KVM: x86: Add support of clear Trace_ToPA_PMI status

Let guests clear the Intel PT ToPA PMI status (bit 55 of
MSR_CORE_PERF_GLOBAL_OVF_CTRL).
Signed-off-by: Luwei Kang <luwei.kang@intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

arch/x86/include/asm/kvm_host.h

@@ -469,6 +469,7 @@ struct kvm_pmu {
 	u64 global_ovf_ctrl;
 	u64 counter_bitmask[2];
 	u64 global_ctrl_mask;
+	u64 global_ovf_ctrl_mask;
 	u64 reserved_bits;
 	u8 version;
 	struct kvm_pmc gp_counters[INTEL_PMC_MAX_GENERIC];

arch/x86/include/asm/msr-index.h

@@ -784,6 +784,10 @@
 /* PERF_GLOBAL_OVF_CTL bits */
 #define MSR_CORE_PERF_GLOBAL_OVF_CTRL_TRACE_TOPA_PMI_BIT	55
 #define MSR_CORE_PERF_GLOBAL_OVF_CTRL_TRACE_TOPA_PMI		(1ULL << MSR_CORE_PERF_GLOBAL_OVF_CTRL_TRACE_TOPA_PMI_BIT)
+#define MSR_CORE_PERF_GLOBAL_OVF_CTRL_OVF_BUF_BIT		62
+#define MSR_CORE_PERF_GLOBAL_OVF_CTRL_OVF_BUF			(1ULL <<  MSR_CORE_PERF_GLOBAL_OVF_CTRL_OVF_BUF_BIT)
+#define MSR_CORE_PERF_GLOBAL_OVF_CTRL_COND_CHGD_BIT		63
+#define MSR_CORE_PERF_GLOBAL_OVF_CTRL_COND_CHGD			(1ULL << MSR_CORE_PERF_GLOBAL_OVF_CTRL_COND_CHGD_BIT)
 
 /* Geode defined MSRs */
 #define MSR_GEODE_BUSCONT_CONF0		0x00001900

arch/x86/kvm/vmx/pmu_intel.c

@@ -227,7 +227,7 @@ static int intel_pmu_set_msr(struct kvm_vcpu *vcpu, struct msr_data *msr_info)
 		}
 		break;
 	case MSR_CORE_PERF_GLOBAL_OVF_CTRL:
-		if (!(data & (pmu->global_ctrl_mask & ~(3ull<<62)))) {
+		if (!(data & pmu->global_ovf_ctrl_mask)) {
 			if (!msr_info->host_initiated)
 				pmu->global_status &= ~data;
 			pmu->global_ovf_ctrl = data;
@@ -297,6 +297,12 @@ static void intel_pmu_refresh(struct kvm_vcpu *vcpu)
 	pmu->global_ctrl = ((1ull << pmu->nr_arch_gp_counters) - 1) |
 		(((1ull << pmu->nr_arch_fixed_counters) - 1) << INTEL_PMC_IDX_FIXED);
 	pmu->global_ctrl_mask = ~pmu->global_ctrl;
+	pmu->global_ovf_ctrl_mask = pmu->global_ctrl_mask
+			& ~(MSR_CORE_PERF_GLOBAL_OVF_CTRL_OVF_BUF |
+			    MSR_CORE_PERF_GLOBAL_OVF_CTRL_COND_CHGD);
+	if (kvm_x86_ops->pt_supported())
+		pmu->global_ovf_ctrl_mask &=
+				~MSR_CORE_PERF_GLOBAL_OVF_CTRL_TRACE_TOPA_PMI;
 
 	entry = kvm_find_cpuid_entry(vcpu, 7, 0);
 	if (entry &&