a/arch/x86/kvm/vmx.c b/arch/x86/kvm/vmx.c
index 2b27afc93cb4..68239aabec52 100644
--- a/arch/x86/kvm/vmx.c
+++ b/arch/x86/kvm/vmx.c
@@ -5257,14 +5257,13 @@ static void pt_disable_intercept_for_msr(bool flag)
 	}
 }
 
-static void vmx_disable_intercept_msr_x2apic(u32 msr, int type, bool apicv_active)
+static void vmx_disable_intercept_msr_x2apic(u32 msr, int type, bool apicv_only)
 {
-	if (apicv_active) {
-		__vmx_disable_intercept_for_msr(vmx_msr_bitmap_legacy_x2apic_apicv,
-				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_apicv,
+					msr, type);
+	__vmx_disable_intercept_for_msr(vmx_msr_bitmap_longmode_x2apic_apicv,
+					msr, type);
+	if (!apicv_only) {
 		__vmx_disable_intercept_for_msr(vmx_msr_bitmap_legacy_x2apic,
 				msr, type);
 		__vmx_disable_intercept_for_msr(vmx_msr_bitmap_longmode_x2apic,
@@ -7149,7 +7148,6 @@ 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