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/kmemleak.h> 20 #include <linux/kvm.h> 21 #include <linux/kvm_irqfd.h> 22 #include <linux/irqbypass.h> 23 #include <linux/sched/stat.h> 24 #include <linux/psci.h> 25 #include <trace/events/kvm.h> 26 27 #define CREATE_TRACE_POINTS 28 #include "trace_arm.h" 29 30 #include <linux/uaccess.h> 31 #include <asm/ptrace.h> 32 #include <asm/mman.h> 33 #include <asm/tlbflush.h> 34 #include <asm/cacheflush.h> 35 #include <asm/cpufeature.h> 36 #include <asm/virt.h> 37 #include <asm/kvm_arm.h> 38 #include <asm/kvm_asm.h> 39 #include <asm/kvm_mmu.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 DEFINE_STATIC_KEY_FALSE(kvm_protected_mode_initialized); 50 51 DECLARE_KVM_HYP_PER_CPU(unsigned long, kvm_hyp_vector); 52 53 DEFINE_PER_CPU(unsigned long, kvm_arm_hyp_stack_page); 54 DECLARE_KVM_NVHE_PER_CPU(struct kvm_nvhe_init_params, kvm_init_params); 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 71 if (cap->flags) 72 return -EINVAL; 73 74 switch (cap->cap) { 75 case KVM_CAP_ARM_NISV_TO_USER: 76 r = 0; 77 set_bit(KVM_ARCH_FLAG_RETURN_NISV_IO_ABORT_TO_USER, 78 &kvm->arch.flags); 79 break; 80 case KVM_CAP_ARM_MTE: 81 mutex_lock(&kvm->lock); 82 if (!system_supports_mte() || kvm->created_vcpus) { 83 r = -EINVAL; 84 } else { 85 r = 0; 86 set_bit(KVM_ARCH_FLAG_MTE_ENABLED, &kvm->arch.flags); 87 } 88 mutex_unlock(&kvm->lock); 89 break; 90 case KVM_CAP_ARM_SYSTEM_SUSPEND: 91 r = 0; 92 set_bit(KVM_ARCH_FLAG_SYSTEM_SUSPEND_ENABLED, &kvm->arch.flags); 93 break; 94 default: 95 r = -EINVAL; 96 break; 97 } 98 99 return r; 100 } 101 102 static int kvm_arm_default_max_vcpus(void) 103 { 104 return vgic_present ? kvm_vgic_get_max_vcpus() : KVM_MAX_VCPUS; 105 } 106 107 static void set_default_spectre(struct kvm *kvm) 108 { 109 /* 110 * The default is to expose CSV2 == 1 if the HW isn't affected. 111 * Although this is a per-CPU feature, we make it global because 112 * asymmetric systems are just a nuisance. 113 * 114 * Userspace can override this as long as it doesn't promise 115 * the impossible. 116 */ 117 if (arm64_get_spectre_v2_state() == SPECTRE_UNAFFECTED) 118 kvm->arch.pfr0_csv2 = 1; 119 if (arm64_get_meltdown_state() == SPECTRE_UNAFFECTED) 120 kvm->arch.pfr0_csv3 = 1; 121 } 122 123 /** 124 * kvm_arch_init_vm - initializes a VM data structure 125 * @kvm: pointer to the KVM struct 126 */ 127 int kvm_arch_init_vm(struct kvm *kvm, unsigned long type) 128 { 129 int ret; 130 131 ret = kvm_share_hyp(kvm, kvm + 1); 132 if (ret) 133 return ret; 134 135 ret = pkvm_init_host_vm(kvm); 136 if (ret) 137 goto err_unshare_kvm; 138 139 if (!zalloc_cpumask_var(&kvm->arch.supported_cpus, GFP_KERNEL_ACCOUNT)) { 140 ret = -ENOMEM; 141 goto err_unshare_kvm; 142 } 143 cpumask_copy(kvm->arch.supported_cpus, cpu_possible_mask); 144 145 ret = kvm_init_stage2_mmu(kvm, &kvm->arch.mmu, type); 146 if (ret) 147 goto err_free_cpumask; 148 149 kvm_vgic_early_init(kvm); 150 151 /* The maximum number of VCPUs is limited by the host's GIC model */ 152 kvm->max_vcpus = kvm_arm_default_max_vcpus(); 153 154 set_default_spectre(kvm); 155 kvm_arm_init_hypercalls(kvm); 156 157 /* 158 * Initialise the default PMUver before there is a chance to 159 * create an actual PMU. 160 */ 161 kvm->arch.dfr0_pmuver.imp = kvm_arm_pmu_get_pmuver_limit(); 162 163 return 0; 164 165 err_free_cpumask: 166 free_cpumask_var(kvm->arch.supported_cpus); 167 err_unshare_kvm: 168 kvm_unshare_hyp(kvm, kvm + 1); 169 return ret; 170 } 171 172 vm_fault_t kvm_arch_vcpu_fault(struct kvm_vcpu *vcpu, struct vm_fault *vmf) 173 { 174 return VM_FAULT_SIGBUS; 175 } 176 177 178 /** 179 * kvm_arch_destroy_vm - destroy the VM data structure 180 * @kvm: pointer to the KVM struct 181 */ 182 void kvm_arch_destroy_vm(struct kvm *kvm) 183 { 184 bitmap_free(kvm->arch.pmu_filter); 185 free_cpumask_var(kvm->arch.supported_cpus); 186 187 kvm_vgic_destroy(kvm); 188 189 if (is_protected_kvm_enabled()) 190 pkvm_destroy_hyp_vm(kvm); 191 192 kvm_destroy_vcpus(kvm); 193 194 kvm_unshare_hyp(kvm, kvm + 1); 195 } 196 197 int kvm_vm_ioctl_check_extension(struct kvm *kvm, long ext) 198 { 199 int r; 200 switch (ext) { 201 case KVM_CAP_IRQCHIP: 202 r = vgic_present; 203 break; 204 case KVM_CAP_IOEVENTFD: 205 case KVM_CAP_DEVICE_CTRL: 206 case KVM_CAP_USER_MEMORY: 207 case KVM_CAP_SYNC_MMU: 208 case KVM_CAP_DESTROY_MEMORY_REGION_WORKS: 209 case KVM_CAP_ONE_REG: 210 case KVM_CAP_ARM_PSCI: 211 case KVM_CAP_ARM_PSCI_0_2: 212 case KVM_CAP_READONLY_MEM: 213 case KVM_CAP_MP_STATE: 214 case KVM_CAP_IMMEDIATE_EXIT: 215 case KVM_CAP_VCPU_EVENTS: 216 case KVM_CAP_ARM_IRQ_LINE_LAYOUT_2: 217 case KVM_CAP_ARM_NISV_TO_USER: 218 case KVM_CAP_ARM_INJECT_EXT_DABT: 219 case KVM_CAP_SET_GUEST_DEBUG: 220 case KVM_CAP_VCPU_ATTRIBUTES: 221 case KVM_CAP_PTP_KVM: 222 case KVM_CAP_ARM_SYSTEM_SUSPEND: 223 case KVM_CAP_IRQFD_RESAMPLE: 224 r = 1; 225 break; 226 case KVM_CAP_SET_GUEST_DEBUG2: 227 return KVM_GUESTDBG_VALID_MASK; 228 case KVM_CAP_ARM_SET_DEVICE_ADDR: 229 r = 1; 230 break; 231 case KVM_CAP_NR_VCPUS: 232 /* 233 * ARM64 treats KVM_CAP_NR_CPUS differently from all other 234 * architectures, as it does not always bound it to 235 * KVM_CAP_MAX_VCPUS. It should not matter much because 236 * this is just an advisory value. 237 */ 238 r = min_t(unsigned int, num_online_cpus(), 239 kvm_arm_default_max_vcpus()); 240 break; 241 case KVM_CAP_MAX_VCPUS: 242 case KVM_CAP_MAX_VCPU_ID: 243 if (kvm) 244 r = kvm->max_vcpus; 245 else 246 r = kvm_arm_default_max_vcpus(); 247 break; 248 case KVM_CAP_MSI_DEVID: 249 if (!kvm) 250 r = -EINVAL; 251 else 252 r = kvm->arch.vgic.msis_require_devid; 253 break; 254 case KVM_CAP_ARM_USER_IRQ: 255 /* 256 * 1: EL1_VTIMER, EL1_PTIMER, and PMU. 257 * (bump this number if adding more devices) 258 */ 259 r = 1; 260 break; 261 case KVM_CAP_ARM_MTE: 262 r = system_supports_mte(); 263 break; 264 case KVM_CAP_STEAL_TIME: 265 r = kvm_arm_pvtime_supported(); 266 break; 267 case KVM_CAP_ARM_EL1_32BIT: 268 r = cpus_have_const_cap(ARM64_HAS_32BIT_EL1); 269 break; 270 case KVM_CAP_GUEST_DEBUG_HW_BPS: 271 r = get_num_brps(); 272 break; 273 case KVM_CAP_GUEST_DEBUG_HW_WPS: 274 r = get_num_wrps(); 275 break; 276 case KVM_CAP_ARM_PMU_V3: 277 r = kvm_arm_support_pmu_v3(); 278 break; 279 case KVM_CAP_ARM_INJECT_SERROR_ESR: 280 r = cpus_have_const_cap(ARM64_HAS_RAS_EXTN); 281 break; 282 case KVM_CAP_ARM_VM_IPA_SIZE: 283 r = get_kvm_ipa_limit(); 284 break; 285 case KVM_CAP_ARM_SVE: 286 r = system_supports_sve(); 287 break; 288 case KVM_CAP_ARM_PTRAUTH_ADDRESS: 289 case KVM_CAP_ARM_PTRAUTH_GENERIC: 290 r = system_has_full_ptr_auth(); 291 break; 292 default: 293 r = 0; 294 } 295 296 return r; 297 } 298 299 long kvm_arch_dev_ioctl(struct file *filp, 300 unsigned int ioctl, unsigned long arg) 301 { 302 return -EINVAL; 303 } 304 305 struct kvm *kvm_arch_alloc_vm(void) 306 { 307 size_t sz = sizeof(struct kvm); 308 309 if (!has_vhe()) 310 return kzalloc(sz, GFP_KERNEL_ACCOUNT); 311 312 return __vmalloc(sz, GFP_KERNEL_ACCOUNT | __GFP_HIGHMEM | __GFP_ZERO); 313 } 314 315 int kvm_arch_vcpu_precreate(struct kvm *kvm, unsigned int id) 316 { 317 if (irqchip_in_kernel(kvm) && vgic_initialized(kvm)) 318 return -EBUSY; 319 320 if (id >= kvm->max_vcpus) 321 return -EINVAL; 322 323 return 0; 324 } 325 326 int kvm_arch_vcpu_create(struct kvm_vcpu *vcpu) 327 { 328 int err; 329 330 /* Force users to call KVM_ARM_VCPU_INIT */ 331 vcpu->arch.target = -1; 332 bitmap_zero(vcpu->arch.features, KVM_VCPU_MAX_FEATURES); 333 334 vcpu->arch.mmu_page_cache.gfp_zero = __GFP_ZERO; 335 336 /* 337 * Default value for the FP state, will be overloaded at load 338 * time if we support FP (pretty likely) 339 */ 340 vcpu->arch.fp_state = FP_STATE_FREE; 341 342 /* Set up the timer */ 343 kvm_timer_vcpu_init(vcpu); 344 345 kvm_pmu_vcpu_init(vcpu); 346 347 kvm_arm_reset_debug_ptr(vcpu); 348 349 kvm_arm_pvtime_vcpu_init(&vcpu->arch); 350 351 vcpu->arch.hw_mmu = &vcpu->kvm->arch.mmu; 352 353 err = kvm_vgic_vcpu_init(vcpu); 354 if (err) 355 return err; 356 357 return kvm_share_hyp(vcpu, vcpu + 1); 358 } 359 360 void kvm_arch_vcpu_postcreate(struct kvm_vcpu *vcpu) 361 { 362 } 363 364 void kvm_arch_vcpu_destroy(struct kvm_vcpu *vcpu) 365 { 366 if (vcpu_has_run_once(vcpu) && unlikely(!irqchip_in_kernel(vcpu->kvm))) 367 static_branch_dec(&userspace_irqchip_in_use); 368 369 kvm_mmu_free_memory_cache(&vcpu->arch.mmu_page_cache); 370 kvm_timer_vcpu_terminate(vcpu); 371 kvm_pmu_vcpu_destroy(vcpu); 372 373 kvm_arm_vcpu_destroy(vcpu); 374 } 375 376 void kvm_arch_vcpu_blocking(struct kvm_vcpu *vcpu) 377 { 378 379 } 380 381 void kvm_arch_vcpu_unblocking(struct kvm_vcpu *vcpu) 382 { 383 384 } 385 386 void kvm_arch_vcpu_load(struct kvm_vcpu *vcpu, int cpu) 387 { 388 struct kvm_s2_mmu *mmu; 389 int *last_ran; 390 391 mmu = vcpu->arch.hw_mmu; 392 last_ran = this_cpu_ptr(mmu->last_vcpu_ran); 393 394 /* 395 * We guarantee that both TLBs and I-cache are private to each 396 * vcpu. If detecting that a vcpu from the same VM has 397 * previously run on the same physical CPU, call into the 398 * hypervisor code to nuke the relevant contexts. 399 * 400 * We might get preempted before the vCPU actually runs, but 401 * over-invalidation doesn't affect correctness. 402 */ 403 if (*last_ran != vcpu->vcpu_id) { 404 kvm_call_hyp(__kvm_flush_cpu_context, mmu); 405 *last_ran = vcpu->vcpu_id; 406 } 407 408 vcpu->cpu = cpu; 409 410 kvm_vgic_load(vcpu); 411 kvm_timer_vcpu_load(vcpu); 412 if (has_vhe()) 413 kvm_vcpu_load_sysregs_vhe(vcpu); 414 kvm_arch_vcpu_load_fp(vcpu); 415 kvm_vcpu_pmu_restore_guest(vcpu); 416 if (kvm_arm_is_pvtime_enabled(&vcpu->arch)) 417 kvm_make_request(KVM_REQ_RECORD_STEAL, vcpu); 418 419 if (single_task_running()) 420 vcpu_clear_wfx_traps(vcpu); 421 else 422 vcpu_set_wfx_traps(vcpu); 423 424 if (vcpu_has_ptrauth(vcpu)) 425 vcpu_ptrauth_disable(vcpu); 426 kvm_arch_vcpu_load_debug_state_flags(vcpu); 427 428 if (!cpumask_test_cpu(smp_processor_id(), vcpu->kvm->arch.supported_cpus)) 429 vcpu_set_on_unsupported_cpu(vcpu); 430 } 431 432 void kvm_arch_vcpu_put(struct kvm_vcpu *vcpu) 433 { 434 kvm_arch_vcpu_put_debug_state_flags(vcpu); 435 kvm_arch_vcpu_put_fp(vcpu); 436 if (has_vhe()) 437 kvm_vcpu_put_sysregs_vhe(vcpu); 438 kvm_timer_vcpu_put(vcpu); 439 kvm_vgic_put(vcpu); 440 kvm_vcpu_pmu_restore_host(vcpu); 441 kvm_arm_vmid_clear_active(); 442 443 vcpu_clear_on_unsupported_cpu(vcpu); 444 vcpu->cpu = -1; 445 } 446 447 void kvm_arm_vcpu_power_off(struct kvm_vcpu *vcpu) 448 { 449 vcpu->arch.mp_state.mp_state = KVM_MP_STATE_STOPPED; 450 kvm_make_request(KVM_REQ_SLEEP, vcpu); 451 kvm_vcpu_kick(vcpu); 452 } 453 454 bool kvm_arm_vcpu_stopped(struct kvm_vcpu *vcpu) 455 { 456 return vcpu->arch.mp_state.mp_state == KVM_MP_STATE_STOPPED; 457 } 458 459 static void kvm_arm_vcpu_suspend(struct kvm_vcpu *vcpu) 460 { 461 vcpu->arch.mp_state.mp_state = KVM_MP_STATE_SUSPENDED; 462 kvm_make_request(KVM_REQ_SUSPEND, vcpu); 463 kvm_vcpu_kick(vcpu); 464 } 465 466 static bool kvm_arm_vcpu_suspended(struct kvm_vcpu *vcpu) 467 { 468 return vcpu->arch.mp_state.mp_state == KVM_MP_STATE_SUSPENDED; 469 } 470 471 int kvm_arch_vcpu_ioctl_get_mpstate(struct kvm_vcpu *vcpu, 472 struct kvm_mp_state *mp_state) 473 { 474 *mp_state = vcpu->arch.mp_state; 475 476 return 0; 477 } 478 479 int kvm_arch_vcpu_ioctl_set_mpstate(struct kvm_vcpu *vcpu, 480 struct kvm_mp_state *mp_state) 481 { 482 int ret = 0; 483 484 switch (mp_state->mp_state) { 485 case KVM_MP_STATE_RUNNABLE: 486 vcpu->arch.mp_state = *mp_state; 487 break; 488 case KVM_MP_STATE_STOPPED: 489 kvm_arm_vcpu_power_off(vcpu); 490 break; 491 case KVM_MP_STATE_SUSPENDED: 492 kvm_arm_vcpu_suspend(vcpu); 493 break; 494 default: 495 ret = -EINVAL; 496 } 497 498 return ret; 499 } 500 501 /** 502 * kvm_arch_vcpu_runnable - determine if the vcpu can be scheduled 503 * @v: The VCPU pointer 504 * 505 * If the guest CPU is not waiting for interrupts or an interrupt line is 506 * asserted, the CPU is by definition runnable. 507 */ 508 int kvm_arch_vcpu_runnable(struct kvm_vcpu *v) 509 { 510 bool irq_lines = *vcpu_hcr(v) & (HCR_VI | HCR_VF); 511 return ((irq_lines || kvm_vgic_vcpu_pending_irq(v)) 512 && !kvm_arm_vcpu_stopped(v) && !v->arch.pause); 513 } 514 515 bool kvm_arch_vcpu_in_kernel(struct kvm_vcpu *vcpu) 516 { 517 return vcpu_mode_priv(vcpu); 518 } 519 520 #ifdef CONFIG_GUEST_PERF_EVENTS 521 unsigned long kvm_arch_vcpu_get_ip(struct kvm_vcpu *vcpu) 522 { 523 return *vcpu_pc(vcpu); 524 } 525 #endif 526 527 static int kvm_vcpu_initialized(struct kvm_vcpu *vcpu) 528 { 529 return vcpu->arch.target >= 0; 530 } 531 532 /* 533 * Handle both the initialisation that is being done when the vcpu is 534 * run for the first time, as well as the updates that must be 535 * performed each time we get a new thread dealing with this vcpu. 536 */ 537 int kvm_arch_vcpu_run_pid_change(struct kvm_vcpu *vcpu) 538 { 539 struct kvm *kvm = vcpu->kvm; 540 int ret; 541 542 if (!kvm_vcpu_initialized(vcpu)) 543 return -ENOEXEC; 544 545 if (!kvm_arm_vcpu_is_finalized(vcpu)) 546 return -EPERM; 547 548 ret = kvm_arch_vcpu_run_map_fp(vcpu); 549 if (ret) 550 return ret; 551 552 if (likely(vcpu_has_run_once(vcpu))) 553 return 0; 554 555 kvm_arm_vcpu_init_debug(vcpu); 556 557 if (likely(irqchip_in_kernel(kvm))) { 558 /* 559 * Map the VGIC hardware resources before running a vcpu the 560 * first time on this VM. 561 */ 562 ret = kvm_vgic_map_resources(kvm); 563 if (ret) 564 return ret; 565 } 566 567 ret = kvm_timer_enable(vcpu); 568 if (ret) 569 return ret; 570 571 ret = kvm_arm_pmu_v3_enable(vcpu); 572 if (ret) 573 return ret; 574 575 if (is_protected_kvm_enabled()) { 576 ret = pkvm_create_hyp_vm(kvm); 577 if (ret) 578 return ret; 579 } 580 581 if (!irqchip_in_kernel(kvm)) { 582 /* 583 * Tell the rest of the code that there are userspace irqchip 584 * VMs in the wild. 585 */ 586 static_branch_inc(&userspace_irqchip_in_use); 587 } 588 589 /* 590 * Initialize traps for protected VMs. 591 * NOTE: Move to run in EL2 directly, rather than via a hypercall, once 592 * the code is in place for first run initialization at EL2. 593 */ 594 if (kvm_vm_is_protected(kvm)) 595 kvm_call_hyp_nvhe(__pkvm_vcpu_init_traps, vcpu); 596 597 mutex_lock(&kvm->lock); 598 set_bit(KVM_ARCH_FLAG_HAS_RAN_ONCE, &kvm->arch.flags); 599 mutex_unlock(&kvm->lock); 600 601 return ret; 602 } 603 604 bool kvm_arch_intc_initialized(struct kvm *kvm) 605 { 606 return vgic_initialized(kvm); 607 } 608 609 void kvm_arm_halt_guest(struct kvm *kvm) 610 { 611 unsigned long i; 612 struct kvm_vcpu *vcpu; 613 614 kvm_for_each_vcpu(i, vcpu, kvm) 615 vcpu->arch.pause = true; 616 kvm_make_all_cpus_request(kvm, KVM_REQ_SLEEP); 617 } 618 619 void kvm_arm_resume_guest(struct kvm *kvm) 620 { 621 unsigned long i; 622 struct kvm_vcpu *vcpu; 623 624 kvm_for_each_vcpu(i, vcpu, kvm) { 625 vcpu->arch.pause = false; 626 __kvm_vcpu_wake_up(vcpu); 627 } 628 } 629 630 static void kvm_vcpu_sleep(struct kvm_vcpu *vcpu) 631 { 632 struct rcuwait *wait = kvm_arch_vcpu_get_wait(vcpu); 633 634 rcuwait_wait_event(wait, 635 (!kvm_arm_vcpu_stopped(vcpu)) && (!vcpu->arch.pause), 636 TASK_INTERRUPTIBLE); 637 638 if (kvm_arm_vcpu_stopped(vcpu) || vcpu->arch.pause) { 639 /* Awaken to handle a signal, request we sleep again later. */ 640 kvm_make_request(KVM_REQ_SLEEP, vcpu); 641 } 642 643 /* 644 * Make sure we will observe a potential reset request if we've 645 * observed a change to the power state. Pairs with the smp_wmb() in 646 * kvm_psci_vcpu_on(). 647 */ 648 smp_rmb(); 649 } 650 651 /** 652 * kvm_vcpu_wfi - emulate Wait-For-Interrupt behavior 653 * @vcpu: The VCPU pointer 654 * 655 * Suspend execution of a vCPU until a valid wake event is detected, i.e. until 656 * the vCPU is runnable. The vCPU may or may not be scheduled out, depending 657 * on when a wake event arrives, e.g. there may already be a pending wake event. 658 */ 659 void kvm_vcpu_wfi(struct kvm_vcpu *vcpu) 660 { 661 /* 662 * Sync back the state of the GIC CPU interface so that we have 663 * the latest PMR and group enables. This ensures that 664 * kvm_arch_vcpu_runnable has up-to-date data to decide whether 665 * we have pending interrupts, e.g. when determining if the 666 * vCPU should block. 667 * 668 * For the same reason, we want to tell GICv4 that we need 669 * doorbells to be signalled, should an interrupt become pending. 670 */ 671 preempt_disable(); 672 kvm_vgic_vmcr_sync(vcpu); 673 vgic_v4_put(vcpu, true); 674 preempt_enable(); 675 676 kvm_vcpu_halt(vcpu); 677 vcpu_clear_flag(vcpu, IN_WFIT); 678 679 preempt_disable(); 680 vgic_v4_load(vcpu); 681 preempt_enable(); 682 } 683 684 static int kvm_vcpu_suspend(struct kvm_vcpu *vcpu) 685 { 686 if (!kvm_arm_vcpu_suspended(vcpu)) 687 return 1; 688 689 kvm_vcpu_wfi(vcpu); 690 691 /* 692 * The suspend state is sticky; we do not leave it until userspace 693 * explicitly marks the vCPU as runnable. Request that we suspend again 694 * later. 695 */ 696 kvm_make_request(KVM_REQ_SUSPEND, vcpu); 697 698 /* 699 * Check to make sure the vCPU is actually runnable. If so, exit to 700 * userspace informing it of the wakeup condition. 701 */ 702 if (kvm_arch_vcpu_runnable(vcpu)) { 703 memset(&vcpu->run->system_event, 0, sizeof(vcpu->run->system_event)); 704 vcpu->run->system_event.type = KVM_SYSTEM_EVENT_WAKEUP; 705 vcpu->run->exit_reason = KVM_EXIT_SYSTEM_EVENT; 706 return 0; 707 } 708 709 /* 710 * Otherwise, we were unblocked to process a different event, such as a 711 * pending signal. Return 1 and allow kvm_arch_vcpu_ioctl_run() to 712 * process the event. 713 */ 714 return 1; 715 } 716 717 /** 718 * check_vcpu_requests - check and handle pending vCPU requests 719 * @vcpu: the VCPU pointer 720 * 721 * Return: 1 if we should enter the guest 722 * 0 if we should exit to userspace 723 * < 0 if we should exit to userspace, where the return value indicates 724 * an error 725 */ 726 static int check_vcpu_requests(struct kvm_vcpu *vcpu) 727 { 728 if (kvm_request_pending(vcpu)) { 729 if (kvm_check_request(KVM_REQ_SLEEP, vcpu)) 730 kvm_vcpu_sleep(vcpu); 731 732 if (kvm_check_request(KVM_REQ_VCPU_RESET, vcpu)) 733 kvm_reset_vcpu(vcpu); 734 735 /* 736 * Clear IRQ_PENDING requests that were made to guarantee 737 * that a VCPU sees new virtual interrupts. 738 */ 739 kvm_check_request(KVM_REQ_IRQ_PENDING, vcpu); 740 741 if (kvm_check_request(KVM_REQ_RECORD_STEAL, vcpu)) 742 kvm_update_stolen_time(vcpu); 743 744 if (kvm_check_request(KVM_REQ_RELOAD_GICv4, vcpu)) { 745 /* The distributor enable bits were changed */ 746 preempt_disable(); 747 vgic_v4_put(vcpu, false); 748 vgic_v4_load(vcpu); 749 preempt_enable(); 750 } 751 752 if (kvm_check_request(KVM_REQ_RELOAD_PMU, vcpu)) 753 kvm_pmu_handle_pmcr(vcpu, 754 __vcpu_sys_reg(vcpu, PMCR_EL0)); 755 756 if (kvm_check_request(KVM_REQ_SUSPEND, vcpu)) 757 return kvm_vcpu_suspend(vcpu); 758 759 if (kvm_dirty_ring_check_request(vcpu)) 760 return 0; 761 } 762 763 return 1; 764 } 765 766 static bool vcpu_mode_is_bad_32bit(struct kvm_vcpu *vcpu) 767 { 768 if (likely(!vcpu_mode_is_32bit(vcpu))) 769 return false; 770 771 return !kvm_supports_32bit_el0(); 772 } 773 774 /** 775 * kvm_vcpu_exit_request - returns true if the VCPU should *not* enter the guest 776 * @vcpu: The VCPU pointer 777 * @ret: Pointer to write optional return code 778 * 779 * Returns: true if the VCPU needs to return to a preemptible + interruptible 780 * and skip guest entry. 781 * 782 * This function disambiguates between two different types of exits: exits to a 783 * preemptible + interruptible kernel context and exits to userspace. For an 784 * exit to userspace, this function will write the return code to ret and return 785 * true. For an exit to preemptible + interruptible kernel context (i.e. check 786 * for pending work and re-enter), return true without writing to ret. 787 */ 788 static bool kvm_vcpu_exit_request(struct kvm_vcpu *vcpu, int *ret) 789 { 790 struct kvm_run *run = vcpu->run; 791 792 /* 793 * If we're using a userspace irqchip, then check if we need 794 * to tell a userspace irqchip about timer or PMU level 795 * changes and if so, exit to userspace (the actual level 796 * state gets updated in kvm_timer_update_run and 797 * kvm_pmu_update_run below). 798 */ 799 if (static_branch_unlikely(&userspace_irqchip_in_use)) { 800 if (kvm_timer_should_notify_user(vcpu) || 801 kvm_pmu_should_notify_user(vcpu)) { 802 *ret = -EINTR; 803 run->exit_reason = KVM_EXIT_INTR; 804 return true; 805 } 806 } 807 808 if (unlikely(vcpu_on_unsupported_cpu(vcpu))) { 809 run->exit_reason = KVM_EXIT_FAIL_ENTRY; 810 run->fail_entry.hardware_entry_failure_reason = KVM_EXIT_FAIL_ENTRY_CPU_UNSUPPORTED; 811 run->fail_entry.cpu = smp_processor_id(); 812 *ret = 0; 813 return true; 814 } 815 816 return kvm_request_pending(vcpu) || 817 xfer_to_guest_mode_work_pending(); 818 } 819 820 /* 821 * Actually run the vCPU, entering an RCU extended quiescent state (EQS) while 822 * the vCPU is running. 823 * 824 * This must be noinstr as instrumentation may make use of RCU, and this is not 825 * safe during the EQS. 826 */ 827 static int noinstr kvm_arm_vcpu_enter_exit(struct kvm_vcpu *vcpu) 828 { 829 int ret; 830 831 guest_state_enter_irqoff(); 832 ret = kvm_call_hyp_ret(__kvm_vcpu_run, vcpu); 833 guest_state_exit_irqoff(); 834 835 return ret; 836 } 837 838 /** 839 * kvm_arch_vcpu_ioctl_run - the main VCPU run function to execute guest code 840 * @vcpu: The VCPU pointer 841 * 842 * This function is called through the VCPU_RUN ioctl called from user space. It 843 * will execute VM code in a loop until the time slice for the process is used 844 * or some emulation is needed from user space in which case the function will 845 * return with return value 0 and with the kvm_run structure filled in with the 846 * required data for the requested emulation. 847 */ 848 int kvm_arch_vcpu_ioctl_run(struct kvm_vcpu *vcpu) 849 { 850 struct kvm_run *run = vcpu->run; 851 int ret; 852 853 if (run->exit_reason == KVM_EXIT_MMIO) { 854 ret = kvm_handle_mmio_return(vcpu); 855 if (ret) 856 return ret; 857 } 858 859 vcpu_load(vcpu); 860 861 if (run->immediate_exit) { 862 ret = -EINTR; 863 goto out; 864 } 865 866 kvm_sigset_activate(vcpu); 867 868 ret = 1; 869 run->exit_reason = KVM_EXIT_UNKNOWN; 870 run->flags = 0; 871 while (ret > 0) { 872 /* 873 * Check conditions before entering the guest 874 */ 875 ret = xfer_to_guest_mode_handle_work(vcpu); 876 if (!ret) 877 ret = 1; 878 879 if (ret > 0) 880 ret = check_vcpu_requests(vcpu); 881 882 /* 883 * Preparing the interrupts to be injected also 884 * involves poking the GIC, which must be done in a 885 * non-preemptible context. 886 */ 887 preempt_disable(); 888 889 /* 890 * The VMID allocator only tracks active VMIDs per 891 * physical CPU, and therefore the VMID allocated may not be 892 * preserved on VMID roll-over if the task was preempted, 893 * making a thread's VMID inactive. So we need to call 894 * kvm_arm_vmid_update() in non-premptible context. 895 */ 896 kvm_arm_vmid_update(&vcpu->arch.hw_mmu->vmid); 897 898 kvm_pmu_flush_hwstate(vcpu); 899 900 local_irq_disable(); 901 902 kvm_vgic_flush_hwstate(vcpu); 903 904 kvm_pmu_update_vcpu_events(vcpu); 905 906 /* 907 * Ensure we set mode to IN_GUEST_MODE after we disable 908 * interrupts and before the final VCPU requests check. 909 * See the comment in kvm_vcpu_exiting_guest_mode() and 910 * Documentation/virt/kvm/vcpu-requests.rst 911 */ 912 smp_store_mb(vcpu->mode, IN_GUEST_MODE); 913 914 if (ret <= 0 || kvm_vcpu_exit_request(vcpu, &ret)) { 915 vcpu->mode = OUTSIDE_GUEST_MODE; 916 isb(); /* Ensure work in x_flush_hwstate is committed */ 917 kvm_pmu_sync_hwstate(vcpu); 918 if (static_branch_unlikely(&userspace_irqchip_in_use)) 919 kvm_timer_sync_user(vcpu); 920 kvm_vgic_sync_hwstate(vcpu); 921 local_irq_enable(); 922 preempt_enable(); 923 continue; 924 } 925 926 kvm_arm_setup_debug(vcpu); 927 kvm_arch_vcpu_ctxflush_fp(vcpu); 928 929 /************************************************************** 930 * Enter the guest 931 */ 932 trace_kvm_entry(*vcpu_pc(vcpu)); 933 guest_timing_enter_irqoff(); 934 935 ret = kvm_arm_vcpu_enter_exit(vcpu); 936 937 vcpu->mode = OUTSIDE_GUEST_MODE; 938 vcpu->stat.exits++; 939 /* 940 * Back from guest 941 *************************************************************/ 942 943 kvm_arm_clear_debug(vcpu); 944 945 /* 946 * We must sync the PMU state before the vgic state so 947 * that the vgic can properly sample the updated state of the 948 * interrupt line. 949 */ 950 kvm_pmu_sync_hwstate(vcpu); 951 952 /* 953 * Sync the vgic state before syncing the timer state because 954 * the timer code needs to know if the virtual timer 955 * interrupts are active. 956 */ 957 kvm_vgic_sync_hwstate(vcpu); 958 959 /* 960 * Sync the timer hardware state before enabling interrupts as 961 * we don't want vtimer interrupts to race with syncing the 962 * timer virtual interrupt state. 963 */ 964 if (static_branch_unlikely(&userspace_irqchip_in_use)) 965 kvm_timer_sync_user(vcpu); 966 967 kvm_arch_vcpu_ctxsync_fp(vcpu); 968 969 /* 970 * We must ensure that any pending interrupts are taken before 971 * we exit guest timing so that timer ticks are accounted as 972 * guest time. Transiently unmask interrupts so that any 973 * pending interrupts are taken. 974 * 975 * Per ARM DDI 0487G.b section D1.13.4, an ISB (or other 976 * context synchronization event) is necessary to ensure that 977 * pending interrupts are taken. 978 */ 979 if (ARM_EXCEPTION_CODE(ret) == ARM_EXCEPTION_IRQ) { 980 local_irq_enable(); 981 isb(); 982 local_irq_disable(); 983 } 984 985 guest_timing_exit_irqoff(); 986 987 local_irq_enable(); 988 989 trace_kvm_exit(ret, kvm_vcpu_trap_get_class(vcpu), *vcpu_pc(vcpu)); 990 991 /* Exit types that need handling before we can be preempted */ 992 handle_exit_early(vcpu, ret); 993 994 preempt_enable(); 995 996 /* 997 * The ARMv8 architecture doesn't give the hypervisor 998 * a mechanism to prevent a guest from dropping to AArch32 EL0 999 * if implemented by the CPU. If we spot the guest in such 1000 * state and that we decided it wasn't supposed to do so (like 1001 * with the asymmetric AArch32 case), return to userspace with 1002 * a fatal error. 1003 */ 1004 if (vcpu_mode_is_bad_32bit(vcpu)) { 1005 /* 1006 * As we have caught the guest red-handed, decide that 1007 * it isn't fit for purpose anymore by making the vcpu 1008 * invalid. The VMM can try and fix it by issuing a 1009 * KVM_ARM_VCPU_INIT if it really wants to. 1010 */ 1011 vcpu->arch.target = -1; 1012 ret = ARM_EXCEPTION_IL; 1013 } 1014 1015 ret = handle_exit(vcpu, ret); 1016 } 1017 1018 /* Tell userspace about in-kernel device output levels */ 1019 if (unlikely(!irqchip_in_kernel(vcpu->kvm))) { 1020 kvm_timer_update_run(vcpu); 1021 kvm_pmu_update_run(vcpu); 1022 } 1023 1024 kvm_sigset_deactivate(vcpu); 1025 1026 out: 1027 /* 1028 * In the unlikely event that we are returning to userspace 1029 * with pending exceptions or PC adjustment, commit these 1030 * adjustments in order to give userspace a consistent view of 1031 * the vcpu state. Note that this relies on __kvm_adjust_pc() 1032 * being preempt-safe on VHE. 1033 */ 1034 if (unlikely(vcpu_get_flag(vcpu, PENDING_EXCEPTION) || 1035 vcpu_get_flag(vcpu, INCREMENT_PC))) 1036 kvm_call_hyp(__kvm_adjust_pc, vcpu); 1037 1038 vcpu_put(vcpu); 1039 return ret; 1040 } 1041 1042 static int vcpu_interrupt_line(struct kvm_vcpu *vcpu, int number, bool level) 1043 { 1044 int bit_index; 1045 bool set; 1046 unsigned long *hcr; 1047 1048 if (number == KVM_ARM_IRQ_CPU_IRQ) 1049 bit_index = __ffs(HCR_VI); 1050 else /* KVM_ARM_IRQ_CPU_FIQ */ 1051 bit_index = __ffs(HCR_VF); 1052 1053 hcr = vcpu_hcr(vcpu); 1054 if (level) 1055 set = test_and_set_bit(bit_index, hcr); 1056 else 1057 set = test_and_clear_bit(bit_index, hcr); 1058 1059 /* 1060 * If we didn't change anything, no need to wake up or kick other CPUs 1061 */ 1062 if (set == level) 1063 return 0; 1064 1065 /* 1066 * The vcpu irq_lines field was updated, wake up sleeping VCPUs and 1067 * trigger a world-switch round on the running physical CPU to set the 1068 * virtual IRQ/FIQ fields in the HCR appropriately. 1069 */ 1070 kvm_make_request(KVM_REQ_IRQ_PENDING, vcpu); 1071 kvm_vcpu_kick(vcpu); 1072 1073 return 0; 1074 } 1075 1076 int kvm_vm_ioctl_irq_line(struct kvm *kvm, struct kvm_irq_level *irq_level, 1077 bool line_status) 1078 { 1079 u32 irq = irq_level->irq; 1080 unsigned int irq_type, vcpu_idx, irq_num; 1081 int nrcpus = atomic_read(&kvm->online_vcpus); 1082 struct kvm_vcpu *vcpu = NULL; 1083 bool level = irq_level->level; 1084 1085 irq_type = (irq >> KVM_ARM_IRQ_TYPE_SHIFT) & KVM_ARM_IRQ_TYPE_MASK; 1086 vcpu_idx = (irq >> KVM_ARM_IRQ_VCPU_SHIFT) & KVM_ARM_IRQ_VCPU_MASK; 1087 vcpu_idx += ((irq >> KVM_ARM_IRQ_VCPU2_SHIFT) & KVM_ARM_IRQ_VCPU2_MASK) * (KVM_ARM_IRQ_VCPU_MASK + 1); 1088 irq_num = (irq >> KVM_ARM_IRQ_NUM_SHIFT) & KVM_ARM_IRQ_NUM_MASK; 1089 1090 trace_kvm_irq_line(irq_type, vcpu_idx, irq_num, irq_level->level); 1091 1092 switch (irq_type) { 1093 case KVM_ARM_IRQ_TYPE_CPU: 1094 if (irqchip_in_kernel(kvm)) 1095 return -ENXIO; 1096 1097 if (vcpu_idx >= nrcpus) 1098 return -EINVAL; 1099 1100 vcpu = kvm_get_vcpu(kvm, vcpu_idx); 1101 if (!vcpu) 1102 return -EINVAL; 1103 1104 if (irq_num > KVM_ARM_IRQ_CPU_FIQ) 1105 return -EINVAL; 1106 1107 return vcpu_interrupt_line(vcpu, irq_num, level); 1108 case KVM_ARM_IRQ_TYPE_PPI: 1109 if (!irqchip_in_kernel(kvm)) 1110 return -ENXIO; 1111 1112 if (vcpu_idx >= nrcpus) 1113 return -EINVAL; 1114 1115 vcpu = kvm_get_vcpu(kvm, vcpu_idx); 1116 if (!vcpu) 1117 return -EINVAL; 1118 1119 if (irq_num < VGIC_NR_SGIS || irq_num >= VGIC_NR_PRIVATE_IRQS) 1120 return -EINVAL; 1121 1122 return kvm_vgic_inject_irq(kvm, vcpu->vcpu_id, irq_num, level, NULL); 1123 case KVM_ARM_IRQ_TYPE_SPI: 1124 if (!irqchip_in_kernel(kvm)) 1125 return -ENXIO; 1126 1127 if (irq_num < VGIC_NR_PRIVATE_IRQS) 1128 return -EINVAL; 1129 1130 return kvm_vgic_inject_irq(kvm, 0, irq_num, level, NULL); 1131 } 1132 1133 return -EINVAL; 1134 } 1135 1136 static int kvm_vcpu_set_target(struct kvm_vcpu *vcpu, 1137 const struct kvm_vcpu_init *init) 1138 { 1139 unsigned int i, ret; 1140 u32 phys_target = kvm_target_cpu(); 1141 1142 if (init->target != phys_target) 1143 return -EINVAL; 1144 1145 /* 1146 * Secondary and subsequent calls to KVM_ARM_VCPU_INIT must 1147 * use the same target. 1148 */ 1149 if (vcpu->arch.target != -1 && vcpu->arch.target != init->target) 1150 return -EINVAL; 1151 1152 /* -ENOENT for unknown features, -EINVAL for invalid combinations. */ 1153 for (i = 0; i < sizeof(init->features) * 8; i++) { 1154 bool set = (init->features[i / 32] & (1 << (i % 32))); 1155 1156 if (set && i >= KVM_VCPU_MAX_FEATURES) 1157 return -ENOENT; 1158 1159 /* 1160 * Secondary and subsequent calls to KVM_ARM_VCPU_INIT must 1161 * use the same feature set. 1162 */ 1163 if (vcpu->arch.target != -1 && i < KVM_VCPU_MAX_FEATURES && 1164 test_bit(i, vcpu->arch.features) != set) 1165 return -EINVAL; 1166 1167 if (set) 1168 set_bit(i, vcpu->arch.features); 1169 } 1170 1171 vcpu->arch.target = phys_target; 1172 1173 /* Now we know what it is, we can reset it. */ 1174 ret = kvm_reset_vcpu(vcpu); 1175 if (ret) { 1176 vcpu->arch.target = -1; 1177 bitmap_zero(vcpu->arch.features, KVM_VCPU_MAX_FEATURES); 1178 } 1179 1180 return ret; 1181 } 1182 1183 static int kvm_arch_vcpu_ioctl_vcpu_init(struct kvm_vcpu *vcpu, 1184 struct kvm_vcpu_init *init) 1185 { 1186 int ret; 1187 1188 ret = kvm_vcpu_set_target(vcpu, init); 1189 if (ret) 1190 return ret; 1191 1192 /* 1193 * Ensure a rebooted VM will fault in RAM pages and detect if the 1194 * guest MMU is turned off and flush the caches as needed. 1195 * 1196 * S2FWB enforces all memory accesses to RAM being cacheable, 1197 * ensuring that the data side is always coherent. We still 1198 * need to invalidate the I-cache though, as FWB does *not* 1199 * imply CTR_EL0.DIC. 1200 */ 1201 if (vcpu_has_run_once(vcpu)) { 1202 if (!cpus_have_final_cap(ARM64_HAS_STAGE2_FWB)) 1203 stage2_unmap_vm(vcpu->kvm); 1204 else 1205 icache_inval_all_pou(); 1206 } 1207 1208 vcpu_reset_hcr(vcpu); 1209 vcpu->arch.cptr_el2 = CPTR_EL2_DEFAULT; 1210 1211 /* 1212 * Handle the "start in power-off" case. 1213 */ 1214 if (test_bit(KVM_ARM_VCPU_POWER_OFF, vcpu->arch.features)) 1215 kvm_arm_vcpu_power_off(vcpu); 1216 else 1217 vcpu->arch.mp_state.mp_state = KVM_MP_STATE_RUNNABLE; 1218 1219 return 0; 1220 } 1221 1222 static int kvm_arm_vcpu_set_attr(struct kvm_vcpu *vcpu, 1223 struct kvm_device_attr *attr) 1224 { 1225 int ret = -ENXIO; 1226 1227 switch (attr->group) { 1228 default: 1229 ret = kvm_arm_vcpu_arch_set_attr(vcpu, attr); 1230 break; 1231 } 1232 1233 return ret; 1234 } 1235 1236 static int kvm_arm_vcpu_get_attr(struct kvm_vcpu *vcpu, 1237 struct kvm_device_attr *attr) 1238 { 1239 int ret = -ENXIO; 1240 1241 switch (attr->group) { 1242 default: 1243 ret = kvm_arm_vcpu_arch_get_attr(vcpu, attr); 1244 break; 1245 } 1246 1247 return ret; 1248 } 1249 1250 static int kvm_arm_vcpu_has_attr(struct kvm_vcpu *vcpu, 1251 struct kvm_device_attr *attr) 1252 { 1253 int ret = -ENXIO; 1254 1255 switch (attr->group) { 1256 default: 1257 ret = kvm_arm_vcpu_arch_has_attr(vcpu, attr); 1258 break; 1259 } 1260 1261 return ret; 1262 } 1263 1264 static int kvm_arm_vcpu_get_events(struct kvm_vcpu *vcpu, 1265 struct kvm_vcpu_events *events) 1266 { 1267 memset(events, 0, sizeof(*events)); 1268 1269 return __kvm_arm_vcpu_get_events(vcpu, events); 1270 } 1271 1272 static int kvm_arm_vcpu_set_events(struct kvm_vcpu *vcpu, 1273 struct kvm_vcpu_events *events) 1274 { 1275 int i; 1276 1277 /* check whether the reserved field is zero */ 1278 for (i = 0; i < ARRAY_SIZE(events->reserved); i++) 1279 if (events->reserved[i]) 1280 return -EINVAL; 1281 1282 /* check whether the pad field is zero */ 1283 for (i = 0; i < ARRAY_SIZE(events->exception.pad); i++) 1284 if (events->exception.pad[i]) 1285 return -EINVAL; 1286 1287 return __kvm_arm_vcpu_set_events(vcpu, events); 1288 } 1289 1290 long kvm_arch_vcpu_ioctl(struct file *filp, 1291 unsigned int ioctl, unsigned long arg) 1292 { 1293 struct kvm_vcpu *vcpu = filp->private_data; 1294 void __user *argp = (void __user *)arg; 1295 struct kvm_device_attr attr; 1296 long r; 1297 1298 switch (ioctl) { 1299 case KVM_ARM_VCPU_INIT: { 1300 struct kvm_vcpu_init init; 1301 1302 r = -EFAULT; 1303 if (copy_from_user(&init, argp, sizeof(init))) 1304 break; 1305 1306 r = kvm_arch_vcpu_ioctl_vcpu_init(vcpu, &init); 1307 break; 1308 } 1309 case KVM_SET_ONE_REG: 1310 case KVM_GET_ONE_REG: { 1311 struct kvm_one_reg reg; 1312 1313 r = -ENOEXEC; 1314 if (unlikely(!kvm_vcpu_initialized(vcpu))) 1315 break; 1316 1317 r = -EFAULT; 1318 if (copy_from_user(®, argp, sizeof(reg))) 1319 break; 1320 1321 /* 1322 * We could owe a reset due to PSCI. Handle the pending reset 1323 * here to ensure userspace register accesses are ordered after 1324 * the reset. 1325 */ 1326 if (kvm_check_request(KVM_REQ_VCPU_RESET, vcpu)) 1327 kvm_reset_vcpu(vcpu); 1328 1329 if (ioctl == KVM_SET_ONE_REG) 1330 r = kvm_arm_set_reg(vcpu, ®); 1331 else 1332 r = kvm_arm_get_reg(vcpu, ®); 1333 break; 1334 } 1335 case KVM_GET_REG_LIST: { 1336 struct kvm_reg_list __user *user_list = argp; 1337 struct kvm_reg_list reg_list; 1338 unsigned n; 1339 1340 r = -ENOEXEC; 1341 if (unlikely(!kvm_vcpu_initialized(vcpu))) 1342 break; 1343 1344 r = -EPERM; 1345 if (!kvm_arm_vcpu_is_finalized(vcpu)) 1346 break; 1347 1348 r = -EFAULT; 1349 if (copy_from_user(®_list, user_list, sizeof(reg_list))) 1350 break; 1351 n = reg_list.n; 1352 reg_list.n = kvm_arm_num_regs(vcpu); 1353 if (copy_to_user(user_list, ®_list, sizeof(reg_list))) 1354 break; 1355 r = -E2BIG; 1356 if (n < reg_list.n) 1357 break; 1358 r = kvm_arm_copy_reg_indices(vcpu, user_list->reg); 1359 break; 1360 } 1361 case KVM_SET_DEVICE_ATTR: { 1362 r = -EFAULT; 1363 if (copy_from_user(&attr, argp, sizeof(attr))) 1364 break; 1365 r = kvm_arm_vcpu_set_attr(vcpu, &attr); 1366 break; 1367 } 1368 case KVM_GET_DEVICE_ATTR: { 1369 r = -EFAULT; 1370 if (copy_from_user(&attr, argp, sizeof(attr))) 1371 break; 1372 r = kvm_arm_vcpu_get_attr(vcpu, &attr); 1373 break; 1374 } 1375 case KVM_HAS_DEVICE_ATTR: { 1376 r = -EFAULT; 1377 if (copy_from_user(&attr, argp, sizeof(attr))) 1378 break; 1379 r = kvm_arm_vcpu_has_attr(vcpu, &attr); 1380 break; 1381 } 1382 case KVM_GET_VCPU_EVENTS: { 1383 struct kvm_vcpu_events events; 1384 1385 if (kvm_arm_vcpu_get_events(vcpu, &events)) 1386 return -EINVAL; 1387 1388 if (copy_to_user(argp, &events, sizeof(events))) 1389 return -EFAULT; 1390 1391 return 0; 1392 } 1393 case KVM_SET_VCPU_EVENTS: { 1394 struct kvm_vcpu_events events; 1395 1396 if (copy_from_user(&events, argp, sizeof(events))) 1397 return -EFAULT; 1398 1399 return kvm_arm_vcpu_set_events(vcpu, &events); 1400 } 1401 case KVM_ARM_VCPU_FINALIZE: { 1402 int what; 1403 1404 if (!kvm_vcpu_initialized(vcpu)) 1405 return -ENOEXEC; 1406 1407 if (get_user(what, (const int __user *)argp)) 1408 return -EFAULT; 1409 1410 return kvm_arm_vcpu_finalize(vcpu, what); 1411 } 1412 default: 1413 r = -EINVAL; 1414 } 1415 1416 return r; 1417 } 1418 1419 void kvm_arch_sync_dirty_log(struct kvm *kvm, struct kvm_memory_slot *memslot) 1420 { 1421 1422 } 1423 1424 void kvm_arch_flush_remote_tlbs_memslot(struct kvm *kvm, 1425 const struct kvm_memory_slot *memslot) 1426 { 1427 kvm_flush_remote_tlbs(kvm); 1428 } 1429 1430 static int kvm_vm_ioctl_set_device_addr(struct kvm *kvm, 1431 struct kvm_arm_device_addr *dev_addr) 1432 { 1433 switch (FIELD_GET(KVM_ARM_DEVICE_ID_MASK, dev_addr->id)) { 1434 case KVM_ARM_DEVICE_VGIC_V2: 1435 if (!vgic_present) 1436 return -ENXIO; 1437 return kvm_set_legacy_vgic_v2_addr(kvm, dev_addr); 1438 default: 1439 return -ENODEV; 1440 } 1441 } 1442 1443 long kvm_arch_vm_ioctl(struct file *filp, 1444 unsigned int ioctl, unsigned long arg) 1445 { 1446 struct kvm *kvm = filp->private_data; 1447 void __user *argp = (void __user *)arg; 1448 1449 switch (ioctl) { 1450 case KVM_CREATE_IRQCHIP: { 1451 int ret; 1452 if (!vgic_present) 1453 return -ENXIO; 1454 mutex_lock(&kvm->lock); 1455 ret = kvm_vgic_create(kvm, KVM_DEV_TYPE_ARM_VGIC_V2); 1456 mutex_unlock(&kvm->lock); 1457 return ret; 1458 } 1459 case KVM_ARM_SET_DEVICE_ADDR: { 1460 struct kvm_arm_device_addr dev_addr; 1461 1462 if (copy_from_user(&dev_addr, argp, sizeof(dev_addr))) 1463 return -EFAULT; 1464 return kvm_vm_ioctl_set_device_addr(kvm, &dev_addr); 1465 } 1466 case KVM_ARM_PREFERRED_TARGET: { 1467 struct kvm_vcpu_init init; 1468 1469 kvm_vcpu_preferred_target(&init); 1470 1471 if (copy_to_user(argp, &init, sizeof(init))) 1472 return -EFAULT; 1473 1474 return 0; 1475 } 1476 case KVM_ARM_MTE_COPY_TAGS: { 1477 struct kvm_arm_copy_mte_tags copy_tags; 1478 1479 if (copy_from_user(©_tags, argp, sizeof(copy_tags))) 1480 return -EFAULT; 1481 return kvm_vm_ioctl_mte_copy_tags(kvm, ©_tags); 1482 } 1483 default: 1484 return -EINVAL; 1485 } 1486 } 1487 1488 static unsigned long nvhe_percpu_size(void) 1489 { 1490 return (unsigned long)CHOOSE_NVHE_SYM(__per_cpu_end) - 1491 (unsigned long)CHOOSE_NVHE_SYM(__per_cpu_start); 1492 } 1493 1494 static unsigned long nvhe_percpu_order(void) 1495 { 1496 unsigned long size = nvhe_percpu_size(); 1497 1498 return size ? get_order(size) : 0; 1499 } 1500 1501 /* A lookup table holding the hypervisor VA for each vector slot */ 1502 static void *hyp_spectre_vector_selector[BP_HARDEN_EL2_SLOTS]; 1503 1504 static void kvm_init_vector_slot(void *base, enum arm64_hyp_spectre_vector slot) 1505 { 1506 hyp_spectre_vector_selector[slot] = __kvm_vector_slot2addr(base, slot); 1507 } 1508 1509 static int kvm_init_vector_slots(void) 1510 { 1511 int err; 1512 void *base; 1513 1514 base = kern_hyp_va(kvm_ksym_ref(__kvm_hyp_vector)); 1515 kvm_init_vector_slot(base, HYP_VECTOR_DIRECT); 1516 1517 base = kern_hyp_va(kvm_ksym_ref(__bp_harden_hyp_vecs)); 1518 kvm_init_vector_slot(base, HYP_VECTOR_SPECTRE_DIRECT); 1519 1520 if (kvm_system_needs_idmapped_vectors() && 1521 !is_protected_kvm_enabled()) { 1522 err = create_hyp_exec_mappings(__pa_symbol(__bp_harden_hyp_vecs), 1523 __BP_HARDEN_HYP_VECS_SZ, &base); 1524 if (err) 1525 return err; 1526 } 1527 1528 kvm_init_vector_slot(base, HYP_VECTOR_INDIRECT); 1529 kvm_init_vector_slot(base, HYP_VECTOR_SPECTRE_INDIRECT); 1530 return 0; 1531 } 1532 1533 static void __init cpu_prepare_hyp_mode(int cpu, u32 hyp_va_bits) 1534 { 1535 struct kvm_nvhe_init_params *params = per_cpu_ptr_nvhe_sym(kvm_init_params, cpu); 1536 unsigned long tcr; 1537 1538 /* 1539 * Calculate the raw per-cpu offset without a translation from the 1540 * kernel's mapping to the linear mapping, and store it in tpidr_el2 1541 * so that we can use adr_l to access per-cpu variables in EL2. 1542 * Also drop the KASAN tag which gets in the way... 1543 */ 1544 params->tpidr_el2 = (unsigned long)kasan_reset_tag(per_cpu_ptr_nvhe_sym(__per_cpu_start, cpu)) - 1545 (unsigned long)kvm_ksym_ref(CHOOSE_NVHE_SYM(__per_cpu_start)); 1546 1547 params->mair_el2 = read_sysreg(mair_el1); 1548 1549 tcr = (read_sysreg(tcr_el1) & TCR_EL2_MASK) | TCR_EL2_RES1; 1550 tcr &= ~TCR_T0SZ_MASK; 1551 tcr |= TCR_T0SZ(hyp_va_bits); 1552 params->tcr_el2 = tcr; 1553 1554 params->pgd_pa = kvm_mmu_get_httbr(); 1555 if (is_protected_kvm_enabled()) 1556 params->hcr_el2 = HCR_HOST_NVHE_PROTECTED_FLAGS; 1557 else 1558 params->hcr_el2 = HCR_HOST_NVHE_FLAGS; 1559 params->vttbr = params->vtcr = 0; 1560 1561 /* 1562 * Flush the init params from the data cache because the struct will 1563 * be read while the MMU is off. 1564 */ 1565 kvm_flush_dcache_to_poc(params, sizeof(*params)); 1566 } 1567 1568 static void hyp_install_host_vector(void) 1569 { 1570 struct kvm_nvhe_init_params *params; 1571 struct arm_smccc_res res; 1572 1573 /* Switch from the HYP stub to our own HYP init vector */ 1574 __hyp_set_vectors(kvm_get_idmap_vector()); 1575 1576 /* 1577 * Call initialization code, and switch to the full blown HYP code. 1578 * If the cpucaps haven't been finalized yet, something has gone very 1579 * wrong, and hyp will crash and burn when it uses any 1580 * cpus_have_const_cap() wrapper. 1581 */ 1582 BUG_ON(!system_capabilities_finalized()); 1583 params = this_cpu_ptr_nvhe_sym(kvm_init_params); 1584 arm_smccc_1_1_hvc(KVM_HOST_SMCCC_FUNC(__kvm_hyp_init), virt_to_phys(params), &res); 1585 WARN_ON(res.a0 != SMCCC_RET_SUCCESS); 1586 } 1587 1588 static void cpu_init_hyp_mode(void) 1589 { 1590 hyp_install_host_vector(); 1591 1592 /* 1593 * Disabling SSBD on a non-VHE system requires us to enable SSBS 1594 * at EL2. 1595 */ 1596 if (this_cpu_has_cap(ARM64_SSBS) && 1597 arm64_get_spectre_v4_state() == SPECTRE_VULNERABLE) { 1598 kvm_call_hyp_nvhe(__kvm_enable_ssbs); 1599 } 1600 } 1601 1602 static void cpu_hyp_reset(void) 1603 { 1604 if (!is_kernel_in_hyp_mode()) 1605 __hyp_reset_vectors(); 1606 } 1607 1608 /* 1609 * EL2 vectors can be mapped and rerouted in a number of ways, 1610 * depending on the kernel configuration and CPU present: 1611 * 1612 * - If the CPU is affected by Spectre-v2, the hardening sequence is 1613 * placed in one of the vector slots, which is executed before jumping 1614 * to the real vectors. 1615 * 1616 * - If the CPU also has the ARM64_SPECTRE_V3A cap, the slot 1617 * containing the hardening sequence is mapped next to the idmap page, 1618 * and executed before jumping to the real vectors. 1619 * 1620 * - If the CPU only has the ARM64_SPECTRE_V3A cap, then an 1621 * empty slot is selected, mapped next to the idmap page, and 1622 * executed before jumping to the real vectors. 1623 * 1624 * Note that ARM64_SPECTRE_V3A is somewhat incompatible with 1625 * VHE, as we don't have hypervisor-specific mappings. If the system 1626 * is VHE and yet selects this capability, it will be ignored. 1627 */ 1628 static void cpu_set_hyp_vector(void) 1629 { 1630 struct bp_hardening_data *data = this_cpu_ptr(&bp_hardening_data); 1631 void *vector = hyp_spectre_vector_selector[data->slot]; 1632 1633 if (!is_protected_kvm_enabled()) 1634 *this_cpu_ptr_hyp_sym(kvm_hyp_vector) = (unsigned long)vector; 1635 else 1636 kvm_call_hyp_nvhe(__pkvm_cpu_set_vector, data->slot); 1637 } 1638 1639 static void cpu_hyp_init_context(void) 1640 { 1641 kvm_init_host_cpu_context(&this_cpu_ptr_hyp_sym(kvm_host_data)->host_ctxt); 1642 1643 if (!is_kernel_in_hyp_mode()) 1644 cpu_init_hyp_mode(); 1645 } 1646 1647 static void cpu_hyp_init_features(void) 1648 { 1649 cpu_set_hyp_vector(); 1650 kvm_arm_init_debug(); 1651 1652 if (is_kernel_in_hyp_mode()) 1653 kvm_timer_init_vhe(); 1654 1655 if (vgic_present) 1656 kvm_vgic_init_cpu_hardware(); 1657 } 1658 1659 static void cpu_hyp_reinit(void) 1660 { 1661 cpu_hyp_reset(); 1662 cpu_hyp_init_context(); 1663 cpu_hyp_init_features(); 1664 } 1665 1666 static void _kvm_arch_hardware_enable(void *discard) 1667 { 1668 if (!__this_cpu_read(kvm_arm_hardware_enabled)) { 1669 cpu_hyp_reinit(); 1670 __this_cpu_write(kvm_arm_hardware_enabled, 1); 1671 } 1672 } 1673 1674 int kvm_arch_hardware_enable(void) 1675 { 1676 int was_enabled = __this_cpu_read(kvm_arm_hardware_enabled); 1677 1678 _kvm_arch_hardware_enable(NULL); 1679 1680 if (!was_enabled) { 1681 kvm_vgic_cpu_up(); 1682 kvm_timer_cpu_up(); 1683 } 1684 1685 return 0; 1686 } 1687 1688 static void _kvm_arch_hardware_disable(void *discard) 1689 { 1690 if (__this_cpu_read(kvm_arm_hardware_enabled)) { 1691 cpu_hyp_reset(); 1692 __this_cpu_write(kvm_arm_hardware_enabled, 0); 1693 } 1694 } 1695 1696 void kvm_arch_hardware_disable(void) 1697 { 1698 if (__this_cpu_read(kvm_arm_hardware_enabled)) { 1699 kvm_timer_cpu_down(); 1700 kvm_vgic_cpu_down(); 1701 } 1702 1703 if (!is_protected_kvm_enabled()) 1704 _kvm_arch_hardware_disable(NULL); 1705 } 1706 1707 #ifdef CONFIG_CPU_PM 1708 static int hyp_init_cpu_pm_notifier(struct notifier_block *self, 1709 unsigned long cmd, 1710 void *v) 1711 { 1712 /* 1713 * kvm_arm_hardware_enabled is left with its old value over 1714 * PM_ENTER->PM_EXIT. It is used to indicate PM_EXIT should 1715 * re-enable hyp. 1716 */ 1717 switch (cmd) { 1718 case CPU_PM_ENTER: 1719 if (__this_cpu_read(kvm_arm_hardware_enabled)) 1720 /* 1721 * don't update kvm_arm_hardware_enabled here 1722 * so that the hardware will be re-enabled 1723 * when we resume. See below. 1724 */ 1725 cpu_hyp_reset(); 1726 1727 return NOTIFY_OK; 1728 case CPU_PM_ENTER_FAILED: 1729 case CPU_PM_EXIT: 1730 if (__this_cpu_read(kvm_arm_hardware_enabled)) 1731 /* The hardware was enabled before suspend. */ 1732 cpu_hyp_reinit(); 1733 1734 return NOTIFY_OK; 1735 1736 default: 1737 return NOTIFY_DONE; 1738 } 1739 } 1740 1741 static struct notifier_block hyp_init_cpu_pm_nb = { 1742 .notifier_call = hyp_init_cpu_pm_notifier, 1743 }; 1744 1745 static void __init hyp_cpu_pm_init(void) 1746 { 1747 if (!is_protected_kvm_enabled()) 1748 cpu_pm_register_notifier(&hyp_init_cpu_pm_nb); 1749 } 1750 static void __init hyp_cpu_pm_exit(void) 1751 { 1752 if (!is_protected_kvm_enabled()) 1753 cpu_pm_unregister_notifier(&hyp_init_cpu_pm_nb); 1754 } 1755 #else 1756 static inline void __init hyp_cpu_pm_init(void) 1757 { 1758 } 1759 static inline void __init hyp_cpu_pm_exit(void) 1760 { 1761 } 1762 #endif 1763 1764 static void __init init_cpu_logical_map(void) 1765 { 1766 unsigned int cpu; 1767 1768 /* 1769 * Copy the MPIDR <-> logical CPU ID mapping to hyp. 1770 * Only copy the set of online CPUs whose features have been checked 1771 * against the finalized system capabilities. The hypervisor will not 1772 * allow any other CPUs from the `possible` set to boot. 1773 */ 1774 for_each_online_cpu(cpu) 1775 hyp_cpu_logical_map[cpu] = cpu_logical_map(cpu); 1776 } 1777 1778 #define init_psci_0_1_impl_state(config, what) \ 1779 config.psci_0_1_ ## what ## _implemented = psci_ops.what 1780 1781 static bool __init init_psci_relay(void) 1782 { 1783 /* 1784 * If PSCI has not been initialized, protected KVM cannot install 1785 * itself on newly booted CPUs. 1786 */ 1787 if (!psci_ops.get_version) { 1788 kvm_err("Cannot initialize protected mode without PSCI\n"); 1789 return false; 1790 } 1791 1792 kvm_host_psci_config.version = psci_ops.get_version(); 1793 1794 if (kvm_host_psci_config.version == PSCI_VERSION(0, 1)) { 1795 kvm_host_psci_config.function_ids_0_1 = get_psci_0_1_function_ids(); 1796 init_psci_0_1_impl_state(kvm_host_psci_config, cpu_suspend); 1797 init_psci_0_1_impl_state(kvm_host_psci_config, cpu_on); 1798 init_psci_0_1_impl_state(kvm_host_psci_config, cpu_off); 1799 init_psci_0_1_impl_state(kvm_host_psci_config, migrate); 1800 } 1801 return true; 1802 } 1803 1804 static int __init init_subsystems(void) 1805 { 1806 int err = 0; 1807 1808 /* 1809 * Enable hardware so that subsystem initialisation can access EL2. 1810 */ 1811 on_each_cpu(_kvm_arch_hardware_enable, NULL, 1); 1812 1813 /* 1814 * Register CPU lower-power notifier 1815 */ 1816 hyp_cpu_pm_init(); 1817 1818 /* 1819 * Init HYP view of VGIC 1820 */ 1821 err = kvm_vgic_hyp_init(); 1822 switch (err) { 1823 case 0: 1824 vgic_present = true; 1825 break; 1826 case -ENODEV: 1827 case -ENXIO: 1828 vgic_present = false; 1829 err = 0; 1830 break; 1831 default: 1832 goto out; 1833 } 1834 1835 /* 1836 * Init HYP architected timer support 1837 */ 1838 err = kvm_timer_hyp_init(vgic_present); 1839 if (err) 1840 goto out; 1841 1842 kvm_register_perf_callbacks(NULL); 1843 1844 out: 1845 if (err) 1846 hyp_cpu_pm_exit(); 1847 1848 if (err || !is_protected_kvm_enabled()) 1849 on_each_cpu(_kvm_arch_hardware_disable, NULL, 1); 1850 1851 return err; 1852 } 1853 1854 static void __init teardown_subsystems(void) 1855 { 1856 kvm_unregister_perf_callbacks(); 1857 hyp_cpu_pm_exit(); 1858 } 1859 1860 static void __init teardown_hyp_mode(void) 1861 { 1862 int cpu; 1863 1864 free_hyp_pgds(); 1865 for_each_possible_cpu(cpu) { 1866 free_page(per_cpu(kvm_arm_hyp_stack_page, cpu)); 1867 free_pages(kvm_nvhe_sym(kvm_arm_hyp_percpu_base)[cpu], nvhe_percpu_order()); 1868 } 1869 } 1870 1871 static int __init do_pkvm_init(u32 hyp_va_bits) 1872 { 1873 void *per_cpu_base = kvm_ksym_ref(kvm_nvhe_sym(kvm_arm_hyp_percpu_base)); 1874 int ret; 1875 1876 preempt_disable(); 1877 cpu_hyp_init_context(); 1878 ret = kvm_call_hyp_nvhe(__pkvm_init, hyp_mem_base, hyp_mem_size, 1879 num_possible_cpus(), kern_hyp_va(per_cpu_base), 1880 hyp_va_bits); 1881 cpu_hyp_init_features(); 1882 1883 /* 1884 * The stub hypercalls are now disabled, so set our local flag to 1885 * prevent a later re-init attempt in kvm_arch_hardware_enable(). 1886 */ 1887 __this_cpu_write(kvm_arm_hardware_enabled, 1); 1888 preempt_enable(); 1889 1890 return ret; 1891 } 1892 1893 static void kvm_hyp_init_symbols(void) 1894 { 1895 kvm_nvhe_sym(id_aa64pfr0_el1_sys_val) = read_sanitised_ftr_reg(SYS_ID_AA64PFR0_EL1); 1896 kvm_nvhe_sym(id_aa64pfr1_el1_sys_val) = read_sanitised_ftr_reg(SYS_ID_AA64PFR1_EL1); 1897 kvm_nvhe_sym(id_aa64isar0_el1_sys_val) = read_sanitised_ftr_reg(SYS_ID_AA64ISAR0_EL1); 1898 kvm_nvhe_sym(id_aa64isar1_el1_sys_val) = read_sanitised_ftr_reg(SYS_ID_AA64ISAR1_EL1); 1899 kvm_nvhe_sym(id_aa64isar2_el1_sys_val) = read_sanitised_ftr_reg(SYS_ID_AA64ISAR2_EL1); 1900 kvm_nvhe_sym(id_aa64mmfr0_el1_sys_val) = read_sanitised_ftr_reg(SYS_ID_AA64MMFR0_EL1); 1901 kvm_nvhe_sym(id_aa64mmfr1_el1_sys_val) = read_sanitised_ftr_reg(SYS_ID_AA64MMFR1_EL1); 1902 kvm_nvhe_sym(id_aa64mmfr2_el1_sys_val) = read_sanitised_ftr_reg(SYS_ID_AA64MMFR2_EL1); 1903 kvm_nvhe_sym(id_aa64smfr0_el1_sys_val) = read_sanitised_ftr_reg(SYS_ID_AA64SMFR0_EL1); 1904 kvm_nvhe_sym(__icache_flags) = __icache_flags; 1905 kvm_nvhe_sym(kvm_arm_vmid_bits) = kvm_arm_vmid_bits; 1906 } 1907 1908 static int __init kvm_hyp_init_protection(u32 hyp_va_bits) 1909 { 1910 void *addr = phys_to_virt(hyp_mem_base); 1911 int ret; 1912 1913 ret = create_hyp_mappings(addr, addr + hyp_mem_size, PAGE_HYP); 1914 if (ret) 1915 return ret; 1916 1917 ret = do_pkvm_init(hyp_va_bits); 1918 if (ret) 1919 return ret; 1920 1921 free_hyp_pgds(); 1922 1923 return 0; 1924 } 1925 1926 /* Inits Hyp-mode on all online CPUs */ 1927 static int __init init_hyp_mode(void) 1928 { 1929 u32 hyp_va_bits; 1930 int cpu; 1931 int err = -ENOMEM; 1932 1933 /* 1934 * The protected Hyp-mode cannot be initialized if the memory pool 1935 * allocation has failed. 1936 */ 1937 if (is_protected_kvm_enabled() && !hyp_mem_base) 1938 goto out_err; 1939 1940 /* 1941 * Allocate Hyp PGD and setup Hyp identity mapping 1942 */ 1943 err = kvm_mmu_init(&hyp_va_bits); 1944 if (err) 1945 goto out_err; 1946 1947 /* 1948 * Allocate stack pages for Hypervisor-mode 1949 */ 1950 for_each_possible_cpu(cpu) { 1951 unsigned long stack_page; 1952 1953 stack_page = __get_free_page(GFP_KERNEL); 1954 if (!stack_page) { 1955 err = -ENOMEM; 1956 goto out_err; 1957 } 1958 1959 per_cpu(kvm_arm_hyp_stack_page, cpu) = stack_page; 1960 } 1961 1962 /* 1963 * Allocate and initialize pages for Hypervisor-mode percpu regions. 1964 */ 1965 for_each_possible_cpu(cpu) { 1966 struct page *page; 1967 void *page_addr; 1968 1969 page = alloc_pages(GFP_KERNEL, nvhe_percpu_order()); 1970 if (!page) { 1971 err = -ENOMEM; 1972 goto out_err; 1973 } 1974 1975 page_addr = page_address(page); 1976 memcpy(page_addr, CHOOSE_NVHE_SYM(__per_cpu_start), nvhe_percpu_size()); 1977 kvm_nvhe_sym(kvm_arm_hyp_percpu_base)[cpu] = (unsigned long)page_addr; 1978 } 1979 1980 /* 1981 * Map the Hyp-code called directly from the host 1982 */ 1983 err = create_hyp_mappings(kvm_ksym_ref(__hyp_text_start), 1984 kvm_ksym_ref(__hyp_text_end), PAGE_HYP_EXEC); 1985 if (err) { 1986 kvm_err("Cannot map world-switch code\n"); 1987 goto out_err; 1988 } 1989 1990 err = create_hyp_mappings(kvm_ksym_ref(__hyp_rodata_start), 1991 kvm_ksym_ref(__hyp_rodata_end), PAGE_HYP_RO); 1992 if (err) { 1993 kvm_err("Cannot map .hyp.rodata section\n"); 1994 goto out_err; 1995 } 1996 1997 err = create_hyp_mappings(kvm_ksym_ref(__start_rodata), 1998 kvm_ksym_ref(__end_rodata), PAGE_HYP_RO); 1999 if (err) { 2000 kvm_err("Cannot map rodata section\n"); 2001 goto out_err; 2002 } 2003 2004 /* 2005 * .hyp.bss is guaranteed to be placed at the beginning of the .bss 2006 * section thanks to an assertion in the linker script. Map it RW and 2007 * the rest of .bss RO. 2008 */ 2009 err = create_hyp_mappings(kvm_ksym_ref(__hyp_bss_start), 2010 kvm_ksym_ref(__hyp_bss_end), PAGE_HYP); 2011 if (err) { 2012 kvm_err("Cannot map hyp bss section: %d\n", err); 2013 goto out_err; 2014 } 2015 2016 err = create_hyp_mappings(kvm_ksym_ref(__hyp_bss_end), 2017 kvm_ksym_ref(__bss_stop), PAGE_HYP_RO); 2018 if (err) { 2019 kvm_err("Cannot map bss section\n"); 2020 goto out_err; 2021 } 2022 2023 /* 2024 * Map the Hyp stack pages 2025 */ 2026 for_each_possible_cpu(cpu) { 2027 struct kvm_nvhe_init_params *params = per_cpu_ptr_nvhe_sym(kvm_init_params, cpu); 2028 char *stack_page = (char *)per_cpu(kvm_arm_hyp_stack_page, cpu); 2029 unsigned long hyp_addr; 2030 2031 /* 2032 * Allocate a contiguous HYP private VA range for the stack 2033 * and guard page. The allocation is also aligned based on 2034 * the order of its size. 2035 */ 2036 err = hyp_alloc_private_va_range(PAGE_SIZE * 2, &hyp_addr); 2037 if (err) { 2038 kvm_err("Cannot allocate hyp stack guard page\n"); 2039 goto out_err; 2040 } 2041 2042 /* 2043 * Since the stack grows downwards, map the stack to the page 2044 * at the higher address and leave the lower guard page 2045 * unbacked. 2046 * 2047 * Any valid stack address now has the PAGE_SHIFT bit as 1 2048 * and addresses corresponding to the guard page have the 2049 * PAGE_SHIFT bit as 0 - this is used for overflow detection. 2050 */ 2051 err = __create_hyp_mappings(hyp_addr + PAGE_SIZE, PAGE_SIZE, 2052 __pa(stack_page), PAGE_HYP); 2053 if (err) { 2054 kvm_err("Cannot map hyp stack\n"); 2055 goto out_err; 2056 } 2057 2058 /* 2059 * Save the stack PA in nvhe_init_params. This will be needed 2060 * to recreate the stack mapping in protected nVHE mode. 2061 * __hyp_pa() won't do the right thing there, since the stack 2062 * has been mapped in the flexible private VA space. 2063 */ 2064 params->stack_pa = __pa(stack_page); 2065 2066 params->stack_hyp_va = hyp_addr + (2 * PAGE_SIZE); 2067 } 2068 2069 for_each_possible_cpu(cpu) { 2070 char *percpu_begin = (char *)kvm_nvhe_sym(kvm_arm_hyp_percpu_base)[cpu]; 2071 char *percpu_end = percpu_begin + nvhe_percpu_size(); 2072 2073 /* Map Hyp percpu pages */ 2074 err = create_hyp_mappings(percpu_begin, percpu_end, PAGE_HYP); 2075 if (err) { 2076 kvm_err("Cannot map hyp percpu region\n"); 2077 goto out_err; 2078 } 2079 2080 /* Prepare the CPU initialization parameters */ 2081 cpu_prepare_hyp_mode(cpu, hyp_va_bits); 2082 } 2083 2084 kvm_hyp_init_symbols(); 2085 2086 if (is_protected_kvm_enabled()) { 2087 init_cpu_logical_map(); 2088 2089 if (!init_psci_relay()) { 2090 err = -ENODEV; 2091 goto out_err; 2092 } 2093 2094 err = kvm_hyp_init_protection(hyp_va_bits); 2095 if (err) { 2096 kvm_err("Failed to init hyp memory protection\n"); 2097 goto out_err; 2098 } 2099 } 2100 2101 return 0; 2102 2103 out_err: 2104 teardown_hyp_mode(); 2105 kvm_err("error initializing Hyp mode: %d\n", err); 2106 return err; 2107 } 2108 2109 static void __init _kvm_host_prot_finalize(void *arg) 2110 { 2111 int *err = arg; 2112 2113 if (WARN_ON(kvm_call_hyp_nvhe(__pkvm_prot_finalize))) 2114 WRITE_ONCE(*err, -EINVAL); 2115 } 2116 2117 static int __init pkvm_drop_host_privileges(void) 2118 { 2119 int ret = 0; 2120 2121 /* 2122 * Flip the static key upfront as that may no longer be possible 2123 * once the host stage 2 is installed. 2124 */ 2125 static_branch_enable(&kvm_protected_mode_initialized); 2126 on_each_cpu(_kvm_host_prot_finalize, &ret, 1); 2127 return ret; 2128 } 2129 2130 static int __init finalize_hyp_mode(void) 2131 { 2132 if (!is_protected_kvm_enabled()) 2133 return 0; 2134 2135 /* 2136 * Exclude HYP sections from kmemleak so that they don't get peeked 2137 * at, which would end badly once inaccessible. 2138 */ 2139 kmemleak_free_part(__hyp_bss_start, __hyp_bss_end - __hyp_bss_start); 2140 kmemleak_free_part_phys(hyp_mem_base, hyp_mem_size); 2141 return pkvm_drop_host_privileges(); 2142 } 2143 2144 struct kvm_vcpu *kvm_mpidr_to_vcpu(struct kvm *kvm, unsigned long mpidr) 2145 { 2146 struct kvm_vcpu *vcpu; 2147 unsigned long i; 2148 2149 mpidr &= MPIDR_HWID_BITMASK; 2150 kvm_for_each_vcpu(i, vcpu, kvm) { 2151 if (mpidr == kvm_vcpu_get_mpidr_aff(vcpu)) 2152 return vcpu; 2153 } 2154 return NULL; 2155 } 2156 2157 bool kvm_arch_irqchip_in_kernel(struct kvm *kvm) 2158 { 2159 return irqchip_in_kernel(kvm); 2160 } 2161 2162 bool kvm_arch_has_irq_bypass(void) 2163 { 2164 return true; 2165 } 2166 2167 int kvm_arch_irq_bypass_add_producer(struct irq_bypass_consumer *cons, 2168 struct irq_bypass_producer *prod) 2169 { 2170 struct kvm_kernel_irqfd *irqfd = 2171 container_of(cons, struct kvm_kernel_irqfd, consumer); 2172 2173 return kvm_vgic_v4_set_forwarding(irqfd->kvm, prod->irq, 2174 &irqfd->irq_entry); 2175 } 2176 void kvm_arch_irq_bypass_del_producer(struct irq_bypass_consumer *cons, 2177 struct irq_bypass_producer *prod) 2178 { 2179 struct kvm_kernel_irqfd *irqfd = 2180 container_of(cons, struct kvm_kernel_irqfd, consumer); 2181 2182 kvm_vgic_v4_unset_forwarding(irqfd->kvm, prod->irq, 2183 &irqfd->irq_entry); 2184 } 2185 2186 void kvm_arch_irq_bypass_stop(struct irq_bypass_consumer *cons) 2187 { 2188 struct kvm_kernel_irqfd *irqfd = 2189 container_of(cons, struct kvm_kernel_irqfd, consumer); 2190 2191 kvm_arm_halt_guest(irqfd->kvm); 2192 } 2193 2194 void kvm_arch_irq_bypass_start(struct irq_bypass_consumer *cons) 2195 { 2196 struct kvm_kernel_irqfd *irqfd = 2197 container_of(cons, struct kvm_kernel_irqfd, consumer); 2198 2199 kvm_arm_resume_guest(irqfd->kvm); 2200 } 2201 2202 /* Initialize Hyp-mode and memory mappings on all CPUs */ 2203 static __init int kvm_arm_init(void) 2204 { 2205 int err; 2206 bool in_hyp_mode; 2207 2208 if (!is_hyp_mode_available()) { 2209 kvm_info("HYP mode not available\n"); 2210 return -ENODEV; 2211 } 2212 2213 if (kvm_get_mode() == KVM_MODE_NONE) { 2214 kvm_info("KVM disabled from command line\n"); 2215 return -ENODEV; 2216 } 2217 2218 err = kvm_sys_reg_table_init(); 2219 if (err) { 2220 kvm_info("Error initializing system register tables"); 2221 return err; 2222 } 2223 2224 in_hyp_mode = is_kernel_in_hyp_mode(); 2225 2226 if (cpus_have_final_cap(ARM64_WORKAROUND_DEVICE_LOAD_ACQUIRE) || 2227 cpus_have_final_cap(ARM64_WORKAROUND_1508412)) 2228 kvm_info("Guests without required CPU erratum workarounds can deadlock system!\n" \ 2229 "Only trusted guests should be used on this system.\n"); 2230 2231 err = kvm_set_ipa_limit(); 2232 if (err) 2233 return err; 2234 2235 err = kvm_arm_init_sve(); 2236 if (err) 2237 return err; 2238 2239 err = kvm_arm_vmid_alloc_init(); 2240 if (err) { 2241 kvm_err("Failed to initialize VMID allocator.\n"); 2242 return err; 2243 } 2244 2245 if (!in_hyp_mode) { 2246 err = init_hyp_mode(); 2247 if (err) 2248 goto out_err; 2249 } 2250 2251 err = kvm_init_vector_slots(); 2252 if (err) { 2253 kvm_err("Cannot initialise vector slots\n"); 2254 goto out_hyp; 2255 } 2256 2257 err = init_subsystems(); 2258 if (err) 2259 goto out_hyp; 2260 2261 if (!in_hyp_mode) { 2262 err = finalize_hyp_mode(); 2263 if (err) { 2264 kvm_err("Failed to finalize Hyp protection\n"); 2265 goto out_subs; 2266 } 2267 } 2268 2269 if (is_protected_kvm_enabled()) { 2270 kvm_info("Protected nVHE mode initialized successfully\n"); 2271 } else if (in_hyp_mode) { 2272 kvm_info("VHE mode initialized successfully\n"); 2273 } else { 2274 kvm_info("Hyp mode initialized successfully\n"); 2275 } 2276 2277 /* 2278 * FIXME: Do something reasonable if kvm_init() fails after pKVM 2279 * hypervisor protection is finalized. 2280 */ 2281 err = kvm_init(sizeof(struct kvm_vcpu), 0, THIS_MODULE); 2282 if (err) 2283 goto out_subs; 2284 2285 return 0; 2286 2287 out_subs: 2288 teardown_subsystems(); 2289 out_hyp: 2290 if (!in_hyp_mode) 2291 teardown_hyp_mode(); 2292 out_err: 2293 kvm_arm_vmid_alloc_free(); 2294 return err; 2295 } 2296 2297 static int __init early_kvm_mode_cfg(char *arg) 2298 { 2299 if (!arg) 2300 return -EINVAL; 2301 2302 if (strcmp(arg, "none") == 0) { 2303 kvm_mode = KVM_MODE_NONE; 2304 return 0; 2305 } 2306 2307 if (!is_hyp_mode_available()) { 2308 pr_warn_once("KVM is not available. Ignoring kvm-arm.mode\n"); 2309 return 0; 2310 } 2311 2312 if (strcmp(arg, "protected") == 0) { 2313 if (!is_kernel_in_hyp_mode()) 2314 kvm_mode = KVM_MODE_PROTECTED; 2315 else 2316 pr_warn_once("Protected KVM not available with VHE\n"); 2317 2318 return 0; 2319 } 2320 2321 if (strcmp(arg, "nvhe") == 0 && !WARN_ON(is_kernel_in_hyp_mode())) { 2322 kvm_mode = KVM_MODE_DEFAULT; 2323 return 0; 2324 } 2325 2326 if (strcmp(arg, "nested") == 0 && !WARN_ON(!is_kernel_in_hyp_mode())) { 2327 kvm_mode = KVM_MODE_NV; 2328 return 0; 2329 } 2330 2331 return -EINVAL; 2332 } 2333 early_param("kvm-arm.mode", early_kvm_mode_cfg); 2334 2335 enum kvm_mode kvm_get_mode(void) 2336 { 2337 return kvm_mode; 2338 } 2339 2340 module_init(kvm_arm_init); 2341