diff options
| author | Like Xu <likexu@tencent.com> | 2022-06-01 06:19:24 +0300 |
|---|---|---|
| committer | Paolo Bonzini <pbonzini@redhat.com> | 2022-06-08 20:06:17 +0300 |
| commit | 6ef25aa0a961298278301ae1d88106c701eb73fa (patch) | |
| tree | bd57de8db47e08927d016a4153d9f707a09dfe76 /arch/x86/kvm/vmx/capabilities.h | |
| parent | b9181c8ef35636152facc72f801f27b4264df8c0 (diff) | |
| download | linux-6ef25aa0a961298278301ae1d88106c701eb73fa.tar.xz | |
KVM: x86/pmu: Restrict advanced features based on module enable_pmu
Once vPMU is disabled, the KVM would not expose features like:
PEBS (via clear kvm_pmu_cap.pebs_ept), legacy LBR and ARCH_LBR,
CPUID 0xA leaf, PDCM bit and MSR_IA32_PERF_CAPABILITIES, plus
PT_MODE_HOST_GUEST mode.
What this group of features has in common is that their use
relies on the underlying PMU counter and the host perf_event as a
back-end resource requester or sharing part of the irq delivery path.
Signed-off-by: Like Xu <likexu@tencent.com>
Message-Id: <20220601031925.59693-2-likexu@tencent.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Diffstat (limited to 'arch/x86/kvm/vmx/capabilities.h')
| -rw-r--r-- | arch/x86/kvm/vmx/capabilities.h | 4 |
1 files changed, 4 insertions, 0 deletions
diff --git a/arch/x86/kvm/vmx/capabilities.h b/arch/x86/kvm/vmx/capabilities.h index 2d3f13b18714..292e58679d95 100644 --- a/arch/x86/kvm/vmx/capabilities.h +++ b/arch/x86/kvm/vmx/capabilities.h @@ -7,6 +7,7 @@ #include "lapic.h" #include "x86.h" #include "pmu.h" +#include "cpuid.h" extern bool __read_mostly enable_vpid; extern bool __read_mostly flexpriority_enabled; @@ -409,6 +410,9 @@ static inline u64 vmx_get_perf_capabilities(void) u64 perf_cap = PMU_CAP_FW_WRITES; u64 host_perf_cap = 0; + if (!enable_pmu) + return 0; + if (boot_cpu_has(X86_FEATURE_PDCM)) rdmsrl(MSR_IA32_PERF_CAPABILITIES, host_perf_cap); |