From: Sandipan Das <sandipan.das@xxxxxxx> Since passthrough PMU can be also used on some AMD platforms, set the "enable_passthrough_pmu" KVM kernel module parameter to true when the following conditions are met. - parameter is set to true when module loaded - enable_pmu is true - is running on and AMD CPU - CPU supports PerfMonV2 - host PMU supports passthrough mode Signed-off-by: Sandipan Das <sandipan.das@xxxxxxx> --- arch/x86/kvm/pmu.h | 20 ++++++++++++-------- arch/x86/kvm/svm/svm.c | 2 ++ 2 files changed, 14 insertions(+), 8 deletions(-) diff --git a/arch/x86/kvm/pmu.h b/arch/x86/kvm/pmu.h index 10553bc1ae1d..02ea90431033 100644 --- a/arch/x86/kvm/pmu.h +++ b/arch/x86/kvm/pmu.h @@ -196,6 +196,7 @@ extern struct kvm_pmu_emulated_event_selectors kvm_pmu_eventsel; static inline void kvm_init_pmu_capability(const struct kvm_pmu_ops *pmu_ops) { bool is_intel = boot_cpu_data.x86_vendor == X86_VENDOR_INTEL; + bool is_amd = boot_cpu_data.x86_vendor == X86_VENDOR_AMD; int min_nr_gp_ctrs = pmu_ops->MIN_NR_GP_COUNTERS; /* @@ -223,18 +224,21 @@ static inline void kvm_init_pmu_capability(const struct kvm_pmu_ops *pmu_ops) enable_pmu = false; } - /* Pass-through vPMU is only supported in Intel CPUs. */ - if (!is_intel) + /* Pass-through vPMU is only supported in Intel and AMD CPUs. */ + if (!is_intel && !is_amd) enable_passthrough_pmu = false; /* - * Pass-through vPMU requires at least PerfMon version 4 because the - * implementation requires the usage of MSR_CORE_PERF_GLOBAL_STATUS_SET - * for counter emulation as well as PMU context switch. In addition, it - * requires host PMU support on passthrough mode. Disable pass-through - * vPMU if any condition fails. + * On Intel platforms, pass-through vPMU requires at least PerfMon + * version 4 because the implementation requires the usage of + * MSR_CORE_PERF_GLOBAL_STATUS_SET for counter emulation as well as + * PMU context switch. In addition, it requires host PMU support on + * passthrough mode. Disable pass-through vPMU if any condition fails. + * + * On AMD platforms, pass-through vPMU requires at least PerfMonV2 + * because MSR_PERF_CNTR_GLOBAL_STATUS_SET is required. */ - if (!enable_pmu || kvm_pmu_cap.version < 4 || !kvm_pmu_cap.passthrough) + if (!enable_pmu || !kvm_pmu_cap.passthrough || (is_intel && kvm_pmu_cap.version < 4) || (is_amd && kvm_pmu_cap.version < 2)) enable_passthrough_pmu = false; if (!enable_pmu) { diff --git a/arch/x86/kvm/svm/svm.c b/arch/x86/kvm/svm/svm.c index d1a9f9951635..88648b3a9cdd 100644 --- a/arch/x86/kvm/svm/svm.c +++ b/arch/x86/kvm/svm/svm.c @@ -238,6 +238,8 @@ module_param(intercept_smi, bool, 0444); bool vnmi = true; module_param(vnmi, bool, 0444); +module_param(enable_passthrough_pmu, bool, 0444); + static bool svm_gp_erratum_intercept = true; static u8 rsm_ins_bytes[] = "\x0f\xaa"; -- 2.45.0.rc1.225.g2a3ae87e7f-goog