On 8/3/2022 9:24 am, Jim Mattson wrote:
The third nybble of AMD's event select overlaps with Intel's IN_TX and
IN_TXCP bits. Therefore, we can't use AMD64_RAW_EVENT_MASK on Intel
platforms that support TSX.
We already have pmu->reserved_bits as the first wall to check "can't use".
Declare a raw_event_mask in the kvm_pmu structure, initialize it in
the vendor-specific pmu_refresh() functions, and use that mask for
PERF_TYPE_RAW configurations in reprogram_gp_counter().
Fixes: 710c47651431 ("KVM: x86/pmu: Use AMD64_RAW_EVENT_MASK for PERF_TYPE_RAW")
Is it really a fix ?
Signed-off-by: Jim Mattson <jmattson@xxxxxxxxxx>
---
arch/x86/include/asm/kvm_host.h | 1 +
arch/x86/kvm/pmu.c | 3 ++-
arch/x86/kvm/svm/pmu.c | 1 +
arch/x86/kvm/vmx/pmu_intel.c | 1 +
4 files changed, 5 insertions(+), 1 deletion(-)
diff --git a/arch/x86/include/asm/kvm_host.h b/arch/x86/include/asm/kvm_host.h
index c45ab8b5c37f..cacd27c1aa19 100644
--- a/arch/x86/include/asm/kvm_host.h
+++ b/arch/x86/include/asm/kvm_host.h
@@ -510,6 +510,7 @@ struct kvm_pmu {
u64 global_ctrl_mask;
u64 global_ovf_ctrl_mask;
u64 reserved_bits;
+ u64 raw_event_mask;
u8 version;
struct kvm_pmc gp_counters[INTEL_PMC_MAX_GENERIC];
struct kvm_pmc fixed_counters[INTEL_PMC_MAX_FIXED];
diff --git a/arch/x86/kvm/pmu.c b/arch/x86/kvm/pmu.c
index b1a02993782b..902b6d700215 100644
--- a/arch/x86/kvm/pmu.c
+++ b/arch/x86/kvm/pmu.c
@@ -185,6 +185,7 @@ void reprogram_gp_counter(struct kvm_pmc *pmc, u64 eventsel)
u32 type = PERF_TYPE_RAW;
struct kvm *kvm = pmc->vcpu->kvm;
struct kvm_pmu_event_filter *filter;
+ struct kvm_pmu *pmu = vcpu_to_pmu(pmc->vcpu);
How about pmc_to_pmu(pmc) ?
bool allow_event = true;
if (eventsel & ARCH_PERFMON_EVENTSEL_PIN_CONTROL)
@@ -221,7 +222,7 @@ void reprogram_gp_counter(struct kvm_pmc *pmc, u64 eventsel)
}
if (type == PERF_TYPE_RAW)
- config = eventsel & AMD64_RAW_EVENT_MASK;
+ config = eventsel & pmu->raw_event_mask;
If the code base is current kvm/queue,
the checks about (eventsel & HSW_IN_TX*) is still there.
Not sure why we're wasting extra 'u64' space for nothing.
if (pmc->current_config == eventsel && pmc_resume_counter(pmc))
return;
diff --git a/arch/x86/kvm/svm/pmu.c b/arch/x86/kvm/svm/pmu.c
index 886e8ac5cfaa..24eb935b6f85 100644
--- a/arch/x86/kvm/svm/pmu.c
+++ b/arch/x86/kvm/svm/pmu.c
@@ -282,6 +282,7 @@ static void amd_pmu_refresh(struct kvm_vcpu *vcpu)
pmu->counter_bitmask[KVM_PMC_GP] = ((u64)1 << 48) - 1;
pmu->reserved_bits = 0xfffffff000280000ull;
+ pmu->raw_event_mask = AMD64_RAW_EVENT_MASK;
pmu->version = 1;
/* not applicable to AMD; but clean them to prevent any fall out */
pmu->counter_bitmask[KVM_PMC_FIXED] = 0;
diff --git a/arch/x86/kvm/vmx/pmu_intel.c b/arch/x86/kvm/vmx/pmu_intel.c
index 4e5b1eeeb77c..da71160a50d6 100644
--- a/arch/x86/kvm/vmx/pmu_intel.c
+++ b/arch/x86/kvm/vmx/pmu_intel.c
@@ -485,6 +485,7 @@ static void intel_pmu_refresh(struct kvm_vcpu *vcpu)
pmu->counter_bitmask[KVM_PMC_FIXED] = 0;
pmu->version = 0;
pmu->reserved_bits = 0xffffffff00200000ull;
+ pmu->raw_event_mask = X86_RAW_EVENT_MASK;
entry = kvm_find_cpuid_entry(vcpu, 0xa, 0);
if (!entry || !vcpu->kvm->arch.enable_pmu)
