[PATCH 19/23] KVM: x86/pmu: Always intercept GLOBAL_INUSE under PerfMon masking

[Zide Chen]

Unlike IA32_PERF_GLOBAL_CTRL, hardware does not filter GLOBAL_INUSE
reads based on the PerfMon mask at all, so always intercept this MSR
and filter out host-owned bits in KVM.

Signed-off-by: Zide Chen <zide.chen@xxxxxxxxx>
---
 arch/x86/kvm/vmx/vmx.c | 9 ++++++++-
 1 file changed, 8 insertions(+), 1 deletion(-)

diff --git a/arch/x86/kvm/vmx/vmx.c b/arch/x86/kvm/vmx/vmx.c
index a241efb99b3d..2bd1ffe65510 100644
--- a/arch/x86/kvm/vmx/vmx.c
+++ b/arch/x86/kvm/vmx/vmx.c
@@ -4339,8 +4339,15 @@ static void vmx_recalc_pmu_msr_intercepts(struct kvm_vcpu *vcpu)
 				  MSR_TYPE_RW, intercept);
 	vmx_set_intercept_for_msr(vcpu, MSR_CORE_PERF_GLOBAL_STATUS_SET,
 				  MSR_TYPE_RW, intercept || pmu->version < 4);
+
+	/*
+	 * IA32_PERF_GLOBAL_INUSE reads are not subject to PerfMon mask
+	 * filtering.
+	 */
 	vmx_set_intercept_for_msr(vcpu, MSR_CORE_PERF_GLOBAL_INUSE,
-				  MSR_TYPE_RW, intercept || pmu->version < 4);
+				  MSR_TYPE_RW,
+				  intercept || kvm_vcpu_has_perfmon_mask(vcpu) ||
+				  pmu->version < 4);
 
 	intercept = !has_mediated_pmu || !kvm_vcpu_has_perf_metrics(vcpu);
 	vmx_set_intercept_for_msr(vcpu, MSR_PERF_METRICS,
-- 
2.55.0