KVM: x86: Fix APIC map calculation after re-enabling

PATCH Applied Jan Kiszka 2 participants 2 messages Dec 29, 2013 – Dec 30, 2013

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x86 KVM KVM x86

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Jan Kiszka

author

2013-12-29 01:29 UTC #0 lore raw

PATCH 1/1 KVM: x86: Fix APIC map calculation after re-enabling

From: Jan Kiszka <[email protected]>

Update arch.apic_base before triggering recalculate_apic_map. Otherwise the recalculation will work against the previous state of the APIC and will fail to build the correct map when an APIC is hardware-enabled again.

This fixes a regression of 1e08ec4a13.

Signed-off-by Jan Kiszka <[email protected]>

---

Stable material.

 arch/x86/kvm/lapic.c | 8 ++++----
 1 file changed, 4 insertions(+), 4 deletions(-)

arch/x86/kvm/lapic.c +4 -4

index 5439117..ab58ea4 100644
@@ -1346,6 +1346,10 @@ void kvm_lapic_set_base(struct kvm_vcpu *vcpu, u64 value)
 		return;
 	}
 
+	if (!kvm_vcpu_is_bsp(apic->vcpu))
+		value &= ~MSR_IA32_APICBASE_BSP;
+	vcpu->arch.apic_base = value;
+
 	/* update jump label if enable bit changes */
 	if ((vcpu->arch.apic_base ^ value) & MSR_IA32_APICBASE_ENABLE) {
 		if (value & MSR_IA32_APICBASE_ENABLE)

@@ -1355,10 +1359,6 @@ void kvm_lapic_set_base(struct kvm_vcpu *vcpu, u64 value)
 		recalculate_apic_map(vcpu->kvm);
 	}
 
-	if (!kvm_vcpu_is_bsp(apic->vcpu))
-		value &= ~MSR_IA32_APICBASE_BSP;
-
-	vcpu->arch.apic_base = value;
 	if ((old_value ^ value) & X2APIC_ENABLE) {
 		if (value & X2APIC_ENABLE) {
 			u32 id = kvm_apic_id(apic);

Signature · 1 line

1.8.1.1.298.ge7eed54

Marcelo Tosatti

Applied

2013-12-30 20:59 UTC #1 lore raw

Quoted 34 lines · Jan Kiszka

From: Jan Kiszka <[email protected]>
Update arch.apic_base before triggering recalculate_apic_map. Otherwise the recalculation will work against the previous state of the APIC and will fail to build the correct map when an APIC is hardware-enabled again.
This fixes a regression of 1e08ec4a13.
Signed-off-by Jan Kiszka <[email protected]>
---
Stable material.
 arch/x86/kvm/lapic.c | 8 ++++----
 1 file changed, 4 insertions(+), 4 deletions(-)
arch/x86/kvm/lapic.c +4 -0
index 5439117..ab58ea4 100644
@@ -1346,6 +1346,10 @@ void kvm_lapic_set_base(struct kvm_vcpu *vcpu, u64 value)
 		return;
 	}
 
+	if (!kvm_vcpu_is_bsp(apic->vcpu))
+		value &= ~MSR_IA32_APICBASE_BSP;
+	vcpu->arch.apic_base = value;
+
 	/* update jump label if enable bit changes */
 	if ((vcpu->arch.apic_base ^ value) & MSR_IA32_APICBASE_ENABLE) {
 		if (value & MSR_IA32_APICBASE_ENABLE)

arch/x86/kvm/lapic.c void kvm_lapic_set_base(struct kvm_vcpu *vcpu, u64 value) · line 1364

Quoted 10 lines

arch/x86/kvm/lapic.c +0 -4

@@ -1355,10 +1359,6 @@ void kvm_lapic_set_base(struct kvm_vcpu *vcpu, u64 value)
 		recalculate_apic_map(vcpu->kvm);
 	}
 
-	if (!kvm_vcpu_is_bsp(apic->vcpu))
-		value &= ~MSR_IA32_APICBASE_BSP;
-
-	vcpu->arch.apic_base = value;
 	if ((old_value ^ value) & X2APIC_ENABLE) {
 		if (value & X2APIC_ENABLE) {
 			u32 id = kvm_apic_id(apic);

Applied to master branch, thanks.