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 does't need to be backed by a perf event */ - if (eventsel == ARMV8_PMUV3_PERFCTR_SW_INCR && - pmc->idx != ARMV8_PMU_CYCLE_IDX) + /* Software increment event doesn't need to be backed by a perf event */ + if (eventsel == ARMV8_PMUV3_PERFCTR_SW_INCR) + return; + + /* + * 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;