This is a note to let you know that I've just added the patch titled
KVM: x86: Track supported PERF_CAPABILITIES in kvm_caps
to the 6.1-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
The filename of the patch is:
kvm-x86-track-supported-perf_capabilities-in-kvm_cap.patch
and it can be found in the queue-6.1 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
commit 231fd45b949ebb4460a53a7f252ab462c02600b5
Author: Sean Christopherson <seanjc@xxxxxxxxxx>
Date: Thu Oct 6 00:03:11 2022 +0000
KVM: x86: Track supported PERF_CAPABILITIES in kvm_caps
[ Upstream commit bec46859fb9d797a21c983100b1f425bebe89747 ]
Track KVM's supported PERF_CAPABILITIES in kvm_caps instead of computing
the supported capabilities on the fly every time. Using kvm_caps will
also allow for future cleanups as the kvm_caps values can be used
directly in common x86 code.
Signed-off-by: Sean Christopherson <seanjc@xxxxxxxxxx>
Acked-by: Like Xu <likexu@xxxxxxxxxxx>
Message-Id: <20221006000314.73240-6-seanjc@xxxxxxxxxx>
Signed-off-by: Paolo Bonzini <pbonzini@xxxxxxxxxx>
Stable-dep-of: 098f4c061ea1 ("KVM: x86/pmu: Disallow legacy LBRs if architectural LBRs are available")
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
diff --git a/arch/x86/kvm/svm/svm.c b/arch/x86/kvm/svm/svm.c
index 9599931c7d572..fc1649b5931a4 100644
--- a/arch/x86/kvm/svm/svm.c
+++ b/arch/x86/kvm/svm/svm.c
@@ -2709,6 +2709,7 @@ static int svm_get_msr_feature(struct kvm_msr_entry *msr)
msr->data |= MSR_AMD64_DE_CFG_LFENCE_SERIALIZE;
break;
case MSR_IA32_PERF_CAPABILITIES:
+ msr->data = kvm_caps.supported_perf_cap;
return 0;
default:
return KVM_MSR_RET_INVALID;
@@ -4888,6 +4889,7 @@ static __init void svm_set_cpu_caps(void)
{
kvm_set_cpu_caps();
+ kvm_caps.supported_perf_cap = 0;
kvm_caps.supported_xss = 0;
/* CPUID 0x80000001 and 0x8000000A (SVM features) */
diff --git a/arch/x86/kvm/vmx/capabilities.h b/arch/x86/kvm/vmx/capabilities.h
index 479124e49bbda..cd2ac9536c998 100644
--- a/arch/x86/kvm/vmx/capabilities.h
+++ b/arch/x86/kvm/vmx/capabilities.h
@@ -395,31 +395,6 @@ static inline bool vmx_pebs_supported(void)
return boot_cpu_has(X86_FEATURE_PEBS) && kvm_pmu_cap.pebs_ept;
}
-static inline u64 vmx_get_perf_capabilities(void)
-{
- u64 perf_cap = PMU_CAP_FW_WRITES;
- struct x86_pmu_lbr lbr;
- 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);
-
- x86_perf_get_lbr(&lbr);
- if (lbr.nr)
- perf_cap |= host_perf_cap & PMU_CAP_LBR_FMT;
-
- if (vmx_pebs_supported()) {
- perf_cap |= host_perf_cap & PERF_CAP_PEBS_MASK;
- if ((perf_cap & PERF_CAP_PEBS_FORMAT) < 4)
- perf_cap &= ~PERF_CAP_PEBS_BASELINE;
- }
-
- return perf_cap;
-}
-
static inline bool cpu_has_notify_vmexit(void)
{
return vmcs_config.cpu_based_2nd_exec_ctrl &
diff --git a/arch/x86/kvm/vmx/pmu_intel.c b/arch/x86/kvm/vmx/pmu_intel.c
index 10b33da9bd058..9fabfe71fd879 100644
--- a/arch/x86/kvm/vmx/pmu_intel.c
+++ b/arch/x86/kvm/vmx/pmu_intel.c
@@ -631,7 +631,7 @@ static void intel_pmu_init(struct kvm_vcpu *vcpu)
pmu->fixed_counters[i].current_config = 0;
}
- vcpu->arch.perf_capabilities = vmx_get_perf_capabilities();
+ vcpu->arch.perf_capabilities = kvm_caps.supported_perf_cap;
lbr_desc->records.nr = 0;
lbr_desc->event = NULL;
lbr_desc->msr_passthrough = false;
diff --git a/arch/x86/kvm/vmx/vmx.c b/arch/x86/kvm/vmx/vmx.c
index 4c9116d223df5..8ad5992f61340 100644
--- a/arch/x86/kvm/vmx/vmx.c
+++ b/arch/x86/kvm/vmx/vmx.c
@@ -1879,7 +1879,7 @@ static int vmx_get_msr_feature(struct kvm_msr_entry *msr)
return 1;
return vmx_get_vmx_msr(&vmcs_config.nested, msr->index, &msr->data);
case MSR_IA32_PERF_CAPABILITIES:
- msr->data = vmx_get_perf_capabilities();
+ msr->data = kvm_caps.supported_perf_cap;
return 0;
default:
return KVM_MSR_RET_INVALID;
@@ -2058,7 +2058,7 @@ static u64 vmx_get_supported_debugctl(struct kvm_vcpu *vcpu, bool host_initiated
(host_initiated || guest_cpuid_has(vcpu, X86_FEATURE_BUS_LOCK_DETECT)))
debugctl |= DEBUGCTLMSR_BUS_LOCK_DETECT;
- if ((vmx_get_perf_capabilities() & PMU_CAP_LBR_FMT) &&
+ if ((kvm_caps.supported_perf_cap & PMU_CAP_LBR_FMT) &&
(host_initiated || intel_pmu_lbr_is_enabled(vcpu)))
debugctl |= DEBUGCTLMSR_LBR | DEBUGCTLMSR_FREEZE_LBRS_ON_PMI;
@@ -2371,14 +2371,14 @@ static int vmx_set_msr(struct kvm_vcpu *vcpu, struct msr_data *msr_info)
return 1;
if (data & PMU_CAP_LBR_FMT) {
if ((data & PMU_CAP_LBR_FMT) !=
- (vmx_get_perf_capabilities() & PMU_CAP_LBR_FMT))
+ (kvm_caps.supported_perf_cap & PMU_CAP_LBR_FMT))
return 1;
if (!cpuid_model_is_consistent(vcpu))
return 1;
}
if (data & PERF_CAP_PEBS_FORMAT) {
if ((data & PERF_CAP_PEBS_MASK) !=
- (vmx_get_perf_capabilities() & PERF_CAP_PEBS_MASK))
+ (kvm_caps.supported_perf_cap & PERF_CAP_PEBS_MASK))
return 1;
if (!guest_cpuid_has(vcpu, X86_FEATURE_DS))
return 1;
@@ -7702,6 +7702,31 @@ static void vmx_vcpu_after_set_cpuid(struct kvm_vcpu *vcpu)
vmx_update_exception_bitmap(vcpu);
}
+static u64 vmx_get_perf_capabilities(void)
+{
+ u64 perf_cap = PMU_CAP_FW_WRITES;
+ struct x86_pmu_lbr lbr;
+ 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);
+
+ x86_perf_get_lbr(&lbr);
+ if (lbr.nr)
+ perf_cap |= host_perf_cap & PMU_CAP_LBR_FMT;
+
+ if (vmx_pebs_supported()) {
+ perf_cap |= host_perf_cap & PERF_CAP_PEBS_MASK;
+ if ((perf_cap & PERF_CAP_PEBS_FORMAT) < 4)
+ perf_cap &= ~PERF_CAP_PEBS_BASELINE;
+ }
+
+ return perf_cap;
+}
+
static __init void vmx_set_cpu_caps(void)
{
kvm_set_cpu_caps();
@@ -7724,6 +7749,7 @@ static __init void vmx_set_cpu_caps(void)
if (!enable_pmu)
kvm_cpu_cap_clear(X86_FEATURE_PDCM);
+ kvm_caps.supported_perf_cap = vmx_get_perf_capabilities();
if (!enable_sgx) {
kvm_cpu_cap_clear(X86_FEATURE_SGX);
diff --git a/arch/x86/kvm/x86.h b/arch/x86/kvm/x86.h
index 829d3134c1eb0..9de72586f4065 100644
--- a/arch/x86/kvm/x86.h
+++ b/arch/x86/kvm/x86.h
@@ -27,6 +27,7 @@ struct kvm_caps {
u64 supported_mce_cap;
u64 supported_xcr0;
u64 supported_xss;
+ u64 supported_perf_cap;
};
void kvm_spurious_fault(void);
