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-rw-r--r--arch/arm64/include/asm/kvm_host.h2
-rw-r--r--arch/arm64/kvm/pmu-emul.c80
2 files changed, 77 insertions, 5 deletions
diff --git a/arch/arm64/include/asm/kvm_host.h b/arch/arm64/include/asm/kvm_host.h
index e52c927aade5..33e0f0a64c42 100644
--- a/arch/arm64/include/asm/kvm_host.h
+++ b/arch/arm64/include/asm/kvm_host.h
@@ -110,6 +110,8 @@ struct kvm_arch {
* supported.
*/
bool return_nisv_io_abort_to_user;
+
+ unsigned int pmuver;
};
struct kvm_vcpu_fault_info {
diff --git a/arch/arm64/kvm/pmu-emul.c b/arch/arm64/kvm/pmu-emul.c
index 363f188fb707..10d3860a9c0a 100644
--- a/arch/arm64/kvm/pmu-emul.c
+++ b/arch/arm64/kvm/pmu-emul.c
@@ -20,6 +20,21 @@ static void kvm_pmu_stop_counter(struct kvm_vcpu *vcpu, struct kvm_pmc *pmc);
#define PERF_ATTR_CFG1_KVM_PMU_CHAINED 0x1
+static u32 kvm_pmu_event_mask(struct kvm *kvm)
+{
+ switch (kvm->arch.pmuver) {
+ case 1: /* ARMv8.0 */
+ return GENMASK(9, 0);
+ case 4: /* ARMv8.1 */
+ case 5: /* ARMv8.4 */
+ case 6: /* ARMv8.5 */
+ return GENMASK(15, 0);
+ default: /* Shouldn't be here, just for sanity */
+ WARN_ONCE(1, "Unknown PMU version %d\n", kvm->arch.pmuver);
+ return 0;
+ }
+}
+
/**
* kvm_pmu_idx_is_64bit - determine if select_idx is a 64bit counter
* @vcpu: The vcpu pointer
@@ -100,7 +115,7 @@ static bool kvm_pmu_idx_has_chain_evtype(struct kvm_vcpu *vcpu, u64 select_idx)
return false;
reg = PMEVTYPER0_EL0 + select_idx;
- eventsel = __vcpu_sys_reg(vcpu, reg) & ARMV8_PMU_EVTYPE_EVENT;
+ eventsel = __vcpu_sys_reg(vcpu, reg) & kvm_pmu_event_mask(vcpu->kvm);
return eventsel == ARMV8_PMUV3_PERFCTR_CHAIN;
}
@@ -495,7 +510,7 @@ void kvm_pmu_software_increment(struct kvm_vcpu *vcpu, u64 val)
/* PMSWINC only applies to ... SW_INC! */
type = __vcpu_sys_reg(vcpu, PMEVTYPER0_EL0 + i);
- type &= ARMV8_PMU_EVTYPE_EVENT;
+ type &= kvm_pmu_event_mask(vcpu->kvm);
if (type != ARMV8_PMUV3_PERFCTR_SW_INCR)
continue;
@@ -578,7 +593,7 @@ static void kvm_pmu_create_perf_event(struct kvm_vcpu *vcpu, u64 select_idx)
data = __vcpu_sys_reg(vcpu, reg);
kvm_pmu_stop_counter(vcpu, pmc);
- eventsel = data & ARMV8_PMU_EVTYPE_EVENT;
+ eventsel = data & kvm_pmu_event_mask(vcpu->kvm);;
/* Software increment event does't need to be backed by a perf event */
if (eventsel == ARMV8_PMUV3_PERFCTR_SW_INCR &&
@@ -679,17 +694,66 @@ static void kvm_pmu_update_pmc_chained(struct kvm_vcpu *vcpu, u64 select_idx)
void kvm_pmu_set_counter_event_type(struct kvm_vcpu *vcpu, u64 data,
u64 select_idx)
{
- u64 reg, event_type = data & ARMV8_PMU_EVTYPE_MASK;
+ u64 reg, mask;
+
+ mask = ARMV8_PMU_EVTYPE_MASK;
+ mask &= ~ARMV8_PMU_EVTYPE_EVENT;
+ mask |= kvm_pmu_event_mask(vcpu->kvm);
reg = (select_idx == ARMV8_PMU_CYCLE_IDX)
? PMCCFILTR_EL0 : PMEVTYPER0_EL0 + select_idx;
- __vcpu_sys_reg(vcpu, reg) = event_type;
+ __vcpu_sys_reg(vcpu, reg) = data & mask;
kvm_pmu_update_pmc_chained(vcpu, select_idx);
kvm_pmu_create_perf_event(vcpu, select_idx);
}
+static int kvm_pmu_probe_pmuver(void)
+{
+ struct perf_event_attr attr = { };
+ struct perf_event *event;
+ struct arm_pmu *pmu;
+ int pmuver = 0xf;
+
+ /*
+ * Create a dummy event that only counts user cycles. As we'll never
+ * leave this function with the event being live, it will never
+ * count anything. But it allows us to probe some of the PMU
+ * details. Yes, this is terrible.
+ */
+ attr.type = PERF_TYPE_RAW;
+ attr.size = sizeof(attr);
+ attr.pinned = 1;
+ attr.disabled = 0;
+ attr.exclude_user = 0;
+ attr.exclude_kernel = 1;
+ attr.exclude_hv = 1;
+ attr.exclude_host = 1;
+ attr.config = ARMV8_PMUV3_PERFCTR_CPU_CYCLES;
+ attr.sample_period = GENMASK(63, 0);
+
+ event = perf_event_create_kernel_counter(&attr, -1, current,
+ kvm_pmu_perf_overflow, &attr);
+
+ if (IS_ERR(event)) {
+ pr_err_once("kvm: pmu event creation failed %ld\n",
+ PTR_ERR(event));
+ return 0xf;
+ }
+
+ if (event->pmu) {
+ pmu = to_arm_pmu(event->pmu);
+ if (pmu->pmuver)
+ pmuver = pmu->pmuver;
+ }
+
+ perf_event_disable(event);
+ perf_event_release_kernel(event);
+
+ return pmuver;
+}
+
bool kvm_arm_support_pmu_v3(void)
{
/*
@@ -794,6 +858,12 @@ int kvm_arm_pmu_v3_set_attr(struct kvm_vcpu *vcpu, struct kvm_device_attr *attr)
if (vcpu->arch.pmu.created)
return -EBUSY;
+ if (!vcpu->kvm->arch.pmuver)
+ vcpu->kvm->arch.pmuver = kvm_pmu_probe_pmuver();
+
+ if (vcpu->kvm->arch.pmuver == 0xf)
+ return -ENODEV;
+
switch (attr->attr) {
case KVM_ARM_VCPU_PMU_V3_IRQ: {
int __user *uaddr = (int __user *)(long)attr->addr;