1 // SPDX-License-Identifier: GPL-2.0-only 2 /* 3 * Copyright (C) 2012 - Virtual Open Systems and Columbia University 4 * Author: Christoffer Dall <c.dall@virtualopensystems.com> 5 */ 6 7 #include <linux/bug.h> 8 #include <linux/cpu_pm.h> 9 #include <linux/entry-kvm.h> 10 #include <linux/errno.h> 11 #include <linux/err.h> 12 #include <linux/kvm_host.h> 13 #include <linux/list.h> 14 #include <linux/module.h> 15 #include <linux/vmalloc.h> 16 #include <linux/fs.h> 17 #include <linux/mman.h> 18 #include <linux/sched.h> 19 #include <linux/kvm.h> 20 #include <linux/kvm_irqfd.h> 21 #include <linux/irqbypass.h> 22 #include <linux/sched/stat.h> 23 #include <linux/psci.h> 24 #include <trace/events/kvm.h> 25 26 #define CREATE_TRACE_POINTS 27 #include "trace_arm.h" 28 29 #include <linux/uaccess.h> 30 #include <asm/ptrace.h> 31 #include <asm/mman.h> 32 #include <asm/tlbflush.h> 33 #include <asm/cacheflush.h> 34 #include <asm/cpufeature.h> 35 #include <asm/virt.h> 36 #include <asm/kvm_arm.h> 37 #include <asm/kvm_asm.h> 38 #include <asm/kvm_mmu.h> 39 #include <asm/kvm_pkvm.h> 40 #include <asm/kvm_emulate.h> 41 #include <asm/sections.h> 42 43 #include <kvm/arm_hypercalls.h> 44 #include <kvm/arm_pmu.h> 45 #include <kvm/arm_psci.h> 46 47 static enum kvm_mode kvm_mode = KVM_MODE_DEFAULT; 48 49 DECLARE_KVM_HYP_PER_CPU(unsigned long, kvm_hyp_vector); 50 51 DEFINE_PER_CPU(unsigned long, kvm_arm_hyp_stack_page); 52 DECLARE_KVM_NVHE_PER_CPU(struct kvm_nvhe_init_params, kvm_init_params); 53 54 DECLARE_KVM_NVHE_PER_CPU(struct kvm_cpu_context, kvm_hyp_ctxt); 55 56 static bool vgic_present, kvm_arm_initialised; 57 58 static DEFINE_PER_CPU(unsigned char, kvm_arm_hardware_enabled); 59 DEFINE_STATIC_KEY_FALSE(userspace_irqchip_in_use); 60 61 bool is_kvm_arm_initialised(void) 62 { 63 return kvm_arm_initialised; 64 } 65 66 int kvm_arch_vcpu_should_kick(struct kvm_vcpu *vcpu) 67 { 68 return kvm_vcpu_exiting_guest_mode(vcpu) == IN_GUEST_MODE; 69 } 70 71 int kvm_vm_ioctl_enable_cap(struct kvm *kvm, 72 struct kvm_enable_cap *cap) 73 { 74 int r; 75 u64 new_cap; 76 77 if (cap->flags) 78 return -EINVAL; 79 80 switch (cap->cap) { 81 case KVM_CAP_ARM_NISV_TO_USER: 82 r = 0; 83 set_bit(KVM_ARCH_FLAG_RETURN_NISV_IO_ABORT_TO_USER, 84 &kvm->arch.flags); 85 break; 86 case KVM_CAP_ARM_MTE: 87 mutex_lock(&kvm->lock); 88 if (!system_supports_mte() || kvm->created_vcpus) { 89 r = -EINVAL; 90 } else { 91 r = 0; 92 set_bit(KVM_ARCH_FLAG_MTE_ENABLED, &kvm->arch.flags); 93 } 94 mutex_unlock(&kvm->lock); 95 break; 96 case KVM_CAP_ARM_SYSTEM_SUSPEND: 97 r = 0; 98 set_bit(KVM_ARCH_FLAG_SYSTEM_SUSPEND_ENABLED, &kvm->arch.flags); 99 break; 100 case KVM_CAP_ARM_EAGER_SPLIT_CHUNK_SIZE: 101 new_cap = cap->args[0]; 102 103 mutex_lock(&kvm->slots_lock); 104 /* 105 * To keep things simple, allow changing the chunk 106 * size only when no memory slots have been created. 107 */ 108 if (!kvm_are_all_memslots_empty(kvm)) { 109 r = -EINVAL; 110 } else if (new_cap && !kvm_is_block_size_supported(new_cap)) { 111 r = -EINVAL; 112 } else { 113 r = 0; 114 kvm->arch.mmu.split_page_chunk_size = new_cap; 115 } 116 mutex_unlock(&kvm->slots_lock); 117 break; 118 default: 119 r = -EINVAL; 120 break; 121 } 122 123 return r; 124 } 125 126 static int kvm_arm_default_max_vcpus(void) 127 { 128 return vgic_present ? kvm_vgic_get_max_vcpus() : KVM_MAX_VCPUS; 129 } 130 131 /** 132 * kvm_arch_init_vm - initializes a VM data structure 133 * @kvm: pointer to the KVM struct 134 */ 135 int kvm_arch_init_vm(struct kvm *kvm, unsigned long type) 136 { 137 int ret; 138 139 mutex_init(&kvm->arch.config_lock); 140 141 #ifdef CONFIG_LOCKDEP 142 /* Clue in lockdep that the config_lock must be taken inside kvm->lock */ 143 mutex_lock(&kvm->lock); 144 mutex_lock(&kvm->arch.config_lock); 145 mutex_unlock(&kvm->arch.config_lock); 146 mutex_unlock(&kvm->lock); 147 #endif 148 149 ret = kvm_share_hyp(kvm, kvm + 1); 150 if (ret) 151 return ret; 152 153 ret = pkvm_init_host_vm(kvm); 154 if (ret) 155 goto err_unshare_kvm; 156 157 if (!zalloc_cpumask_var(&kvm->arch.supported_cpus, GFP_KERNEL_ACCOUNT)) { 158 ret = -ENOMEM; 159 goto err_unshare_kvm; 160 } 161 cpumask_copy(kvm->arch.supported_cpus, cpu_possible_mask); 162 163 ret = kvm_init_stage2_mmu(kvm, &kvm->arch.mmu, type); 164 if (ret) 165 goto err_free_cpumask; 166 167 kvm_vgic_early_init(kvm); 168 169 kvm_timer_init_vm(kvm); 170 171 /* The maximum number of VCPUs is limited by the host's GIC model */ 172 kvm->max_vcpus = kvm_arm_default_max_vcpus(); 173 174 kvm_arm_init_hypercalls(kvm); 175 176 bitmap_zero(kvm->arch.vcpu_features, KVM_VCPU_MAX_FEATURES); 177 178 return 0; 179 180 err_free_cpumask: 181 free_cpumask_var(kvm->arch.supported_cpus); 182 err_unshare_kvm: 183 kvm_unshare_hyp(kvm, kvm + 1); 184 return ret; 185 } 186 187 vm_fault_t kvm_arch_vcpu_fault(struct kvm_vcpu *vcpu, struct vm_fault *vmf) 188 { 189 return VM_FAULT_SIGBUS; 190 } 191 192 193 /** 194 * kvm_arch_destroy_vm - destroy the VM data structure 195 * @kvm: pointer to the KVM struct 196 */ 197 void kvm_arch_destroy_vm(struct kvm *kvm) 198 { 199 bitmap_free(kvm->arch.pmu_filter); 200 free_cpumask_var(kvm->arch.supported_cpus); 201 202 kvm_vgic_destroy(kvm); 203 204 if (is_protected_kvm_enabled()) 205 pkvm_destroy_hyp_vm(kvm); 206 207 kvm_destroy_vcpus(kvm); 208 209 kvm_unshare_hyp(kvm, kvm + 1); 210 211 kvm_arm_teardown_hypercalls(kvm); 212 } 213 214 int kvm_vm_ioctl_check_extension(struct kvm *kvm, long ext) 215 { 216 int r; 217 switch (ext) { 218 case KVM_CAP_IRQCHIP: 219 r = vgic_present; 220 break; 221 case KVM_CAP_IOEVENTFD: 222 case KVM_CAP_DEVICE_CTRL: 223 case KVM_CAP_USER_MEMORY: 224 case KVM_CAP_SYNC_MMU: 225 case KVM_CAP_DESTROY_MEMORY_REGION_WORKS: 226 case KVM_CAP_ONE_REG: 227 case KVM_CAP_ARM_PSCI: 228 case KVM_CAP_ARM_PSCI_0_2: 229 case KVM_CAP_READONLY_MEM: 230 case KVM_CAP_MP_STATE: 231 case KVM_CAP_IMMEDIATE_EXIT: 232 case KVM_CAP_VCPU_EVENTS: 233 case KVM_CAP_ARM_IRQ_LINE_LAYOUT_2: 234 case KVM_CAP_ARM_NISV_TO_USER: 235 case KVM_CAP_ARM_INJECT_EXT_DABT: 236 case KVM_CAP_SET_GUEST_DEBUG: 237 case KVM_CAP_VCPU_ATTRIBUTES: 238 case KVM_CAP_PTP_KVM: 239 case KVM_CAP_ARM_SYSTEM_SUSPEND: 240 case KVM_CAP_IRQFD_RESAMPLE: 241 case KVM_CAP_COUNTER_OFFSET: 242 r = 1; 243 break; 244 case KVM_CAP_SET_GUEST_DEBUG2: 245 return KVM_GUESTDBG_VALID_MASK; 246 case KVM_CAP_ARM_SET_DEVICE_ADDR: 247 r = 1; 248 break; 249 case KVM_CAP_NR_VCPUS: 250 /* 251 * ARM64 treats KVM_CAP_NR_CPUS differently from all other 252 * architectures, as it does not always bound it to 253 * KVM_CAP_MAX_VCPUS. It should not matter much because 254 * this is just an advisory value. 255 */ 256 r = min_t(unsigned int, num_online_cpus(), 257 kvm_arm_default_max_vcpus()); 258 break; 259 case KVM_CAP_MAX_VCPUS: 260 case KVM_CAP_MAX_VCPU_ID: 261 if (kvm) 262 r = kvm->max_vcpus; 263 else 264 r = kvm_arm_default_max_vcpus(); 265 break; 266 case KVM_CAP_MSI_DEVID: 267 if (!kvm) 268 r = -EINVAL; 269 else 270 r = kvm->arch.vgic.msis_require_devid; 271 break; 272 case KVM_CAP_ARM_USER_IRQ: 273 /* 274 * 1: EL1_VTIMER, EL1_PTIMER, and PMU. 275 * (bump this number if adding more devices) 276 */ 277 r = 1; 278 break; 279 case KVM_CAP_ARM_MTE: 280 r = system_supports_mte(); 281 break; 282 case KVM_CAP_STEAL_TIME: 283 r = kvm_arm_pvtime_supported(); 284 break; 285 case KVM_CAP_ARM_EL1_32BIT: 286 r = cpus_have_const_cap(ARM64_HAS_32BIT_EL1); 287 break; 288 case KVM_CAP_GUEST_DEBUG_HW_BPS: 289 r = get_num_brps(); 290 break; 291 case KVM_CAP_GUEST_DEBUG_HW_WPS: 292 r = get_num_wrps(); 293 break; 294 case KVM_CAP_ARM_PMU_V3: 295 r = kvm_arm_support_pmu_v3(); 296 break; 297 case KVM_CAP_ARM_INJECT_SERROR_ESR: 298 r = cpus_have_const_cap(ARM64_HAS_RAS_EXTN); 299 break; 300 case KVM_CAP_ARM_VM_IPA_SIZE: 301 r = get_kvm_ipa_limit(); 302 break; 303 case KVM_CAP_ARM_SVE: 304 r = system_supports_sve(); 305 break; 306 case KVM_CAP_ARM_PTRAUTH_ADDRESS: 307 case KVM_CAP_ARM_PTRAUTH_GENERIC: 308 r = system_has_full_ptr_auth(); 309 break; 310 case KVM_CAP_ARM_EAGER_SPLIT_CHUNK_SIZE: 311 if (kvm) 312 r = kvm->arch.mmu.split_page_chunk_size; 313 else 314 r = KVM_ARM_EAGER_SPLIT_CHUNK_SIZE_DEFAULT; 315 break; 316 case KVM_CAP_ARM_SUPPORTED_BLOCK_SIZES: 317 r = kvm_supported_block_sizes(); 318 break; 319 default: 320 r = 0; 321 } 322 323 return r; 324 } 325 326 long kvm_arch_dev_ioctl(struct file *filp, 327 unsigned int ioctl, unsigned long arg) 328 { 329 return -EINVAL; 330 } 331 332 struct kvm *kvm_arch_alloc_vm(void) 333 { 334 size_t sz = sizeof(struct kvm); 335 336 if (!has_vhe()) 337 return kzalloc(sz, GFP_KERNEL_ACCOUNT); 338 339 return __vmalloc(sz, GFP_KERNEL_ACCOUNT | __GFP_HIGHMEM | __GFP_ZERO); 340 } 341 342 int kvm_arch_vcpu_precreate(struct kvm *kvm, unsigned int id) 343 { 344 if (irqchip_in_kernel(kvm) && vgic_initialized(kvm)) 345 return -EBUSY; 346 347 if (id >= kvm->max_vcpus) 348 return -EINVAL; 349 350 return 0; 351 } 352 353 int kvm_arch_vcpu_create(struct kvm_vcpu *vcpu) 354 { 355 int err; 356 357 spin_lock_init(&vcpu->arch.mp_state_lock); 358 359 #ifdef CONFIG_LOCKDEP 360 /* Inform lockdep that the config_lock is acquired after vcpu->mutex */ 361 mutex_lock(&vcpu->mutex); 362 mutex_lock(&vcpu->kvm->arch.config_lock); 363 mutex_unlock(&vcpu->kvm->arch.config_lock); 364 mutex_unlock(&vcpu->mutex); 365 #endif 366 367 /* Force users to call KVM_ARM_VCPU_INIT */ 368 vcpu->arch.target = -1; 369 bitmap_zero(vcpu->arch.features, KVM_VCPU_MAX_FEATURES); 370 371 vcpu->arch.mmu_page_cache.gfp_zero = __GFP_ZERO; 372 373 /* 374 * Default value for the FP state, will be overloaded at load 375 * time if we support FP (pretty likely) 376 */ 377 vcpu->arch.fp_state = FP_STATE_FREE; 378 379 /* Set up the timer */ 380 kvm_timer_vcpu_init(vcpu); 381 382 kvm_pmu_vcpu_init(vcpu); 383 384 kvm_arm_reset_debug_ptr(vcpu); 385 386 kvm_arm_pvtime_vcpu_init(&vcpu->arch); 387 388 vcpu->arch.hw_mmu = &vcpu->kvm->arch.mmu; 389 390 err = kvm_vgic_vcpu_init(vcpu); 391 if (err) 392 return err; 393 394 return kvm_share_hyp(vcpu, vcpu + 1); 395 } 396 397 void kvm_arch_vcpu_postcreate(struct kvm_vcpu *vcpu) 398 { 399 } 400 401 void kvm_arch_vcpu_destroy(struct kvm_vcpu *vcpu) 402 { 403 if (vcpu_has_run_once(vcpu) && unlikely(!irqchip_in_kernel(vcpu->kvm))) 404 static_branch_dec(&userspace_irqchip_in_use); 405 406 kvm_mmu_free_memory_cache(&vcpu->arch.mmu_page_cache); 407 kvm_timer_vcpu_terminate(vcpu); 408 kvm_pmu_vcpu_destroy(vcpu); 409 410 kvm_arm_vcpu_destroy(vcpu); 411 } 412 413 void kvm_arch_vcpu_blocking(struct kvm_vcpu *vcpu) 414 { 415 416 } 417 418 void kvm_arch_vcpu_unblocking(struct kvm_vcpu *vcpu) 419 { 420 421 } 422 423 void kvm_arch_vcpu_load(struct kvm_vcpu *vcpu, int cpu) 424 { 425 struct kvm_s2_mmu *mmu; 426 int *last_ran; 427 428 mmu = vcpu->arch.hw_mmu; 429 last_ran = this_cpu_ptr(mmu->last_vcpu_ran); 430 431 /* 432 * We guarantee that both TLBs and I-cache are private to each 433 * vcpu. If detecting that a vcpu from the same VM has 434 * previously run on the same physical CPU, call into the 435 * hypervisor code to nuke the relevant contexts. 436 * 437 * We might get preempted before the vCPU actually runs, but 438 * over-invalidation doesn't affect correctness. 439 */ 440 if (*last_ran != vcpu->vcpu_id) { 441 kvm_call_hyp(__kvm_flush_cpu_context, mmu); 442 *last_ran = vcpu->vcpu_id; 443 } 444 445 vcpu->cpu = cpu; 446 447 kvm_vgic_load(vcpu); 448 kvm_timer_vcpu_load(vcpu); 449 if (has_vhe()) 450 kvm_vcpu_load_sysregs_vhe(vcpu); 451 kvm_arch_vcpu_load_fp(vcpu); 452 kvm_vcpu_pmu_restore_guest(vcpu); 453 if (kvm_arm_is_pvtime_enabled(&vcpu->arch)) 454 kvm_make_request(KVM_REQ_RECORD_STEAL, vcpu); 455 456 if (single_task_running()) 457 vcpu_clear_wfx_traps(vcpu); 458 else 459 vcpu_set_wfx_traps(vcpu); 460 461 if (vcpu_has_ptrauth(vcpu)) 462 vcpu_ptrauth_disable(vcpu); 463 kvm_arch_vcpu_load_debug_state_flags(vcpu); 464 465 if (!cpumask_test_cpu(smp_processor_id(), vcpu->kvm->arch.supported_cpus)) 466 vcpu_set_on_unsupported_cpu(vcpu); 467 } 468 469 void kvm_arch_vcpu_put(struct kvm_vcpu *vcpu) 470 { 471 kvm_arch_vcpu_put_debug_state_flags(vcpu); 472 kvm_arch_vcpu_put_fp(vcpu); 473 if (has_vhe()) 474 kvm_vcpu_put_sysregs_vhe(vcpu); 475 kvm_timer_vcpu_put(vcpu); 476 kvm_vgic_put(vcpu); 477 kvm_vcpu_pmu_restore_host(vcpu); 478 kvm_arm_vmid_clear_active(); 479 480 vcpu_clear_on_unsupported_cpu(vcpu); 481 vcpu->cpu = -1; 482 } 483 484 static void __kvm_arm_vcpu_power_off(struct kvm_vcpu *vcpu) 485 { 486 WRITE_ONCE(vcpu->arch.mp_state.mp_state, KVM_MP_STATE_STOPPED); 487 kvm_make_request(KVM_REQ_SLEEP, vcpu); 488 kvm_vcpu_kick(vcpu); 489 } 490 491 void kvm_arm_vcpu_power_off(struct kvm_vcpu *vcpu) 492 { 493 spin_lock(&vcpu->arch.mp_state_lock); 494 __kvm_arm_vcpu_power_off(vcpu); 495 spin_unlock(&vcpu->arch.mp_state_lock); 496 } 497 498 bool kvm_arm_vcpu_stopped(struct kvm_vcpu *vcpu) 499 { 500 return READ_ONCE(vcpu->arch.mp_state.mp_state) == KVM_MP_STATE_STOPPED; 501 } 502 503 static void kvm_arm_vcpu_suspend(struct kvm_vcpu *vcpu) 504 { 505 WRITE_ONCE(vcpu->arch.mp_state.mp_state, KVM_MP_STATE_SUSPENDED); 506 kvm_make_request(KVM_REQ_SUSPEND, vcpu); 507 kvm_vcpu_kick(vcpu); 508 } 509 510 static bool kvm_arm_vcpu_suspended(struct kvm_vcpu *vcpu) 511 { 512 return READ_ONCE(vcpu->arch.mp_state.mp_state) == KVM_MP_STATE_SUSPENDED; 513 } 514 515 int kvm_arch_vcpu_ioctl_get_mpstate(struct kvm_vcpu *vcpu, 516 struct kvm_mp_state *mp_state) 517 { 518 *mp_state = READ_ONCE(vcpu->arch.mp_state); 519 520 return 0; 521 } 522 523 int kvm_arch_vcpu_ioctl_set_mpstate(struct kvm_vcpu *vcpu, 524 struct kvm_mp_state *mp_state) 525 { 526 int ret = 0; 527 528 spin_lock(&vcpu->arch.mp_state_lock); 529 530 switch (mp_state->mp_state) { 531 case KVM_MP_STATE_RUNNABLE: 532 WRITE_ONCE(vcpu->arch.mp_state, *mp_state); 533 break; 534 case KVM_MP_STATE_STOPPED: 535 __kvm_arm_vcpu_power_off(vcpu); 536 break; 537 case KVM_MP_STATE_SUSPENDED: 538 kvm_arm_vcpu_suspend(vcpu); 539 break; 540 default: 541 ret = -EINVAL; 542 } 543 544 spin_unlock(&vcpu->arch.mp_state_lock); 545 546 return ret; 547 } 548 549 /** 550 * kvm_arch_vcpu_runnable - determine if the vcpu can be scheduled 551 * @v: The VCPU pointer 552 * 553 * If the guest CPU is not waiting for interrupts or an interrupt line is 554 * asserted, the CPU is by definition runnable. 555 */ 556 int kvm_arch_vcpu_runnable(struct kvm_vcpu *v) 557 { 558 bool irq_lines = *vcpu_hcr(v) & (HCR_VI | HCR_VF); 559 return ((irq_lines || kvm_vgic_vcpu_pending_irq(v)) 560 && !kvm_arm_vcpu_stopped(v) && !v->arch.pause); 561 } 562 563 bool kvm_arch_vcpu_in_kernel(struct kvm_vcpu *vcpu) 564 { 565 return vcpu_mode_priv(vcpu); 566 } 567 568 #ifdef CONFIG_GUEST_PERF_EVENTS 569 unsigned long kvm_arch_vcpu_get_ip(struct kvm_vcpu *vcpu) 570 { 571 return *vcpu_pc(vcpu); 572 } 573 #endif 574 575 static int kvm_vcpu_initialized(struct kvm_vcpu *vcpu) 576 { 577 return vcpu->arch.target >= 0; 578 } 579 580 /* 581 * Handle both the initialisation that is being done when the vcpu is 582 * run for the first time, as well as the updates that must be 583 * performed each time we get a new thread dealing with this vcpu. 584 */ 585 int kvm_arch_vcpu_run_pid_change(struct kvm_vcpu *vcpu) 586 { 587 struct kvm *kvm = vcpu->kvm; 588 int ret; 589 590 if (!kvm_vcpu_initialized(vcpu)) 591 return -ENOEXEC; 592 593 if (!kvm_arm_vcpu_is_finalized(vcpu)) 594 return -EPERM; 595 596 ret = kvm_arch_vcpu_run_map_fp(vcpu); 597 if (ret) 598 return ret; 599 600 if (likely(vcpu_has_run_once(vcpu))) 601 return 0; 602 603 kvm_arm_vcpu_init_debug(vcpu); 604 605 if (likely(irqchip_in_kernel(kvm))) { 606 /* 607 * Map the VGIC hardware resources before running a vcpu the 608 * first time on this VM. 609 */ 610 ret = kvm_vgic_map_resources(kvm); 611 if (ret) 612 return ret; 613 } 614 615 ret = kvm_timer_enable(vcpu); 616 if (ret) 617 return ret; 618 619 ret = kvm_arm_pmu_v3_enable(vcpu); 620 if (ret) 621 return ret; 622 623 if (is_protected_kvm_enabled()) { 624 ret = pkvm_create_hyp_vm(kvm); 625 if (ret) 626 return ret; 627 } 628 629 if (!irqchip_in_kernel(kvm)) { 630 /* 631 * Tell the rest of the code that there are userspace irqchip 632 * VMs in the wild. 633 */ 634 static_branch_inc(&userspace_irqchip_in_use); 635 } 636 637 /* 638 * Initialize traps for protected VMs. 639 * NOTE: Move to run in EL2 directly, rather than via a hypercall, once 640 * the code is in place for first run initialization at EL2. 641 */ 642 if (kvm_vm_is_protected(kvm)) 643 kvm_call_hyp_nvhe(__pkvm_vcpu_init_traps, vcpu); 644 645 mutex_lock(&kvm->arch.config_lock); 646 set_bit(KVM_ARCH_FLAG_HAS_RAN_ONCE, &kvm->arch.flags); 647 mutex_unlock(&kvm->arch.config_lock); 648 649 return ret; 650 } 651 652 bool kvm_arch_intc_initialized(struct kvm *kvm) 653 { 654 return vgic_initialized(kvm); 655 } 656 657 void kvm_arm_halt_guest(struct kvm *kvm) 658 { 659 unsigned long i; 660 struct kvm_vcpu *vcpu; 661 662 kvm_for_each_vcpu(i, vcpu, kvm) 663 vcpu->arch.pause = true; 664 kvm_make_all_cpus_request(kvm, KVM_REQ_SLEEP); 665 } 666 667 void kvm_arm_resume_guest(struct kvm *kvm) 668 { 669 unsigned long i; 670 struct kvm_vcpu *vcpu; 671 672 kvm_for_each_vcpu(i, vcpu, kvm) { 673 vcpu->arch.pause = false; 674 __kvm_vcpu_wake_up(vcpu); 675 } 676 } 677 678 static void kvm_vcpu_sleep(struct kvm_vcpu *vcpu) 679 { 680 struct rcuwait *wait = kvm_arch_vcpu_get_wait(vcpu); 681 682 rcuwait_wait_event(wait, 683 (!kvm_arm_vcpu_stopped(vcpu)) && (!vcpu->arch.pause), 684 TASK_INTERRUPTIBLE); 685 686 if (kvm_arm_vcpu_stopped(vcpu) || vcpu->arch.pause) { 687 /* Awaken to handle a signal, request we sleep again later. */ 688 kvm_make_request(KVM_REQ_SLEEP, vcpu); 689 } 690 691 /* 692 * Make sure we will observe a potential reset request if we've 693 * observed a change to the power state. Pairs with the smp_wmb() in 694 * kvm_psci_vcpu_on(). 695 */ 696 smp_rmb(); 697 } 698 699 /** 700 * kvm_vcpu_wfi - emulate Wait-For-Interrupt behavior 701 * @vcpu: The VCPU pointer 702 * 703 * Suspend execution of a vCPU until a valid wake event is detected, i.e. until 704 * the vCPU is runnable. The vCPU may or may not be scheduled out, depending 705 * on when a wake event arrives, e.g. there may already be a pending wake event. 706 */ 707 void kvm_vcpu_wfi(struct kvm_vcpu *vcpu) 708 { 709 /* 710 * Sync back the state of the GIC CPU interface so that we have 711 * the latest PMR and group enables. This ensures that 712 * kvm_arch_vcpu_runnable has up-to-date data to decide whether 713 * we have pending interrupts, e.g. when determining if the 714 * vCPU should block. 715 * 716 * For the same reason, we want to tell GICv4 that we need 717 * doorbells to be signalled, should an interrupt become pending. 718 */ 719 preempt_disable(); 720 kvm_vgic_vmcr_sync(vcpu); 721 vcpu_set_flag(vcpu, IN_WFI); 722 vgic_v4_put(vcpu); 723 preempt_enable(); 724 725 kvm_vcpu_halt(vcpu); 726 vcpu_clear_flag(vcpu, IN_WFIT); 727 728 preempt_disable(); 729 vcpu_clear_flag(vcpu, IN_WFI); 730 vgic_v4_load(vcpu); 731 preempt_enable(); 732 } 733 734 static int kvm_vcpu_suspend(struct kvm_vcpu *vcpu) 735 { 736 if (!kvm_arm_vcpu_suspended(vcpu)) 737 return 1; 738 739 kvm_vcpu_wfi(vcpu); 740 741 /* 742 * The suspend state is sticky; we do not leave it until userspace 743 * explicitly marks the vCPU as runnable. Request that we suspend again 744 * later. 745 */ 746 kvm_make_request(KVM_REQ_SUSPEND, vcpu); 747 748 /* 749 * Check to make sure the vCPU is actually runnable. If so, exit to 750 * userspace informing it of the wakeup condition. 751 */ 752 if (kvm_arch_vcpu_runnable(vcpu)) { 753 memset(&vcpu->run->system_event, 0, sizeof(vcpu->run->system_event)); 754 vcpu->run->system_event.type = KVM_SYSTEM_EVENT_WAKEUP; 755 vcpu->run->exit_reason = KVM_EXIT_SYSTEM_EVENT; 756 return 0; 757 } 758 759 /* 760 * Otherwise, we were unblocked to process a different event, such as a 761 * pending signal. Return 1 and allow kvm_arch_vcpu_ioctl_run() to 762 * process the event. 763 */ 764 return 1; 765 } 766 767 /** 768 * check_vcpu_requests - check and handle pending vCPU requests 769 * @vcpu: the VCPU pointer 770 * 771 * Return: 1 if we should enter the guest 772 * 0 if we should exit to userspace 773 * < 0 if we should exit to userspace, where the return value indicates 774 * an error 775 */ 776 static int check_vcpu_requests(struct kvm_vcpu *vcpu) 777 { 778 if (kvm_request_pending(vcpu)) { 779 if (kvm_check_request(KVM_REQ_SLEEP, vcpu)) 780 kvm_vcpu_sleep(vcpu); 781 782 if (kvm_check_request(KVM_REQ_VCPU_RESET, vcpu)) 783 kvm_reset_vcpu(vcpu); 784 785 /* 786 * Clear IRQ_PENDING requests that were made to guarantee 787 * that a VCPU sees new virtual interrupts. 788 */ 789 kvm_check_request(KVM_REQ_IRQ_PENDING, vcpu); 790 791 if (kvm_check_request(KVM_REQ_RECORD_STEAL, vcpu)) 792 kvm_update_stolen_time(vcpu); 793 794 if (kvm_check_request(KVM_REQ_RELOAD_GICv4, vcpu)) { 795 /* The distributor enable bits were changed */ 796 preempt_disable(); 797 vgic_v4_put(vcpu); 798 vgic_v4_load(vcpu); 799 preempt_enable(); 800 } 801 802 if (kvm_check_request(KVM_REQ_RELOAD_PMU, vcpu)) 803 kvm_pmu_handle_pmcr(vcpu, 804 __vcpu_sys_reg(vcpu, PMCR_EL0)); 805 806 if (kvm_check_request(KVM_REQ_SUSPEND, vcpu)) 807 return kvm_vcpu_suspend(vcpu); 808 809 if (kvm_dirty_ring_check_request(vcpu)) 810 return 0; 811 } 812 813 return 1; 814 } 815 816 static bool vcpu_mode_is_bad_32bit(struct kvm_vcpu *vcpu) 817 { 818 if (likely(!vcpu_mode_is_32bit(vcpu))) 819 return false; 820 821 return !kvm_supports_32bit_el0(); 822 } 823 824 /** 825 * kvm_vcpu_exit_request - returns true if the VCPU should *not* enter the guest 826 * @vcpu: The VCPU pointer 827 * @ret: Pointer to write optional return code 828 * 829 * Returns: true if the VCPU needs to return to a preemptible + interruptible 830 * and skip guest entry. 831 * 832 * This function disambiguates between two different types of exits: exits to a 833 * preemptible + interruptible kernel context and exits to userspace. For an 834 * exit to userspace, this function will write the return code to ret and return 835 * true. For an exit to preemptible + interruptible kernel context (i.e. check 836 * for pending work and re-enter), return true without writing to ret. 837 */ 838 static bool kvm_vcpu_exit_request(struct kvm_vcpu *vcpu, int *ret) 839 { 840 struct kvm_run *run = vcpu->run; 841 842 /* 843 * If we're using a userspace irqchip, then check if we need 844 * to tell a userspace irqchip about timer or PMU level 845 * changes and if so, exit to userspace (the actual level 846 * state gets updated in kvm_timer_update_run and 847 * kvm_pmu_update_run below). 848 */ 849 if (static_branch_unlikely(&userspace_irqchip_in_use)) { 850 if (kvm_timer_should_notify_user(vcpu) || 851 kvm_pmu_should_notify_user(vcpu)) { 852 *ret = -EINTR; 853 run->exit_reason = KVM_EXIT_INTR; 854 return true; 855 } 856 } 857 858 if (unlikely(vcpu_on_unsupported_cpu(vcpu))) { 859 run->exit_reason = KVM_EXIT_FAIL_ENTRY; 860 run->fail_entry.hardware_entry_failure_reason = KVM_EXIT_FAIL_ENTRY_CPU_UNSUPPORTED; 861 run->fail_entry.cpu = smp_processor_id(); 862 *ret = 0; 863 return true; 864 } 865 866 return kvm_request_pending(vcpu) || 867 xfer_to_guest_mode_work_pending(); 868 } 869 870 /* 871 * Actually run the vCPU, entering an RCU extended quiescent state (EQS) while 872 * the vCPU is running. 873 * 874 * This must be noinstr as instrumentation may make use of RCU, and this is not 875 * safe during the EQS. 876 */ 877 static int noinstr kvm_arm_vcpu_enter_exit(struct kvm_vcpu *vcpu) 878 { 879 int ret; 880 881 guest_state_enter_irqoff(); 882 ret = kvm_call_hyp_ret(__kvm_vcpu_run, vcpu); 883 guest_state_exit_irqoff(); 884 885 return ret; 886 } 887 888 /** 889 * kvm_arch_vcpu_ioctl_run - the main VCPU run function to execute guest code 890 * @vcpu: The VCPU pointer 891 * 892 * This function is called through the VCPU_RUN ioctl called from user space. It 893 * will execute VM code in a loop until the time slice for the process is used 894 * or some emulation is needed from user space in which case the function will 895 * return with return value 0 and with the kvm_run structure filled in with the 896 * required data for the requested emulation. 897 */ 898 int kvm_arch_vcpu_ioctl_run(struct kvm_vcpu *vcpu) 899 { 900 struct kvm_run *run = vcpu->run; 901 int ret; 902 903 if (run->exit_reason == KVM_EXIT_MMIO) { 904 ret = kvm_handle_mmio_return(vcpu); 905 if (ret) 906 return ret; 907 } 908 909 vcpu_load(vcpu); 910 911 if (run->immediate_exit) { 912 ret = -EINTR; 913 goto out; 914 } 915 916 kvm_sigset_activate(vcpu); 917 918 ret = 1; 919 run->exit_reason = KVM_EXIT_UNKNOWN; 920 run->flags = 0; 921 while (ret > 0) { 922 /* 923 * Check conditions before entering the guest 924 */ 925 ret = xfer_to_guest_mode_handle_work(vcpu); 926 if (!ret) 927 ret = 1; 928 929 if (ret > 0) 930 ret = check_vcpu_requests(vcpu); 931 932 /* 933 * Preparing the interrupts to be injected also 934 * involves poking the GIC, which must be done in a 935 * non-preemptible context. 936 */ 937 preempt_disable(); 938 939 /* 940 * The VMID allocator only tracks active VMIDs per 941 * physical CPU, and therefore the VMID allocated may not be 942 * preserved on VMID roll-over if the task was preempted, 943 * making a thread's VMID inactive. So we need to call 944 * kvm_arm_vmid_update() in non-premptible context. 945 */ 946 kvm_arm_vmid_update(&vcpu->arch.hw_mmu->vmid); 947 948 kvm_pmu_flush_hwstate(vcpu); 949 950 local_irq_disable(); 951 952 kvm_vgic_flush_hwstate(vcpu); 953 954 kvm_pmu_update_vcpu_events(vcpu); 955 956 /* 957 * Ensure we set mode to IN_GUEST_MODE after we disable 958 * interrupts and before the final VCPU requests check. 959 * See the comment in kvm_vcpu_exiting_guest_mode() and 960 * Documentation/virt/kvm/vcpu-requests.rst 961 */ 962 smp_store_mb(vcpu->mode, IN_GUEST_MODE); 963 964 if (ret <= 0 || kvm_vcpu_exit_request(vcpu, &ret)) { 965 vcpu->mode = OUTSIDE_GUEST_MODE; 966 isb(); /* Ensure work in x_flush_hwstate is committed */ 967 kvm_pmu_sync_hwstate(vcpu); 968 if (static_branch_unlikely(&userspace_irqchip_in_use)) 969 kvm_timer_sync_user(vcpu); 970 kvm_vgic_sync_hwstate(vcpu); 971 local_irq_enable(); 972 preempt_enable(); 973 continue; 974 } 975 976 kvm_arm_setup_debug(vcpu); 977 kvm_arch_vcpu_ctxflush_fp(vcpu); 978 979 /************************************************************** 980 * Enter the guest 981 */ 982 trace_kvm_entry(*vcpu_pc(vcpu)); 983 guest_timing_enter_irqoff(); 984 985 ret = kvm_arm_vcpu_enter_exit(vcpu); 986 987 vcpu->mode = OUTSIDE_GUEST_MODE; 988 vcpu->stat.exits++; 989 /* 990 * Back from guest 991 *************************************************************/ 992 993 kvm_arm_clear_debug(vcpu); 994 995 /* 996 * We must sync the PMU state before the vgic state so 997 * that the vgic can properly sample the updated state of the 998 * interrupt line. 999 */ 1000 kvm_pmu_sync_hwstate(vcpu); 1001 1002 /* 1003 * Sync the vgic state before syncing the timer state because 1004 * the timer code needs to know if the virtual timer 1005 * interrupts are active. 1006 */ 1007 kvm_vgic_sync_hwstate(vcpu); 1008 1009 /* 1010 * Sync the timer hardware state before enabling interrupts as 1011 * we don't want vtimer interrupts to race with syncing the 1012 * timer virtual interrupt state. 1013 */ 1014 if (static_branch_unlikely(&userspace_irqchip_in_use)) 1015 kvm_timer_sync_user(vcpu); 1016 1017 kvm_arch_vcpu_ctxsync_fp(vcpu); 1018 1019 /* 1020 * We must ensure that any pending interrupts are taken before 1021 * we exit guest timing so that timer ticks are accounted as 1022 * guest time. Transiently unmask interrupts so that any 1023 * pending interrupts are taken. 1024 * 1025 * Per ARM DDI 0487G.b section D1.13.4, an ISB (or other 1026 * context synchronization event) is necessary to ensure that 1027 * pending interrupts are taken. 1028 */ 1029 if (ARM_EXCEPTION_CODE(ret) == ARM_EXCEPTION_IRQ) { 1030 local_irq_enable(); 1031 isb(); 1032 local_irq_disable(); 1033 } 1034 1035 guest_timing_exit_irqoff(); 1036 1037 local_irq_enable(); 1038 1039 trace_kvm_exit(ret, kvm_vcpu_trap_get_class(vcpu), *vcpu_pc(vcpu)); 1040 1041 /* Exit types that need handling before we can be preempted */ 1042 handle_exit_early(vcpu, ret); 1043 1044 preempt_enable(); 1045 1046 /* 1047 * The ARMv8 architecture doesn't give the hypervisor 1048 * a mechanism to prevent a guest from dropping to AArch32 EL0 1049 * if implemented by the CPU. If we spot the guest in such 1050 * state and that we decided it wasn't supposed to do so (like 1051 * with the asymmetric AArch32 case), return to userspace with 1052 * a fatal error. 1053 */ 1054 if (vcpu_mode_is_bad_32bit(vcpu)) { 1055 /* 1056 * As we have caught the guest red-handed, decide that 1057 * it isn't fit for purpose anymore by making the vcpu 1058 * invalid. The VMM can try and fix it by issuing a 1059 * KVM_ARM_VCPU_INIT if it really wants to. 1060 */ 1061 vcpu->arch.target = -1; 1062 ret = ARM_EXCEPTION_IL; 1063 } 1064 1065 ret = handle_exit(vcpu, ret); 1066 } 1067 1068 /* Tell userspace about in-kernel device output levels */ 1069 if (unlikely(!irqchip_in_kernel(vcpu->kvm))) { 1070 kvm_timer_update_run(vcpu); 1071 kvm_pmu_update_run(vcpu); 1072 } 1073 1074 kvm_sigset_deactivate(vcpu); 1075 1076 out: 1077 /* 1078 * In the unlikely event that we are returning to userspace 1079 * with pending exceptions or PC adjustment, commit these 1080 * adjustments in order to give userspace a consistent view of 1081 * the vcpu state. Note that this relies on __kvm_adjust_pc() 1082 * being preempt-safe on VHE. 1083 */ 1084 if (unlikely(vcpu_get_flag(vcpu, PENDING_EXCEPTION) || 1085 vcpu_get_flag(vcpu, INCREMENT_PC))) 1086 kvm_call_hyp(__kvm_adjust_pc, vcpu); 1087 1088 vcpu_put(vcpu); 1089 return ret; 1090 } 1091 1092 static int vcpu_interrupt_line(struct kvm_vcpu *vcpu, int number, bool level) 1093 { 1094 int bit_index; 1095 bool set; 1096 unsigned long *hcr; 1097 1098 if (number == KVM_ARM_IRQ_CPU_IRQ) 1099 bit_index = __ffs(HCR_VI); 1100 else /* KVM_ARM_IRQ_CPU_FIQ */ 1101 bit_index = __ffs(HCR_VF); 1102 1103 hcr = vcpu_hcr(vcpu); 1104 if (level) 1105 set = test_and_set_bit(bit_index, hcr); 1106 else 1107 set = test_and_clear_bit(bit_index, hcr); 1108 1109 /* 1110 * If we didn't change anything, no need to wake up or kick other CPUs 1111 */ 1112 if (set == level) 1113 return 0; 1114 1115 /* 1116 * The vcpu irq_lines field was updated, wake up sleeping VCPUs and 1117 * trigger a world-switch round on the running physical CPU to set the 1118 * virtual IRQ/FIQ fields in the HCR appropriately. 1119 */ 1120 kvm_make_request(KVM_REQ_IRQ_PENDING, vcpu); 1121 kvm_vcpu_kick(vcpu); 1122 1123 return 0; 1124 } 1125 1126 int kvm_vm_ioctl_irq_line(struct kvm *kvm, struct kvm_irq_level *irq_level, 1127 bool line_status) 1128 { 1129 u32 irq = irq_level->irq; 1130 unsigned int irq_type, vcpu_idx, irq_num; 1131 int nrcpus = atomic_read(&kvm->online_vcpus); 1132 struct kvm_vcpu *vcpu = NULL; 1133 bool level = irq_level->level; 1134 1135 irq_type = (irq >> KVM_ARM_IRQ_TYPE_SHIFT) & KVM_ARM_IRQ_TYPE_MASK; 1136 vcpu_idx = (irq >> KVM_ARM_IRQ_VCPU_SHIFT) & KVM_ARM_IRQ_VCPU_MASK; 1137 vcpu_idx += ((irq >> KVM_ARM_IRQ_VCPU2_SHIFT) & KVM_ARM_IRQ_VCPU2_MASK) * (KVM_ARM_IRQ_VCPU_MASK + 1); 1138 irq_num = (irq >> KVM_ARM_IRQ_NUM_SHIFT) & KVM_ARM_IRQ_NUM_MASK; 1139 1140 trace_kvm_irq_line(irq_type, vcpu_idx, irq_num, irq_level->level); 1141 1142 switch (irq_type) { 1143 case KVM_ARM_IRQ_TYPE_CPU: 1144 if (irqchip_in_kernel(kvm)) 1145 return -ENXIO; 1146 1147 if (vcpu_idx >= nrcpus) 1148 return -EINVAL; 1149 1150 vcpu = kvm_get_vcpu(kvm, vcpu_idx); 1151 if (!vcpu) 1152 return -EINVAL; 1153 1154 if (irq_num > KVM_ARM_IRQ_CPU_FIQ) 1155 return -EINVAL; 1156 1157 return vcpu_interrupt_line(vcpu, irq_num, level); 1158 case KVM_ARM_IRQ_TYPE_PPI: 1159 if (!irqchip_in_kernel(kvm)) 1160 return -ENXIO; 1161 1162 if (vcpu_idx >= nrcpus) 1163 return -EINVAL; 1164 1165 vcpu = kvm_get_vcpu(kvm, vcpu_idx); 1166 if (!vcpu) 1167 return -EINVAL; 1168 1169 if (irq_num < VGIC_NR_SGIS || irq_num >= VGIC_NR_PRIVATE_IRQS) 1170 return -EINVAL; 1171 1172 return kvm_vgic_inject_irq(kvm, vcpu->vcpu_id, irq_num, level, NULL); 1173 case KVM_ARM_IRQ_TYPE_SPI: 1174 if (!irqchip_in_kernel(kvm)) 1175 return -ENXIO; 1176 1177 if (irq_num < VGIC_NR_PRIVATE_IRQS) 1178 return -EINVAL; 1179 1180 return kvm_vgic_inject_irq(kvm, 0, irq_num, level, NULL); 1181 } 1182 1183 return -EINVAL; 1184 } 1185 1186 static int kvm_vcpu_init_check_features(struct kvm_vcpu *vcpu, 1187 const struct kvm_vcpu_init *init) 1188 { 1189 unsigned long features = init->features[0]; 1190 int i; 1191 1192 if (features & ~KVM_VCPU_VALID_FEATURES) 1193 return -ENOENT; 1194 1195 for (i = 1; i < ARRAY_SIZE(init->features); i++) { 1196 if (init->features[i]) 1197 return -ENOENT; 1198 } 1199 1200 if (!test_bit(KVM_ARM_VCPU_EL1_32BIT, &features)) 1201 return 0; 1202 1203 if (!cpus_have_const_cap(ARM64_HAS_32BIT_EL1)) 1204 return -EINVAL; 1205 1206 /* MTE is incompatible with AArch32 */ 1207 if (kvm_has_mte(vcpu->kvm)) 1208 return -EINVAL; 1209 1210 /* NV is incompatible with AArch32 */ 1211 if (test_bit(KVM_ARM_VCPU_HAS_EL2, &features)) 1212 return -EINVAL; 1213 1214 return 0; 1215 } 1216 1217 static bool kvm_vcpu_init_changed(struct kvm_vcpu *vcpu, 1218 const struct kvm_vcpu_init *init) 1219 { 1220 unsigned long features = init->features[0]; 1221 1222 return !bitmap_equal(vcpu->arch.features, &features, KVM_VCPU_MAX_FEATURES) || 1223 vcpu->arch.target != init->target; 1224 } 1225 1226 static int __kvm_vcpu_set_target(struct kvm_vcpu *vcpu, 1227 const struct kvm_vcpu_init *init) 1228 { 1229 unsigned long features = init->features[0]; 1230 struct kvm *kvm = vcpu->kvm; 1231 int ret = -EINVAL; 1232 1233 mutex_lock(&kvm->arch.config_lock); 1234 1235 if (test_bit(KVM_ARCH_FLAG_VCPU_FEATURES_CONFIGURED, &kvm->arch.flags) && 1236 !bitmap_equal(kvm->arch.vcpu_features, &features, KVM_VCPU_MAX_FEATURES)) 1237 goto out_unlock; 1238 1239 vcpu->arch.target = init->target; 1240 bitmap_copy(vcpu->arch.features, &features, KVM_VCPU_MAX_FEATURES); 1241 1242 /* Now we know what it is, we can reset it. */ 1243 ret = kvm_reset_vcpu(vcpu); 1244 if (ret) { 1245 vcpu->arch.target = -1; 1246 bitmap_zero(vcpu->arch.features, KVM_VCPU_MAX_FEATURES); 1247 goto out_unlock; 1248 } 1249 1250 bitmap_copy(kvm->arch.vcpu_features, &features, KVM_VCPU_MAX_FEATURES); 1251 set_bit(KVM_ARCH_FLAG_VCPU_FEATURES_CONFIGURED, &kvm->arch.flags); 1252 1253 out_unlock: 1254 mutex_unlock(&kvm->arch.config_lock); 1255 return ret; 1256 } 1257 1258 static int kvm_vcpu_set_target(struct kvm_vcpu *vcpu, 1259 const struct kvm_vcpu_init *init) 1260 { 1261 int ret; 1262 1263 if (init->target != kvm_target_cpu()) 1264 return -EINVAL; 1265 1266 ret = kvm_vcpu_init_check_features(vcpu, init); 1267 if (ret) 1268 return ret; 1269 1270 if (vcpu->arch.target == -1) 1271 return __kvm_vcpu_set_target(vcpu, init); 1272 1273 if (kvm_vcpu_init_changed(vcpu, init)) 1274 return -EINVAL; 1275 1276 return kvm_reset_vcpu(vcpu); 1277 } 1278 1279 static int kvm_arch_vcpu_ioctl_vcpu_init(struct kvm_vcpu *vcpu, 1280 struct kvm_vcpu_init *init) 1281 { 1282 bool power_off = false; 1283 int ret; 1284 1285 /* 1286 * Treat the power-off vCPU feature as ephemeral. Clear the bit to avoid 1287 * reflecting it in the finalized feature set, thus limiting its scope 1288 * to a single KVM_ARM_VCPU_INIT call. 1289 */ 1290 if (init->features[0] & BIT(KVM_ARM_VCPU_POWER_OFF)) { 1291 init->features[0] &= ~BIT(KVM_ARM_VCPU_POWER_OFF); 1292 power_off = true; 1293 } 1294 1295 ret = kvm_vcpu_set_target(vcpu, init); 1296 if (ret) 1297 return ret; 1298 1299 /* 1300 * Ensure a rebooted VM will fault in RAM pages and detect if the 1301 * guest MMU is turned off and flush the caches as needed. 1302 * 1303 * S2FWB enforces all memory accesses to RAM being cacheable, 1304 * ensuring that the data side is always coherent. We still 1305 * need to invalidate the I-cache though, as FWB does *not* 1306 * imply CTR_EL0.DIC. 1307 */ 1308 if (vcpu_has_run_once(vcpu)) { 1309 if (!cpus_have_final_cap(ARM64_HAS_STAGE2_FWB)) 1310 stage2_unmap_vm(vcpu->kvm); 1311 else 1312 icache_inval_all_pou(); 1313 } 1314 1315 vcpu_reset_hcr(vcpu); 1316 vcpu->arch.cptr_el2 = kvm_get_reset_cptr_el2(vcpu); 1317 1318 /* 1319 * Handle the "start in power-off" case. 1320 */ 1321 spin_lock(&vcpu->arch.mp_state_lock); 1322 1323 if (power_off) 1324 __kvm_arm_vcpu_power_off(vcpu); 1325 else 1326 WRITE_ONCE(vcpu->arch.mp_state.mp_state, KVM_MP_STATE_RUNNABLE); 1327 1328 spin_unlock(&vcpu->arch.mp_state_lock); 1329 1330 return 0; 1331 } 1332 1333 static int kvm_arm_vcpu_set_attr(struct kvm_vcpu *vcpu, 1334 struct kvm_device_attr *attr) 1335 { 1336 int ret = -ENXIO; 1337 1338 switch (attr->group) { 1339 default: 1340 ret = kvm_arm_vcpu_arch_set_attr(vcpu, attr); 1341 break; 1342 } 1343 1344 return ret; 1345 } 1346 1347 static int kvm_arm_vcpu_get_attr(struct kvm_vcpu *vcpu, 1348 struct kvm_device_attr *attr) 1349 { 1350 int ret = -ENXIO; 1351 1352 switch (attr->group) { 1353 default: 1354 ret = kvm_arm_vcpu_arch_get_attr(vcpu, attr); 1355 break; 1356 } 1357 1358 return ret; 1359 } 1360 1361 static int kvm_arm_vcpu_has_attr(struct kvm_vcpu *vcpu, 1362 struct kvm_device_attr *attr) 1363 { 1364 int ret = -ENXIO; 1365 1366 switch (attr->group) { 1367 default: 1368 ret = kvm_arm_vcpu_arch_has_attr(vcpu, attr); 1369 break; 1370 } 1371 1372 return ret; 1373 } 1374 1375 static int kvm_arm_vcpu_get_events(struct kvm_vcpu *vcpu, 1376 struct kvm_vcpu_events *events) 1377 { 1378 memset(events, 0, sizeof(*events)); 1379 1380 return __kvm_arm_vcpu_get_events(vcpu, events); 1381 } 1382 1383 static int kvm_arm_vcpu_set_events(struct kvm_vcpu *vcpu, 1384 struct kvm_vcpu_events *events) 1385 { 1386 int i; 1387 1388 /* check whether the reserved field is zero */ 1389 for (i = 0; i < ARRAY_SIZE(events->reserved); i++) 1390 if (events->reserved[i]) 1391 return -EINVAL; 1392 1393 /* check whether the pad field is zero */ 1394 for (i = 0; i < ARRAY_SIZE(events->exception.pad); i++) 1395 if (events->exception.pad[i]) 1396 return -EINVAL; 1397 1398 return __kvm_arm_vcpu_set_events(vcpu, events); 1399 } 1400 1401 long kvm_arch_vcpu_ioctl(struct file *filp, 1402 unsigned int ioctl, unsigned long arg) 1403 { 1404 struct kvm_vcpu *vcpu = filp->private_data; 1405 void __user *argp = (void __user *)arg; 1406 struct kvm_device_attr attr; 1407 long r; 1408 1409 switch (ioctl) { 1410 case KVM_ARM_VCPU_INIT: { 1411 struct kvm_vcpu_init init; 1412 1413 r = -EFAULT; 1414 if (copy_from_user(&init, argp, sizeof(init))) 1415 break; 1416 1417 r = kvm_arch_vcpu_ioctl_vcpu_init(vcpu, &init); 1418 break; 1419 } 1420 case KVM_SET_ONE_REG: 1421 case KVM_GET_ONE_REG: { 1422 struct kvm_one_reg reg; 1423 1424 r = -ENOEXEC; 1425 if (unlikely(!kvm_vcpu_initialized(vcpu))) 1426 break; 1427 1428 r = -EFAULT; 1429 if (copy_from_user(®, argp, sizeof(reg))) 1430 break; 1431 1432 /* 1433 * We could owe a reset due to PSCI. Handle the pending reset 1434 * here to ensure userspace register accesses are ordered after 1435 * the reset. 1436 */ 1437 if (kvm_check_request(KVM_REQ_VCPU_RESET, vcpu)) 1438 kvm_reset_vcpu(vcpu); 1439 1440 if (ioctl == KVM_SET_ONE_REG) 1441 r = kvm_arm_set_reg(vcpu, ®); 1442 else 1443 r = kvm_arm_get_reg(vcpu, ®); 1444 break; 1445 } 1446 case KVM_GET_REG_LIST: { 1447 struct kvm_reg_list __user *user_list = argp; 1448 struct kvm_reg_list reg_list; 1449 unsigned n; 1450 1451 r = -ENOEXEC; 1452 if (unlikely(!kvm_vcpu_initialized(vcpu))) 1453 break; 1454 1455 r = -EPERM; 1456 if (!kvm_arm_vcpu_is_finalized(vcpu)) 1457 break; 1458 1459 r = -EFAULT; 1460 if (copy_from_user(®_list, user_list, sizeof(reg_list))) 1461 break; 1462 n = reg_list.n; 1463 reg_list.n = kvm_arm_num_regs(vcpu); 1464 if (copy_to_user(user_list, ®_list, sizeof(reg_list))) 1465 break; 1466 r = -E2BIG; 1467 if (n < reg_list.n) 1468 break; 1469 r = kvm_arm_copy_reg_indices(vcpu, user_list->reg); 1470 break; 1471 } 1472 case KVM_SET_DEVICE_ATTR: { 1473 r = -EFAULT; 1474 if (copy_from_user(&attr, argp, sizeof(attr))) 1475 break; 1476 r = kvm_arm_vcpu_set_attr(vcpu, &attr); 1477 break; 1478 } 1479 case KVM_GET_DEVICE_ATTR: { 1480 r = -EFAULT; 1481 if (copy_from_user(&attr, argp, sizeof(attr))) 1482 break; 1483 r = kvm_arm_vcpu_get_attr(vcpu, &attr); 1484 break; 1485 } 1486 case KVM_HAS_DEVICE_ATTR: { 1487 r = -EFAULT; 1488 if (copy_from_user(&attr, argp, sizeof(attr))) 1489 break; 1490 r = kvm_arm_vcpu_has_attr(vcpu, &attr); 1491 break; 1492 } 1493 case KVM_GET_VCPU_EVENTS: { 1494 struct kvm_vcpu_events events; 1495 1496 if (kvm_arm_vcpu_get_events(vcpu, &events)) 1497 return -EINVAL; 1498 1499 if (copy_to_user(argp, &events, sizeof(events))) 1500 return -EFAULT; 1501 1502 return 0; 1503 } 1504 case KVM_SET_VCPU_EVENTS: { 1505 struct kvm_vcpu_events events; 1506 1507 if (copy_from_user(&events, argp, sizeof(events))) 1508 return -EFAULT; 1509 1510 return kvm_arm_vcpu_set_events(vcpu, &events); 1511 } 1512 case KVM_ARM_VCPU_FINALIZE: { 1513 int what; 1514 1515 if (!kvm_vcpu_initialized(vcpu)) 1516 return -ENOEXEC; 1517 1518 if (get_user(what, (const int __user *)argp)) 1519 return -EFAULT; 1520 1521 return kvm_arm_vcpu_finalize(vcpu, what); 1522 } 1523 default: 1524 r = -EINVAL; 1525 } 1526 1527 return r; 1528 } 1529 1530 void kvm_arch_sync_dirty_log(struct kvm *kvm, struct kvm_memory_slot *memslot) 1531 { 1532 1533 } 1534 1535 static int kvm_vm_ioctl_set_device_addr(struct kvm *kvm, 1536 struct kvm_arm_device_addr *dev_addr) 1537 { 1538 switch (FIELD_GET(KVM_ARM_DEVICE_ID_MASK, dev_addr->id)) { 1539 case KVM_ARM_DEVICE_VGIC_V2: 1540 if (!vgic_present) 1541 return -ENXIO; 1542 return kvm_set_legacy_vgic_v2_addr(kvm, dev_addr); 1543 default: 1544 return -ENODEV; 1545 } 1546 } 1547 1548 static int kvm_vm_has_attr(struct kvm *kvm, struct kvm_device_attr *attr) 1549 { 1550 switch (attr->group) { 1551 case KVM_ARM_VM_SMCCC_CTRL: 1552 return kvm_vm_smccc_has_attr(kvm, attr); 1553 default: 1554 return -ENXIO; 1555 } 1556 } 1557 1558 static int kvm_vm_set_attr(struct kvm *kvm, struct kvm_device_attr *attr) 1559 { 1560 switch (attr->group) { 1561 case KVM_ARM_VM_SMCCC_CTRL: 1562 return kvm_vm_smccc_set_attr(kvm, attr); 1563 default: 1564 return -ENXIO; 1565 } 1566 } 1567 1568 int kvm_arch_vm_ioctl(struct file *filp, unsigned int ioctl, unsigned long arg) 1569 { 1570 struct kvm *kvm = filp->private_data; 1571 void __user *argp = (void __user *)arg; 1572 struct kvm_device_attr attr; 1573 1574 switch (ioctl) { 1575 case KVM_CREATE_IRQCHIP: { 1576 int ret; 1577 if (!vgic_present) 1578 return -ENXIO; 1579 mutex_lock(&kvm->lock); 1580 ret = kvm_vgic_create(kvm, KVM_DEV_TYPE_ARM_VGIC_V2); 1581 mutex_unlock(&kvm->lock); 1582 return ret; 1583 } 1584 case KVM_ARM_SET_DEVICE_ADDR: { 1585 struct kvm_arm_device_addr dev_addr; 1586 1587 if (copy_from_user(&dev_addr, argp, sizeof(dev_addr))) 1588 return -EFAULT; 1589 return kvm_vm_ioctl_set_device_addr(kvm, &dev_addr); 1590 } 1591 case KVM_ARM_PREFERRED_TARGET: { 1592 struct kvm_vcpu_init init; 1593 1594 kvm_vcpu_preferred_target(&init); 1595 1596 if (copy_to_user(argp, &init, sizeof(init))) 1597 return -EFAULT; 1598 1599 return 0; 1600 } 1601 case KVM_ARM_MTE_COPY_TAGS: { 1602 struct kvm_arm_copy_mte_tags copy_tags; 1603 1604 if (copy_from_user(©_tags, argp, sizeof(copy_tags))) 1605 return -EFAULT; 1606 return kvm_vm_ioctl_mte_copy_tags(kvm, ©_tags); 1607 } 1608 case KVM_ARM_SET_COUNTER_OFFSET: { 1609 struct kvm_arm_counter_offset offset; 1610 1611 if (copy_from_user(&offset, argp, sizeof(offset))) 1612 return -EFAULT; 1613 return kvm_vm_ioctl_set_counter_offset(kvm, &offset); 1614 } 1615 case KVM_HAS_DEVICE_ATTR: { 1616 if (copy_from_user(&attr, argp, sizeof(attr))) 1617 return -EFAULT; 1618 1619 return kvm_vm_has_attr(kvm, &attr); 1620 } 1621 case KVM_SET_DEVICE_ATTR: { 1622 if (copy_from_user(&attr, argp, sizeof(attr))) 1623 return -EFAULT; 1624 1625 return kvm_vm_set_attr(kvm, &attr); 1626 } 1627 default: 1628 return -EINVAL; 1629 } 1630 } 1631 1632 /* unlocks vcpus from @vcpu_lock_idx and smaller */ 1633 static void unlock_vcpus(struct kvm *kvm, int vcpu_lock_idx) 1634 { 1635 struct kvm_vcpu *tmp_vcpu; 1636 1637 for (; vcpu_lock_idx >= 0; vcpu_lock_idx--) { 1638 tmp_vcpu = kvm_get_vcpu(kvm, vcpu_lock_idx); 1639 mutex_unlock(&tmp_vcpu->mutex); 1640 } 1641 } 1642 1643 void unlock_all_vcpus(struct kvm *kvm) 1644 { 1645 lockdep_assert_held(&kvm->lock); 1646 1647 unlock_vcpus(kvm, atomic_read(&kvm->online_vcpus) - 1); 1648 } 1649 1650 /* Returns true if all vcpus were locked, false otherwise */ 1651 bool lock_all_vcpus(struct kvm *kvm) 1652 { 1653 struct kvm_vcpu *tmp_vcpu; 1654 unsigned long c; 1655 1656 lockdep_assert_held(&kvm->lock); 1657 1658 /* 1659 * Any time a vcpu is in an ioctl (including running), the 1660 * core KVM code tries to grab the vcpu->mutex. 1661 * 1662 * By grabbing the vcpu->mutex of all VCPUs we ensure that no 1663 * other VCPUs can fiddle with the state while we access it. 1664 */ 1665 kvm_for_each_vcpu(c, tmp_vcpu, kvm) { 1666 if (!mutex_trylock(&tmp_vcpu->mutex)) { 1667 unlock_vcpus(kvm, c - 1); 1668 return false; 1669 } 1670 } 1671 1672 return true; 1673 } 1674 1675 static unsigned long nvhe_percpu_size(void) 1676 { 1677 return (unsigned long)CHOOSE_NVHE_SYM(__per_cpu_end) - 1678 (unsigned long)CHOOSE_NVHE_SYM(__per_cpu_start); 1679 } 1680 1681 static unsigned long nvhe_percpu_order(void) 1682 { 1683 unsigned long size = nvhe_percpu_size(); 1684 1685 return size ? get_order(size) : 0; 1686 } 1687 1688 /* A lookup table holding the hypervisor VA for each vector slot */ 1689 static void *hyp_spectre_vector_selector[BP_HARDEN_EL2_SLOTS]; 1690 1691 static void kvm_init_vector_slot(void *base, enum arm64_hyp_spectre_vector slot) 1692 { 1693 hyp_spectre_vector_selector[slot] = __kvm_vector_slot2addr(base, slot); 1694 } 1695 1696 static int kvm_init_vector_slots(void) 1697 { 1698 int err; 1699 void *base; 1700 1701 base = kern_hyp_va(kvm_ksym_ref(__kvm_hyp_vector)); 1702 kvm_init_vector_slot(base, HYP_VECTOR_DIRECT); 1703 1704 base = kern_hyp_va(kvm_ksym_ref(__bp_harden_hyp_vecs)); 1705 kvm_init_vector_slot(base, HYP_VECTOR_SPECTRE_DIRECT); 1706 1707 if (kvm_system_needs_idmapped_vectors() && 1708 !is_protected_kvm_enabled()) { 1709 err = create_hyp_exec_mappings(__pa_symbol(__bp_harden_hyp_vecs), 1710 __BP_HARDEN_HYP_VECS_SZ, &base); 1711 if (err) 1712 return err; 1713 } 1714 1715 kvm_init_vector_slot(base, HYP_VECTOR_INDIRECT); 1716 kvm_init_vector_slot(base, HYP_VECTOR_SPECTRE_INDIRECT); 1717 return 0; 1718 } 1719 1720 static void __init cpu_prepare_hyp_mode(int cpu, u32 hyp_va_bits) 1721 { 1722 struct kvm_nvhe_init_params *params = per_cpu_ptr_nvhe_sym(kvm_init_params, cpu); 1723 unsigned long tcr; 1724 1725 /* 1726 * Calculate the raw per-cpu offset without a translation from the 1727 * kernel's mapping to the linear mapping, and store it in tpidr_el2 1728 * so that we can use adr_l to access per-cpu variables in EL2. 1729 * Also drop the KASAN tag which gets in the way... 1730 */ 1731 params->tpidr_el2 = (unsigned long)kasan_reset_tag(per_cpu_ptr_nvhe_sym(__per_cpu_start, cpu)) - 1732 (unsigned long)kvm_ksym_ref(CHOOSE_NVHE_SYM(__per_cpu_start)); 1733 1734 params->mair_el2 = read_sysreg(mair_el1); 1735 1736 tcr = read_sysreg(tcr_el1); 1737 if (cpus_have_final_cap(ARM64_KVM_HVHE)) { 1738 tcr |= TCR_EPD1_MASK; 1739 } else { 1740 tcr &= TCR_EL2_MASK; 1741 tcr |= TCR_EL2_RES1; 1742 } 1743 tcr &= ~TCR_T0SZ_MASK; 1744 tcr |= TCR_T0SZ(hyp_va_bits); 1745 params->tcr_el2 = tcr; 1746 1747 params->pgd_pa = kvm_mmu_get_httbr(); 1748 if (is_protected_kvm_enabled()) 1749 params->hcr_el2 = HCR_HOST_NVHE_PROTECTED_FLAGS; 1750 else 1751 params->hcr_el2 = HCR_HOST_NVHE_FLAGS; 1752 if (cpus_have_final_cap(ARM64_KVM_HVHE)) 1753 params->hcr_el2 |= HCR_E2H; 1754 params->vttbr = params->vtcr = 0; 1755 1756 /* 1757 * Flush the init params from the data cache because the struct will 1758 * be read while the MMU is off. 1759 */ 1760 kvm_flush_dcache_to_poc(params, sizeof(*params)); 1761 } 1762 1763 static void hyp_install_host_vector(void) 1764 { 1765 struct kvm_nvhe_init_params *params; 1766 struct arm_smccc_res res; 1767 1768 /* Switch from the HYP stub to our own HYP init vector */ 1769 __hyp_set_vectors(kvm_get_idmap_vector()); 1770 1771 /* 1772 * Call initialization code, and switch to the full blown HYP code. 1773 * If the cpucaps haven't been finalized yet, something has gone very 1774 * wrong, and hyp will crash and burn when it uses any 1775 * cpus_have_const_cap() wrapper. 1776 */ 1777 BUG_ON(!system_capabilities_finalized()); 1778 params = this_cpu_ptr_nvhe_sym(kvm_init_params); 1779 arm_smccc_1_1_hvc(KVM_HOST_SMCCC_FUNC(__kvm_hyp_init), virt_to_phys(params), &res); 1780 WARN_ON(res.a0 != SMCCC_RET_SUCCESS); 1781 } 1782 1783 static void cpu_init_hyp_mode(void) 1784 { 1785 hyp_install_host_vector(); 1786 1787 /* 1788 * Disabling SSBD on a non-VHE system requires us to enable SSBS 1789 * at EL2. 1790 */ 1791 if (this_cpu_has_cap(ARM64_SSBS) && 1792 arm64_get_spectre_v4_state() == SPECTRE_VULNERABLE) { 1793 kvm_call_hyp_nvhe(__kvm_enable_ssbs); 1794 } 1795 } 1796 1797 static void cpu_hyp_reset(void) 1798 { 1799 if (!is_kernel_in_hyp_mode()) 1800 __hyp_reset_vectors(); 1801 } 1802 1803 /* 1804 * EL2 vectors can be mapped and rerouted in a number of ways, 1805 * depending on the kernel configuration and CPU present: 1806 * 1807 * - If the CPU is affected by Spectre-v2, the hardening sequence is 1808 * placed in one of the vector slots, which is executed before jumping 1809 * to the real vectors. 1810 * 1811 * - If the CPU also has the ARM64_SPECTRE_V3A cap, the slot 1812 * containing the hardening sequence is mapped next to the idmap page, 1813 * and executed before jumping to the real vectors. 1814 * 1815 * - If the CPU only has the ARM64_SPECTRE_V3A cap, then an 1816 * empty slot is selected, mapped next to the idmap page, and 1817 * executed before jumping to the real vectors. 1818 * 1819 * Note that ARM64_SPECTRE_V3A is somewhat incompatible with 1820 * VHE, as we don't have hypervisor-specific mappings. If the system 1821 * is VHE and yet selects this capability, it will be ignored. 1822 */ 1823 static void cpu_set_hyp_vector(void) 1824 { 1825 struct bp_hardening_data *data = this_cpu_ptr(&bp_hardening_data); 1826 void *vector = hyp_spectre_vector_selector[data->slot]; 1827 1828 if (!is_protected_kvm_enabled()) 1829 *this_cpu_ptr_hyp_sym(kvm_hyp_vector) = (unsigned long)vector; 1830 else 1831 kvm_call_hyp_nvhe(__pkvm_cpu_set_vector, data->slot); 1832 } 1833 1834 static void cpu_hyp_init_context(void) 1835 { 1836 kvm_init_host_cpu_context(&this_cpu_ptr_hyp_sym(kvm_host_data)->host_ctxt); 1837 1838 if (!is_kernel_in_hyp_mode()) 1839 cpu_init_hyp_mode(); 1840 } 1841 1842 static void cpu_hyp_init_features(void) 1843 { 1844 cpu_set_hyp_vector(); 1845 kvm_arm_init_debug(); 1846 1847 if (is_kernel_in_hyp_mode()) 1848 kvm_timer_init_vhe(); 1849 1850 if (vgic_present) 1851 kvm_vgic_init_cpu_hardware(); 1852 } 1853 1854 static void cpu_hyp_reinit(void) 1855 { 1856 cpu_hyp_reset(); 1857 cpu_hyp_init_context(); 1858 cpu_hyp_init_features(); 1859 } 1860 1861 static void _kvm_arch_hardware_enable(void *discard) 1862 { 1863 if (!__this_cpu_read(kvm_arm_hardware_enabled)) { 1864 cpu_hyp_reinit(); 1865 __this_cpu_write(kvm_arm_hardware_enabled, 1); 1866 } 1867 } 1868 1869 int kvm_arch_hardware_enable(void) 1870 { 1871 int was_enabled; 1872 1873 /* 1874 * Most calls to this function are made with migration 1875 * disabled, but not with preemption disabled. The former is 1876 * enough to ensure correctness, but most of the helpers 1877 * expect the later and will throw a tantrum otherwise. 1878 */ 1879 preempt_disable(); 1880 1881 was_enabled = __this_cpu_read(kvm_arm_hardware_enabled); 1882 _kvm_arch_hardware_enable(NULL); 1883 1884 if (!was_enabled) { 1885 kvm_vgic_cpu_up(); 1886 kvm_timer_cpu_up(); 1887 } 1888 1889 preempt_enable(); 1890 1891 return 0; 1892 } 1893 1894 static void _kvm_arch_hardware_disable(void *discard) 1895 { 1896 if (__this_cpu_read(kvm_arm_hardware_enabled)) { 1897 cpu_hyp_reset(); 1898 __this_cpu_write(kvm_arm_hardware_enabled, 0); 1899 } 1900 } 1901 1902 void kvm_arch_hardware_disable(void) 1903 { 1904 if (__this_cpu_read(kvm_arm_hardware_enabled)) { 1905 kvm_timer_cpu_down(); 1906 kvm_vgic_cpu_down(); 1907 } 1908 1909 if (!is_protected_kvm_enabled()) 1910 _kvm_arch_hardware_disable(NULL); 1911 } 1912 1913 #ifdef CONFIG_CPU_PM 1914 static int hyp_init_cpu_pm_notifier(struct notifier_block *self, 1915 unsigned long cmd, 1916 void *v) 1917 { 1918 /* 1919 * kvm_arm_hardware_enabled is left with its old value over 1920 * PM_ENTER->PM_EXIT. It is used to indicate PM_EXIT should 1921 * re-enable hyp. 1922 */ 1923 switch (cmd) { 1924 case CPU_PM_ENTER: 1925 if (__this_cpu_read(kvm_arm_hardware_enabled)) 1926 /* 1927 * don't update kvm_arm_hardware_enabled here 1928 * so that the hardware will be re-enabled 1929 * when we resume. See below. 1930 */ 1931 cpu_hyp_reset(); 1932 1933 return NOTIFY_OK; 1934 case CPU_PM_ENTER_FAILED: 1935 case CPU_PM_EXIT: 1936 if (__this_cpu_read(kvm_arm_hardware_enabled)) 1937 /* The hardware was enabled before suspend. */ 1938 cpu_hyp_reinit(); 1939 1940 return NOTIFY_OK; 1941 1942 default: 1943 return NOTIFY_DONE; 1944 } 1945 } 1946 1947 static struct notifier_block hyp_init_cpu_pm_nb = { 1948 .notifier_call = hyp_init_cpu_pm_notifier, 1949 }; 1950 1951 static void __init hyp_cpu_pm_init(void) 1952 { 1953 if (!is_protected_kvm_enabled()) 1954 cpu_pm_register_notifier(&hyp_init_cpu_pm_nb); 1955 } 1956 static void __init hyp_cpu_pm_exit(void) 1957 { 1958 if (!is_protected_kvm_enabled()) 1959 cpu_pm_unregister_notifier(&hyp_init_cpu_pm_nb); 1960 } 1961 #else 1962 static inline void __init hyp_cpu_pm_init(void) 1963 { 1964 } 1965 static inline void __init hyp_cpu_pm_exit(void) 1966 { 1967 } 1968 #endif 1969 1970 static void __init init_cpu_logical_map(void) 1971 { 1972 unsigned int cpu; 1973 1974 /* 1975 * Copy the MPIDR <-> logical CPU ID mapping to hyp. 1976 * Only copy the set of online CPUs whose features have been checked 1977 * against the finalized system capabilities. The hypervisor will not 1978 * allow any other CPUs from the `possible` set to boot. 1979 */ 1980 for_each_online_cpu(cpu) 1981 hyp_cpu_logical_map[cpu] = cpu_logical_map(cpu); 1982 } 1983 1984 #define init_psci_0_1_impl_state(config, what) \ 1985 config.psci_0_1_ ## what ## _implemented = psci_ops.what 1986 1987 static bool __init init_psci_relay(void) 1988 { 1989 /* 1990 * If PSCI has not been initialized, protected KVM cannot install 1991 * itself on newly booted CPUs. 1992 */ 1993 if (!psci_ops.get_version) { 1994 kvm_err("Cannot initialize protected mode without PSCI\n"); 1995 return false; 1996 } 1997 1998 kvm_host_psci_config.version = psci_ops.get_version(); 1999 kvm_host_psci_config.smccc_version = arm_smccc_get_version(); 2000 2001 if (kvm_host_psci_config.version == PSCI_VERSION(0, 1)) { 2002 kvm_host_psci_config.function_ids_0_1 = get_psci_0_1_function_ids(); 2003 init_psci_0_1_impl_state(kvm_host_psci_config, cpu_suspend); 2004 init_psci_0_1_impl_state(kvm_host_psci_config, cpu_on); 2005 init_psci_0_1_impl_state(kvm_host_psci_config, cpu_off); 2006 init_psci_0_1_impl_state(kvm_host_psci_config, migrate); 2007 } 2008 return true; 2009 } 2010 2011 static int __init init_subsystems(void) 2012 { 2013 int err = 0; 2014 2015 /* 2016 * Enable hardware so that subsystem initialisation can access EL2. 2017 */ 2018 on_each_cpu(_kvm_arch_hardware_enable, NULL, 1); 2019 2020 /* 2021 * Register CPU lower-power notifier 2022 */ 2023 hyp_cpu_pm_init(); 2024 2025 /* 2026 * Init HYP view of VGIC 2027 */ 2028 err = kvm_vgic_hyp_init(); 2029 switch (err) { 2030 case 0: 2031 vgic_present = true; 2032 break; 2033 case -ENODEV: 2034 case -ENXIO: 2035 vgic_present = false; 2036 err = 0; 2037 break; 2038 default: 2039 goto out; 2040 } 2041 2042 /* 2043 * Init HYP architected timer support 2044 */ 2045 err = kvm_timer_hyp_init(vgic_present); 2046 if (err) 2047 goto out; 2048 2049 kvm_register_perf_callbacks(NULL); 2050 2051 out: 2052 if (err) 2053 hyp_cpu_pm_exit(); 2054 2055 if (err || !is_protected_kvm_enabled()) 2056 on_each_cpu(_kvm_arch_hardware_disable, NULL, 1); 2057 2058 return err; 2059 } 2060 2061 static void __init teardown_subsystems(void) 2062 { 2063 kvm_unregister_perf_callbacks(); 2064 hyp_cpu_pm_exit(); 2065 } 2066 2067 static void __init teardown_hyp_mode(void) 2068 { 2069 int cpu; 2070 2071 free_hyp_pgds(); 2072 for_each_possible_cpu(cpu) { 2073 free_page(per_cpu(kvm_arm_hyp_stack_page, cpu)); 2074 free_pages(kvm_nvhe_sym(kvm_arm_hyp_percpu_base)[cpu], nvhe_percpu_order()); 2075 } 2076 } 2077 2078 static int __init do_pkvm_init(u32 hyp_va_bits) 2079 { 2080 void *per_cpu_base = kvm_ksym_ref(kvm_nvhe_sym(kvm_arm_hyp_percpu_base)); 2081 int ret; 2082 2083 preempt_disable(); 2084 cpu_hyp_init_context(); 2085 ret = kvm_call_hyp_nvhe(__pkvm_init, hyp_mem_base, hyp_mem_size, 2086 num_possible_cpus(), kern_hyp_va(per_cpu_base), 2087 hyp_va_bits); 2088 cpu_hyp_init_features(); 2089 2090 /* 2091 * The stub hypercalls are now disabled, so set our local flag to 2092 * prevent a later re-init attempt in kvm_arch_hardware_enable(). 2093 */ 2094 __this_cpu_write(kvm_arm_hardware_enabled, 1); 2095 preempt_enable(); 2096 2097 return ret; 2098 } 2099 2100 static u64 get_hyp_id_aa64pfr0_el1(void) 2101 { 2102 /* 2103 * Track whether the system isn't affected by spectre/meltdown in the 2104 * hypervisor's view of id_aa64pfr0_el1, used for protected VMs. 2105 * Although this is per-CPU, we make it global for simplicity, e.g., not 2106 * to have to worry about vcpu migration. 2107 * 2108 * Unlike for non-protected VMs, userspace cannot override this for 2109 * protected VMs. 2110 */ 2111 u64 val = read_sanitised_ftr_reg(SYS_ID_AA64PFR0_EL1); 2112 2113 val &= ~(ARM64_FEATURE_MASK(ID_AA64PFR0_EL1_CSV2) | 2114 ARM64_FEATURE_MASK(ID_AA64PFR0_EL1_CSV3)); 2115 2116 val |= FIELD_PREP(ARM64_FEATURE_MASK(ID_AA64PFR0_EL1_CSV2), 2117 arm64_get_spectre_v2_state() == SPECTRE_UNAFFECTED); 2118 val |= FIELD_PREP(ARM64_FEATURE_MASK(ID_AA64PFR0_EL1_CSV3), 2119 arm64_get_meltdown_state() == SPECTRE_UNAFFECTED); 2120 2121 return val; 2122 } 2123 2124 static void kvm_hyp_init_symbols(void) 2125 { 2126 kvm_nvhe_sym(id_aa64pfr0_el1_sys_val) = get_hyp_id_aa64pfr0_el1(); 2127 kvm_nvhe_sym(id_aa64pfr1_el1_sys_val) = read_sanitised_ftr_reg(SYS_ID_AA64PFR1_EL1); 2128 kvm_nvhe_sym(id_aa64isar0_el1_sys_val) = read_sanitised_ftr_reg(SYS_ID_AA64ISAR0_EL1); 2129 kvm_nvhe_sym(id_aa64isar1_el1_sys_val) = read_sanitised_ftr_reg(SYS_ID_AA64ISAR1_EL1); 2130 kvm_nvhe_sym(id_aa64isar2_el1_sys_val) = read_sanitised_ftr_reg(SYS_ID_AA64ISAR2_EL1); 2131 kvm_nvhe_sym(id_aa64mmfr0_el1_sys_val) = read_sanitised_ftr_reg(SYS_ID_AA64MMFR0_EL1); 2132 kvm_nvhe_sym(id_aa64mmfr1_el1_sys_val) = read_sanitised_ftr_reg(SYS_ID_AA64MMFR1_EL1); 2133 kvm_nvhe_sym(id_aa64mmfr2_el1_sys_val) = read_sanitised_ftr_reg(SYS_ID_AA64MMFR2_EL1); 2134 kvm_nvhe_sym(id_aa64smfr0_el1_sys_val) = read_sanitised_ftr_reg(SYS_ID_AA64SMFR0_EL1); 2135 kvm_nvhe_sym(__icache_flags) = __icache_flags; 2136 kvm_nvhe_sym(kvm_arm_vmid_bits) = kvm_arm_vmid_bits; 2137 } 2138 2139 static int __init kvm_hyp_init_protection(u32 hyp_va_bits) 2140 { 2141 void *addr = phys_to_virt(hyp_mem_base); 2142 int ret; 2143 2144 ret = create_hyp_mappings(addr, addr + hyp_mem_size, PAGE_HYP); 2145 if (ret) 2146 return ret; 2147 2148 ret = do_pkvm_init(hyp_va_bits); 2149 if (ret) 2150 return ret; 2151 2152 free_hyp_pgds(); 2153 2154 return 0; 2155 } 2156 2157 static void pkvm_hyp_init_ptrauth(void) 2158 { 2159 struct kvm_cpu_context *hyp_ctxt; 2160 int cpu; 2161 2162 for_each_possible_cpu(cpu) { 2163 hyp_ctxt = per_cpu_ptr_nvhe_sym(kvm_hyp_ctxt, cpu); 2164 hyp_ctxt->sys_regs[APIAKEYLO_EL1] = get_random_long(); 2165 hyp_ctxt->sys_regs[APIAKEYHI_EL1] = get_random_long(); 2166 hyp_ctxt->sys_regs[APIBKEYLO_EL1] = get_random_long(); 2167 hyp_ctxt->sys_regs[APIBKEYHI_EL1] = get_random_long(); 2168 hyp_ctxt->sys_regs[APDAKEYLO_EL1] = get_random_long(); 2169 hyp_ctxt->sys_regs[APDAKEYHI_EL1] = get_random_long(); 2170 hyp_ctxt->sys_regs[APDBKEYLO_EL1] = get_random_long(); 2171 hyp_ctxt->sys_regs[APDBKEYHI_EL1] = get_random_long(); 2172 hyp_ctxt->sys_regs[APGAKEYLO_EL1] = get_random_long(); 2173 hyp_ctxt->sys_regs[APGAKEYHI_EL1] = get_random_long(); 2174 } 2175 } 2176 2177 /* Inits Hyp-mode on all online CPUs */ 2178 static int __init init_hyp_mode(void) 2179 { 2180 u32 hyp_va_bits; 2181 int cpu; 2182 int err = -ENOMEM; 2183 2184 /* 2185 * The protected Hyp-mode cannot be initialized if the memory pool 2186 * allocation has failed. 2187 */ 2188 if (is_protected_kvm_enabled() && !hyp_mem_base) 2189 goto out_err; 2190 2191 /* 2192 * Allocate Hyp PGD and setup Hyp identity mapping 2193 */ 2194 err = kvm_mmu_init(&hyp_va_bits); 2195 if (err) 2196 goto out_err; 2197 2198 /* 2199 * Allocate stack pages for Hypervisor-mode 2200 */ 2201 for_each_possible_cpu(cpu) { 2202 unsigned long stack_page; 2203 2204 stack_page = __get_free_page(GFP_KERNEL); 2205 if (!stack_page) { 2206 err = -ENOMEM; 2207 goto out_err; 2208 } 2209 2210 per_cpu(kvm_arm_hyp_stack_page, cpu) = stack_page; 2211 } 2212 2213 /* 2214 * Allocate and initialize pages for Hypervisor-mode percpu regions. 2215 */ 2216 for_each_possible_cpu(cpu) { 2217 struct page *page; 2218 void *page_addr; 2219 2220 page = alloc_pages(GFP_KERNEL, nvhe_percpu_order()); 2221 if (!page) { 2222 err = -ENOMEM; 2223 goto out_err; 2224 } 2225 2226 page_addr = page_address(page); 2227 memcpy(page_addr, CHOOSE_NVHE_SYM(__per_cpu_start), nvhe_percpu_size()); 2228 kvm_nvhe_sym(kvm_arm_hyp_percpu_base)[cpu] = (unsigned long)page_addr; 2229 } 2230 2231 /* 2232 * Map the Hyp-code called directly from the host 2233 */ 2234 err = create_hyp_mappings(kvm_ksym_ref(__hyp_text_start), 2235 kvm_ksym_ref(__hyp_text_end), PAGE_HYP_EXEC); 2236 if (err) { 2237 kvm_err("Cannot map world-switch code\n"); 2238 goto out_err; 2239 } 2240 2241 err = create_hyp_mappings(kvm_ksym_ref(__hyp_rodata_start), 2242 kvm_ksym_ref(__hyp_rodata_end), PAGE_HYP_RO); 2243 if (err) { 2244 kvm_err("Cannot map .hyp.rodata section\n"); 2245 goto out_err; 2246 } 2247 2248 err = create_hyp_mappings(kvm_ksym_ref(__start_rodata), 2249 kvm_ksym_ref(__end_rodata), PAGE_HYP_RO); 2250 if (err) { 2251 kvm_err("Cannot map rodata section\n"); 2252 goto out_err; 2253 } 2254 2255 /* 2256 * .hyp.bss is guaranteed to be placed at the beginning of the .bss 2257 * section thanks to an assertion in the linker script. Map it RW and 2258 * the rest of .bss RO. 2259 */ 2260 err = create_hyp_mappings(kvm_ksym_ref(__hyp_bss_start), 2261 kvm_ksym_ref(__hyp_bss_end), PAGE_HYP); 2262 if (err) { 2263 kvm_err("Cannot map hyp bss section: %d\n", err); 2264 goto out_err; 2265 } 2266 2267 err = create_hyp_mappings(kvm_ksym_ref(__hyp_bss_end), 2268 kvm_ksym_ref(__bss_stop), PAGE_HYP_RO); 2269 if (err) { 2270 kvm_err("Cannot map bss section\n"); 2271 goto out_err; 2272 } 2273 2274 /* 2275 * Map the Hyp stack pages 2276 */ 2277 for_each_possible_cpu(cpu) { 2278 struct kvm_nvhe_init_params *params = per_cpu_ptr_nvhe_sym(kvm_init_params, cpu); 2279 char *stack_page = (char *)per_cpu(kvm_arm_hyp_stack_page, cpu); 2280 unsigned long hyp_addr; 2281 2282 /* 2283 * Allocate a contiguous HYP private VA range for the stack 2284 * and guard page. The allocation is also aligned based on 2285 * the order of its size. 2286 */ 2287 err = hyp_alloc_private_va_range(PAGE_SIZE * 2, &hyp_addr); 2288 if (err) { 2289 kvm_err("Cannot allocate hyp stack guard page\n"); 2290 goto out_err; 2291 } 2292 2293 /* 2294 * Since the stack grows downwards, map the stack to the page 2295 * at the higher address and leave the lower guard page 2296 * unbacked. 2297 * 2298 * Any valid stack address now has the PAGE_SHIFT bit as 1 2299 * and addresses corresponding to the guard page have the 2300 * PAGE_SHIFT bit as 0 - this is used for overflow detection. 2301 */ 2302 err = __create_hyp_mappings(hyp_addr + PAGE_SIZE, PAGE_SIZE, 2303 __pa(stack_page), PAGE_HYP); 2304 if (err) { 2305 kvm_err("Cannot map hyp stack\n"); 2306 goto out_err; 2307 } 2308 2309 /* 2310 * Save the stack PA in nvhe_init_params. This will be needed 2311 * to recreate the stack mapping in protected nVHE mode. 2312 * __hyp_pa() won't do the right thing there, since the stack 2313 * has been mapped in the flexible private VA space. 2314 */ 2315 params->stack_pa = __pa(stack_page); 2316 2317 params->stack_hyp_va = hyp_addr + (2 * PAGE_SIZE); 2318 } 2319 2320 for_each_possible_cpu(cpu) { 2321 char *percpu_begin = (char *)kvm_nvhe_sym(kvm_arm_hyp_percpu_base)[cpu]; 2322 char *percpu_end = percpu_begin + nvhe_percpu_size(); 2323 2324 /* Map Hyp percpu pages */ 2325 err = create_hyp_mappings(percpu_begin, percpu_end, PAGE_HYP); 2326 if (err) { 2327 kvm_err("Cannot map hyp percpu region\n"); 2328 goto out_err; 2329 } 2330 2331 /* Prepare the CPU initialization parameters */ 2332 cpu_prepare_hyp_mode(cpu, hyp_va_bits); 2333 } 2334 2335 kvm_hyp_init_symbols(); 2336 2337 if (is_protected_kvm_enabled()) { 2338 if (IS_ENABLED(CONFIG_ARM64_PTR_AUTH_KERNEL) && 2339 cpus_have_const_cap(ARM64_HAS_ADDRESS_AUTH)) 2340 pkvm_hyp_init_ptrauth(); 2341 2342 init_cpu_logical_map(); 2343 2344 if (!init_psci_relay()) { 2345 err = -ENODEV; 2346 goto out_err; 2347 } 2348 2349 err = kvm_hyp_init_protection(hyp_va_bits); 2350 if (err) { 2351 kvm_err("Failed to init hyp memory protection\n"); 2352 goto out_err; 2353 } 2354 } 2355 2356 return 0; 2357 2358 out_err: 2359 teardown_hyp_mode(); 2360 kvm_err("error initializing Hyp mode: %d\n", err); 2361 return err; 2362 } 2363 2364 struct kvm_vcpu *kvm_mpidr_to_vcpu(struct kvm *kvm, unsigned long mpidr) 2365 { 2366 struct kvm_vcpu *vcpu; 2367 unsigned long i; 2368 2369 mpidr &= MPIDR_HWID_BITMASK; 2370 kvm_for_each_vcpu(i, vcpu, kvm) { 2371 if (mpidr == kvm_vcpu_get_mpidr_aff(vcpu)) 2372 return vcpu; 2373 } 2374 return NULL; 2375 } 2376 2377 bool kvm_arch_irqchip_in_kernel(struct kvm *kvm) 2378 { 2379 return irqchip_in_kernel(kvm); 2380 } 2381 2382 bool kvm_arch_has_irq_bypass(void) 2383 { 2384 return true; 2385 } 2386 2387 int kvm_arch_irq_bypass_add_producer(struct irq_bypass_consumer *cons, 2388 struct irq_bypass_producer *prod) 2389 { 2390 struct kvm_kernel_irqfd *irqfd = 2391 container_of(cons, struct kvm_kernel_irqfd, consumer); 2392 2393 return kvm_vgic_v4_set_forwarding(irqfd->kvm, prod->irq, 2394 &irqfd->irq_entry); 2395 } 2396 void kvm_arch_irq_bypass_del_producer(struct irq_bypass_consumer *cons, 2397 struct irq_bypass_producer *prod) 2398 { 2399 struct kvm_kernel_irqfd *irqfd = 2400 container_of(cons, struct kvm_kernel_irqfd, consumer); 2401 2402 kvm_vgic_v4_unset_forwarding(irqfd->kvm, prod->irq, 2403 &irqfd->irq_entry); 2404 } 2405 2406 void kvm_arch_irq_bypass_stop(struct irq_bypass_consumer *cons) 2407 { 2408 struct kvm_kernel_irqfd *irqfd = 2409 container_of(cons, struct kvm_kernel_irqfd, consumer); 2410 2411 kvm_arm_halt_guest(irqfd->kvm); 2412 } 2413 2414 void kvm_arch_irq_bypass_start(struct irq_bypass_consumer *cons) 2415 { 2416 struct kvm_kernel_irqfd *irqfd = 2417 container_of(cons, struct kvm_kernel_irqfd, consumer); 2418 2419 kvm_arm_resume_guest(irqfd->kvm); 2420 } 2421 2422 /* Initialize Hyp-mode and memory mappings on all CPUs */ 2423 static __init int kvm_arm_init(void) 2424 { 2425 int err; 2426 bool in_hyp_mode; 2427 2428 if (!is_hyp_mode_available()) { 2429 kvm_info("HYP mode not available\n"); 2430 return -ENODEV; 2431 } 2432 2433 if (kvm_get_mode() == KVM_MODE_NONE) { 2434 kvm_info("KVM disabled from command line\n"); 2435 return -ENODEV; 2436 } 2437 2438 err = kvm_sys_reg_table_init(); 2439 if (err) { 2440 kvm_info("Error initializing system register tables"); 2441 return err; 2442 } 2443 2444 in_hyp_mode = is_kernel_in_hyp_mode(); 2445 2446 if (cpus_have_final_cap(ARM64_WORKAROUND_DEVICE_LOAD_ACQUIRE) || 2447 cpus_have_final_cap(ARM64_WORKAROUND_1508412)) 2448 kvm_info("Guests without required CPU erratum workarounds can deadlock system!\n" \ 2449 "Only trusted guests should be used on this system.\n"); 2450 2451 err = kvm_set_ipa_limit(); 2452 if (err) 2453 return err; 2454 2455 err = kvm_arm_init_sve(); 2456 if (err) 2457 return err; 2458 2459 err = kvm_arm_vmid_alloc_init(); 2460 if (err) { 2461 kvm_err("Failed to initialize VMID allocator.\n"); 2462 return err; 2463 } 2464 2465 if (!in_hyp_mode) { 2466 err = init_hyp_mode(); 2467 if (err) 2468 goto out_err; 2469 } 2470 2471 err = kvm_init_vector_slots(); 2472 if (err) { 2473 kvm_err("Cannot initialise vector slots\n"); 2474 goto out_hyp; 2475 } 2476 2477 err = init_subsystems(); 2478 if (err) 2479 goto out_hyp; 2480 2481 if (is_protected_kvm_enabled()) { 2482 kvm_info("Protected nVHE mode initialized successfully\n"); 2483 } else if (in_hyp_mode) { 2484 kvm_info("VHE mode initialized successfully\n"); 2485 } else { 2486 kvm_info("Hyp mode initialized successfully\n"); 2487 } 2488 2489 /* 2490 * FIXME: Do something reasonable if kvm_init() fails after pKVM 2491 * hypervisor protection is finalized. 2492 */ 2493 err = kvm_init(sizeof(struct kvm_vcpu), 0, THIS_MODULE); 2494 if (err) 2495 goto out_subs; 2496 2497 kvm_arm_initialised = true; 2498 2499 return 0; 2500 2501 out_subs: 2502 teardown_subsystems(); 2503 out_hyp: 2504 if (!in_hyp_mode) 2505 teardown_hyp_mode(); 2506 out_err: 2507 kvm_arm_vmid_alloc_free(); 2508 return err; 2509 } 2510 2511 static int __init early_kvm_mode_cfg(char *arg) 2512 { 2513 if (!arg) 2514 return -EINVAL; 2515 2516 if (strcmp(arg, "none") == 0) { 2517 kvm_mode = KVM_MODE_NONE; 2518 return 0; 2519 } 2520 2521 if (!is_hyp_mode_available()) { 2522 pr_warn_once("KVM is not available. Ignoring kvm-arm.mode\n"); 2523 return 0; 2524 } 2525 2526 if (strcmp(arg, "protected") == 0) { 2527 if (!is_kernel_in_hyp_mode()) 2528 kvm_mode = KVM_MODE_PROTECTED; 2529 else 2530 pr_warn_once("Protected KVM not available with VHE\n"); 2531 2532 return 0; 2533 } 2534 2535 if (strcmp(arg, "nvhe") == 0 && !WARN_ON(is_kernel_in_hyp_mode())) { 2536 kvm_mode = KVM_MODE_DEFAULT; 2537 return 0; 2538 } 2539 2540 if (strcmp(arg, "nested") == 0 && !WARN_ON(!is_kernel_in_hyp_mode())) { 2541 kvm_mode = KVM_MODE_NV; 2542 return 0; 2543 } 2544 2545 return -EINVAL; 2546 } 2547 early_param("kvm-arm.mode", early_kvm_mode_cfg); 2548 2549 enum kvm_mode kvm_get_mode(void) 2550 { 2551 return kvm_mode; 2552 } 2553 2554 module_init(kvm_arm_init); 2555