arch/arm64/kvm/arm.c

   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_nested.h>
  40 #include <asm/kvm_pkvm.h>
  41 #include <asm/kvm_emulate.h>
  42 #include <asm/sections.h>
  43
  44 #include <kvm/arm_hypercalls.h>
  45 #include <kvm/arm_pmu.h>
  46 #include <kvm/arm_psci.h>
  47
  48 static enum kvm_mode kvm_mode = KVM_MODE_DEFAULT;
  49
  50 DECLARE_KVM_HYP_PER_CPU(unsigned long, kvm_hyp_vector);
  51
  52 DEFINE_PER_CPU(unsigned long, kvm_arm_hyp_stack_page);
  53 DECLARE_KVM_NVHE_PER_CPU(struct kvm_nvhe_init_params, kvm_init_params);
  54
  55 DECLARE_KVM_NVHE_PER_CPU(struct kvm_cpu_context, kvm_hyp_ctxt);
  56
  57 static bool vgic_present, kvm_arm_initialised;
  58
  59 static DEFINE_PER_CPU(unsigned char, kvm_hyp_initialized);
  60 DEFINE_STATIC_KEY_FALSE(userspace_irqchip_in_use);
  61
  62 bool is_kvm_arm_initialised(void)
  63 {
  64         return kvm_arm_initialised;
  65 }
  66
  67 int kvm_arch_vcpu_should_kick(struct kvm_vcpu *vcpu)
  68 {
  69         return kvm_vcpu_exiting_guest_mode(vcpu) == IN_GUEST_MODE;
  70 }
  71
  72 int kvm_vm_ioctl_enable_cap(struct kvm *kvm,
  73                             struct kvm_enable_cap *cap)
  74 {
  75         int r;
  76         u64 new_cap;
  77
  78         if (cap->flags)
  79                 return -EINVAL;
  80
  81         switch (cap->cap) {
  82         case KVM_CAP_ARM_NISV_TO_USER:
  83                 r = 0;
  84                 set_bit(KVM_ARCH_FLAG_RETURN_NISV_IO_ABORT_TO_USER,
  85                         &kvm->arch.flags);
  86                 break;
  87         case KVM_CAP_ARM_MTE:
  88                 mutex_lock(&kvm->lock);
  89                 if (!system_supports_mte() || kvm->created_vcpus) {
  90                         r = -EINVAL;
  91                 } else {
  92                         r = 0;
  93                         set_bit(KVM_ARCH_FLAG_MTE_ENABLED, &kvm->arch.flags);
  94                 }
  95                 mutex_unlock(&kvm->lock);
  96                 break;
  97         case KVM_CAP_ARM_SYSTEM_SUSPEND:
  98                 r = 0;
  99                 set_bit(KVM_ARCH_FLAG_SYSTEM_SUSPEND_ENABLED, &kvm->arch.flags);
 100                 break;
 101         case KVM_CAP_ARM_EAGER_SPLIT_CHUNK_SIZE:
 102                 new_cap = cap->args[0];
 103
 104                 mutex_lock(&kvm->slots_lock);
 105                 /*
 106                  * To keep things simple, allow changing the chunk
 107                  * size only when no memory slots have been created.
 108                  */
 109                 if (!kvm_are_all_memslots_empty(kvm)) {
 110                         r = -EINVAL;
 111                 } else if (new_cap && !kvm_is_block_size_supported(new_cap)) {
 112                         r = -EINVAL;
 113                 } else {
 114                         r = 0;
 115                         kvm->arch.mmu.split_page_chunk_size = new_cap;
 116                 }
 117                 mutex_unlock(&kvm->slots_lock);
 118                 break;
 119         default:
 120                 r = -EINVAL;
 121                 break;
 122         }
 123
 124         return r;
 125 }
 126
 127 static int kvm_arm_default_max_vcpus(void)
 128 {
 129         return vgic_present ? kvm_vgic_get_max_vcpus() : KVM_MAX_VCPUS;
 130 }
 131
 132 /**
 133  * kvm_arch_init_vm - initializes a VM data structure
 134  * @kvm:        pointer to the KVM struct
 135  */
 136 int kvm_arch_init_vm(struct kvm *kvm, unsigned long type)
 137 {
 138         int ret;
 139
 140         mutex_init(&kvm->arch.config_lock);
 141
 142 #ifdef CONFIG_LOCKDEP
 143         /* Clue in lockdep that the config_lock must be taken inside kvm->lock */
 144         mutex_lock(&kvm->lock);
 145         mutex_lock(&kvm->arch.config_lock);
 146         mutex_unlock(&kvm->arch.config_lock);
 147         mutex_unlock(&kvm->lock);
 148 #endif
 149
 150         ret = kvm_share_hyp(kvm, kvm + 1);
 151         if (ret)
 152                 return ret;
 153
 154         ret = pkvm_init_host_vm(kvm);
 155         if (ret)
 156                 goto err_unshare_kvm;
 157
 158         if (!zalloc_cpumask_var(&kvm->arch.supported_cpus, GFP_KERNEL_ACCOUNT)) {
 159                 ret = -ENOMEM;
 160                 goto err_unshare_kvm;
 161         }
 162         cpumask_copy(kvm->arch.supported_cpus, cpu_possible_mask);
 163
 164         ret = kvm_init_stage2_mmu(kvm, &kvm->arch.mmu, type);
 165         if (ret)
 166                 goto err_free_cpumask;
 167
 168         kvm_vgic_early_init(kvm);
 169
 170         kvm_timer_init_vm(kvm);
 171
 172         /* The maximum number of VCPUs is limited by the host's GIC model */
 173         kvm->max_vcpus = kvm_arm_default_max_vcpus();
 174
 175         kvm_arm_init_hypercalls(kvm);
 176
 177         bitmap_zero(kvm->arch.vcpu_features, KVM_VCPU_MAX_FEATURES);
 178
 179         return 0;
 180
 181 err_free_cpumask:
 182         free_cpumask_var(kvm->arch.supported_cpus);
 183 err_unshare_kvm:
 184         kvm_unshare_hyp(kvm, kvm + 1);
 185         return ret;
 186 }
 187
 188 vm_fault_t kvm_arch_vcpu_fault(struct kvm_vcpu *vcpu, struct vm_fault *vmf)
 189 {
 190         return VM_FAULT_SIGBUS;
 191 }
 192
 193
 194 /**
 195  * kvm_arch_destroy_vm - destroy the VM data structure
 196  * @kvm:        pointer to the KVM struct
 197  */
 198 void kvm_arch_destroy_vm(struct kvm *kvm)
 199 {
 200         bitmap_free(kvm->arch.pmu_filter);
 201         free_cpumask_var(kvm->arch.supported_cpus);
 202
 203         kvm_vgic_destroy(kvm);
 204
 205         if (is_protected_kvm_enabled())
 206                 pkvm_destroy_hyp_vm(kvm);
 207
 208         kvm_destroy_vcpus(kvm);
 209
 210         kvm_unshare_hyp(kvm, kvm + 1);
 211
 212         kvm_arm_teardown_hypercalls(kvm);
 213 }
 214
 215 int kvm_vm_ioctl_check_extension(struct kvm *kvm, long ext)
 216 {
 217         int r;
 218         switch (ext) {
 219         case KVM_CAP_IRQCHIP:
 220                 r = vgic_present;
 221                 break;
 222         case KVM_CAP_IOEVENTFD:
 223         case KVM_CAP_DEVICE_CTRL:
 224         case KVM_CAP_USER_MEMORY:
 225         case KVM_CAP_SYNC_MMU:
 226         case KVM_CAP_DESTROY_MEMORY_REGION_WORKS:
 227         case KVM_CAP_ONE_REG:
 228         case KVM_CAP_ARM_PSCI:
 229         case KVM_CAP_ARM_PSCI_0_2:
 230         case KVM_CAP_READONLY_MEM:
 231         case KVM_CAP_MP_STATE:
 232         case KVM_CAP_IMMEDIATE_EXIT:
 233         case KVM_CAP_VCPU_EVENTS:
 234         case KVM_CAP_ARM_IRQ_LINE_LAYOUT_2:
 235         case KVM_CAP_ARM_NISV_TO_USER:
 236         case KVM_CAP_ARM_INJECT_EXT_DABT:
 237         case KVM_CAP_SET_GUEST_DEBUG:
 238         case KVM_CAP_VCPU_ATTRIBUTES:
 239         case KVM_CAP_PTP_KVM:
 240         case KVM_CAP_ARM_SYSTEM_SUSPEND:
 241         case KVM_CAP_IRQFD_RESAMPLE:
 242         case KVM_CAP_COUNTER_OFFSET:
 243                 r = 1;
 244                 break;
 245         case KVM_CAP_SET_GUEST_DEBUG2:
 246                 return KVM_GUESTDBG_VALID_MASK;
 247         case KVM_CAP_ARM_SET_DEVICE_ADDR:
 248                 r = 1;
 249                 break;
 250         case KVM_CAP_NR_VCPUS:
 251                 /*
 252                  * ARM64 treats KVM_CAP_NR_CPUS differently from all other
 253                  * architectures, as it does not always bound it to
 254                  * KVM_CAP_MAX_VCPUS. It should not matter much because
 255                  * this is just an advisory value.
 256                  */
 257                 r = min_t(unsigned int, num_online_cpus(),
 258                           kvm_arm_default_max_vcpus());
 259                 break;
 260         case KVM_CAP_MAX_VCPUS:
 261         case KVM_CAP_MAX_VCPU_ID:
 262                 if (kvm)
 263                         r = kvm->max_vcpus;
 264                 else
 265                         r = kvm_arm_default_max_vcpus();
 266                 break;
 267         case KVM_CAP_MSI_DEVID:
 268                 if (!kvm)
 269                         r = -EINVAL;
 270                 else
 271                         r = kvm->arch.vgic.msis_require_devid;
 272                 break;
 273         case KVM_CAP_ARM_USER_IRQ:
 274                 /*
 275                  * 1: EL1_VTIMER, EL1_PTIMER, and PMU.
 276                  * (bump this number if adding more devices)
 277                  */
 278                 r = 1;
 279                 break;
 280         case KVM_CAP_ARM_MTE:
 281                 r = system_supports_mte();
 282                 break;
 283         case KVM_CAP_STEAL_TIME:
 284                 r = kvm_arm_pvtime_supported();
 285                 break;
 286         case KVM_CAP_ARM_EL1_32BIT:
 287                 r = cpus_have_const_cap(ARM64_HAS_32BIT_EL1);
 288                 break;
 289         case KVM_CAP_GUEST_DEBUG_HW_BPS:
 290                 r = get_num_brps();
 291                 break;
 292         case KVM_CAP_GUEST_DEBUG_HW_WPS:
 293                 r = get_num_wrps();
 294                 break;
 295         case KVM_CAP_ARM_PMU_V3:
 296                 r = kvm_arm_support_pmu_v3();
 297                 break;
 298         case KVM_CAP_ARM_INJECT_SERROR_ESR:
 299                 r = cpus_have_const_cap(ARM64_HAS_RAS_EXTN);
 300                 break;
 301         case KVM_CAP_ARM_VM_IPA_SIZE:
 302                 r = get_kvm_ipa_limit();
 303                 break;
 304         case KVM_CAP_ARM_SVE:
 305                 r = system_supports_sve();
 306                 break;
 307         case KVM_CAP_ARM_PTRAUTH_ADDRESS:
 308         case KVM_CAP_ARM_PTRAUTH_GENERIC:
 309                 r = system_has_full_ptr_auth();
 310                 break;
 311         case KVM_CAP_ARM_EAGER_SPLIT_CHUNK_SIZE:
 312                 if (kvm)
 313                         r = kvm->arch.mmu.split_page_chunk_size;
 314                 else
 315                         r = KVM_ARM_EAGER_SPLIT_CHUNK_SIZE_DEFAULT;
 316                 break;
 317         case KVM_CAP_ARM_SUPPORTED_BLOCK_SIZES:
 318                 r = kvm_supported_block_sizes();
 319                 break;
 320         default:
 321                 r = 0;
 322         }
 323
 324         return r;
 325 }
 326
 327 long kvm_arch_dev_ioctl(struct file *filp,
 328                         unsigned int ioctl, unsigned long arg)
 329 {
 330         return -EINVAL;
 331 }
 332
 333 struct kvm *kvm_arch_alloc_vm(void)
 334 {
 335         size_t sz = sizeof(struct kvm);
 336
 337         if (!has_vhe())
 338                 return kzalloc(sz, GFP_KERNEL_ACCOUNT);
 339
 340         return __vmalloc(sz, GFP_KERNEL_ACCOUNT | __GFP_HIGHMEM | __GFP_ZERO);
 341 }
 342
 343 int kvm_arch_vcpu_precreate(struct kvm *kvm, unsigned int id)
 344 {
 345         if (irqchip_in_kernel(kvm) && vgic_initialized(kvm))
 346                 return -EBUSY;
 347
 348         if (id >= kvm->max_vcpus)
 349                 return -EINVAL;
 350
 351         return 0;
 352 }
 353
 354 int kvm_arch_vcpu_create(struct kvm_vcpu *vcpu)
 355 {
 356         int err;
 357
 358         spin_lock_init(&vcpu->arch.mp_state_lock);
 359
 360 #ifdef CONFIG_LOCKDEP
 361         /* Inform lockdep that the config_lock is acquired after vcpu->mutex */
 362         mutex_lock(&vcpu->mutex);
 363         mutex_lock(&vcpu->kvm->arch.config_lock);
 364         mutex_unlock(&vcpu->kvm->arch.config_lock);
 365         mutex_unlock(&vcpu->mutex);
 366 #endif
 367
 368         /* Force users to call KVM_ARM_VCPU_INIT */
 369         vcpu_clear_flag(vcpu, VCPU_INITIALIZED);
 370         bitmap_zero(vcpu->arch.features, KVM_VCPU_MAX_FEATURES);
 371
 372         vcpu->arch.mmu_page_cache.gfp_zero = __GFP_ZERO;
 373
 374         /*
 375          * Default value for the FP state, will be overloaded at load
 376          * time if we support FP (pretty likely)
 377          */
 378         vcpu->arch.fp_state = FP_STATE_FREE;
 379
 380         /* Set up the timer */
 381         kvm_timer_vcpu_init(vcpu);
 382
 383         kvm_pmu_vcpu_init(vcpu);
 384
 385         kvm_arm_reset_debug_ptr(vcpu);
 386
 387         kvm_arm_pvtime_vcpu_init(&vcpu->arch);
 388
 389         vcpu->arch.hw_mmu = &vcpu->kvm->arch.mmu;
 390
 391         err = kvm_vgic_vcpu_init(vcpu);
 392         if (err)
 393                 return err;
 394
 395         return kvm_share_hyp(vcpu, vcpu + 1);
 396 }
 397
 398 void kvm_arch_vcpu_postcreate(struct kvm_vcpu *vcpu)
 399 {
 400 }
 401
 402 void kvm_arch_vcpu_destroy(struct kvm_vcpu *vcpu)
 403 {
 404         if (vcpu_has_run_once(vcpu) && unlikely(!irqchip_in_kernel(vcpu->kvm)))
 405                 static_branch_dec(&userspace_irqchip_in_use);
 406
 407         kvm_mmu_free_memory_cache(&vcpu->arch.mmu_page_cache);
 408         kvm_timer_vcpu_terminate(vcpu);
 409         kvm_pmu_vcpu_destroy(vcpu);
 410
 411         kvm_arm_vcpu_destroy(vcpu);
 412 }
 413
 414 void kvm_arch_vcpu_blocking(struct kvm_vcpu *vcpu)
 415 {
 416
 417 }
 418
 419 void kvm_arch_vcpu_unblocking(struct kvm_vcpu *vcpu)
 420 {
 421
 422 }
 423
 424 void kvm_arch_vcpu_load(struct kvm_vcpu *vcpu, int cpu)
 425 {
 426         struct kvm_s2_mmu *mmu;
 427         int *last_ran;
 428
 429         mmu = vcpu->arch.hw_mmu;
 430         last_ran = this_cpu_ptr(mmu->last_vcpu_ran);
 431
 432         /*
 433          * We guarantee that both TLBs and I-cache are private to each
 434          * vcpu. If detecting that a vcpu from the same VM has
 435          * previously run on the same physical CPU, call into the
 436          * hypervisor code to nuke the relevant contexts.
 437          *
 438          * We might get preempted before the vCPU actually runs, but
 439          * over-invalidation doesn't affect correctness.
 440          */
 441         if (*last_ran != vcpu->vcpu_id) {
 442                 kvm_call_hyp(__kvm_flush_cpu_context, mmu);
 443                 *last_ran = vcpu->vcpu_id;
 444         }
 445
 446         vcpu->cpu = cpu;
 447
 448         kvm_vgic_load(vcpu);
 449         kvm_timer_vcpu_load(vcpu);
 450         if (has_vhe())
 451                 kvm_vcpu_load_sysregs_vhe(vcpu);
 452         kvm_arch_vcpu_load_fp(vcpu);
 453         kvm_vcpu_pmu_restore_guest(vcpu);
 454         if (kvm_arm_is_pvtime_enabled(&vcpu->arch))
 455                 kvm_make_request(KVM_REQ_RECORD_STEAL, vcpu);
 456
 457         if (single_task_running())
 458                 vcpu_clear_wfx_traps(vcpu);
 459         else
 460                 vcpu_set_wfx_traps(vcpu);
 461
 462         if (vcpu_has_ptrauth(vcpu))
 463                 vcpu_ptrauth_disable(vcpu);
 464         kvm_arch_vcpu_load_debug_state_flags(vcpu);
 465
 466         if (!cpumask_test_cpu(cpu, vcpu->kvm->arch.supported_cpus))
 467                 vcpu_set_on_unsupported_cpu(vcpu);
 468 }
 469
 470 void kvm_arch_vcpu_put(struct kvm_vcpu *vcpu)
 471 {
 472         kvm_arch_vcpu_put_debug_state_flags(vcpu);
 473         kvm_arch_vcpu_put_fp(vcpu);
 474         if (has_vhe())
 475                 kvm_vcpu_put_sysregs_vhe(vcpu);
 476         kvm_timer_vcpu_put(vcpu);
 477         kvm_vgic_put(vcpu);
 478         kvm_vcpu_pmu_restore_host(vcpu);
 479         kvm_arm_vmid_clear_active();
 480
 481         vcpu_clear_on_unsupported_cpu(vcpu);
 482         vcpu->cpu = -1;
 483 }
 484
 485 static void __kvm_arm_vcpu_power_off(struct kvm_vcpu *vcpu)
 486 {
 487         WRITE_ONCE(vcpu->arch.mp_state.mp_state, KVM_MP_STATE_STOPPED);
 488         kvm_make_request(KVM_REQ_SLEEP, vcpu);
 489         kvm_vcpu_kick(vcpu);
 490 }
 491
 492 void kvm_arm_vcpu_power_off(struct kvm_vcpu *vcpu)
 493 {
 494         spin_lock(&vcpu->arch.mp_state_lock);
 495         __kvm_arm_vcpu_power_off(vcpu);
 496         spin_unlock(&vcpu->arch.mp_state_lock);
 497 }
 498
 499 bool kvm_arm_vcpu_stopped(struct kvm_vcpu *vcpu)
 500 {
 501         return READ_ONCE(vcpu->arch.mp_state.mp_state) == KVM_MP_STATE_STOPPED;
 502 }
 503
 504 static void kvm_arm_vcpu_suspend(struct kvm_vcpu *vcpu)
 505 {
 506         WRITE_ONCE(vcpu->arch.mp_state.mp_state, KVM_MP_STATE_SUSPENDED);
 507         kvm_make_request(KVM_REQ_SUSPEND, vcpu);
 508         kvm_vcpu_kick(vcpu);
 509 }
 510
 511 static bool kvm_arm_vcpu_suspended(struct kvm_vcpu *vcpu)
 512 {
 513         return READ_ONCE(vcpu->arch.mp_state.mp_state) == KVM_MP_STATE_SUSPENDED;
 514 }
 515
 516 int kvm_arch_vcpu_ioctl_get_mpstate(struct kvm_vcpu *vcpu,
 517                                     struct kvm_mp_state *mp_state)
 518 {
 519         *mp_state = READ_ONCE(vcpu->arch.mp_state);
 520
 521         return 0;
 522 }
 523
 524 int kvm_arch_vcpu_ioctl_set_mpstate(struct kvm_vcpu *vcpu,
 525                                     struct kvm_mp_state *mp_state)
 526 {
 527         int ret = 0;
 528
 529         spin_lock(&vcpu->arch.mp_state_lock);
 530
 531         switch (mp_state->mp_state) {
 532         case KVM_MP_STATE_RUNNABLE:
 533                 WRITE_ONCE(vcpu->arch.mp_state, *mp_state);
 534                 break;
 535         case KVM_MP_STATE_STOPPED:
 536                 __kvm_arm_vcpu_power_off(vcpu);
 537                 break;
 538         case KVM_MP_STATE_SUSPENDED:
 539                 kvm_arm_vcpu_suspend(vcpu);
 540                 break;
 541         default:
 542                 ret = -EINVAL;
 543         }
 544
 545         spin_unlock(&vcpu->arch.mp_state_lock);
 546
 547         return ret;
 548 }
 549
 550 /**
 551  * kvm_arch_vcpu_runnable - determine if the vcpu can be scheduled
 552  * @v:          The VCPU pointer
 553  *
 554  * If the guest CPU is not waiting for interrupts or an interrupt line is
 555  * asserted, the CPU is by definition runnable.
 556  */
 557 int kvm_arch_vcpu_runnable(struct kvm_vcpu *v)
 558 {
 559         bool irq_lines = *vcpu_hcr(v) & (HCR_VI | HCR_VF);
 560         return ((irq_lines || kvm_vgic_vcpu_pending_irq(v))
 561                 && !kvm_arm_vcpu_stopped(v) && !v->arch.pause);
 562 }
 563
 564 bool kvm_arch_vcpu_in_kernel(struct kvm_vcpu *vcpu)
 565 {
 566         return vcpu_mode_priv(vcpu);
 567 }
 568
 569 #ifdef CONFIG_GUEST_PERF_EVENTS
 570 unsigned long kvm_arch_vcpu_get_ip(struct kvm_vcpu *vcpu)
 571 {
 572         return *vcpu_pc(vcpu);
 573 }
 574 #endif
 575
 576 static int kvm_vcpu_initialized(struct kvm_vcpu *vcpu)
 577 {
 578         return vcpu_get_flag(vcpu, VCPU_INITIALIZED);
 579 }
 580
 581 /*
 582  * Handle both the initialisation that is being done when the vcpu is
 583  * run for the first time, as well as the updates that must be
 584  * performed each time we get a new thread dealing with this vcpu.
 585  */
 586 int kvm_arch_vcpu_run_pid_change(struct kvm_vcpu *vcpu)
 587 {
 588         struct kvm *kvm = vcpu->kvm;
 589         int ret;
 590
 591         if (!kvm_vcpu_initialized(vcpu))
 592                 return -ENOEXEC;
 593
 594         if (!kvm_arm_vcpu_is_finalized(vcpu))
 595                 return -EPERM;
 596
 597         ret = kvm_arch_vcpu_run_map_fp(vcpu);
 598         if (ret)
 599                 return ret;
 600
 601         if (likely(vcpu_has_run_once(vcpu)))
 602                 return 0;
 603
 604         kvm_arm_vcpu_init_debug(vcpu);
 605
 606         if (likely(irqchip_in_kernel(kvm))) {
 607                 /*
 608                  * Map the VGIC hardware resources before running a vcpu the
 609                  * first time on this VM.
 610                  */
 611                 ret = kvm_vgic_map_resources(kvm);
 612                 if (ret)
 613                         return ret;
 614         }
 615
 616         ret = kvm_timer_enable(vcpu);
 617         if (ret)
 618                 return ret;
 619
 620         ret = kvm_arm_pmu_v3_enable(vcpu);
 621         if (ret)
 622                 return ret;
 623
 624         if (is_protected_kvm_enabled()) {
 625                 ret = pkvm_create_hyp_vm(kvm);
 626                 if (ret)
 627                         return ret;
 628         }
 629
 630         if (!irqchip_in_kernel(kvm)) {
 631                 /*
 632                  * Tell the rest of the code that there are userspace irqchip
 633                  * VMs in the wild.
 634                  */
 635                 static_branch_inc(&userspace_irqchip_in_use);
 636         }
 637
 638         /*
 639          * Initialize traps for protected VMs.
 640          * NOTE: Move to run in EL2 directly, rather than via a hypercall, once
 641          * the code is in place for first run initialization at EL2.
 642          */
 643         if (kvm_vm_is_protected(kvm))
 644                 kvm_call_hyp_nvhe(__pkvm_vcpu_init_traps, vcpu);
 645
 646         mutex_lock(&kvm->arch.config_lock);
 647         set_bit(KVM_ARCH_FLAG_HAS_RAN_ONCE, &kvm->arch.flags);
 648         mutex_unlock(&kvm->arch.config_lock);
 649
 650         return ret;
 651 }
 652
 653 bool kvm_arch_intc_initialized(struct kvm *kvm)
 654 {
 655         return vgic_initialized(kvm);
 656 }
 657
 658 void kvm_arm_halt_guest(struct kvm *kvm)
 659 {
 660         unsigned long i;
 661         struct kvm_vcpu *vcpu;
 662
 663         kvm_for_each_vcpu(i, vcpu, kvm)
 664                 vcpu->arch.pause = true;
 665         kvm_make_all_cpus_request(kvm, KVM_REQ_SLEEP);
 666 }
 667
 668 void kvm_arm_resume_guest(struct kvm *kvm)
 669 {
 670         unsigned long i;
 671         struct kvm_vcpu *vcpu;
 672
 673         kvm_for_each_vcpu(i, vcpu, kvm) {
 674                 vcpu->arch.pause = false;
 675                 __kvm_vcpu_wake_up(vcpu);
 676         }
 677 }
 678
 679 static void kvm_vcpu_sleep(struct kvm_vcpu *vcpu)
 680 {
 681         struct rcuwait *wait = kvm_arch_vcpu_get_wait(vcpu);
 682
 683         rcuwait_wait_event(wait,
 684                            (!kvm_arm_vcpu_stopped(vcpu)) && (!vcpu->arch.pause),
 685                            TASK_INTERRUPTIBLE);
 686
 687         if (kvm_arm_vcpu_stopped(vcpu) || vcpu->arch.pause) {
 688                 /* Awaken to handle a signal, request we sleep again later. */
 689                 kvm_make_request(KVM_REQ_SLEEP, vcpu);
 690         }
 691
 692         /*
 693          * Make sure we will observe a potential reset request if we've
 694          * observed a change to the power state. Pairs with the smp_wmb() in
 695          * kvm_psci_vcpu_on().
 696          */
 697         smp_rmb();
 698 }
 699
 700 /**
 701  * kvm_vcpu_wfi - emulate Wait-For-Interrupt behavior
 702  * @vcpu:       The VCPU pointer
 703  *
 704  * Suspend execution of a vCPU until a valid wake event is detected, i.e. until
 705  * the vCPU is runnable.  The vCPU may or may not be scheduled out, depending
 706  * on when a wake event arrives, e.g. there may already be a pending wake event.
 707  */
 708 void kvm_vcpu_wfi(struct kvm_vcpu *vcpu)
 709 {
 710         /*
 711          * Sync back the state of the GIC CPU interface so that we have
 712          * the latest PMR and group enables. This ensures that
 713          * kvm_arch_vcpu_runnable has up-to-date data to decide whether
 714          * we have pending interrupts, e.g. when determining if the
 715          * vCPU should block.
 716          *
 717          * For the same reason, we want to tell GICv4 that we need
 718          * doorbells to be signalled, should an interrupt become pending.
 719          */
 720         preempt_disable();
 721         kvm_vgic_vmcr_sync(vcpu);
 722         vcpu_set_flag(vcpu, IN_WFI);
 723         vgic_v4_put(vcpu);
 724         preempt_enable();
 725
 726         kvm_vcpu_halt(vcpu);
 727         vcpu_clear_flag(vcpu, IN_WFIT);
 728
 729         preempt_disable();
 730         vcpu_clear_flag(vcpu, IN_WFI);
 731         vgic_v4_load(vcpu);
 732         preempt_enable();
 733 }
 734
 735 static int kvm_vcpu_suspend(struct kvm_vcpu *vcpu)
 736 {
 737         if (!kvm_arm_vcpu_suspended(vcpu))
 738                 return 1;
 739
 740         kvm_vcpu_wfi(vcpu);
 741
 742         /*
 743          * The suspend state is sticky; we do not leave it until userspace
 744          * explicitly marks the vCPU as runnable. Request that we suspend again
 745          * later.
 746          */
 747         kvm_make_request(KVM_REQ_SUSPEND, vcpu);
 748
 749         /*
 750          * Check to make sure the vCPU is actually runnable. If so, exit to
 751          * userspace informing it of the wakeup condition.
 752          */
 753         if (kvm_arch_vcpu_runnable(vcpu)) {
 754                 memset(&vcpu->run->system_event, 0, sizeof(vcpu->run->system_event));
 755                 vcpu->run->system_event.type = KVM_SYSTEM_EVENT_WAKEUP;
 756                 vcpu->run->exit_reason = KVM_EXIT_SYSTEM_EVENT;
 757                 return 0;
 758         }
 759
 760         /*
 761          * Otherwise, we were unblocked to process a different event, such as a
 762          * pending signal. Return 1 and allow kvm_arch_vcpu_ioctl_run() to
 763          * process the event.
 764          */
 765         return 1;
 766 }
 767
 768 /**
 769  * check_vcpu_requests - check and handle pending vCPU requests
 770  * @vcpu:       the VCPU pointer
 771  *
 772  * Return: 1 if we should enter the guest
 773  *         0 if we should exit to userspace
 774  *         < 0 if we should exit to userspace, where the return value indicates
 775  *         an error
 776  */
 777 static int check_vcpu_requests(struct kvm_vcpu *vcpu)
 778 {
 779         if (kvm_request_pending(vcpu)) {
 780                 if (kvm_check_request(KVM_REQ_SLEEP, vcpu))
 781                         kvm_vcpu_sleep(vcpu);
 782
 783                 if (kvm_check_request(KVM_REQ_VCPU_RESET, vcpu))
 784                         kvm_reset_vcpu(vcpu);
 785
 786                 /*
 787                  * Clear IRQ_PENDING requests that were made to guarantee
 788                  * that a VCPU sees new virtual interrupts.
 789                  */
 790                 kvm_check_request(KVM_REQ_IRQ_PENDING, vcpu);
 791
 792                 if (kvm_check_request(KVM_REQ_RECORD_STEAL, vcpu))
 793                         kvm_update_stolen_time(vcpu);
 794
 795                 if (kvm_check_request(KVM_REQ_RELOAD_GICv4, vcpu)) {
 796                         /* The distributor enable bits were changed */
 797                         preempt_disable();
 798                         vgic_v4_put(vcpu);
 799                         vgic_v4_load(vcpu);
 800                         preempt_enable();
 801                 }
 802
 803                 if (kvm_check_request(KVM_REQ_RELOAD_PMU, vcpu))
 804                         kvm_pmu_handle_pmcr(vcpu,
 805                                             __vcpu_sys_reg(vcpu, PMCR_EL0));
 806
 807                 if (kvm_check_request(KVM_REQ_RESYNC_PMU_EL0, vcpu))
 808                         kvm_vcpu_pmu_restore_guest(vcpu);
 809
 810                 if (kvm_check_request(KVM_REQ_SUSPEND, vcpu))
 811                         return kvm_vcpu_suspend(vcpu);
 812
 813                 if (kvm_dirty_ring_check_request(vcpu))
 814                         return 0;
 815         }
 816
 817         return 1;
 818 }
 819
 820 static bool vcpu_mode_is_bad_32bit(struct kvm_vcpu *vcpu)
 821 {
 822         if (likely(!vcpu_mode_is_32bit(vcpu)))
 823                 return false;
 824
 825         if (vcpu_has_nv(vcpu))
 826                 return true;
 827
 828         return !kvm_supports_32bit_el0();
 829 }
 830
 831 /**
 832  * kvm_vcpu_exit_request - returns true if the VCPU should *not* enter the guest
 833  * @vcpu:       The VCPU pointer
 834  * @ret:        Pointer to write optional return code
 835  *
 836  * Returns: true if the VCPU needs to return to a preemptible + interruptible
 837  *          and skip guest entry.
 838  *
 839  * This function disambiguates between two different types of exits: exits to a
 840  * preemptible + interruptible kernel context and exits to userspace. For an
 841  * exit to userspace, this function will write the return code to ret and return
 842  * true. For an exit to preemptible + interruptible kernel context (i.e. check
 843  * for pending work and re-enter), return true without writing to ret.
 844  */
 845 static bool kvm_vcpu_exit_request(struct kvm_vcpu *vcpu, int *ret)
 846 {
 847         struct kvm_run *run = vcpu->run;
 848
 849         /*
 850          * If we're using a userspace irqchip, then check if we need
 851          * to tell a userspace irqchip about timer or PMU level
 852          * changes and if so, exit to userspace (the actual level
 853          * state gets updated in kvm_timer_update_run and
 854          * kvm_pmu_update_run below).
 855          */
 856         if (static_branch_unlikely(&userspace_irqchip_in_use)) {
 857                 if (kvm_timer_should_notify_user(vcpu) ||
 858                     kvm_pmu_should_notify_user(vcpu)) {
 859                         *ret = -EINTR;
 860                         run->exit_reason = KVM_EXIT_INTR;
 861                         return true;
 862                 }
 863         }
 864
 865         if (unlikely(vcpu_on_unsupported_cpu(vcpu))) {
 866                 run->exit_reason = KVM_EXIT_FAIL_ENTRY;
 867                 run->fail_entry.hardware_entry_failure_reason = KVM_EXIT_FAIL_ENTRY_CPU_UNSUPPORTED;
 868                 run->fail_entry.cpu = smp_processor_id();
 869                 *ret = 0;
 870                 return true;
 871         }
 872
 873         return kvm_request_pending(vcpu) ||
 874                         xfer_to_guest_mode_work_pending();
 875 }
 876
 877 /*
 878  * Actually run the vCPU, entering an RCU extended quiescent state (EQS) while
 879  * the vCPU is running.
 880  *
 881  * This must be noinstr as instrumentation may make use of RCU, and this is not
 882  * safe during the EQS.
 883  */
 884 static int noinstr kvm_arm_vcpu_enter_exit(struct kvm_vcpu *vcpu)
 885 {
 886         int ret;
 887
 888         guest_state_enter_irqoff();
 889         ret = kvm_call_hyp_ret(__kvm_vcpu_run, vcpu);
 890         guest_state_exit_irqoff();
 891
 892         return ret;
 893 }
 894
 895 /**
 896  * kvm_arch_vcpu_ioctl_run - the main VCPU run function to execute guest code
 897  * @vcpu:       The VCPU pointer
 898  *
 899  * This function is called through the VCPU_RUN ioctl called from user space. It
 900  * will execute VM code in a loop until the time slice for the process is used
 901  * or some emulation is needed from user space in which case the function will
 902  * return with return value 0 and with the kvm_run structure filled in with the
 903  * required data for the requested emulation.
 904  */
 905 int kvm_arch_vcpu_ioctl_run(struct kvm_vcpu *vcpu)
 906 {
 907         struct kvm_run *run = vcpu->run;
 908         int ret;
 909
 910         if (run->exit_reason == KVM_EXIT_MMIO) {
 911                 ret = kvm_handle_mmio_return(vcpu);
 912                 if (ret)
 913                         return ret;
 914         }
 915
 916         vcpu_load(vcpu);
 917
 918         if (run->immediate_exit) {
 919                 ret = -EINTR;
 920                 goto out;
 921         }
 922
 923         kvm_sigset_activate(vcpu);
 924
 925         ret = 1;
 926         run->exit_reason = KVM_EXIT_UNKNOWN;
 927         run->flags = 0;
 928         while (ret > 0) {
 929                 /*
 930                  * Check conditions before entering the guest
 931                  */
 932                 ret = xfer_to_guest_mode_handle_work(vcpu);
 933                 if (!ret)
 934                         ret = 1;
 935
 936                 if (ret > 0)
 937                         ret = check_vcpu_requests(vcpu);
 938
 939                 /*
 940                  * Preparing the interrupts to be injected also
 941                  * involves poking the GIC, which must be done in a
 942                  * non-preemptible context.
 943                  */
 944                 preempt_disable();
 945
 946                 /*
 947                  * The VMID allocator only tracks active VMIDs per
 948                  * physical CPU, and therefore the VMID allocated may not be
 949                  * preserved on VMID roll-over if the task was preempted,
 950                  * making a thread's VMID inactive. So we need to call
 951                  * kvm_arm_vmid_update() in non-premptible context.
 952                  */
 953                 kvm_arm_vmid_update(&vcpu->arch.hw_mmu->vmid);
 954
 955                 kvm_pmu_flush_hwstate(vcpu);
 956
 957                 local_irq_disable();
 958
 959                 kvm_vgic_flush_hwstate(vcpu);
 960
 961                 kvm_pmu_update_vcpu_events(vcpu);
 962
 963                 /*
 964                  * Ensure we set mode to IN_GUEST_MODE after we disable
 965                  * interrupts and before the final VCPU requests check.
 966                  * See the comment in kvm_vcpu_exiting_guest_mode() and
 967                  * Documentation/virt/kvm/vcpu-requests.rst
 968                  */
 969                 smp_store_mb(vcpu->mode, IN_GUEST_MODE);
 970
 971                 if (ret <= 0 || kvm_vcpu_exit_request(vcpu, &ret)) {
 972                         vcpu->mode = OUTSIDE_GUEST_MODE;
 973                         isb(); /* Ensure work in x_flush_hwstate is committed */
 974                         kvm_pmu_sync_hwstate(vcpu);
 975                         if (static_branch_unlikely(&userspace_irqchip_in_use))
 976                                 kvm_timer_sync_user(vcpu);
 977                         kvm_vgic_sync_hwstate(vcpu);
 978                         local_irq_enable();
 979                         preempt_enable();
 980                         continue;
 981                 }
 982
 983                 kvm_arm_setup_debug(vcpu);
 984                 kvm_arch_vcpu_ctxflush_fp(vcpu);
 985
 986                 /**************************************************************
 987                  * Enter the guest
 988                  */
 989                 trace_kvm_entry(*vcpu_pc(vcpu));
 990                 guest_timing_enter_irqoff();
 991
 992                 ret = kvm_arm_vcpu_enter_exit(vcpu);
 993
 994                 vcpu->mode = OUTSIDE_GUEST_MODE;
 995                 vcpu->stat.exits++;
 996                 /*
 997                  * Back from guest
 998                  *************************************************************/
 999
1000                 kvm_arm_clear_debug(vcpu);
1001
1002                 /*
1003                  * We must sync the PMU state before the vgic state so
1004                  * that the vgic can properly sample the updated state of the
1005                  * interrupt line.
1006                  */
1007                 kvm_pmu_sync_hwstate(vcpu);
1008
1009                 /*
1010                  * Sync the vgic state before syncing the timer state because
1011                  * the timer code needs to know if the virtual timer
1012                  * interrupts are active.
1013                  */
1014                 kvm_vgic_sync_hwstate(vcpu);
1015
1016                 /*
1017                  * Sync the timer hardware state before enabling interrupts as
1018                  * we don't want vtimer interrupts to race with syncing the
1019                  * timer virtual interrupt state.
1020                  */
1021                 if (static_branch_unlikely(&userspace_irqchip_in_use))
1022                         kvm_timer_sync_user(vcpu);
1023
1024                 kvm_arch_vcpu_ctxsync_fp(vcpu);
1025
1026                 /*
1027                  * We must ensure that any pending interrupts are taken before
1028                  * we exit guest timing so that timer ticks are accounted as
1029                  * guest time. Transiently unmask interrupts so that any
1030                  * pending interrupts are taken.
1031                  *
1032                  * Per ARM DDI 0487G.b section D1.13.4, an ISB (or other
1033                  * context synchronization event) is necessary to ensure that
1034                  * pending interrupts are taken.
1035                  */
1036                 if (ARM_EXCEPTION_CODE(ret) == ARM_EXCEPTION_IRQ) {
1037                         local_irq_enable();
1038                         isb();
1039                         local_irq_disable();
1040                 }
1041
1042                 guest_timing_exit_irqoff();
1043
1044                 local_irq_enable();
1045
1046                 trace_kvm_exit(ret, kvm_vcpu_trap_get_class(vcpu), *vcpu_pc(vcpu));
1047
1048                 /* Exit types that need handling before we can be preempted */
1049                 handle_exit_early(vcpu, ret);
1050
1051                 preempt_enable();
1052
1053                 /*
1054                  * The ARMv8 architecture doesn't give the hypervisor
1055                  * a mechanism to prevent a guest from dropping to AArch32 EL0
1056                  * if implemented by the CPU. If we spot the guest in such
1057                  * state and that we decided it wasn't supposed to do so (like
1058                  * with the asymmetric AArch32 case), return to userspace with
1059                  * a fatal error.
1060                  */
1061                 if (vcpu_mode_is_bad_32bit(vcpu)) {
1062                         /*
1063                          * As we have caught the guest red-handed, decide that
1064                          * it isn't fit for purpose anymore by making the vcpu
1065                          * invalid. The VMM can try and fix it by issuing  a
1066                          * KVM_ARM_VCPU_INIT if it really wants to.
1067                          */
1068                         vcpu_clear_flag(vcpu, VCPU_INITIALIZED);
1069                         ret = ARM_EXCEPTION_IL;
1070                 }
1071
1072                 ret = handle_exit(vcpu, ret);
1073         }
1074
1075         /* Tell userspace about in-kernel device output levels */
1076         if (unlikely(!irqchip_in_kernel(vcpu->kvm))) {
1077                 kvm_timer_update_run(vcpu);
1078                 kvm_pmu_update_run(vcpu);
1079         }
1080
1081         kvm_sigset_deactivate(vcpu);
1082
1083 out:
1084         /*
1085          * In the unlikely event that we are returning to userspace
1086          * with pending exceptions or PC adjustment, commit these
1087          * adjustments in order to give userspace a consistent view of
1088          * the vcpu state. Note that this relies on __kvm_adjust_pc()
1089          * being preempt-safe on VHE.
1090          */
1091         if (unlikely(vcpu_get_flag(vcpu, PENDING_EXCEPTION) ||
1092                      vcpu_get_flag(vcpu, INCREMENT_PC)))
1093                 kvm_call_hyp(__kvm_adjust_pc, vcpu);
1094
1095         vcpu_put(vcpu);
1096         return ret;
1097 }
1098
1099 static int vcpu_interrupt_line(struct kvm_vcpu *vcpu, int number, bool level)
1100 {
1101         int bit_index;
1102         bool set;
1103         unsigned long *hcr;
1104
1105         if (number == KVM_ARM_IRQ_CPU_IRQ)
1106                 bit_index = __ffs(HCR_VI);
1107         else /* KVM_ARM_IRQ_CPU_FIQ */
1108                 bit_index = __ffs(HCR_VF);
1109
1110         hcr = vcpu_hcr(vcpu);
1111         if (level)
1112                 set = test_and_set_bit(bit_index, hcr);
1113         else
1114                 set = test_and_clear_bit(bit_index, hcr);
1115
1116         /*
1117          * If we didn't change anything, no need to wake up or kick other CPUs
1118          */
1119         if (set == level)
1120                 return 0;
1121
1122         /*
1123          * The vcpu irq_lines field was updated, wake up sleeping VCPUs and
1124          * trigger a world-switch round on the running physical CPU to set the
1125          * virtual IRQ/FIQ fields in the HCR appropriately.
1126          */
1127         kvm_make_request(KVM_REQ_IRQ_PENDING, vcpu);
1128         kvm_vcpu_kick(vcpu);
1129
1130         return 0;
1131 }
1132
1133 int kvm_vm_ioctl_irq_line(struct kvm *kvm, struct kvm_irq_level *irq_level,
1134                           bool line_status)
1135 {
1136         u32 irq = irq_level->irq;
1137         unsigned int irq_type, vcpu_idx, irq_num;
1138         int nrcpus = atomic_read(&kvm->online_vcpus);
1139         struct kvm_vcpu *vcpu = NULL;
1140         bool level = irq_level->level;
1141
1142         irq_type = (irq >> KVM_ARM_IRQ_TYPE_SHIFT) & KVM_ARM_IRQ_TYPE_MASK;
1143         vcpu_idx = (irq >> KVM_ARM_IRQ_VCPU_SHIFT) & KVM_ARM_IRQ_VCPU_MASK;
1144         vcpu_idx += ((irq >> KVM_ARM_IRQ_VCPU2_SHIFT) & KVM_ARM_IRQ_VCPU2_MASK) * (KVM_ARM_IRQ_VCPU_MASK + 1);
1145         irq_num = (irq >> KVM_ARM_IRQ_NUM_SHIFT) & KVM_ARM_IRQ_NUM_MASK;
1146
1147         trace_kvm_irq_line(irq_type, vcpu_idx, irq_num, irq_level->level);
1148
1149         switch (irq_type) {
1150         case KVM_ARM_IRQ_TYPE_CPU:
1151                 if (irqchip_in_kernel(kvm))
1152                         return -ENXIO;
1153
1154                 if (vcpu_idx >= nrcpus)
1155                         return -EINVAL;
1156
1157                 vcpu = kvm_get_vcpu(kvm, vcpu_idx);
1158                 if (!vcpu)
1159                         return -EINVAL;
1160
1161                 if (irq_num > KVM_ARM_IRQ_CPU_FIQ)
1162                         return -EINVAL;
1163
1164                 return vcpu_interrupt_line(vcpu, irq_num, level);
1165         case KVM_ARM_IRQ_TYPE_PPI:
1166                 if (!irqchip_in_kernel(kvm))
1167                         return -ENXIO;
1168
1169                 if (vcpu_idx >= nrcpus)
1170                         return -EINVAL;
1171
1172                 vcpu = kvm_get_vcpu(kvm, vcpu_idx);
1173                 if (!vcpu)
1174                         return -EINVAL;
1175
1176                 if (irq_num < VGIC_NR_SGIS || irq_num >= VGIC_NR_PRIVATE_IRQS)
1177                         return -EINVAL;
1178
1179                 return kvm_vgic_inject_irq(kvm, vcpu->vcpu_id, irq_num, level, NULL);
1180         case KVM_ARM_IRQ_TYPE_SPI:
1181                 if (!irqchip_in_kernel(kvm))
1182                         return -ENXIO;
1183
1184                 if (irq_num < VGIC_NR_PRIVATE_IRQS)
1185                         return -EINVAL;
1186
1187                 return kvm_vgic_inject_irq(kvm, 0, irq_num, level, NULL);
1188         }
1189
1190         return -EINVAL;
1191 }
1192
1193 static int kvm_vcpu_init_check_features(struct kvm_vcpu *vcpu,
1194                                         const struct kvm_vcpu_init *init)
1195 {
1196         unsigned long features = init->features[0];
1197         int i;
1198
1199         if (features & ~KVM_VCPU_VALID_FEATURES)
1200                 return -ENOENT;
1201
1202         for (i = 1; i < ARRAY_SIZE(init->features); i++) {
1203                 if (init->features[i])
1204                         return -ENOENT;
1205         }
1206
1207         if (!test_bit(KVM_ARM_VCPU_EL1_32BIT, &features))
1208                 return 0;
1209
1210         if (!cpus_have_const_cap(ARM64_HAS_32BIT_EL1))
1211                 return -EINVAL;
1212
1213         /* MTE is incompatible with AArch32 */
1214         if (kvm_has_mte(vcpu->kvm))
1215                 return -EINVAL;
1216
1217         /* NV is incompatible with AArch32 */
1218         if (test_bit(KVM_ARM_VCPU_HAS_EL2, &features))
1219                 return -EINVAL;
1220
1221         return 0;
1222 }
1223
1224 static bool kvm_vcpu_init_changed(struct kvm_vcpu *vcpu,
1225                                   const struct kvm_vcpu_init *init)
1226 {
1227         unsigned long features = init->features[0];
1228
1229         return !bitmap_equal(vcpu->arch.features, &features, KVM_VCPU_MAX_FEATURES);
1230 }
1231
1232 static int __kvm_vcpu_set_target(struct kvm_vcpu *vcpu,
1233                                  const struct kvm_vcpu_init *init)
1234 {
1235         unsigned long features = init->features[0];
1236         struct kvm *kvm = vcpu->kvm;
1237         int ret = -EINVAL;
1238
1239         mutex_lock(&kvm->arch.config_lock);
1240
1241         if (test_bit(KVM_ARCH_FLAG_VCPU_FEATURES_CONFIGURED, &kvm->arch.flags) &&
1242             !bitmap_equal(kvm->arch.vcpu_features, &features, KVM_VCPU_MAX_FEATURES))
1243                 goto out_unlock;
1244
1245         bitmap_copy(vcpu->arch.features, &features, KVM_VCPU_MAX_FEATURES);
1246
1247         /* Now we know what it is, we can reset it. */
1248         ret = kvm_reset_vcpu(vcpu);
1249         if (ret) {
1250                 bitmap_zero(vcpu->arch.features, KVM_VCPU_MAX_FEATURES);
1251                 goto out_unlock;
1252         }
1253
1254         bitmap_copy(kvm->arch.vcpu_features, &features, KVM_VCPU_MAX_FEATURES);
1255         set_bit(KVM_ARCH_FLAG_VCPU_FEATURES_CONFIGURED, &kvm->arch.flags);
1256         vcpu_set_flag(vcpu, VCPU_INITIALIZED);
1257 out_unlock:
1258         mutex_unlock(&kvm->arch.config_lock);
1259         return ret;
1260 }
1261
1262 static int kvm_vcpu_set_target(struct kvm_vcpu *vcpu,
1263                                const struct kvm_vcpu_init *init)
1264 {
1265         int ret;
1266
1267         if (init->target != KVM_ARM_TARGET_GENERIC_V8 &&
1268             init->target != kvm_target_cpu())
1269                 return -EINVAL;
1270
1271         ret = kvm_vcpu_init_check_features(vcpu, init);
1272         if (ret)
1273                 return ret;
1274
1275         if (!kvm_vcpu_initialized(vcpu))
1276                 return __kvm_vcpu_set_target(vcpu, init);
1277
1278         if (kvm_vcpu_init_changed(vcpu, init))
1279                 return -EINVAL;
1280
1281         return kvm_reset_vcpu(vcpu);
1282 }
1283
1284 static int kvm_arch_vcpu_ioctl_vcpu_init(struct kvm_vcpu *vcpu,
1285                                          struct kvm_vcpu_init *init)
1286 {
1287         bool power_off = false;
1288         int ret;
1289
1290         /*
1291          * Treat the power-off vCPU feature as ephemeral. Clear the bit to avoid
1292          * reflecting it in the finalized feature set, thus limiting its scope
1293          * to a single KVM_ARM_VCPU_INIT call.
1294          */
1295         if (init->features[0] & BIT(KVM_ARM_VCPU_POWER_OFF)) {
1296                 init->features[0] &= ~BIT(KVM_ARM_VCPU_POWER_OFF);
1297                 power_off = true;
1298         }
1299
1300         ret = kvm_vcpu_set_target(vcpu, init);
1301         if (ret)
1302                 return ret;
1303
1304         /*
1305          * Ensure a rebooted VM will fault in RAM pages and detect if the
1306          * guest MMU is turned off and flush the caches as needed.
1307          *
1308          * S2FWB enforces all memory accesses to RAM being cacheable,
1309          * ensuring that the data side is always coherent. We still
1310          * need to invalidate the I-cache though, as FWB does *not*
1311          * imply CTR_EL0.DIC.
1312          */
1313         if (vcpu_has_run_once(vcpu)) {
1314                 if (!cpus_have_final_cap(ARM64_HAS_STAGE2_FWB))
1315                         stage2_unmap_vm(vcpu->kvm);
1316                 else
1317                         icache_inval_all_pou();
1318         }
1319
1320         vcpu_reset_hcr(vcpu);
1321         vcpu->arch.cptr_el2 = kvm_get_reset_cptr_el2(vcpu);
1322
1323         /*
1324          * Handle the "start in power-off" case.
1325          */
1326         spin_lock(&vcpu->arch.mp_state_lock);
1327
1328         if (power_off)
1329                 __kvm_arm_vcpu_power_off(vcpu);
1330         else
1331                 WRITE_ONCE(vcpu->arch.mp_state.mp_state, KVM_MP_STATE_RUNNABLE);
1332
1333         spin_unlock(&vcpu->arch.mp_state_lock);
1334
1335         return 0;
1336 }
1337
1338 static int kvm_arm_vcpu_set_attr(struct kvm_vcpu *vcpu,
1339                                  struct kvm_device_attr *attr)
1340 {
1341         int ret = -ENXIO;
1342
1343         switch (attr->group) {
1344         default:
1345                 ret = kvm_arm_vcpu_arch_set_attr(vcpu, attr);
1346                 break;
1347         }
1348
1349         return ret;
1350 }
1351
1352 static int kvm_arm_vcpu_get_attr(struct kvm_vcpu *vcpu,
1353                                  struct kvm_device_attr *attr)
1354 {
1355         int ret = -ENXIO;
1356
1357         switch (attr->group) {
1358         default:
1359                 ret = kvm_arm_vcpu_arch_get_attr(vcpu, attr);
1360                 break;
1361         }
1362
1363         return ret;
1364 }
1365
1366 static int kvm_arm_vcpu_has_attr(struct kvm_vcpu *vcpu,
1367                                  struct kvm_device_attr *attr)
1368 {
1369         int ret = -ENXIO;
1370
1371         switch (attr->group) {
1372         default:
1373                 ret = kvm_arm_vcpu_arch_has_attr(vcpu, attr);
1374                 break;
1375         }
1376
1377         return ret;
1378 }
1379
1380 static int kvm_arm_vcpu_get_events(struct kvm_vcpu *vcpu,
1381                                    struct kvm_vcpu_events *events)
1382 {
1383         memset(events, 0, sizeof(*events));
1384
1385         return __kvm_arm_vcpu_get_events(vcpu, events);
1386 }
1387
1388 static int kvm_arm_vcpu_set_events(struct kvm_vcpu *vcpu,
1389                                    struct kvm_vcpu_events *events)
1390 {
1391         int i;
1392
1393         /* check whether the reserved field is zero */
1394         for (i = 0; i < ARRAY_SIZE(events->reserved); i++)
1395                 if (events->reserved[i])
1396                         return -EINVAL;
1397
1398         /* check whether the pad field is zero */
1399         for (i = 0; i < ARRAY_SIZE(events->exception.pad); i++)
1400                 if (events->exception.pad[i])
1401                         return -EINVAL;
1402
1403         return __kvm_arm_vcpu_set_events(vcpu, events);
1404 }
1405
1406 long kvm_arch_vcpu_ioctl(struct file *filp,
1407                          unsigned int ioctl, unsigned long arg)
1408 {
1409         struct kvm_vcpu *vcpu = filp->private_data;
1410         void __user *argp = (void __user *)arg;
1411         struct kvm_device_attr attr;
1412         long r;
1413
1414         switch (ioctl) {
1415         case KVM_ARM_VCPU_INIT: {
1416                 struct kvm_vcpu_init init;
1417
1418                 r = -EFAULT;
1419                 if (copy_from_user(&init, argp, sizeof(init)))
1420                         break;
1421
1422                 r = kvm_arch_vcpu_ioctl_vcpu_init(vcpu, &init);
1423                 break;
1424         }
1425         case KVM_SET_ONE_REG:
1426         case KVM_GET_ONE_REG: {
1427                 struct kvm_one_reg reg;
1428
1429                 r = -ENOEXEC;
1430                 if (unlikely(!kvm_vcpu_initialized(vcpu)))
1431                         break;
1432
1433                 r = -EFAULT;
1434                 if (copy_from_user(&reg, argp, sizeof(reg)))
1435                         break;
1436
1437                 /*
1438                  * We could owe a reset due to PSCI. Handle the pending reset
1439                  * here to ensure userspace register accesses are ordered after
1440                  * the reset.
1441                  */
1442                 if (kvm_check_request(KVM_REQ_VCPU_RESET, vcpu))
1443                         kvm_reset_vcpu(vcpu);
1444
1445                 if (ioctl == KVM_SET_ONE_REG)
1446                         r = kvm_arm_set_reg(vcpu, &reg);
1447                 else
1448                         r = kvm_arm_get_reg(vcpu, &reg);
1449                 break;
1450         }
1451         case KVM_GET_REG_LIST: {
1452                 struct kvm_reg_list __user *user_list = argp;
1453                 struct kvm_reg_list reg_list;
1454                 unsigned n;
1455
1456                 r = -ENOEXEC;
1457                 if (unlikely(!kvm_vcpu_initialized(vcpu)))
1458                         break;
1459
1460                 r = -EPERM;
1461                 if (!kvm_arm_vcpu_is_finalized(vcpu))
1462                         break;
1463
1464                 r = -EFAULT;
1465                 if (copy_from_user(&reg_list, user_list, sizeof(reg_list)))
1466                         break;
1467                 n = reg_list.n;
1468                 reg_list.n = kvm_arm_num_regs(vcpu);
1469                 if (copy_to_user(user_list, &reg_list, sizeof(reg_list)))
1470                         break;
1471                 r = -E2BIG;
1472                 if (n < reg_list.n)
1473                         break;
1474                 r = kvm_arm_copy_reg_indices(vcpu, user_list->reg);
1475                 break;
1476         }
1477         case KVM_SET_DEVICE_ATTR: {
1478                 r = -EFAULT;
1479                 if (copy_from_user(&attr, argp, sizeof(attr)))
1480                         break;
1481                 r = kvm_arm_vcpu_set_attr(vcpu, &attr);
1482                 break;
1483         }
1484         case KVM_GET_DEVICE_ATTR: {
1485                 r = -EFAULT;
1486                 if (copy_from_user(&attr, argp, sizeof(attr)))
1487                         break;
1488                 r = kvm_arm_vcpu_get_attr(vcpu, &attr);
1489                 break;
1490         }
1491         case KVM_HAS_DEVICE_ATTR: {
1492                 r = -EFAULT;
1493                 if (copy_from_user(&attr, argp, sizeof(attr)))
1494                         break;
1495                 r = kvm_arm_vcpu_has_attr(vcpu, &attr);
1496                 break;
1497         }
1498         case KVM_GET_VCPU_EVENTS: {
1499                 struct kvm_vcpu_events events;
1500
1501                 if (kvm_arm_vcpu_get_events(vcpu, &events))
1502                         return -EINVAL;
1503
1504                 if (copy_to_user(argp, &events, sizeof(events)))
1505                         return -EFAULT;
1506
1507                 return 0;
1508         }
1509         case KVM_SET_VCPU_EVENTS: {
1510                 struct kvm_vcpu_events events;
1511
1512                 if (copy_from_user(&events, argp, sizeof(events)))
1513                         return -EFAULT;
1514
1515                 return kvm_arm_vcpu_set_events(vcpu, &events);
1516         }
1517         case KVM_ARM_VCPU_FINALIZE: {
1518                 int what;
1519
1520                 if (!kvm_vcpu_initialized(vcpu))
1521                         return -ENOEXEC;
1522
1523                 if (get_user(what, (const int __user *)argp))
1524                         return -EFAULT;
1525
1526                 return kvm_arm_vcpu_finalize(vcpu, what);
1527         }
1528         default:
1529                 r = -EINVAL;
1530         }
1531
1532         return r;
1533 }
1534
1535 void kvm_arch_sync_dirty_log(struct kvm *kvm, struct kvm_memory_slot *memslot)
1536 {
1537
1538 }
1539
1540 static int kvm_vm_ioctl_set_device_addr(struct kvm *kvm,
1541                                         struct kvm_arm_device_addr *dev_addr)
1542 {
1543         switch (FIELD_GET(KVM_ARM_DEVICE_ID_MASK, dev_addr->id)) {
1544         case KVM_ARM_DEVICE_VGIC_V2:
1545                 if (!vgic_present)
1546                         return -ENXIO;
1547                 return kvm_set_legacy_vgic_v2_addr(kvm, dev_addr);
1548         default:
1549                 return -ENODEV;
1550         }
1551 }
1552
1553 static int kvm_vm_has_attr(struct kvm *kvm, struct kvm_device_attr *attr)
1554 {
1555         switch (attr->group) {
1556         case KVM_ARM_VM_SMCCC_CTRL:
1557                 return kvm_vm_smccc_has_attr(kvm, attr);
1558         default:
1559                 return -ENXIO;
1560         }
1561 }
1562
1563 static int kvm_vm_set_attr(struct kvm *kvm, struct kvm_device_attr *attr)
1564 {
1565         switch (attr->group) {
1566         case KVM_ARM_VM_SMCCC_CTRL:
1567                 return kvm_vm_smccc_set_attr(kvm, attr);
1568         default:
1569                 return -ENXIO;
1570         }
1571 }
1572
1573 int kvm_arch_vm_ioctl(struct file *filp, unsigned int ioctl, unsigned long arg)
1574 {
1575         struct kvm *kvm = filp->private_data;
1576         void __user *argp = (void __user *)arg;
1577         struct kvm_device_attr attr;
1578
1579         switch (ioctl) {
1580         case KVM_CREATE_IRQCHIP: {
1581                 int ret;
1582                 if (!vgic_present)
1583                         return -ENXIO;
1584                 mutex_lock(&kvm->lock);
1585                 ret = kvm_vgic_create(kvm, KVM_DEV_TYPE_ARM_VGIC_V2);
1586                 mutex_unlock(&kvm->lock);
1587                 return ret;
1588         }
1589         case KVM_ARM_SET_DEVICE_ADDR: {
1590                 struct kvm_arm_device_addr dev_addr;
1591
1592                 if (copy_from_user(&dev_addr, argp, sizeof(dev_addr)))
1593                         return -EFAULT;
1594                 return kvm_vm_ioctl_set_device_addr(kvm, &dev_addr);
1595         }
1596         case KVM_ARM_PREFERRED_TARGET: {
1597                 struct kvm_vcpu_init init = {
1598                         .target = KVM_ARM_TARGET_GENERIC_V8,
1599                 };
1600
1601                 if (copy_to_user(argp, &init, sizeof(init)))
1602                         return -EFAULT;
1603
1604                 return 0;
1605         }
1606         case KVM_ARM_MTE_COPY_TAGS: {
1607                 struct kvm_arm_copy_mte_tags copy_tags;
1608
1609                 if (copy_from_user(&copy_tags, argp, sizeof(copy_tags)))
1610                         return -EFAULT;
1611                 return kvm_vm_ioctl_mte_copy_tags(kvm, &copy_tags);
1612         }
1613         case KVM_ARM_SET_COUNTER_OFFSET: {
1614                 struct kvm_arm_counter_offset offset;
1615
1616                 if (copy_from_user(&offset, argp, sizeof(offset)))
1617                         return -EFAULT;
1618                 return kvm_vm_ioctl_set_counter_offset(kvm, &offset);
1619         }
1620         case KVM_HAS_DEVICE_ATTR: {
1621                 if (copy_from_user(&attr, argp, sizeof(attr)))
1622                         return -EFAULT;
1623
1624                 return kvm_vm_has_attr(kvm, &attr);
1625         }
1626         case KVM_SET_DEVICE_ATTR: {
1627                 if (copy_from_user(&attr, argp, sizeof(attr)))
1628                         return -EFAULT;
1629
1630                 return kvm_vm_set_attr(kvm, &attr);
1631         }
1632         default:
1633                 return -EINVAL;
1634         }
1635 }
1636
1637 /* unlocks vcpus from @vcpu_lock_idx and smaller */
1638 static void unlock_vcpus(struct kvm *kvm, int vcpu_lock_idx)
1639 {
1640         struct kvm_vcpu *tmp_vcpu;
1641
1642         for (; vcpu_lock_idx >= 0; vcpu_lock_idx--) {
1643                 tmp_vcpu = kvm_get_vcpu(kvm, vcpu_lock_idx);
1644                 mutex_unlock(&tmp_vcpu->mutex);
1645         }
1646 }
1647
1648 void unlock_all_vcpus(struct kvm *kvm)
1649 {
1650         lockdep_assert_held(&kvm->lock);
1651
1652         unlock_vcpus(kvm, atomic_read(&kvm->online_vcpus) - 1);
1653 }
1654
1655 /* Returns true if all vcpus were locked, false otherwise */
1656 bool lock_all_vcpus(struct kvm *kvm)
1657 {
1658         struct kvm_vcpu *tmp_vcpu;
1659         unsigned long c;
1660
1661         lockdep_assert_held(&kvm->lock);
1662
1663         /*
1664          * Any time a vcpu is in an ioctl (including running), the
1665          * core KVM code tries to grab the vcpu->mutex.
1666          *
1667          * By grabbing the vcpu->mutex of all VCPUs we ensure that no
1668          * other VCPUs can fiddle with the state while we access it.
1669          */
1670         kvm_for_each_vcpu(c, tmp_vcpu, kvm) {
1671                 if (!mutex_trylock(&tmp_vcpu->mutex)) {
1672                         unlock_vcpus(kvm, c - 1);
1673                         return false;
1674                 }
1675         }
1676
1677         return true;
1678 }
1679
1680 static unsigned long nvhe_percpu_size(void)
1681 {
1682         return (unsigned long)CHOOSE_NVHE_SYM(__per_cpu_end) -
1683                 (unsigned long)CHOOSE_NVHE_SYM(__per_cpu_start);
1684 }
1685
1686 static unsigned long nvhe_percpu_order(void)
1687 {
1688         unsigned long size = nvhe_percpu_size();
1689
1690         return size ? get_order(size) : 0;
1691 }
1692
1693 /* A lookup table holding the hypervisor VA for each vector slot */
1694 static void *hyp_spectre_vector_selector[BP_HARDEN_EL2_SLOTS];
1695
1696 static void kvm_init_vector_slot(void *base, enum arm64_hyp_spectre_vector slot)
1697 {
1698         hyp_spectre_vector_selector[slot] = __kvm_vector_slot2addr(base, slot);
1699 }
1700
1701 static int kvm_init_vector_slots(void)
1702 {
1703         int err;
1704         void *base;
1705
1706         base = kern_hyp_va(kvm_ksym_ref(__kvm_hyp_vector));
1707         kvm_init_vector_slot(base, HYP_VECTOR_DIRECT);
1708
1709         base = kern_hyp_va(kvm_ksym_ref(__bp_harden_hyp_vecs));
1710         kvm_init_vector_slot(base, HYP_VECTOR_SPECTRE_DIRECT);
1711
1712         if (kvm_system_needs_idmapped_vectors() &&
1713             !is_protected_kvm_enabled()) {
1714                 err = create_hyp_exec_mappings(__pa_symbol(__bp_harden_hyp_vecs),
1715                                                __BP_HARDEN_HYP_VECS_SZ, &base);
1716                 if (err)
1717                         return err;
1718         }
1719
1720         kvm_init_vector_slot(base, HYP_VECTOR_INDIRECT);
1721         kvm_init_vector_slot(base, HYP_VECTOR_SPECTRE_INDIRECT);
1722         return 0;
1723 }
1724
1725 static void __init cpu_prepare_hyp_mode(int cpu, u32 hyp_va_bits)
1726 {
1727         struct kvm_nvhe_init_params *params = per_cpu_ptr_nvhe_sym(kvm_init_params, cpu);
1728         unsigned long tcr;
1729
1730         /*
1731          * Calculate the raw per-cpu offset without a translation from the
1732          * kernel's mapping to the linear mapping, and store it in tpidr_el2
1733          * so that we can use adr_l to access per-cpu variables in EL2.
1734          * Also drop the KASAN tag which gets in the way...
1735          */
1736         params->tpidr_el2 = (unsigned long)kasan_reset_tag(per_cpu_ptr_nvhe_sym(__per_cpu_start, cpu)) -
1737                             (unsigned long)kvm_ksym_ref(CHOOSE_NVHE_SYM(__per_cpu_start));
1738
1739         params->mair_el2 = read_sysreg(mair_el1);
1740
1741         tcr = read_sysreg(tcr_el1);
1742         if (cpus_have_final_cap(ARM64_KVM_HVHE)) {
1743                 tcr |= TCR_EPD1_MASK;
1744         } else {
1745                 tcr &= TCR_EL2_MASK;
1746                 tcr |= TCR_EL2_RES1;
1747         }
1748         tcr &= ~TCR_T0SZ_MASK;
1749         tcr |= TCR_T0SZ(hyp_va_bits);
1750         params->tcr_el2 = tcr;
1751
1752         params->pgd_pa = kvm_mmu_get_httbr();
1753         if (is_protected_kvm_enabled())
1754                 params->hcr_el2 = HCR_HOST_NVHE_PROTECTED_FLAGS;
1755         else
1756                 params->hcr_el2 = HCR_HOST_NVHE_FLAGS;
1757         if (cpus_have_final_cap(ARM64_KVM_HVHE))
1758                 params->hcr_el2 |= HCR_E2H;
1759         params->vttbr = params->vtcr = 0;
1760
1761         /*
1762          * Flush the init params from the data cache because the struct will
1763          * be read while the MMU is off.
1764          */
1765         kvm_flush_dcache_to_poc(params, sizeof(*params));
1766 }
1767
1768 static void hyp_install_host_vector(void)
1769 {
1770         struct kvm_nvhe_init_params *params;
1771         struct arm_smccc_res res;
1772
1773         /* Switch from the HYP stub to our own HYP init vector */
1774         __hyp_set_vectors(kvm_get_idmap_vector());
1775
1776         /*
1777          * Call initialization code, and switch to the full blown HYP code.
1778          * If the cpucaps haven't been finalized yet, something has gone very
1779          * wrong, and hyp will crash and burn when it uses any
1780          * cpus_have_const_cap() wrapper.
1781          */
1782         BUG_ON(!system_capabilities_finalized());
1783         params = this_cpu_ptr_nvhe_sym(kvm_init_params);
1784         arm_smccc_1_1_hvc(KVM_HOST_SMCCC_FUNC(__kvm_hyp_init), virt_to_phys(params), &res);
1785         WARN_ON(res.a0 != SMCCC_RET_SUCCESS);
1786 }
1787
1788 static void cpu_init_hyp_mode(void)
1789 {
1790         hyp_install_host_vector();
1791
1792         /*
1793          * Disabling SSBD on a non-VHE system requires us to enable SSBS
1794          * at EL2.
1795          */
1796         if (this_cpu_has_cap(ARM64_SSBS) &&
1797             arm64_get_spectre_v4_state() == SPECTRE_VULNERABLE) {
1798                 kvm_call_hyp_nvhe(__kvm_enable_ssbs);
1799         }
1800 }
1801
1802 static void cpu_hyp_reset(void)
1803 {
1804         if (!is_kernel_in_hyp_mode())
1805                 __hyp_reset_vectors();
1806 }
1807
1808 /*
1809  * EL2 vectors can be mapped and rerouted in a number of ways,
1810  * depending on the kernel configuration and CPU present:
1811  *
1812  * - If the CPU is affected by Spectre-v2, the hardening sequence is
1813  *   placed in one of the vector slots, which is executed before jumping
1814  *   to the real vectors.
1815  *
1816  * - If the CPU also has the ARM64_SPECTRE_V3A cap, the slot
1817  *   containing the hardening sequence is mapped next to the idmap page,
1818  *   and executed before jumping to the real vectors.
1819  *
1820  * - If the CPU only has the ARM64_SPECTRE_V3A cap, then an
1821  *   empty slot is selected, mapped next to the idmap page, and
1822  *   executed before jumping to the real vectors.
1823  *
1824  * Note that ARM64_SPECTRE_V3A is somewhat incompatible with
1825  * VHE, as we don't have hypervisor-specific mappings. If the system
1826  * is VHE and yet selects this capability, it will be ignored.
1827  */
1828 static void cpu_set_hyp_vector(void)
1829 {
1830         struct bp_hardening_data *data = this_cpu_ptr(&bp_hardening_data);
1831         void *vector = hyp_spectre_vector_selector[data->slot];
1832
1833         if (!is_protected_kvm_enabled())
1834                 *this_cpu_ptr_hyp_sym(kvm_hyp_vector) = (unsigned long)vector;
1835         else
1836                 kvm_call_hyp_nvhe(__pkvm_cpu_set_vector, data->slot);
1837 }
1838
1839 static void cpu_hyp_init_context(void)
1840 {
1841         kvm_init_host_cpu_context(&this_cpu_ptr_hyp_sym(kvm_host_data)->host_ctxt);
1842
1843         if (!is_kernel_in_hyp_mode())
1844                 cpu_init_hyp_mode();
1845 }
1846
1847 static void cpu_hyp_init_features(void)
1848 {
1849         cpu_set_hyp_vector();
1850         kvm_arm_init_debug();
1851
1852         if (is_kernel_in_hyp_mode())
1853                 kvm_timer_init_vhe();
1854
1855         if (vgic_present)
1856                 kvm_vgic_init_cpu_hardware();
1857 }
1858
1859 static void cpu_hyp_reinit(void)
1860 {
1861         cpu_hyp_reset();
1862         cpu_hyp_init_context();
1863         cpu_hyp_init_features();
1864 }
1865
1866 static void cpu_hyp_init(void *discard)
1867 {
1868         if (!__this_cpu_read(kvm_hyp_initialized)) {
1869                 cpu_hyp_reinit();
1870                 __this_cpu_write(kvm_hyp_initialized, 1);
1871         }
1872 }
1873
1874 static void cpu_hyp_uninit(void *discard)
1875 {
1876         if (__this_cpu_read(kvm_hyp_initialized)) {
1877                 cpu_hyp_reset();
1878                 __this_cpu_write(kvm_hyp_initialized, 0);
1879         }
1880 }
1881
1882 int kvm_arch_hardware_enable(void)
1883 {
1884         /*
1885          * Most calls to this function are made with migration
1886          * disabled, but not with preemption disabled. The former is
1887          * enough to ensure correctness, but most of the helpers
1888          * expect the later and will throw a tantrum otherwise.
1889          */
1890         preempt_disable();
1891
1892         cpu_hyp_init(NULL);
1893
1894         kvm_vgic_cpu_up();
1895         kvm_timer_cpu_up();
1896
1897         preempt_enable();
1898
1899         return 0;
1900 }
1901
1902 void kvm_arch_hardware_disable(void)
1903 {
1904         kvm_timer_cpu_down();
1905         kvm_vgic_cpu_down();
1906
1907         if (!is_protected_kvm_enabled())
1908                 cpu_hyp_uninit(NULL);
1909 }
1910
1911 #ifdef CONFIG_CPU_PM
1912 static int hyp_init_cpu_pm_notifier(struct notifier_block *self,
1913                                     unsigned long cmd,
1914                                     void *v)
1915 {
1916         /*
1917          * kvm_hyp_initialized is left with its old value over
1918          * PM_ENTER->PM_EXIT. It is used to indicate PM_EXIT should
1919          * re-enable hyp.
1920          */
1921         switch (cmd) {
1922         case CPU_PM_ENTER:
1923                 if (__this_cpu_read(kvm_hyp_initialized))
1924                         /*
1925                          * don't update kvm_hyp_initialized here
1926                          * so that the hyp will be re-enabled
1927                          * when we resume. See below.
1928                          */
1929                         cpu_hyp_reset();
1930
1931                 return NOTIFY_OK;
1932         case CPU_PM_ENTER_FAILED:
1933         case CPU_PM_EXIT:
1934                 if (__this_cpu_read(kvm_hyp_initialized))
1935                         /* The hyp was enabled before suspend. */
1936                         cpu_hyp_reinit();
1937
1938                 return NOTIFY_OK;
1939
1940         default:
1941                 return NOTIFY_DONE;
1942         }
1943 }
1944
1945 static struct notifier_block hyp_init_cpu_pm_nb = {
1946         .notifier_call = hyp_init_cpu_pm_notifier,
1947 };
1948
1949 static void __init hyp_cpu_pm_init(void)
1950 {
1951         if (!is_protected_kvm_enabled())
1952                 cpu_pm_register_notifier(&hyp_init_cpu_pm_nb);
1953 }
1954 static void __init hyp_cpu_pm_exit(void)
1955 {
1956         if (!is_protected_kvm_enabled())
1957                 cpu_pm_unregister_notifier(&hyp_init_cpu_pm_nb);
1958 }
1959 #else
1960 static inline void __init hyp_cpu_pm_init(void)
1961 {
1962 }
1963 static inline void __init hyp_cpu_pm_exit(void)
1964 {
1965 }
1966 #endif
1967
1968 static void __init init_cpu_logical_map(void)
1969 {
1970         unsigned int cpu;
1971
1972         /*
1973          * Copy the MPIDR <-> logical CPU ID mapping to hyp.
1974          * Only copy the set of online CPUs whose features have been checked
1975          * against the finalized system capabilities. The hypervisor will not
1976          * allow any other CPUs from the `possible` set to boot.
1977          */
1978         for_each_online_cpu(cpu)
1979                 hyp_cpu_logical_map[cpu] = cpu_logical_map(cpu);
1980 }
1981
1982 #define init_psci_0_1_impl_state(config, what)  \
1983         config.psci_0_1_ ## what ## _implemented = psci_ops.what
1984
1985 static bool __init init_psci_relay(void)
1986 {
1987         /*
1988          * If PSCI has not been initialized, protected KVM cannot install
1989          * itself on newly booted CPUs.
1990          */
1991         if (!psci_ops.get_version) {
1992                 kvm_err("Cannot initialize protected mode without PSCI\n");
1993                 return false;
1994         }
1995
1996         kvm_host_psci_config.version = psci_ops.get_version();
1997         kvm_host_psci_config.smccc_version = arm_smccc_get_version();
1998
1999         if (kvm_host_psci_config.version == PSCI_VERSION(0, 1)) {
2000                 kvm_host_psci_config.function_ids_0_1 = get_psci_0_1_function_ids();
2001                 init_psci_0_1_impl_state(kvm_host_psci_config, cpu_suspend);
2002                 init_psci_0_1_impl_state(kvm_host_psci_config, cpu_on);
2003                 init_psci_0_1_impl_state(kvm_host_psci_config, cpu_off);
2004                 init_psci_0_1_impl_state(kvm_host_psci_config, migrate);
2005         }
2006         return true;
2007 }
2008
2009 static int __init init_subsystems(void)
2010 {
2011         int err = 0;
2012
2013         /*
2014          * Enable hardware so that subsystem initialisation can access EL2.
2015          */
2016         on_each_cpu(cpu_hyp_init, NULL, 1);
2017
2018         /*
2019          * Register CPU lower-power notifier
2020          */
2021         hyp_cpu_pm_init();
2022
2023         /*
2024          * Init HYP view of VGIC
2025          */
2026         err = kvm_vgic_hyp_init();
2027         switch (err) {
2028         case 0:
2029                 vgic_present = true;
2030                 break;
2031         case -ENODEV:
2032         case -ENXIO:
2033                 vgic_present = false;
2034                 err = 0;
2035                 break;
2036         default:
2037                 goto out;
2038         }
2039
2040         /*
2041          * Init HYP architected timer support
2042          */
2043         err = kvm_timer_hyp_init(vgic_present);
2044         if (err)
2045                 goto out;
2046
2047         kvm_register_perf_callbacks(NULL);
2048
2049 out:
2050         if (err)
2051                 hyp_cpu_pm_exit();
2052
2053         if (err || !is_protected_kvm_enabled())
2054                 on_each_cpu(cpu_hyp_uninit, NULL, 1);
2055
2056         return err;
2057 }
2058
2059 static void __init teardown_subsystems(void)
2060 {
2061         kvm_unregister_perf_callbacks();
2062         hyp_cpu_pm_exit();
2063 }
2064
2065 static void __init teardown_hyp_mode(void)
2066 {
2067         int cpu;
2068
2069         free_hyp_pgds();
2070         for_each_possible_cpu(cpu) {
2071                 free_page(per_cpu(kvm_arm_hyp_stack_page, cpu));
2072                 free_pages(kvm_nvhe_sym(kvm_arm_hyp_percpu_base)[cpu], nvhe_percpu_order());
2073         }
2074 }
2075
2076 static int __init do_pkvm_init(u32 hyp_va_bits)
2077 {
2078         void *per_cpu_base = kvm_ksym_ref(kvm_nvhe_sym(kvm_arm_hyp_percpu_base));
2079         int ret;
2080
2081         preempt_disable();
2082         cpu_hyp_init_context();
2083         ret = kvm_call_hyp_nvhe(__pkvm_init, hyp_mem_base, hyp_mem_size,
2084                                 num_possible_cpus(), kern_hyp_va(per_cpu_base),
2085                                 hyp_va_bits);
2086         cpu_hyp_init_features();
2087
2088         /*
2089          * The stub hypercalls are now disabled, so set our local flag to
2090          * prevent a later re-init attempt in kvm_arch_hardware_enable().
2091          */
2092         __this_cpu_write(kvm_hyp_initialized, 1);
2093         preempt_enable();
2094
2095         return ret;
2096 }
2097
2098 static u64 get_hyp_id_aa64pfr0_el1(void)
2099 {
2100         /*
2101          * Track whether the system isn't affected by spectre/meltdown in the
2102          * hypervisor's view of id_aa64pfr0_el1, used for protected VMs.
2103          * Although this is per-CPU, we make it global for simplicity, e.g., not
2104          * to have to worry about vcpu migration.
2105          *
2106          * Unlike for non-protected VMs, userspace cannot override this for
2107          * protected VMs.
2108          */
2109         u64 val = read_sanitised_ftr_reg(SYS_ID_AA64PFR0_EL1);
2110
2111         val &= ~(ARM64_FEATURE_MASK(ID_AA64PFR0_EL1_CSV2) |
2112                  ARM64_FEATURE_MASK(ID_AA64PFR0_EL1_CSV3));
2113
2114         val |= FIELD_PREP(ARM64_FEATURE_MASK(ID_AA64PFR0_EL1_CSV2),
2115                           arm64_get_spectre_v2_state() == SPECTRE_UNAFFECTED);
2116         val |= FIELD_PREP(ARM64_FEATURE_MASK(ID_AA64PFR0_EL1_CSV3),
2117                           arm64_get_meltdown_state() == SPECTRE_UNAFFECTED);
2118
2119         return val;
2120 }
2121
2122 static void kvm_hyp_init_symbols(void)
2123 {
2124         kvm_nvhe_sym(id_aa64pfr0_el1_sys_val) = get_hyp_id_aa64pfr0_el1();
2125         kvm_nvhe_sym(id_aa64pfr1_el1_sys_val) = read_sanitised_ftr_reg(SYS_ID_AA64PFR1_EL1);
2126         kvm_nvhe_sym(id_aa64isar0_el1_sys_val) = read_sanitised_ftr_reg(SYS_ID_AA64ISAR0_EL1);
2127         kvm_nvhe_sym(id_aa64isar1_el1_sys_val) = read_sanitised_ftr_reg(SYS_ID_AA64ISAR1_EL1);
2128         kvm_nvhe_sym(id_aa64isar2_el1_sys_val) = read_sanitised_ftr_reg(SYS_ID_AA64ISAR2_EL1);
2129         kvm_nvhe_sym(id_aa64mmfr0_el1_sys_val) = read_sanitised_ftr_reg(SYS_ID_AA64MMFR0_EL1);
2130         kvm_nvhe_sym(id_aa64mmfr1_el1_sys_val) = read_sanitised_ftr_reg(SYS_ID_AA64MMFR1_EL1);
2131         kvm_nvhe_sym(id_aa64mmfr2_el1_sys_val) = read_sanitised_ftr_reg(SYS_ID_AA64MMFR2_EL1);
2132         kvm_nvhe_sym(id_aa64smfr0_el1_sys_val) = read_sanitised_ftr_reg(SYS_ID_AA64SMFR0_EL1);
2133         kvm_nvhe_sym(__icache_flags) = __icache_flags;
2134         kvm_nvhe_sym(kvm_arm_vmid_bits) = kvm_arm_vmid_bits;
2135 }
2136
2137 static int __init kvm_hyp_init_protection(u32 hyp_va_bits)
2138 {
2139         void *addr = phys_to_virt(hyp_mem_base);
2140         int ret;
2141
2142         ret = create_hyp_mappings(addr, addr + hyp_mem_size, PAGE_HYP);
2143         if (ret)
2144                 return ret;
2145
2146         ret = do_pkvm_init(hyp_va_bits);
2147         if (ret)
2148                 return ret;
2149
2150         free_hyp_pgds();
2151
2152         return 0;
2153 }
2154
2155 static void pkvm_hyp_init_ptrauth(void)
2156 {
2157         struct kvm_cpu_context *hyp_ctxt;
2158         int cpu;
2159
2160         for_each_possible_cpu(cpu) {
2161                 hyp_ctxt = per_cpu_ptr_nvhe_sym(kvm_hyp_ctxt, cpu);
2162                 hyp_ctxt->sys_regs[APIAKEYLO_EL1] = get_random_long();
2163                 hyp_ctxt->sys_regs[APIAKEYHI_EL1] = get_random_long();
2164                 hyp_ctxt->sys_regs[APIBKEYLO_EL1] = get_random_long();
2165                 hyp_ctxt->sys_regs[APIBKEYHI_EL1] = get_random_long();
2166                 hyp_ctxt->sys_regs[APDAKEYLO_EL1] = get_random_long();
2167                 hyp_ctxt->sys_regs[APDAKEYHI_EL1] = get_random_long();
2168                 hyp_ctxt->sys_regs[APDBKEYLO_EL1] = get_random_long();
2169                 hyp_ctxt->sys_regs[APDBKEYHI_EL1] = get_random_long();
2170                 hyp_ctxt->sys_regs[APGAKEYLO_EL1] = get_random_long();
2171                 hyp_ctxt->sys_regs[APGAKEYHI_EL1] = get_random_long();
2172         }
2173 }
2174
2175 /* Inits Hyp-mode on all online CPUs */
2176 static int __init init_hyp_mode(void)
2177 {
2178         u32 hyp_va_bits;
2179         int cpu;
2180         int err = -ENOMEM;
2181
2182         /*
2183          * The protected Hyp-mode cannot be initialized if the memory pool
2184          * allocation has failed.
2185          */
2186         if (is_protected_kvm_enabled() && !hyp_mem_base)
2187                 goto out_err;
2188
2189         /*
2190          * Allocate Hyp PGD and setup Hyp identity mapping
2191          */
2192         err = kvm_mmu_init(&hyp_va_bits);
2193         if (err)
2194                 goto out_err;
2195
2196         /*
2197          * Allocate stack pages for Hypervisor-mode
2198          */
2199         for_each_possible_cpu(cpu) {
2200                 unsigned long stack_page;
2201
2202                 stack_page = __get_free_page(GFP_KERNEL);
2203                 if (!stack_page) {
2204                         err = -ENOMEM;
2205                         goto out_err;
2206                 }
2207
2208                 per_cpu(kvm_arm_hyp_stack_page, cpu) = stack_page;
2209         }
2210
2211         /*
2212          * Allocate and initialize pages for Hypervisor-mode percpu regions.
2213          */
2214         for_each_possible_cpu(cpu) {
2215                 struct page *page;
2216                 void *page_addr;
2217
2218                 page = alloc_pages(GFP_KERNEL, nvhe_percpu_order());
2219                 if (!page) {
2220                         err = -ENOMEM;
2221                         goto out_err;
2222                 }
2223
2224                 page_addr = page_address(page);
2225                 memcpy(page_addr, CHOOSE_NVHE_SYM(__per_cpu_start), nvhe_percpu_size());
2226                 kvm_nvhe_sym(kvm_arm_hyp_percpu_base)[cpu] = (unsigned long)page_addr;
2227         }
2228
2229         /*
2230          * Map the Hyp-code called directly from the host
2231          */
2232         err = create_hyp_mappings(kvm_ksym_ref(__hyp_text_start),
2233                                   kvm_ksym_ref(__hyp_text_end), PAGE_HYP_EXEC);
2234         if (err) {
2235                 kvm_err("Cannot map world-switch code\n");
2236                 goto out_err;
2237         }
2238
2239         err = create_hyp_mappings(kvm_ksym_ref(__hyp_rodata_start),
2240                                   kvm_ksym_ref(__hyp_rodata_end), PAGE_HYP_RO);
2241         if (err) {
2242                 kvm_err("Cannot map .hyp.rodata section\n");
2243                 goto out_err;
2244         }
2245
2246         err = create_hyp_mappings(kvm_ksym_ref(__start_rodata),
2247                                   kvm_ksym_ref(__end_rodata), PAGE_HYP_RO);
2248         if (err) {
2249                 kvm_err("Cannot map rodata section\n");
2250                 goto out_err;
2251         }
2252
2253         /*
2254          * .hyp.bss is guaranteed to be placed at the beginning of the .bss
2255          * section thanks to an assertion in the linker script. Map it RW and
2256          * the rest of .bss RO.
2257          */
2258         err = create_hyp_mappings(kvm_ksym_ref(__hyp_bss_start),
2259                                   kvm_ksym_ref(__hyp_bss_end), PAGE_HYP);
2260         if (err) {
2261                 kvm_err("Cannot map hyp bss section: %d\n", err);
2262                 goto out_err;
2263         }
2264
2265         err = create_hyp_mappings(kvm_ksym_ref(__hyp_bss_end),
2266                                   kvm_ksym_ref(__bss_stop), PAGE_HYP_RO);
2267         if (err) {
2268                 kvm_err("Cannot map bss section\n");
2269                 goto out_err;
2270         }
2271
2272         /*
2273          * Map the Hyp stack pages
2274          */
2275         for_each_possible_cpu(cpu) {
2276                 struct kvm_nvhe_init_params *params = per_cpu_ptr_nvhe_sym(kvm_init_params, cpu);
2277                 char *stack_page = (char *)per_cpu(kvm_arm_hyp_stack_page, cpu);
2278
2279                 err = create_hyp_stack(__pa(stack_page), &params->stack_hyp_va);
2280                 if (err) {
2281                         kvm_err("Cannot map hyp stack\n");
2282                         goto out_err;
2283                 }
2284
2285                 /*
2286                  * Save the stack PA in nvhe_init_params. This will be needed
2287                  * to recreate the stack mapping in protected nVHE mode.
2288                  * __hyp_pa() won't do the right thing there, since the stack
2289                  * has been mapped in the flexible private VA space.
2290                  */
2291                 params->stack_pa = __pa(stack_page);
2292         }
2293
2294         for_each_possible_cpu(cpu) {
2295                 char *percpu_begin = (char *)kvm_nvhe_sym(kvm_arm_hyp_percpu_base)[cpu];
2296                 char *percpu_end = percpu_begin + nvhe_percpu_size();
2297
2298                 /* Map Hyp percpu pages */
2299                 err = create_hyp_mappings(percpu_begin, percpu_end, PAGE_HYP);
2300                 if (err) {
2301                         kvm_err("Cannot map hyp percpu region\n");
2302                         goto out_err;
2303                 }
2304
2305                 /* Prepare the CPU initialization parameters */
2306                 cpu_prepare_hyp_mode(cpu, hyp_va_bits);
2307         }
2308
2309         kvm_hyp_init_symbols();
2310
2311         if (is_protected_kvm_enabled()) {
2312                 if (IS_ENABLED(CONFIG_ARM64_PTR_AUTH_KERNEL) &&
2313                     cpus_have_const_cap(ARM64_HAS_ADDRESS_AUTH))
2314                         pkvm_hyp_init_ptrauth();
2315
2316                 init_cpu_logical_map();
2317
2318                 if (!init_psci_relay()) {
2319                         err = -ENODEV;
2320                         goto out_err;
2321                 }
2322
2323                 err = kvm_hyp_init_protection(hyp_va_bits);
2324                 if (err) {
2325                         kvm_err("Failed to init hyp memory protection\n");
2326                         goto out_err;
2327                 }
2328         }
2329
2330         return 0;
2331
2332 out_err:
2333         teardown_hyp_mode();
2334         kvm_err("error initializing Hyp mode: %d\n", err);
2335         return err;
2336 }
2337
2338 struct kvm_vcpu *kvm_mpidr_to_vcpu(struct kvm *kvm, unsigned long mpidr)
2339 {
2340         struct kvm_vcpu *vcpu;
2341         unsigned long i;
2342
2343         mpidr &= MPIDR_HWID_BITMASK;
2344         kvm_for_each_vcpu(i, vcpu, kvm) {
2345                 if (mpidr == kvm_vcpu_get_mpidr_aff(vcpu))
2346                         return vcpu;
2347         }
2348         return NULL;
2349 }
2350
2351 bool kvm_arch_irqchip_in_kernel(struct kvm *kvm)
2352 {
2353         return irqchip_in_kernel(kvm);
2354 }
2355
2356 bool kvm_arch_has_irq_bypass(void)
2357 {
2358         return true;
2359 }
2360
2361 int kvm_arch_irq_bypass_add_producer(struct irq_bypass_consumer *cons,
2362                                       struct irq_bypass_producer *prod)
2363 {
2364         struct kvm_kernel_irqfd *irqfd =
2365                 container_of(cons, struct kvm_kernel_irqfd, consumer);
2366
2367         return kvm_vgic_v4_set_forwarding(irqfd->kvm, prod->irq,
2368                                           &irqfd->irq_entry);
2369 }
2370 void kvm_arch_irq_bypass_del_producer(struct irq_bypass_consumer *cons,
2371                                       struct irq_bypass_producer *prod)
2372 {
2373         struct kvm_kernel_irqfd *irqfd =
2374                 container_of(cons, struct kvm_kernel_irqfd, consumer);
2375
2376         kvm_vgic_v4_unset_forwarding(irqfd->kvm, prod->irq,
2377                                      &irqfd->irq_entry);
2378 }
2379
2380 void kvm_arch_irq_bypass_stop(struct irq_bypass_consumer *cons)
2381 {
2382         struct kvm_kernel_irqfd *irqfd =
2383                 container_of(cons, struct kvm_kernel_irqfd, consumer);
2384
2385         kvm_arm_halt_guest(irqfd->kvm);
2386 }
2387
2388 void kvm_arch_irq_bypass_start(struct irq_bypass_consumer *cons)
2389 {
2390         struct kvm_kernel_irqfd *irqfd =
2391                 container_of(cons, struct kvm_kernel_irqfd, consumer);
2392
2393         kvm_arm_resume_guest(irqfd->kvm);
2394 }
2395
2396 /* Initialize Hyp-mode and memory mappings on all CPUs */
2397 static __init int kvm_arm_init(void)
2398 {
2399         int err;
2400         bool in_hyp_mode;
2401
2402         if (!is_hyp_mode_available()) {
2403                 kvm_info("HYP mode not available\n");
2404                 return -ENODEV;
2405         }
2406
2407         if (kvm_get_mode() == KVM_MODE_NONE) {
2408                 kvm_info("KVM disabled from command line\n");
2409                 return -ENODEV;
2410         }
2411
2412         err = kvm_sys_reg_table_init();
2413         if (err) {
2414                 kvm_info("Error initializing system register tables");
2415                 return err;
2416         }
2417
2418         in_hyp_mode = is_kernel_in_hyp_mode();
2419
2420         if (cpus_have_final_cap(ARM64_WORKAROUND_DEVICE_LOAD_ACQUIRE) ||
2421             cpus_have_final_cap(ARM64_WORKAROUND_1508412))
2422                 kvm_info("Guests without required CPU erratum workarounds can deadlock system!\n" \
2423                          "Only trusted guests should be used on this system.\n");
2424
2425         err = kvm_set_ipa_limit();
2426         if (err)
2427                 return err;
2428
2429         err = kvm_arm_init_sve();
2430         if (err)
2431                 return err;
2432
2433         err = kvm_arm_vmid_alloc_init();
2434         if (err) {
2435                 kvm_err("Failed to initialize VMID allocator.\n");
2436                 return err;
2437         }
2438
2439         if (!in_hyp_mode) {
2440                 err = init_hyp_mode();
2441                 if (err)
2442                         goto out_err;
2443         }
2444
2445         err = kvm_init_vector_slots();
2446         if (err) {
2447                 kvm_err("Cannot initialise vector slots\n");
2448                 goto out_hyp;
2449         }
2450
2451         err = init_subsystems();
2452         if (err)
2453                 goto out_hyp;
2454
2455         if (is_protected_kvm_enabled()) {
2456                 kvm_info("Protected nVHE mode initialized successfully\n");
2457         } else if (in_hyp_mode) {
2458                 kvm_info("VHE mode initialized successfully\n");
2459         } else {
2460                 kvm_info("Hyp mode initialized successfully\n");
2461         }
2462
2463         /*
2464          * FIXME: Do something reasonable if kvm_init() fails after pKVM
2465          * hypervisor protection is finalized.
2466          */
2467         err = kvm_init(sizeof(struct kvm_vcpu), 0, THIS_MODULE);
2468         if (err)
2469                 goto out_subs;
2470
2471         kvm_arm_initialised = true;
2472
2473         return 0;
2474
2475 out_subs:
2476         teardown_subsystems();
2477 out_hyp:
2478         if (!in_hyp_mode)
2479                 teardown_hyp_mode();
2480 out_err:
2481         kvm_arm_vmid_alloc_free();
2482         return err;
2483 }
2484
2485 static int __init early_kvm_mode_cfg(char *arg)
2486 {
2487         if (!arg)
2488                 return -EINVAL;
2489
2490         if (strcmp(arg, "none") == 0) {
2491                 kvm_mode = KVM_MODE_NONE;
2492                 return 0;
2493         }
2494
2495         if (!is_hyp_mode_available()) {
2496                 pr_warn_once("KVM is not available. Ignoring kvm-arm.mode\n");
2497                 return 0;
2498         }
2499
2500         if (strcmp(arg, "protected") == 0) {
2501                 if (!is_kernel_in_hyp_mode())
2502                         kvm_mode = KVM_MODE_PROTECTED;
2503                 else
2504                         pr_warn_once("Protected KVM not available with VHE\n");
2505
2506                 return 0;
2507         }
2508
2509         if (strcmp(arg, "nvhe") == 0 && !WARN_ON(is_kernel_in_hyp_mode())) {
2510                 kvm_mode = KVM_MODE_DEFAULT;
2511                 return 0;
2512         }
2513
2514         if (strcmp(arg, "nested") == 0 && !WARN_ON(!is_kernel_in_hyp_mode())) {
2515                 kvm_mode = KVM_MODE_NV;
2516                 return 0;
2517         }
2518
2519         return -EINVAL;
2520 }
2521 early_param("kvm-arm.mode", early_kvm_mode_cfg);
2522
2523 enum kvm_mode kvm_get_mode(void)
2524 {
2525         return kvm_mode;
2526 }
2527
2528 module_init(kvm_arm_init);