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KVM: PMU emulation: GLOBAL_CTRL MSR should be enabled on reset.

PATCH In review Gleb Natapov 2 participants 2 messages Apr 9, 2012 – Apr 10, 2012

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Gleb Natapov

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#0 lore raw

PATCH 1/1 KVM: PMU emulation: GLOBAL_CTRL MSR should be enabled on reset.

On reset all MPU counters should be enabled in GLOBAL_CTRL MSR.

Signed-off-by Gleb Natapov <[email protected]>
arch/x86/kvm/pmu.c +9 -9
index 173df38..2e88438 100644
@@ -459,17 +459,17 @@ void kvm_pmu_cpuid_update(struct kvm_vcpu *vcpu)
 	pmu->available_event_types = ~entry->ebx & ((1ull << bitmap_len) - 1);
 
 	if (pmu->version == 1) {
-		pmu->global_ctrl = (1 << pmu->nr_arch_gp_counters) - 1;
-		return;
+		pmu->nr_arch_fixed_counters = 0;
+	} else {
+		pmu->nr_arch_fixed_counters = min((int)(entry->edx & 0x1f),
+				X86_PMC_MAX_FIXED);
+		pmu->counter_bitmask[KVM_PMC_FIXED] =
+			((u64)1 << ((entry->edx >> 5) & 0xff)) - 1;
 	}
 
-	pmu->nr_arch_fixed_counters = min((int)(entry->edx & 0x1f),
-			X86_PMC_MAX_FIXED);
-	pmu->counter_bitmask[KVM_PMC_FIXED] =
-		((u64)1 << ((entry->edx >> 5) & 0xff)) - 1;
-	pmu->global_ctrl_mask = ~(((1 << pmu->nr_arch_gp_counters) - 1)
-			| (((1ull << pmu->nr_arch_fixed_counters) - 1)
-				<< X86_PMC_IDX_FIXED));
+	pmu->global_ctrl = ((1 << pmu->nr_arch_gp_counters) - 1) |
+		(((1ull << pmu->nr_arch_fixed_counters) - 1) << X86_PMC_IDX_FIXED);
+	pmu->global_ctrl_mask = ~pmu->global_ctrl;
 }
 
 void kvm_pmu_init(struct kvm_vcpu *vcpu)

--
Gleb.

#1 lore raw
Quoted 24 lines · Gleb Natapov

On reset all MPU counters should be enabled in GLOBAL_CTRL MSR.

Signed-off-by Gleb Natapov <[email protected]>
arch/x86/kvm/pmu.c +6 -5
index 173df38..2e88438 100644
@@ -459,17 +459,17 @@ void kvm_pmu_cpuid_update(struct kvm_vcpu *vcpu)
 	pmu->available_event_types = ~entry->ebx & ((1ull << bitmap_len) - 1);
 
 	if (pmu->version == 1) {
-		pmu->global_ctrl = (1 << pmu->nr_arch_gp_counters) - 1;
-		return;
+		pmu->nr_arch_fixed_counters = 0;
+	} else {
+		pmu->nr_arch_fixed_counters = min((int)(entry->edx & 0x1f),
+				X86_PMC_MAX_FIXED);
+		pmu->counter_bitmask[KVM_PMC_FIXED] =
+			((u64)1 << ((entry->edx >> 5) & 0xff)) - 1;
 	}
 
-	pmu->nr_arch_fixed_counters = min((int)(entry->edx & 0x1f),
-			X86_PMC_MAX_FIXED);
-	pmu->counter_bitmask[KVM_PMC_FIXED] =

arch/x86/kvm/pmu.c void kvm_pmu_cpuid_update(struct kvm_vcpu *vcpu) · line 475

Quoted 10 lines
arch/x86/kvm/pmu.c +3 -4
-		((u64)1 << ((entry->edx >> 5) & 0xff)) - 1;
-	pmu->global_ctrl_mask = ~(((1 << pmu->nr_arch_gp_counters) - 1)
-			| (((1ull << pmu->nr_arch_fixed_counters) - 1)
-				<< X86_PMC_IDX_FIXED));
+	pmu->global_ctrl = ((1 << pmu->nr_arch_gp_counters) - 1) |
+		(((1ull << pmu->nr_arch_fixed_counters) - 1) << X86_PMC_IDX_FIXED);
+	pmu->global_ctrl_mask = ~pmu->global_ctrl;
 }

This is not called on INIT (not sure it should be). On the other hand update_cpuid() is not the best place to initialize stuff.

Oh well, this can be fixed later (not sure its possible), I'll apply this to master.

Signature · 1 line
error compiling committee.c: too many arguments to function