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Diffstat (limited to 'arch/x86/kvm/pmu.c')
-rw-r--r--arch/x86/kvm/pmu.c16
1 files changed, 14 insertions, 2 deletions
diff --git a/arch/x86/kvm/pmu.c b/arch/x86/kvm/pmu.c
index c397b28e3d1b..a593b03c9aed 100644
--- a/arch/x86/kvm/pmu.c
+++ b/arch/x86/kvm/pmu.c
@@ -775,8 +775,20 @@ void kvm_pmu_refresh(struct kvm_vcpu *vcpu)
pmu->pebs_data_cfg_mask = ~0ull;
bitmap_zero(pmu->all_valid_pmc_idx, X86_PMC_IDX_MAX);
- if (vcpu->kvm->arch.enable_pmu)
- static_call(kvm_x86_pmu_refresh)(vcpu);
+ if (!vcpu->kvm->arch.enable_pmu)
+ return;
+
+ static_call(kvm_x86_pmu_refresh)(vcpu);
+
+ /*
+ * At RESET, both Intel and AMD CPUs set all enable bits for general
+ * purpose counters in IA32_PERF_GLOBAL_CTRL (so that software that
+ * was written for v1 PMUs don't unknowingly leave GP counters disabled
+ * in the global controls). Emulate that behavior when refreshing the
+ * PMU so that userspace doesn't need to manually set PERF_GLOBAL_CTRL.
+ */
+ if (kvm_pmu_has_perf_global_ctrl(pmu) && pmu->nr_arch_gp_counters)
+ pmu->global_ctrl = GENMASK_ULL(pmu->nr_arch_gp_counters - 1, 0);
}
void kvm_pmu_init(struct kvm_vcpu *vcpu)