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