return false;
}
+static inline bool kvm_set_pmuserenr(u64 val)
+{
+ return false;
+}
+
/* PMU Version in DFR Register */
#define ARMV8_PMU_DFR_VER_NI 0
#define ARMV8_PMU_DFR_VER_V3P4 0x5
#define SYSREGS_ON_CPU __vcpu_single_flag(sflags, BIT(4))
/* Software step state is Active-pending */
#define DBG_SS_ACTIVE_PENDING __vcpu_single_flag(sflags, BIT(5))
+/* PMUSERENR for the guest EL0 is on physical CPU */
+#define PMUSERENR_ON_CPU __vcpu_single_flag(sflags, BIT(6))
/* Pointer to the vcpu's SVE FFR for sve_{save,load}_state() */
#ifdef CONFIG_KVM
void kvm_set_pmu_events(u32 set, struct perf_event_attr *attr);
void kvm_clr_pmu_events(u32 clr);
+bool kvm_set_pmuserenr(u64 val);
#else
static inline void kvm_set_pmu_events(u32 set, struct perf_event_attr *attr) {}
static inline void kvm_clr_pmu_events(u32 clr) {}
+static inline bool kvm_set_pmuserenr(u64 val)
+{
+ return false;
+}
#endif
void kvm_vcpu_load_sysregs_vhe(struct kvm_vcpu *vcpu);
* EL1 instead of being trapped to EL2.
*/
if (kvm_arm_support_pmu_v3()) {
+ struct kvm_cpu_context *hctxt;
+
write_sysreg(0, pmselr_el0);
+
+ hctxt = &this_cpu_ptr(&kvm_host_data)->host_ctxt;
+ ctxt_sys_reg(hctxt, PMUSERENR_EL0) = read_sysreg(pmuserenr_el0);
write_sysreg(ARMV8_PMU_USERENR_MASK, pmuserenr_el0);
+ vcpu_set_flag(vcpu, PMUSERENR_ON_CPU);
}
vcpu->arch.mdcr_el2_host = read_sysreg(mdcr_el2);
write_sysreg(vcpu->arch.mdcr_el2_host, mdcr_el2);
write_sysreg(0, hstr_el2);
- if (kvm_arm_support_pmu_v3())
- write_sysreg(0, pmuserenr_el0);
+ if (kvm_arm_support_pmu_v3()) {
+ struct kvm_cpu_context *hctxt;
+
+ hctxt = &this_cpu_ptr(&kvm_host_data)->host_ctxt;
+ write_sysreg(ctxt_sys_reg(hctxt, PMUSERENR_EL0), pmuserenr_el0);
+ vcpu_clear_flag(vcpu, PMUSERENR_ON_CPU);
+ }
if (cpus_have_final_cap(ARM64_SME)) {
sysreg_clear_set_s(SYS_HFGRTR_EL2, 0,
}
NOKPROBE_SYMBOL(__deactivate_traps);
+/*
+ * Disable IRQs in {activate,deactivate}_traps_vhe_{load,put}() to
+ * prevent a race condition between context switching of PMUSERENR_EL0
+ * in __{activate,deactivate}_traps_common() and IPIs that attempts to
+ * update PMUSERENR_EL0. See also kvm_set_pmuserenr().
+ */
void activate_traps_vhe_load(struct kvm_vcpu *vcpu)
{
+ unsigned long flags;
+
+ local_irq_save(flags);
__activate_traps_common(vcpu);
+ local_irq_restore(flags);
}
void deactivate_traps_vhe_put(struct kvm_vcpu *vcpu)
{
+ unsigned long flags;
+
+ local_irq_save(flags);
__deactivate_traps_common(vcpu);
+ local_irq_restore(flags);
}
static const exit_handler_fn hyp_exit_handlers[] = {
mutex_lock(&arm_pmus_lock);
- cpu = smp_processor_id();
+ /*
+ * It is safe to use a stale cpu to iterate the list of PMUs so long as
+ * the same value is used for the entirety of the loop. Given this, and
+ * the fact that no percpu data is used for the lookup there is no need
+ * to disable preemption.
+ *
+ * It is still necessary to get a valid cpu, though, to probe for the
+ * default PMU instance as userspace is not required to specify a PMU
+ * type. In order to uphold the preexisting behavior KVM selects the
+ * PMU instance for the core where the first call to the
+ * KVM_ARM_VCPU_PMU_V3_CTRL attribute group occurs. A dependent use case
+ * would be a user with disdain of all things big.LITTLE that affines
+ * the VMM to a particular cluster of cores.
+ *
+ * In any case, userspace should just do the sane thing and use the UAPI
+ * to select a PMU type directly. But, be wary of the baggage being
+ * carried here.
+ */
+ cpu = raw_smp_processor_id();
list_for_each_entry(entry, &arm_pmus, entry) {
tmp = entry->arm_pmu;
kvm_vcpu_pmu_enable_el0(events_host);
kvm_vcpu_pmu_disable_el0(events_guest);
}
+
+/*
+ * With VHE, keep track of the PMUSERENR_EL0 value for the host EL0 on the pCPU
+ * where PMUSERENR_EL0 for the guest is loaded, since PMUSERENR_EL0 is switched
+ * to the value for the guest on vcpu_load(). The value for the host EL0
+ * will be restored on vcpu_put(), before returning to userspace.
+ * This isn't necessary for nVHE, as the register is context switched for
+ * every guest enter/exit.
+ *
+ * Return true if KVM takes care of the register. Otherwise return false.
+ */
+bool kvm_set_pmuserenr(u64 val)
+{
+ struct kvm_cpu_context *hctxt;
+ struct kvm_vcpu *vcpu;
+
+ if (!kvm_arm_support_pmu_v3() || !has_vhe())
+ return false;
+
+ vcpu = kvm_get_running_vcpu();
+ if (!vcpu || !vcpu_get_flag(vcpu, PMUSERENR_ON_CPU))
+ return false;
+
+ hctxt = &this_cpu_ptr(&kvm_host_data)->host_ctxt;
+ ctxt_sys_reg(hctxt, PMUSERENR_EL0) = val;
+ return true;
+}
int kvm_vgic_map_resources(struct kvm *kvm)
{
struct vgic_dist *dist = &kvm->arch.vgic;
+ enum vgic_type type;
gpa_t dist_base;
int ret = 0;
if (!irqchip_in_kernel(kvm))
goto out;
- if (dist->vgic_model == KVM_DEV_TYPE_ARM_VGIC_V2)
+ if (dist->vgic_model == KVM_DEV_TYPE_ARM_VGIC_V2) {
ret = vgic_v2_map_resources(kvm);
- else
+ type = VGIC_V2;
+ } else {
ret = vgic_v3_map_resources(kvm);
+ type = VGIC_V3;
+ }
if (ret) {
__kvm_vgic_destroy(kvm);
dist_base = dist->vgic_dist_base;
mutex_unlock(&kvm->arch.config_lock);
- ret = vgic_register_dist_iodev(kvm, dist_base,
- kvm_vgic_global_state.type);
+ ret = vgic_register_dist_iodev(kvm, dist_base, type);
if (ret) {
kvm_err("Unable to register VGIC dist MMIO regions\n");
kvm_vgic_destroy(kvm);
return value;
}
+static void update_pmuserenr(u64 val)
+{
+ lockdep_assert_irqs_disabled();
+
+ /*
+ * The current PMUSERENR_EL0 value might be the value for the guest.
+ * If that's the case, have KVM keep tracking of the register value
+ * for the host EL0 so that KVM can restore it before returning to
+ * the host EL0. Otherwise, update the register now.
+ */
+ if (kvm_set_pmuserenr(val))
+ return;
+
+ write_pmuserenr(val);
+}
+
static void armv8pmu_disable_user_access(void)
{
- write_pmuserenr(0);
+ update_pmuserenr(0);
}
static void armv8pmu_enable_user_access(struct arm_pmu *cpu_pmu)
armv8pmu_write_evcntr(i, 0);
}
- write_pmuserenr(0);
- write_pmuserenr(ARMV8_PMU_USERENR_ER | ARMV8_PMU_USERENR_CR);
+ update_pmuserenr(ARMV8_PMU_USERENR_ER | ARMV8_PMU_USERENR_CR);
}
static void armv8pmu_enable_event(struct perf_event *event)
return __kvm_handle_hva_range(kvm, &range);
}
+
+static bool kvm_change_spte_gfn(struct kvm *kvm, struct kvm_gfn_range *range)
+{
+ /*
+ * Skipping invalid memslots is correct if and only change_pte() is
+ * surrounded by invalidate_range_{start,end}(), which is currently
+ * guaranteed by the primary MMU. If that ever changes, KVM needs to
+ * unmap the memslot instead of skipping the memslot to ensure that KVM
+ * doesn't hold references to the old PFN.
+ */
+ WARN_ON_ONCE(!READ_ONCE(kvm->mn_active_invalidate_count));
+
+ if (range->slot->flags & KVM_MEMSLOT_INVALID)
+ return false;
+
+ return kvm_set_spte_gfn(kvm, range);
+}
+
static void kvm_mmu_notifier_change_pte(struct mmu_notifier *mn,
struct mm_struct *mm,
unsigned long address,
if (!READ_ONCE(kvm->mmu_invalidate_in_progress))
return;
- kvm_handle_hva_range(mn, address, address + 1, pte, kvm_set_spte_gfn);
+ kvm_handle_hva_range(mn, address, address + 1, pte, kvm_change_spte_gfn);
}
void kvm_mmu_invalidate_begin(struct kvm *kvm, unsigned long start,