aboutsummaryrefslogtreecommitdiff
path: root/arch/x86/kvm/vmx
diff options
context:
space:
mode:
Diffstat (limited to 'arch/x86/kvm/vmx')
-rw-r--r--arch/x86/kvm/vmx/pmu_intel.c16
1 files changed, 14 insertions, 2 deletions
diff --git a/arch/x86/kvm/vmx/pmu_intel.c b/arch/x86/kvm/vmx/pmu_intel.c
index 1b1f888ad32b..03bd188b5754 100644
--- a/arch/x86/kvm/vmx/pmu_intel.c
+++ b/arch/x86/kvm/vmx/pmu_intel.c
@@ -20,6 +20,15 @@
#include "nested.h"
#include "pmu.h"
+/*
+ * Perf's "BASE" is wildly misleading, architectural PMUs use bits 31:16 of ECX
+ * to encode the "type" of counter to read, i.e. this is not a "base". And to
+ * further confuse things, non-architectural PMUs use bit 31 as a flag for
+ * "fast" reads, whereas the "type" is an explicit value.
+ */
+#define INTEL_RDPMC_FIXED INTEL_PMC_FIXED_RDPMC_BASE
+#define INTEL_RDPMC_FAST BIT(31)
+
#define MSR_PMC_FULL_WIDTH_BIT (MSR_IA32_PMC0 - MSR_IA32_PERFCTR0)
static void reprogram_fixed_counters(struct kvm_pmu *pmu, u64 data)
@@ -59,11 +68,14 @@ static struct kvm_pmc *intel_rdpmc_ecx_to_pmc(struct kvm_vcpu *vcpu,
unsigned int idx, u64 *mask)
{
struct kvm_pmu *pmu = vcpu_to_pmu(vcpu);
- bool fixed = idx & (1u << 30);
+ bool fixed = idx & INTEL_RDPMC_FIXED;
struct kvm_pmc *counters;
unsigned int num_counters;
- idx &= ~(3u << 30);
+ if (idx & INTEL_RDPMC_FAST)
+ *mask &= GENMASK_ULL(31, 0);
+
+ idx &= ~(INTEL_RDPMC_FIXED | INTEL_RDPMC_FAST);
if (fixed) {
counters = pmu->fixed_counters;
num_counters = pmu->nr_arch_fixed_counters;