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-rw-r--r--arch/arm64/include/asm/kvm_host.h5
-rw-r--r--arch/arm64/include/uapi/asm/kvm.h16
-rw-r--r--arch/arm64/kvm/arm.c2
-rw-r--r--arch/arm64/kvm/pmu-emul.c69
4 files changed, 86 insertions, 6 deletions
diff --git a/arch/arm64/include/asm/kvm_host.h b/arch/arm64/include/asm/kvm_host.h
index 33e0f0a64c42..0384defc2a01 100644
--- a/arch/arm64/include/asm/kvm_host.h
+++ b/arch/arm64/include/asm/kvm_host.h
@@ -111,6 +111,11 @@ struct kvm_arch {
*/
bool return_nisv_io_abort_to_user;
+ /*
+ * VM-wide PMU filter, implemented as a bitmap and big enough for
+ * up to 2^10 events (ARMv8.0) or 2^16 events (ARMv8.1+).
+ */
+ unsigned long *pmu_filter;
unsigned int pmuver;
};
diff --git a/arch/arm64/include/uapi/asm/kvm.h b/arch/arm64/include/uapi/asm/kvm.h
index ba85bb23f060..7b1511d6ce44 100644
--- a/arch/arm64/include/uapi/asm/kvm.h
+++ b/arch/arm64/include/uapi/asm/kvm.h
@@ -159,6 +159,21 @@ struct kvm_sync_regs {
struct kvm_arch_memory_slot {
};
+/*
+ * PMU filter structure. Describe a range of events with a particular
+ * action. To be used with KVM_ARM_VCPU_PMU_V3_FILTER.
+ */
+struct kvm_pmu_event_filter {
+ __u16 base_event;
+ __u16 nevents;
+
+#define KVM_PMU_EVENT_ALLOW 0
+#define KVM_PMU_EVENT_DENY 1
+
+ __u8 action;
+ __u8 pad[3];
+};
+
/* for KVM_GET/SET_VCPU_EVENTS */
struct kvm_vcpu_events {
struct {
@@ -329,6 +344,7 @@ struct kvm_vcpu_events {
#define KVM_ARM_VCPU_PMU_V3_CTRL 0
#define KVM_ARM_VCPU_PMU_V3_IRQ 0
#define KVM_ARM_VCPU_PMU_V3_INIT 1
+#define KVM_ARM_VCPU_PMU_V3_FILTER 2
#define KVM_ARM_VCPU_TIMER_CTRL 1
#define KVM_ARM_VCPU_TIMER_IRQ_VTIMER 0
#define KVM_ARM_VCPU_TIMER_IRQ_PTIMER 1
diff --git a/arch/arm64/kvm/arm.c b/arch/arm64/kvm/arm.c
index 46dc3d75cf13..427848ff6f20 100644
--- a/arch/arm64/kvm/arm.c
+++ b/arch/arm64/kvm/arm.c
@@ -145,6 +145,8 @@ void kvm_arch_destroy_vm(struct kvm *kvm)
{
int i;
+ bitmap_free(kvm->arch.pmu_filter);
+
kvm_vgic_destroy(kvm);
for (i = 0; i < KVM_MAX_VCPUS; ++i) {
diff --git a/arch/arm64/kvm/pmu-emul.c b/arch/arm64/kvm/pmu-emul.c
index 10d3860a9c0a..8cd365968af1 100644
--- a/arch/arm64/kvm/pmu-emul.c
+++ b/arch/arm64/kvm/pmu-emul.c
@@ -593,11 +593,21 @@ 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 & kvm_pmu_event_mask(vcpu->kvm);;
+ if (pmc->idx == ARMV8_PMU_CYCLE_IDX)
+ eventsel = ARMV8_PMUV3_PERFCTR_CPU_CYCLES;
+ else
+ eventsel = data & kvm_pmu_event_mask(vcpu->kvm);
+
+ /* Software increment event doesn't need to be backed by a perf event */
+ if (eventsel == ARMV8_PMUV3_PERFCTR_SW_INCR)
+ return;
- /* Software increment event does't need to be backed by a perf event */
- if (eventsel == ARMV8_PMUV3_PERFCTR_SW_INCR &&
- pmc->idx != ARMV8_PMU_CYCLE_IDX)
+ /*
+ * If we have a filter in place and that the event isn't allowed, do
+ * not install a perf event either.
+ */
+ if (vcpu->kvm->arch.pmu_filter &&
+ !test_bit(eventsel, vcpu->kvm->arch.pmu_filter))
return;
memset(&attr, 0, sizeof(struct perf_event_attr));
@@ -609,8 +619,7 @@ static void kvm_pmu_create_perf_event(struct kvm_vcpu *vcpu, u64 select_idx)
attr.exclude_kernel = data & ARMV8_PMU_EXCLUDE_EL1 ? 1 : 0;
attr.exclude_hv = 1; /* Don't count EL2 events */
attr.exclude_host = 1; /* Don't count host events */
- attr.config = (pmc->idx == ARMV8_PMU_CYCLE_IDX) ?
- ARMV8_PMUV3_PERFCTR_CPU_CYCLES : eventsel;
+ attr.config = eventsel;
counter = kvm_pmu_get_pair_counter_value(vcpu, pmc);
@@ -889,6 +898,53 @@ int kvm_arm_pmu_v3_set_attr(struct kvm_vcpu *vcpu, struct kvm_device_attr *attr)
vcpu->arch.pmu.irq_num = irq;
return 0;
}
+ case KVM_ARM_VCPU_PMU_V3_FILTER: {
+ struct kvm_pmu_event_filter __user *uaddr;
+ struct kvm_pmu_event_filter filter;
+ int nr_events;
+
+ nr_events = kvm_pmu_event_mask(vcpu->kvm) + 1;
+
+ uaddr = (struct kvm_pmu_event_filter __user *)(long)attr->addr;
+
+ if (copy_from_user(&filter, uaddr, sizeof(filter)))
+ return -EFAULT;
+
+ if (((u32)filter.base_event + filter.nevents) > nr_events ||
+ (filter.action != KVM_PMU_EVENT_ALLOW &&
+ filter.action != KVM_PMU_EVENT_DENY))
+ return -EINVAL;
+
+ mutex_lock(&vcpu->kvm->lock);
+
+ if (!vcpu->kvm->arch.pmu_filter) {
+ vcpu->kvm->arch.pmu_filter = bitmap_alloc(nr_events, GFP_KERNEL);
+ if (!vcpu->kvm->arch.pmu_filter) {
+ mutex_unlock(&vcpu->kvm->lock);
+ return -ENOMEM;
+ }
+
+ /*
+ * The default depends on the first applied filter.
+ * If it allows events, the default is to deny.
+ * Conversely, if the first filter denies a set of
+ * events, the default is to allow.
+ */
+ if (filter.action == KVM_PMU_EVENT_ALLOW)
+ bitmap_zero(vcpu->kvm->arch.pmu_filter, nr_events);
+ else
+ bitmap_fill(vcpu->kvm->arch.pmu_filter, nr_events);
+ }
+
+ if (filter.action == KVM_PMU_EVENT_ALLOW)
+ bitmap_set(vcpu->kvm->arch.pmu_filter, filter.base_event, filter.nevents);
+ else
+ bitmap_clear(vcpu->kvm->arch.pmu_filter, filter.base_event, filter.nevents);
+
+ mutex_unlock(&vcpu->kvm->lock);
+
+ return 0;
+ }
case KVM_ARM_VCPU_PMU_V3_INIT:
return kvm_arm_pmu_v3_init(vcpu);
}
@@ -925,6 +981,7 @@ int kvm_arm_pmu_v3_has_attr(struct kvm_vcpu *vcpu, struct kvm_device_attr *attr)
switch (attr->attr) {
case KVM_ARM_VCPU_PMU_V3_IRQ:
case KVM_ARM_VCPU_PMU_V3_INIT:
+ case KVM_ARM_VCPU_PMU_V3_FILTER:
if (kvm_arm_support_pmu_v3() &&
test_bit(KVM_ARM_VCPU_PMU_V3, vcpu->arch.features))
return 0;