diff options
Diffstat (limited to 'arch/arm64/kvm/arm.c')
-rw-r--r-- | arch/arm64/kvm/arm.c | 196 |
1 files changed, 118 insertions, 78 deletions
diff --git a/arch/arm64/kvm/arm.c b/arch/arm64/kvm/arm.c index e4727dc771bf..4dca6ffd03d4 100644 --- a/arch/arm64/kvm/arm.c +++ b/arch/arm64/kvm/arm.c @@ -146,7 +146,7 @@ int kvm_arch_init_vm(struct kvm *kvm, unsigned long type) if (ret) return ret; - ret = create_hyp_mappings(kvm, kvm + 1, PAGE_HYP); + ret = kvm_share_hyp(kvm, kvm + 1); if (ret) goto out_free_stage2_pgd; @@ -175,19 +175,13 @@ vm_fault_t kvm_arch_vcpu_fault(struct kvm_vcpu *vcpu, struct vm_fault *vmf) */ 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) { - if (kvm->vcpus[i]) { - kvm_vcpu_destroy(kvm->vcpus[i]); - kvm->vcpus[i] = NULL; - } - } - atomic_set(&kvm->online_vcpus, 0); + kvm_destroy_vcpus(kvm); + + kvm_unshare_hyp(kvm, kvm + 1); } int kvm_vm_ioctl_check_extension(struct kvm *kvm, long ext) @@ -342,7 +336,7 @@ int kvm_arch_vcpu_create(struct kvm_vcpu *vcpu) if (err) return err; - return create_hyp_mappings(vcpu, vcpu + 1, PAGE_HYP); + return kvm_share_hyp(vcpu, vcpu + 1); } void kvm_arch_vcpu_postcreate(struct kvm_vcpu *vcpu) @@ -351,7 +345,7 @@ void kvm_arch_vcpu_postcreate(struct kvm_vcpu *vcpu) void kvm_arch_vcpu_destroy(struct kvm_vcpu *vcpu) { - if (vcpu->arch.has_run_once && unlikely(!irqchip_in_kernel(vcpu->kvm))) + if (vcpu_has_run_once(vcpu) && unlikely(!irqchip_in_kernel(vcpu->kvm))) static_branch_dec(&userspace_irqchip_in_use); kvm_mmu_free_memory_cache(&vcpu->arch.mmu_page_cache); @@ -368,27 +362,12 @@ int kvm_cpu_has_pending_timer(struct kvm_vcpu *vcpu) void kvm_arch_vcpu_blocking(struct kvm_vcpu *vcpu) { - /* - * If we're about to block (most likely because we've just hit a - * WFI), we need to sync back the state of the GIC CPU interface - * so that we have the latest PMR and group enables. This ensures - * that kvm_arch_vcpu_runnable has up-to-date data to decide - * whether we have pending interrupts. - * - * For the same reason, we want to tell GICv4 that we need - * doorbells to be signalled, should an interrupt become pending. - */ - preempt_disable(); - kvm_vgic_vmcr_sync(vcpu); - vgic_v4_put(vcpu, true); - preempt_enable(); + } void kvm_arch_vcpu_unblocking(struct kvm_vcpu *vcpu) { - preempt_disable(); - vgic_v4_load(vcpu); - preempt_enable(); + } void kvm_arch_vcpu_load(struct kvm_vcpu *vcpu, int cpu) @@ -503,6 +482,13 @@ bool kvm_arch_vcpu_in_kernel(struct kvm_vcpu *vcpu) return vcpu_mode_priv(vcpu); } +#ifdef CONFIG_GUEST_PERF_EVENTS +unsigned long kvm_arch_vcpu_get_ip(struct kvm_vcpu *vcpu) +{ + return *vcpu_pc(vcpu); +} +#endif + /* Just ensure a guest exit from a particular CPU */ static void exit_vm_noop(void *info) { @@ -584,18 +570,33 @@ static void update_vmid(struct kvm_vmid *vmid) spin_unlock(&kvm_vmid_lock); } -static int kvm_vcpu_first_run_init(struct kvm_vcpu *vcpu) +static int kvm_vcpu_initialized(struct kvm_vcpu *vcpu) +{ + return vcpu->arch.target >= 0; +} + +/* + * Handle both the initialisation that is being done when the vcpu is + * run for the first time, as well as the updates that must be + * performed each time we get a new thread dealing with this vcpu. + */ +int kvm_arch_vcpu_run_pid_change(struct kvm_vcpu *vcpu) { struct kvm *kvm = vcpu->kvm; - int ret = 0; + int ret; - if (likely(vcpu->arch.has_run_once)) - return 0; + if (!kvm_vcpu_initialized(vcpu)) + return -ENOEXEC; if (!kvm_arm_vcpu_is_finalized(vcpu)) return -EPERM; - vcpu->arch.has_run_once = true; + ret = kvm_arch_vcpu_run_map_fp(vcpu); + if (ret) + return ret; + + if (likely(vcpu_has_run_once(vcpu))) + return 0; kvm_arm_vcpu_init_debug(vcpu); @@ -607,12 +608,6 @@ static int kvm_vcpu_first_run_init(struct kvm_vcpu *vcpu) ret = kvm_vgic_map_resources(kvm); if (ret) return ret; - } else { - /* - * Tell the rest of the code that there are userspace irqchip - * VMs in the wild. - */ - static_branch_inc(&userspace_irqchip_in_use); } ret = kvm_timer_enable(vcpu); @@ -620,6 +615,16 @@ static int kvm_vcpu_first_run_init(struct kvm_vcpu *vcpu) return ret; ret = kvm_arm_pmu_v3_enable(vcpu); + if (ret) + return ret; + + if (!irqchip_in_kernel(kvm)) { + /* + * Tell the rest of the code that there are userspace irqchip + * VMs in the wild. + */ + static_branch_inc(&userspace_irqchip_in_use); + } /* * Initialize traps for protected VMs. @@ -639,7 +644,7 @@ bool kvm_arch_intc_initialized(struct kvm *kvm) void kvm_arm_halt_guest(struct kvm *kvm) { - int i; + unsigned long i; struct kvm_vcpu *vcpu; kvm_for_each_vcpu(i, vcpu, kvm) @@ -649,12 +654,12 @@ void kvm_arm_halt_guest(struct kvm *kvm) void kvm_arm_resume_guest(struct kvm *kvm) { - int i; + unsigned long i; struct kvm_vcpu *vcpu; kvm_for_each_vcpu(i, vcpu, kvm) { vcpu->arch.pause = false; - rcuwait_wake_up(kvm_arch_vcpu_get_wait(vcpu)); + __kvm_vcpu_wake_up(vcpu); } } @@ -679,9 +684,37 @@ static void vcpu_req_sleep(struct kvm_vcpu *vcpu) smp_rmb(); } -static int kvm_vcpu_initialized(struct kvm_vcpu *vcpu) +/** + * kvm_vcpu_wfi - emulate Wait-For-Interrupt behavior + * @vcpu: The VCPU pointer + * + * Suspend execution of a vCPU until a valid wake event is detected, i.e. until + * the vCPU is runnable. The vCPU may or may not be scheduled out, depending + * on when a wake event arrives, e.g. there may already be a pending wake event. + */ +void kvm_vcpu_wfi(struct kvm_vcpu *vcpu) { - return vcpu->arch.target >= 0; + /* + * Sync back the state of the GIC CPU interface so that we have + * the latest PMR and group enables. This ensures that + * kvm_arch_vcpu_runnable has up-to-date data to decide whether + * we have pending interrupts, e.g. when determining if the + * vCPU should block. + * + * For the same reason, we want to tell GICv4 that we need + * doorbells to be signalled, should an interrupt become pending. + */ + preempt_disable(); + kvm_vgic_vmcr_sync(vcpu); + vgic_v4_put(vcpu, true); + preempt_enable(); + + kvm_vcpu_halt(vcpu); + kvm_clear_request(KVM_REQ_UNHALT, vcpu); + + preempt_disable(); + vgic_v4_load(vcpu); + preempt_enable(); } static void check_vcpu_requests(struct kvm_vcpu *vcpu) @@ -764,6 +797,24 @@ static bool kvm_vcpu_exit_request(struct kvm_vcpu *vcpu, int *ret) xfer_to_guest_mode_work_pending(); } +/* + * Actually run the vCPU, entering an RCU extended quiescent state (EQS) while + * the vCPU is running. + * + * This must be noinstr as instrumentation may make use of RCU, and this is not + * safe during the EQS. + */ +static int noinstr kvm_arm_vcpu_enter_exit(struct kvm_vcpu *vcpu) +{ + int ret; + + guest_state_enter_irqoff(); + ret = kvm_call_hyp_ret(__kvm_vcpu_run, vcpu); + guest_state_exit_irqoff(); + + return ret; +} + /** * kvm_arch_vcpu_ioctl_run - the main VCPU run function to execute guest code * @vcpu: The VCPU pointer @@ -779,13 +830,6 @@ int kvm_arch_vcpu_ioctl_run(struct kvm_vcpu *vcpu) struct kvm_run *run = vcpu->run; int ret; - if (unlikely(!kvm_vcpu_initialized(vcpu))) - return -ENOEXEC; - - ret = kvm_vcpu_first_run_init(vcpu); - if (ret) - return ret; - if (run->exit_reason == KVM_EXIT_MMIO) { ret = kvm_handle_mmio_return(vcpu); if (ret) @@ -849,14 +893,15 @@ int kvm_arch_vcpu_ioctl_run(struct kvm_vcpu *vcpu) } kvm_arm_setup_debug(vcpu); + kvm_arch_vcpu_ctxflush_fp(vcpu); /************************************************************** * Enter the guest */ trace_kvm_entry(*vcpu_pc(vcpu)); - guest_enter_irqoff(); + guest_timing_enter_irqoff(); - ret = kvm_call_hyp_ret(__kvm_vcpu_run, vcpu); + ret = kvm_arm_vcpu_enter_exit(vcpu); vcpu->mode = OUTSIDE_GUEST_MODE; vcpu->stat.exits++; @@ -891,26 +936,23 @@ int kvm_arch_vcpu_ioctl_run(struct kvm_vcpu *vcpu) kvm_arch_vcpu_ctxsync_fp(vcpu); /* - * We may have taken a host interrupt in HYP mode (ie - * while executing the guest). This interrupt is still - * pending, as we haven't serviced it yet! + * We must ensure that any pending interrupts are taken before + * we exit guest timing so that timer ticks are accounted as + * guest time. Transiently unmask interrupts so that any + * pending interrupts are taken. * - * We're now back in SVC mode, with interrupts - * disabled. Enabling the interrupts now will have - * the effect of taking the interrupt again, in SVC - * mode this time. + * Per ARM DDI 0487G.b section D1.13.4, an ISB (or other + * context synchronization event) is necessary to ensure that + * pending interrupts are taken. */ local_irq_enable(); + isb(); + local_irq_disable(); + + guest_timing_exit_irqoff(); + + local_irq_enable(); - /* - * We do local_irq_enable() before calling guest_exit() so - * that if a timer interrupt hits while running the guest we - * account that tick as being spent in the guest. We enable - * preemption after calling guest_exit() so that if we get - * preempted we make sure ticks after that is not counted as - * guest time. - */ - guest_exit(); trace_kvm_exit(ret, kvm_vcpu_trap_get_class(vcpu), *vcpu_pc(vcpu)); /* Exit types that need handling before we can be preempted */ @@ -1123,7 +1165,7 @@ static int kvm_arch_vcpu_ioctl_vcpu_init(struct kvm_vcpu *vcpu, * need to invalidate the I-cache though, as FWB does *not* * imply CTR_EL0.DIC. */ - if (vcpu->arch.has_run_once) { + if (vcpu_has_run_once(vcpu)) { if (!cpus_have_final_cap(ARM64_HAS_STAGE2_FWB)) stage2_unmap_vm(vcpu->kvm); else @@ -1449,10 +1491,7 @@ static int kvm_init_vector_slots(void) base = kern_hyp_va(kvm_ksym_ref(__bp_harden_hyp_vecs)); kvm_init_vector_slot(base, HYP_VECTOR_SPECTRE_DIRECT); - if (!cpus_have_const_cap(ARM64_SPECTRE_V3A)) - return 0; - - if (!has_vhe()) { + if (kvm_system_needs_idmapped_vectors() && !has_vhe()) { err = create_hyp_exec_mappings(__pa_symbol(__bp_harden_hyp_vecs), __BP_HARDEN_HYP_VECS_SZ, &base); if (err) @@ -1775,7 +1814,8 @@ static int init_subsystems(void) if (err) goto out; - kvm_perf_init(); + kvm_register_perf_callbacks(NULL); + kvm_sys_reg_table_init(); out: @@ -2035,7 +2075,7 @@ static int finalize_hyp_mode(void) struct kvm_vcpu *kvm_mpidr_to_vcpu(struct kvm *kvm, unsigned long mpidr) { struct kvm_vcpu *vcpu; - int i; + unsigned long i; mpidr &= MPIDR_HWID_BITMASK; kvm_for_each_vcpu(i, vcpu, kvm) { @@ -2163,7 +2203,7 @@ out_err: /* NOP: Compiling as a module not supported */ void kvm_arch_exit(void) { - kvm_perf_teardown(); + kvm_unregister_perf_callbacks(); } static int __init early_kvm_mode_cfg(char *arg) |