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_arch_hardware_setup(void *opaque) 67 { 68 return 0; 69 } 70 71 int kvm_arch_check_processor_compat(void *opaque) 72 { 73 return 0; 74 } 75 76 int kvm_vm_ioctl_enable_cap(struct kvm *kvm, 77 struct kvm_enable_cap *cap) 78 { 79 int r; 80 81 if (cap->flags) 82 return -EINVAL; 83 84 switch (cap->cap) { 85 case KVM_CAP_ARM_NISV_TO_USER: 86 r = 0; 87 set_bit(KVM_ARCH_FLAG_RETURN_NISV_IO_ABORT_TO_USER, 88 &kvm->arch.flags); 89 break; 90 case KVM_CAP_ARM_MTE: 91 mutex_lock(&kvm->lock); 92 if (!system_supports_mte() || kvm->created_vcpus) { 93 r = -EINVAL; 94 } else { 95 r = 0; 96 set_bit(KVM_ARCH_FLAG_MTE_ENABLED, &kvm->arch.flags); 97 } 98 mutex_unlock(&kvm->lock); 99 break; 100 case KVM_CAP_ARM_SYSTEM_SUSPEND: 101 r = 0; 102 set_bit(KVM_ARCH_FLAG_SYSTEM_SUSPEND_ENABLED, &kvm->arch.flags); 103 break; 104 default: 105 r = -EINVAL; 106 break; 107 } 108 109 return r; 110 } 111 112 static int kvm_arm_default_max_vcpus(void) 113 { 114 return vgic_present ? kvm_vgic_get_max_vcpus() : KVM_MAX_VCPUS; 115 } 116 117 static void set_default_spectre(struct kvm *kvm) 118 { 119 /* 120 * The default is to expose CSV2 == 1 if the HW isn't affected. 121 * Although this is a per-CPU feature, we make it global because 122 * asymmetric systems are just a nuisance. 123 * 124 * Userspace can override this as long as it doesn't promise 125 * the impossible. 126 */ 127 if (arm64_get_spectre_v2_state() == SPECTRE_UNAFFECTED) 128 kvm->arch.pfr0_csv2 = 1; 129 if (arm64_get_meltdown_state() == SPECTRE_UNAFFECTED) 130 kvm->arch.pfr0_csv3 = 1; 131 } 132 133 /** 134 * kvm_arch_init_vm - initializes a VM data structure 135 * @kvm: pointer to the KVM struct 136 */ 137 int kvm_arch_init_vm(struct kvm *kvm, unsigned long type) 138 { 139 int ret; 140 141 ret = kvm_share_hyp(kvm, kvm + 1); 142 if (ret) 143 return ret; 144 145 ret = pkvm_init_host_vm(kvm); 146 if (ret) 147 goto err_unshare_kvm; 148 149 if (!zalloc_cpumask_var(&kvm->arch.supported_cpus, GFP_KERNEL)) { 150 ret = -ENOMEM; 151 goto err_unshare_kvm; 152 } 153 cpumask_copy(kvm->arch.supported_cpus, cpu_possible_mask); 154 155 ret = kvm_init_stage2_mmu(kvm, &kvm->arch.mmu, type); 156 if (ret) 157 goto err_free_cpumask; 158 159 kvm_vgic_early_init(kvm); 160 161 /* The maximum number of VCPUs is limited by the host's GIC model */ 162 kvm->max_vcpus = kvm_arm_default_max_vcpus(); 163 164 set_default_spectre(kvm); 165 kvm_arm_init_hypercalls(kvm); 166 167 /* 168 * Initialise the default PMUver before there is a chance to 169 * create an actual PMU. 170 */ 171 kvm->arch.dfr0_pmuver.imp = kvm_arm_pmu_get_pmuver_limit(); 172 173 return 0; 174 175 err_free_cpumask: 176 free_cpumask_var(kvm->arch.supported_cpus); 177 err_unshare_kvm: 178 kvm_unshare_hyp(kvm, kvm + 1); 179 return ret; 180 } 181 182 vm_fault_t kvm_arch_vcpu_fault(struct kvm_vcpu *vcpu, struct vm_fault *vmf) 183 { 184 return VM_FAULT_SIGBUS; 185 } 186 187 188 /** 189 * kvm_arch_destroy_vm - destroy the VM data structure 190 * @kvm: pointer to the KVM struct 191 */ 192 void kvm_arch_destroy_vm(struct kvm *kvm) 193 { 194 bitmap_free(kvm->arch.pmu_filter); 195 free_cpumask_var(kvm->arch.supported_cpus); 196 197 kvm_vgic_destroy(kvm); 198 199 if (is_protected_kvm_enabled()) 200 pkvm_destroy_hyp_vm(kvm); 201 202 kvm_destroy_vcpus(kvm); 203 204 kvm_unshare_hyp(kvm, kvm + 1); 205 } 206 207 int kvm_vm_ioctl_check_extension(struct kvm *kvm, long ext) 208 { 209 int r; 210 switch (ext) { 211 case KVM_CAP_IRQCHIP: 212 r = vgic_present; 213 break; 214 case KVM_CAP_IOEVENTFD: 215 case KVM_CAP_DEVICE_CTRL: 216 case KVM_CAP_USER_MEMORY: 217 case KVM_CAP_SYNC_MMU: 218 case KVM_CAP_DESTROY_MEMORY_REGION_WORKS: 219 case KVM_CAP_ONE_REG: 220 case KVM_CAP_ARM_PSCI: 221 case KVM_CAP_ARM_PSCI_0_2: 222 case KVM_CAP_READONLY_MEM: 223 case KVM_CAP_MP_STATE: 224 case KVM_CAP_IMMEDIATE_EXIT: 225 case KVM_CAP_VCPU_EVENTS: 226 case KVM_CAP_ARM_IRQ_LINE_LAYOUT_2: 227 case KVM_CAP_ARM_NISV_TO_USER: 228 case KVM_CAP_ARM_INJECT_EXT_DABT: 229 case KVM_CAP_SET_GUEST_DEBUG: 230 case KVM_CAP_VCPU_ATTRIBUTES: 231 case KVM_CAP_PTP_KVM: 232 case KVM_CAP_ARM_SYSTEM_SUSPEND: 233 r = 1; 234 break; 235 case KVM_CAP_SET_GUEST_DEBUG2: 236 return KVM_GUESTDBG_VALID_MASK; 237 case KVM_CAP_ARM_SET_DEVICE_ADDR: 238 r = 1; 239 break; 240 case KVM_CAP_NR_VCPUS: 241 /* 242 * ARM64 treats KVM_CAP_NR_CPUS differently from all other 243 * architectures, as it does not always bound it to 244 * KVM_CAP_MAX_VCPUS. It should not matter much because 245 * this is just an advisory value. 246 */ 247 r = min_t(unsigned int, num_online_cpus(), 248 kvm_arm_default_max_vcpus()); 249 break; 250 case KVM_CAP_MAX_VCPUS: 251 case KVM_CAP_MAX_VCPU_ID: 252 if (kvm) 253 r = kvm->max_vcpus; 254 else 255 r = kvm_arm_default_max_vcpus(); 256 break; 257 case KVM_CAP_MSI_DEVID: 258 if (!kvm) 259 r = -EINVAL; 260 else 261 r = kvm->arch.vgic.msis_require_devid; 262 break; 263 case KVM_CAP_ARM_USER_IRQ: 264 /* 265 * 1: EL1_VTIMER, EL1_PTIMER, and PMU. 266 * (bump this number if adding more devices) 267 */ 268 r = 1; 269 break; 270 case KVM_CAP_ARM_MTE: 271 r = system_supports_mte(); 272 break; 273 case KVM_CAP_STEAL_TIME: 274 r = kvm_arm_pvtime_supported(); 275 break; 276 case KVM_CAP_ARM_EL1_32BIT: 277 r = cpus_have_const_cap(ARM64_HAS_32BIT_EL1); 278 break; 279 case KVM_CAP_GUEST_DEBUG_HW_BPS: 280 r = get_num_brps(); 281 break; 282 case KVM_CAP_GUEST_DEBUG_HW_WPS: 283 r = get_num_wrps(); 284 break; 285 case KVM_CAP_ARM_PMU_V3: 286 r = kvm_arm_support_pmu_v3(); 287 break; 288 case KVM_CAP_ARM_INJECT_SERROR_ESR: 289 r = cpus_have_const_cap(ARM64_HAS_RAS_EXTN); 290 break; 291 case KVM_CAP_ARM_VM_IPA_SIZE: 292 r = get_kvm_ipa_limit(); 293 break; 294 case KVM_CAP_ARM_SVE: 295 r = system_supports_sve(); 296 break; 297 case KVM_CAP_ARM_PTRAUTH_ADDRESS: 298 case KVM_CAP_ARM_PTRAUTH_GENERIC: 299 r = system_has_full_ptr_auth(); 300 break; 301 default: 302 r = 0; 303 } 304 305 return r; 306 } 307 308 long kvm_arch_dev_ioctl(struct file *filp, 309 unsigned int ioctl, unsigned long arg) 310 { 311 return -EINVAL; 312 } 313 314 struct kvm *kvm_arch_alloc_vm(void) 315 { 316 size_t sz = sizeof(struct kvm); 317 318 if (!has_vhe()) 319 return kzalloc(sz, GFP_KERNEL_ACCOUNT); 320 321 return __vmalloc(sz, GFP_KERNEL_ACCOUNT | __GFP_HIGHMEM | __GFP_ZERO); 322 } 323 324 int kvm_arch_vcpu_precreate(struct kvm *kvm, unsigned int id) 325 { 326 if (irqchip_in_kernel(kvm) && vgic_initialized(kvm)) 327 return -EBUSY; 328 329 if (id >= kvm->max_vcpus) 330 return -EINVAL; 331 332 return 0; 333 } 334 335 int kvm_arch_vcpu_create(struct kvm_vcpu *vcpu) 336 { 337 int err; 338 339 /* Force users to call KVM_ARM_VCPU_INIT */ 340 vcpu->arch.target = -1; 341 bitmap_zero(vcpu->arch.features, KVM_VCPU_MAX_FEATURES); 342 343 vcpu->arch.mmu_page_cache.gfp_zero = __GFP_ZERO; 344 345 /* 346 * Default value for the FP state, will be overloaded at load 347 * time if we support FP (pretty likely) 348 */ 349 vcpu->arch.fp_state = FP_STATE_FREE; 350 351 /* Set up the timer */ 352 kvm_timer_vcpu_init(vcpu); 353 354 kvm_pmu_vcpu_init(vcpu); 355 356 kvm_arm_reset_debug_ptr(vcpu); 357 358 kvm_arm_pvtime_vcpu_init(&vcpu->arch); 359 360 vcpu->arch.hw_mmu = &vcpu->kvm->arch.mmu; 361 362 err = kvm_vgic_vcpu_init(vcpu); 363 if (err) 364 return err; 365 366 return kvm_share_hyp(vcpu, vcpu + 1); 367 } 368 369 void kvm_arch_vcpu_postcreate(struct kvm_vcpu *vcpu) 370 { 371 } 372 373 void kvm_arch_vcpu_destroy(struct kvm_vcpu *vcpu) 374 { 375 if (vcpu_has_run_once(vcpu) && unlikely(!irqchip_in_kernel(vcpu->kvm))) 376 static_branch_dec(&userspace_irqchip_in_use); 377 378 kvm_mmu_free_memory_cache(&vcpu->arch.mmu_page_cache); 379 kvm_timer_vcpu_terminate(vcpu); 380 kvm_pmu_vcpu_destroy(vcpu); 381 382 kvm_arm_vcpu_destroy(vcpu); 383 } 384 385 void kvm_arch_vcpu_blocking(struct kvm_vcpu *vcpu) 386 { 387 388 } 389 390 void kvm_arch_vcpu_unblocking(struct kvm_vcpu *vcpu) 391 { 392 393 } 394 395 void kvm_arch_vcpu_load(struct kvm_vcpu *vcpu, int cpu) 396 { 397 struct kvm_s2_mmu *mmu; 398 int *last_ran; 399 400 mmu = vcpu->arch.hw_mmu; 401 last_ran = this_cpu_ptr(mmu->last_vcpu_ran); 402 403 /* 404 * We guarantee that both TLBs and I-cache are private to each 405 * vcpu. If detecting that a vcpu from the same VM has 406 * previously run on the same physical CPU, call into the 407 * hypervisor code to nuke the relevant contexts. 408 * 409 * We might get preempted before the vCPU actually runs, but 410 * over-invalidation doesn't affect correctness. 411 */ 412 if (*last_ran != vcpu->vcpu_id) { 413 kvm_call_hyp(__kvm_flush_cpu_context, mmu); 414 *last_ran = vcpu->vcpu_id; 415 } 416 417 vcpu->cpu = cpu; 418 419 kvm_vgic_load(vcpu); 420 kvm_timer_vcpu_load(vcpu); 421 if (has_vhe()) 422 kvm_vcpu_load_sysregs_vhe(vcpu); 423 kvm_arch_vcpu_load_fp(vcpu); 424 kvm_vcpu_pmu_restore_guest(vcpu); 425 if (kvm_arm_is_pvtime_enabled(&vcpu->arch)) 426 kvm_make_request(KVM_REQ_RECORD_STEAL, vcpu); 427 428 if (single_task_running()) 429 vcpu_clear_wfx_traps(vcpu); 430 else 431 vcpu_set_wfx_traps(vcpu); 432 433 if (vcpu_has_ptrauth(vcpu)) 434 vcpu_ptrauth_disable(vcpu); 435 kvm_arch_vcpu_load_debug_state_flags(vcpu); 436 437 if (!cpumask_test_cpu(smp_processor_id(), vcpu->kvm->arch.supported_cpus)) 438 vcpu_set_on_unsupported_cpu(vcpu); 439 } 440 441 void kvm_arch_vcpu_put(struct kvm_vcpu *vcpu) 442 { 443 kvm_arch_vcpu_put_debug_state_flags(vcpu); 444 kvm_arch_vcpu_put_fp(vcpu); 445 if (has_vhe()) 446 kvm_vcpu_put_sysregs_vhe(vcpu); 447 kvm_timer_vcpu_put(vcpu); 448 kvm_vgic_put(vcpu); 449 kvm_vcpu_pmu_restore_host(vcpu); 450 kvm_arm_vmid_clear_active(); 451 452 vcpu_clear_on_unsupported_cpu(vcpu); 453 vcpu->cpu = -1; 454 } 455 456 void kvm_arm_vcpu_power_off(struct kvm_vcpu *vcpu) 457 { 458 vcpu->arch.mp_state.mp_state = KVM_MP_STATE_STOPPED; 459 kvm_make_request(KVM_REQ_SLEEP, vcpu); 460 kvm_vcpu_kick(vcpu); 461 } 462 463 bool kvm_arm_vcpu_stopped(struct kvm_vcpu *vcpu) 464 { 465 return vcpu->arch.mp_state.mp_state == KVM_MP_STATE_STOPPED; 466 } 467 468 static void kvm_arm_vcpu_suspend(struct kvm_vcpu *vcpu) 469 { 470 vcpu->arch.mp_state.mp_state = KVM_MP_STATE_SUSPENDED; 471 kvm_make_request(KVM_REQ_SUSPEND, vcpu); 472 kvm_vcpu_kick(vcpu); 473 } 474 475 static bool kvm_arm_vcpu_suspended(struct kvm_vcpu *vcpu) 476 { 477 return vcpu->arch.mp_state.mp_state == KVM_MP_STATE_SUSPENDED; 478 } 479 480 int kvm_arch_vcpu_ioctl_get_mpstate(struct kvm_vcpu *vcpu, 481 struct kvm_mp_state *mp_state) 482 { 483 *mp_state = vcpu->arch.mp_state; 484 485 return 0; 486 } 487 488 int kvm_arch_vcpu_ioctl_set_mpstate(struct kvm_vcpu *vcpu, 489 struct kvm_mp_state *mp_state) 490 { 491 int ret = 0; 492 493 switch (mp_state->mp_state) { 494 case KVM_MP_STATE_RUNNABLE: 495 vcpu->arch.mp_state = *mp_state; 496 break; 497 case KVM_MP_STATE_STOPPED: 498 kvm_arm_vcpu_power_off(vcpu); 499 break; 500 case KVM_MP_STATE_SUSPENDED: 501 kvm_arm_vcpu_suspend(vcpu); 502 break; 503 default: 504 ret = -EINVAL; 505 } 506 507 return ret; 508 } 509 510 /** 511 * kvm_arch_vcpu_runnable - determine if the vcpu can be scheduled 512 * @v: The VCPU pointer 513 * 514 * If the guest CPU is not waiting for interrupts or an interrupt line is 515 * asserted, the CPU is by definition runnable. 516 */ 517 int kvm_arch_vcpu_runnable(struct kvm_vcpu *v) 518 { 519 bool irq_lines = *vcpu_hcr(v) & (HCR_VI | HCR_VF); 520 return ((irq_lines || kvm_vgic_vcpu_pending_irq(v)) 521 && !kvm_arm_vcpu_stopped(v) && !v->arch.pause); 522 } 523 524 bool kvm_arch_vcpu_in_kernel(struct kvm_vcpu *vcpu) 525 { 526 return vcpu_mode_priv(vcpu); 527 } 528 529 #ifdef CONFIG_GUEST_PERF_EVENTS 530 unsigned long kvm_arch_vcpu_get_ip(struct kvm_vcpu *vcpu) 531 { 532 return *vcpu_pc(vcpu); 533 } 534 #endif 535 536 static int kvm_vcpu_initialized(struct kvm_vcpu *vcpu) 537 { 538 return vcpu->arch.target >= 0; 539 } 540 541 /* 542 * Handle both the initialisation that is being done when the vcpu is 543 * run for the first time, as well as the updates that must be 544 * performed each time we get a new thread dealing with this vcpu. 545 */ 546 int kvm_arch_vcpu_run_pid_change(struct kvm_vcpu *vcpu) 547 { 548 struct kvm *kvm = vcpu->kvm; 549 int ret; 550 551 if (!kvm_vcpu_initialized(vcpu)) 552 return -ENOEXEC; 553 554 if (!kvm_arm_vcpu_is_finalized(vcpu)) 555 return -EPERM; 556 557 ret = kvm_arch_vcpu_run_map_fp(vcpu); 558 if (ret) 559 return ret; 560 561 if (likely(vcpu_has_run_once(vcpu))) 562 return 0; 563 564 kvm_arm_vcpu_init_debug(vcpu); 565 566 if (likely(irqchip_in_kernel(kvm))) { 567 /* 568 * Map the VGIC hardware resources before running a vcpu the 569 * first time on this VM. 570 */ 571 ret = kvm_vgic_map_resources(kvm); 572 if (ret) 573 return ret; 574 } 575 576 ret = kvm_timer_enable(vcpu); 577 if (ret) 578 return ret; 579 580 ret = kvm_arm_pmu_v3_enable(vcpu); 581 if (ret) 582 return ret; 583 584 if (is_protected_kvm_enabled()) { 585 ret = pkvm_create_hyp_vm(kvm); 586 if (ret) 587 return ret; 588 } 589 590 if (!irqchip_in_kernel(kvm)) { 591 /* 592 * Tell the rest of the code that there are userspace irqchip 593 * VMs in the wild. 594 */ 595 static_branch_inc(&userspace_irqchip_in_use); 596 } 597 598 /* 599 * Initialize traps for protected VMs. 600 * NOTE: Move to run in EL2 directly, rather than via a hypercall, once 601 * the code is in place for first run initialization at EL2. 602 */ 603 if (kvm_vm_is_protected(kvm)) 604 kvm_call_hyp_nvhe(__pkvm_vcpu_init_traps, vcpu); 605 606 mutex_lock(&kvm->lock); 607 set_bit(KVM_ARCH_FLAG_HAS_RAN_ONCE, &kvm->arch.flags); 608 mutex_unlock(&kvm->lock); 609 610 return ret; 611 } 612 613 bool kvm_arch_intc_initialized(struct kvm *kvm) 614 { 615 return vgic_initialized(kvm); 616 } 617 618 void kvm_arm_halt_guest(struct kvm *kvm) 619 { 620 unsigned long i; 621 struct kvm_vcpu *vcpu; 622 623 kvm_for_each_vcpu(i, vcpu, kvm) 624 vcpu->arch.pause = true; 625 kvm_make_all_cpus_request(kvm, KVM_REQ_SLEEP); 626 } 627 628 void kvm_arm_resume_guest(struct kvm *kvm) 629 { 630 unsigned long i; 631 struct kvm_vcpu *vcpu; 632 633 kvm_for_each_vcpu(i, vcpu, kvm) { 634 vcpu->arch.pause = false; 635 __kvm_vcpu_wake_up(vcpu); 636 } 637 } 638 639 static void kvm_vcpu_sleep(struct kvm_vcpu *vcpu) 640 { 641 struct rcuwait *wait = kvm_arch_vcpu_get_wait(vcpu); 642 643 rcuwait_wait_event(wait, 644 (!kvm_arm_vcpu_stopped(vcpu)) && (!vcpu->arch.pause), 645 TASK_INTERRUPTIBLE); 646 647 if (kvm_arm_vcpu_stopped(vcpu) || vcpu->arch.pause) { 648 /* Awaken to handle a signal, request we sleep again later. */ 649 kvm_make_request(KVM_REQ_SLEEP, vcpu); 650 } 651 652 /* 653 * Make sure we will observe a potential reset request if we've 654 * observed a change to the power state. Pairs with the smp_wmb() in 655 * kvm_psci_vcpu_on(). 656 */ 657 smp_rmb(); 658 } 659 660 /** 661 * kvm_vcpu_wfi - emulate Wait-For-Interrupt behavior 662 * @vcpu: The VCPU pointer 663 * 664 * Suspend execution of a vCPU until a valid wake event is detected, i.e. until 665 * the vCPU is runnable. The vCPU may or may not be scheduled out, depending 666 * on when a wake event arrives, e.g. there may already be a pending wake event. 667 */ 668 void kvm_vcpu_wfi(struct kvm_vcpu *vcpu) 669 { 670 /* 671 * Sync back the state of the GIC CPU interface so that we have 672 * the latest PMR and group enables. This ensures that 673 * kvm_arch_vcpu_runnable has up-to-date data to decide whether 674 * we have pending interrupts, e.g. when determining if the 675 * vCPU should block. 676 * 677 * For the same reason, we want to tell GICv4 that we need 678 * doorbells to be signalled, should an interrupt become pending. 679 */ 680 preempt_disable(); 681 kvm_vgic_vmcr_sync(vcpu); 682 vgic_v4_put(vcpu, true); 683 preempt_enable(); 684 685 kvm_vcpu_halt(vcpu); 686 vcpu_clear_flag(vcpu, IN_WFIT); 687 688 preempt_disable(); 689 vgic_v4_load(vcpu); 690 preempt_enable(); 691 } 692 693 static int kvm_vcpu_suspend(struct kvm_vcpu *vcpu) 694 { 695 if (!kvm_arm_vcpu_suspended(vcpu)) 696 return 1; 697 698 kvm_vcpu_wfi(vcpu); 699 700 /* 701 * The suspend state is sticky; we do not leave it until userspace 702 * explicitly marks the vCPU as runnable. Request that we suspend again 703 * later. 704 */ 705 kvm_make_request(KVM_REQ_SUSPEND, vcpu); 706 707 /* 708 * Check to make sure the vCPU is actually runnable. If so, exit to 709 * userspace informing it of the wakeup condition. 710 */ 711 if (kvm_arch_vcpu_runnable(vcpu)) { 712 memset(&vcpu->run->system_event, 0, sizeof(vcpu->run->system_event)); 713 vcpu->run->system_event.type = KVM_SYSTEM_EVENT_WAKEUP; 714 vcpu->run->exit_reason = KVM_EXIT_SYSTEM_EVENT; 715 return 0; 716 } 717 718 /* 719 * Otherwise, we were unblocked to process a different event, such as a 720 * pending signal. Return 1 and allow kvm_arch_vcpu_ioctl_run() to 721 * process the event. 722 */ 723 return 1; 724 } 725 726 /** 727 * check_vcpu_requests - check and handle pending vCPU requests 728 * @vcpu: the VCPU pointer 729 * 730 * Return: 1 if we should enter the guest 731 * 0 if we should exit to userspace 732 * < 0 if we should exit to userspace, where the return value indicates 733 * an error 734 */ 735 static int check_vcpu_requests(struct kvm_vcpu *vcpu) 736 { 737 if (kvm_request_pending(vcpu)) { 738 if (kvm_check_request(KVM_REQ_SLEEP, vcpu)) 739 kvm_vcpu_sleep(vcpu); 740 741 if (kvm_check_request(KVM_REQ_VCPU_RESET, vcpu)) 742 kvm_reset_vcpu(vcpu); 743 744 /* 745 * Clear IRQ_PENDING requests that were made to guarantee 746 * that a VCPU sees new virtual interrupts. 747 */ 748 kvm_check_request(KVM_REQ_IRQ_PENDING, vcpu); 749 750 if (kvm_check_request(KVM_REQ_RECORD_STEAL, vcpu)) 751 kvm_update_stolen_time(vcpu); 752 753 if (kvm_check_request(KVM_REQ_RELOAD_GICv4, vcpu)) { 754 /* The distributor enable bits were changed */ 755 preempt_disable(); 756 vgic_v4_put(vcpu, false); 757 vgic_v4_load(vcpu); 758 preempt_enable(); 759 } 760 761 if (kvm_check_request(KVM_REQ_RELOAD_PMU, vcpu)) 762 kvm_pmu_handle_pmcr(vcpu, 763 __vcpu_sys_reg(vcpu, PMCR_EL0)); 764 765 if (kvm_check_request(KVM_REQ_SUSPEND, vcpu)) 766 return kvm_vcpu_suspend(vcpu); 767 768 if (kvm_dirty_ring_check_request(vcpu)) 769 return 0; 770 } 771 772 return 1; 773 } 774 775 static bool vcpu_mode_is_bad_32bit(struct kvm_vcpu *vcpu) 776 { 777 if (likely(!vcpu_mode_is_32bit(vcpu))) 778 return false; 779 780 return !kvm_supports_32bit_el0(); 781 } 782 783 /** 784 * kvm_vcpu_exit_request - returns true if the VCPU should *not* enter the guest 785 * @vcpu: The VCPU pointer 786 * @ret: Pointer to write optional return code 787 * 788 * Returns: true if the VCPU needs to return to a preemptible + interruptible 789 * and skip guest entry. 790 * 791 * This function disambiguates between two different types of exits: exits to a 792 * preemptible + interruptible kernel context and exits to userspace. For an 793 * exit to userspace, this function will write the return code to ret and return 794 * true. For an exit to preemptible + interruptible kernel context (i.e. check 795 * for pending work and re-enter), return true without writing to ret. 796 */ 797 static bool kvm_vcpu_exit_request(struct kvm_vcpu *vcpu, int *ret) 798 { 799 struct kvm_run *run = vcpu->run; 800 801 /* 802 * If we're using a userspace irqchip, then check if we need 803 * to tell a userspace irqchip about timer or PMU level 804 * changes and if so, exit to userspace (the actual level 805 * state gets updated in kvm_timer_update_run and 806 * kvm_pmu_update_run below). 807 */ 808 if (static_branch_unlikely(&userspace_irqchip_in_use)) { 809 if (kvm_timer_should_notify_user(vcpu) || 810 kvm_pmu_should_notify_user(vcpu)) { 811 *ret = -EINTR; 812 run->exit_reason = KVM_EXIT_INTR; 813 return true; 814 } 815 } 816 817 if (unlikely(vcpu_on_unsupported_cpu(vcpu))) { 818 run->exit_reason = KVM_EXIT_FAIL_ENTRY; 819 run->fail_entry.hardware_entry_failure_reason = KVM_EXIT_FAIL_ENTRY_CPU_UNSUPPORTED; 820 run->fail_entry.cpu = smp_processor_id(); 821 *ret = 0; 822 return true; 823 } 824 825 return kvm_request_pending(vcpu) || 826 xfer_to_guest_mode_work_pending(); 827 } 828 829 /* 830 * Actually run the vCPU, entering an RCU extended quiescent state (EQS) while 831 * the vCPU is running. 832 * 833 * This must be noinstr as instrumentation may make use of RCU, and this is not 834 * safe during the EQS. 835 */ 836 static int noinstr kvm_arm_vcpu_enter_exit(struct kvm_vcpu *vcpu) 837 { 838 int ret; 839 840 guest_state_enter_irqoff(); 841 ret = kvm_call_hyp_ret(__kvm_vcpu_run, vcpu); 842 guest_state_exit_irqoff(); 843 844 return ret; 845 } 846 847 /** 848 * kvm_arch_vcpu_ioctl_run - the main VCPU run function to execute guest code 849 * @vcpu: The VCPU pointer 850 * 851 * This function is called through the VCPU_RUN ioctl called from user space. It 852 * will execute VM code in a loop until the time slice for the process is used 853 * or some emulation is needed from user space in which case the function will 854 * return with return value 0 and with the kvm_run structure filled in with the 855 * required data for the requested emulation. 856 */ 857 int kvm_arch_vcpu_ioctl_run(struct kvm_vcpu *vcpu) 858 { 859 struct kvm_run *run = vcpu->run; 860 int ret; 861 862 if (run->exit_reason == KVM_EXIT_MMIO) { 863 ret = kvm_handle_mmio_return(vcpu); 864 if (ret) 865 return ret; 866 } 867 868 vcpu_load(vcpu); 869 870 if (run->immediate_exit) { 871 ret = -EINTR; 872 goto out; 873 } 874 875 kvm_sigset_activate(vcpu); 876 877 ret = 1; 878 run->exit_reason = KVM_EXIT_UNKNOWN; 879 run->flags = 0; 880 while (ret > 0) { 881 /* 882 * Check conditions before entering the guest 883 */ 884 ret = xfer_to_guest_mode_handle_work(vcpu); 885 if (!ret) 886 ret = 1; 887 888 if (ret > 0) 889 ret = check_vcpu_requests(vcpu); 890 891 /* 892 * Preparing the interrupts to be injected also 893 * involves poking the GIC, which must be done in a 894 * non-preemptible context. 895 */ 896 preempt_disable(); 897 898 /* 899 * The VMID allocator only tracks active VMIDs per 900 * physical CPU, and therefore the VMID allocated may not be 901 * preserved on VMID roll-over if the task was preempted, 902 * making a thread's VMID inactive. So we need to call 903 * kvm_arm_vmid_update() in non-premptible context. 904 */ 905 kvm_arm_vmid_update(&vcpu->arch.hw_mmu->vmid); 906 907 kvm_pmu_flush_hwstate(vcpu); 908 909 local_irq_disable(); 910 911 kvm_vgic_flush_hwstate(vcpu); 912 913 kvm_pmu_update_vcpu_events(vcpu); 914 915 /* 916 * Ensure we set mode to IN_GUEST_MODE after we disable 917 * interrupts and before the final VCPU requests check. 918 * See the comment in kvm_vcpu_exiting_guest_mode() and 919 * Documentation/virt/kvm/vcpu-requests.rst 920 */ 921 smp_store_mb(vcpu->mode, IN_GUEST_MODE); 922 923 if (ret <= 0 || kvm_vcpu_exit_request(vcpu, &ret)) { 924 vcpu->mode = OUTSIDE_GUEST_MODE; 925 isb(); /* Ensure work in x_flush_hwstate is committed */ 926 kvm_pmu_sync_hwstate(vcpu); 927 if (static_branch_unlikely(&userspace_irqchip_in_use)) 928 kvm_timer_sync_user(vcpu); 929 kvm_vgic_sync_hwstate(vcpu); 930 local_irq_enable(); 931 preempt_enable(); 932 continue; 933 } 934 935 kvm_arm_setup_debug(vcpu); 936 kvm_arch_vcpu_ctxflush_fp(vcpu); 937 938 /************************************************************** 939 * Enter the guest 940 */ 941 trace_kvm_entry(*vcpu_pc(vcpu)); 942 guest_timing_enter_irqoff(); 943 944 ret = kvm_arm_vcpu_enter_exit(vcpu); 945 946 vcpu->mode = OUTSIDE_GUEST_MODE; 947 vcpu->stat.exits++; 948 /* 949 * Back from guest 950 *************************************************************/ 951 952 kvm_arm_clear_debug(vcpu); 953 954 /* 955 * We must sync the PMU state before the vgic state so 956 * that the vgic can properly sample the updated state of the 957 * interrupt line. 958 */ 959 kvm_pmu_sync_hwstate(vcpu); 960 961 /* 962 * Sync the vgic state before syncing the timer state because 963 * the timer code needs to know if the virtual timer 964 * interrupts are active. 965 */ 966 kvm_vgic_sync_hwstate(vcpu); 967 968 /* 969 * Sync the timer hardware state before enabling interrupts as 970 * we don't want vtimer interrupts to race with syncing the 971 * timer virtual interrupt state. 972 */ 973 if (static_branch_unlikely(&userspace_irqchip_in_use)) 974 kvm_timer_sync_user(vcpu); 975 976 kvm_arch_vcpu_ctxsync_fp(vcpu); 977 978 /* 979 * We must ensure that any pending interrupts are taken before 980 * we exit guest timing so that timer ticks are accounted as 981 * guest time. Transiently unmask interrupts so that any 982 * pending interrupts are taken. 983 * 984 * Per ARM DDI 0487G.b section D1.13.4, an ISB (or other 985 * context synchronization event) is necessary to ensure that 986 * pending interrupts are taken. 987 */ 988 if (ARM_EXCEPTION_CODE(ret) == ARM_EXCEPTION_IRQ) { 989 local_irq_enable(); 990 isb(); 991 local_irq_disable(); 992 } 993 994 guest_timing_exit_irqoff(); 995 996 local_irq_enable(); 997 998 trace_kvm_exit(ret, kvm_vcpu_trap_get_class(vcpu), *vcpu_pc(vcpu)); 999 1000 /* Exit types that need handling before we can be preempted */ 1001 handle_exit_early(vcpu, ret); 1002 1003 preempt_enable(); 1004 1005 /* 1006 * The ARMv8 architecture doesn't give the hypervisor 1007 * a mechanism to prevent a guest from dropping to AArch32 EL0 1008 * if implemented by the CPU. If we spot the guest in such 1009 * state and that we decided it wasn't supposed to do so (like 1010 * with the asymmetric AArch32 case), return to userspace with 1011 * a fatal error. 1012 */ 1013 if (vcpu_mode_is_bad_32bit(vcpu)) { 1014 /* 1015 * As we have caught the guest red-handed, decide that 1016 * it isn't fit for purpose anymore by making the vcpu 1017 * invalid. The VMM can try and fix it by issuing a 1018 * KVM_ARM_VCPU_INIT if it really wants to. 1019 */ 1020 vcpu->arch.target = -1; 1021 ret = ARM_EXCEPTION_IL; 1022 } 1023 1024 ret = handle_exit(vcpu, ret); 1025 } 1026 1027 /* Tell userspace about in-kernel device output levels */ 1028 if (unlikely(!irqchip_in_kernel(vcpu->kvm))) { 1029 kvm_timer_update_run(vcpu); 1030 kvm_pmu_update_run(vcpu); 1031 } 1032 1033 kvm_sigset_deactivate(vcpu); 1034 1035 out: 1036 /* 1037 * In the unlikely event that we are returning to userspace 1038 * with pending exceptions or PC adjustment, commit these 1039 * adjustments in order to give userspace a consistent view of 1040 * the vcpu state. Note that this relies on __kvm_adjust_pc() 1041 * being preempt-safe on VHE. 1042 */ 1043 if (unlikely(vcpu_get_flag(vcpu, PENDING_EXCEPTION) || 1044 vcpu_get_flag(vcpu, INCREMENT_PC))) 1045 kvm_call_hyp(__kvm_adjust_pc, vcpu); 1046 1047 vcpu_put(vcpu); 1048 return ret; 1049 } 1050 1051 static int vcpu_interrupt_line(struct kvm_vcpu *vcpu, int number, bool level) 1052 { 1053 int bit_index; 1054 bool set; 1055 unsigned long *hcr; 1056 1057 if (number == KVM_ARM_IRQ_CPU_IRQ) 1058 bit_index = __ffs(HCR_VI); 1059 else /* KVM_ARM_IRQ_CPU_FIQ */ 1060 bit_index = __ffs(HCR_VF); 1061 1062 hcr = vcpu_hcr(vcpu); 1063 if (level) 1064 set = test_and_set_bit(bit_index, hcr); 1065 else 1066 set = test_and_clear_bit(bit_index, hcr); 1067 1068 /* 1069 * If we didn't change anything, no need to wake up or kick other CPUs 1070 */ 1071 if (set == level) 1072 return 0; 1073 1074 /* 1075 * The vcpu irq_lines field was updated, wake up sleeping VCPUs and 1076 * trigger a world-switch round on the running physical CPU to set the 1077 * virtual IRQ/FIQ fields in the HCR appropriately. 1078 */ 1079 kvm_make_request(KVM_REQ_IRQ_PENDING, vcpu); 1080 kvm_vcpu_kick(vcpu); 1081 1082 return 0; 1083 } 1084 1085 int kvm_vm_ioctl_irq_line(struct kvm *kvm, struct kvm_irq_level *irq_level, 1086 bool line_status) 1087 { 1088 u32 irq = irq_level->irq; 1089 unsigned int irq_type, vcpu_idx, irq_num; 1090 int nrcpus = atomic_read(&kvm->online_vcpus); 1091 struct kvm_vcpu *vcpu = NULL; 1092 bool level = irq_level->level; 1093 1094 irq_type = (irq >> KVM_ARM_IRQ_TYPE_SHIFT) & KVM_ARM_IRQ_TYPE_MASK; 1095 vcpu_idx = (irq >> KVM_ARM_IRQ_VCPU_SHIFT) & KVM_ARM_IRQ_VCPU_MASK; 1096 vcpu_idx += ((irq >> KVM_ARM_IRQ_VCPU2_SHIFT) & KVM_ARM_IRQ_VCPU2_MASK) * (KVM_ARM_IRQ_VCPU_MASK + 1); 1097 irq_num = (irq >> KVM_ARM_IRQ_NUM_SHIFT) & KVM_ARM_IRQ_NUM_MASK; 1098 1099 trace_kvm_irq_line(irq_type, vcpu_idx, irq_num, irq_level->level); 1100 1101 switch (irq_type) { 1102 case KVM_ARM_IRQ_TYPE_CPU: 1103 if (irqchip_in_kernel(kvm)) 1104 return -ENXIO; 1105 1106 if (vcpu_idx >= nrcpus) 1107 return -EINVAL; 1108 1109 vcpu = kvm_get_vcpu(kvm, vcpu_idx); 1110 if (!vcpu) 1111 return -EINVAL; 1112 1113 if (irq_num > KVM_ARM_IRQ_CPU_FIQ) 1114 return -EINVAL; 1115 1116 return vcpu_interrupt_line(vcpu, irq_num, level); 1117 case KVM_ARM_IRQ_TYPE_PPI: 1118 if (!irqchip_in_kernel(kvm)) 1119 return -ENXIO; 1120 1121 if (vcpu_idx >= nrcpus) 1122 return -EINVAL; 1123 1124 vcpu = kvm_get_vcpu(kvm, vcpu_idx); 1125 if (!vcpu) 1126 return -EINVAL; 1127 1128 if (irq_num < VGIC_NR_SGIS || irq_num >= VGIC_NR_PRIVATE_IRQS) 1129 return -EINVAL; 1130 1131 return kvm_vgic_inject_irq(kvm, vcpu->vcpu_id, irq_num, level, NULL); 1132 case KVM_ARM_IRQ_TYPE_SPI: 1133 if (!irqchip_in_kernel(kvm)) 1134 return -ENXIO; 1135 1136 if (irq_num < VGIC_NR_PRIVATE_IRQS) 1137 return -EINVAL; 1138 1139 return kvm_vgic_inject_irq(kvm, 0, irq_num, level, NULL); 1140 } 1141 1142 return -EINVAL; 1143 } 1144 1145 static int kvm_vcpu_set_target(struct kvm_vcpu *vcpu, 1146 const struct kvm_vcpu_init *init) 1147 { 1148 unsigned int i, ret; 1149 u32 phys_target = kvm_target_cpu(); 1150 1151 if (init->target != phys_target) 1152 return -EINVAL; 1153 1154 /* 1155 * Secondary and subsequent calls to KVM_ARM_VCPU_INIT must 1156 * use the same target. 1157 */ 1158 if (vcpu->arch.target != -1 && vcpu->arch.target != init->target) 1159 return -EINVAL; 1160 1161 /* -ENOENT for unknown features, -EINVAL for invalid combinations. */ 1162 for (i = 0; i < sizeof(init->features) * 8; i++) { 1163 bool set = (init->features[i / 32] & (1 << (i % 32))); 1164 1165 if (set && i >= KVM_VCPU_MAX_FEATURES) 1166 return -ENOENT; 1167 1168 /* 1169 * Secondary and subsequent calls to KVM_ARM_VCPU_INIT must 1170 * use the same feature set. 1171 */ 1172 if (vcpu->arch.target != -1 && i < KVM_VCPU_MAX_FEATURES && 1173 test_bit(i, vcpu->arch.features) != set) 1174 return -EINVAL; 1175 1176 if (set) 1177 set_bit(i, vcpu->arch.features); 1178 } 1179 1180 vcpu->arch.target = phys_target; 1181 1182 /* Now we know what it is, we can reset it. */ 1183 ret = kvm_reset_vcpu(vcpu); 1184 if (ret) { 1185 vcpu->arch.target = -1; 1186 bitmap_zero(vcpu->arch.features, KVM_VCPU_MAX_FEATURES); 1187 } 1188 1189 return ret; 1190 } 1191 1192 static int kvm_arch_vcpu_ioctl_vcpu_init(struct kvm_vcpu *vcpu, 1193 struct kvm_vcpu_init *init) 1194 { 1195 int ret; 1196 1197 ret = kvm_vcpu_set_target(vcpu, init); 1198 if (ret) 1199 return ret; 1200 1201 /* 1202 * Ensure a rebooted VM will fault in RAM pages and detect if the 1203 * guest MMU is turned off and flush the caches as needed. 1204 * 1205 * S2FWB enforces all memory accesses to RAM being cacheable, 1206 * ensuring that the data side is always coherent. We still 1207 * need to invalidate the I-cache though, as FWB does *not* 1208 * imply CTR_EL0.DIC. 1209 */ 1210 if (vcpu_has_run_once(vcpu)) { 1211 if (!cpus_have_final_cap(ARM64_HAS_STAGE2_FWB)) 1212 stage2_unmap_vm(vcpu->kvm); 1213 else 1214 icache_inval_all_pou(); 1215 } 1216 1217 vcpu_reset_hcr(vcpu); 1218 vcpu->arch.cptr_el2 = CPTR_EL2_DEFAULT; 1219 1220 /* 1221 * Handle the "start in power-off" case. 1222 */ 1223 if (test_bit(KVM_ARM_VCPU_POWER_OFF, vcpu->arch.features)) 1224 kvm_arm_vcpu_power_off(vcpu); 1225 else 1226 vcpu->arch.mp_state.mp_state = KVM_MP_STATE_RUNNABLE; 1227 1228 return 0; 1229 } 1230 1231 static int kvm_arm_vcpu_set_attr(struct kvm_vcpu *vcpu, 1232 struct kvm_device_attr *attr) 1233 { 1234 int ret = -ENXIO; 1235 1236 switch (attr->group) { 1237 default: 1238 ret = kvm_arm_vcpu_arch_set_attr(vcpu, attr); 1239 break; 1240 } 1241 1242 return ret; 1243 } 1244 1245 static int kvm_arm_vcpu_get_attr(struct kvm_vcpu *vcpu, 1246 struct kvm_device_attr *attr) 1247 { 1248 int ret = -ENXIO; 1249 1250 switch (attr->group) { 1251 default: 1252 ret = kvm_arm_vcpu_arch_get_attr(vcpu, attr); 1253 break; 1254 } 1255 1256 return ret; 1257 } 1258 1259 static int kvm_arm_vcpu_has_attr(struct kvm_vcpu *vcpu, 1260 struct kvm_device_attr *attr) 1261 { 1262 int ret = -ENXIO; 1263 1264 switch (attr->group) { 1265 default: 1266 ret = kvm_arm_vcpu_arch_has_attr(vcpu, attr); 1267 break; 1268 } 1269 1270 return ret; 1271 } 1272 1273 static int kvm_arm_vcpu_get_events(struct kvm_vcpu *vcpu, 1274 struct kvm_vcpu_events *events) 1275 { 1276 memset(events, 0, sizeof(*events)); 1277 1278 return __kvm_arm_vcpu_get_events(vcpu, events); 1279 } 1280 1281 static int kvm_arm_vcpu_set_events(struct kvm_vcpu *vcpu, 1282 struct kvm_vcpu_events *events) 1283 { 1284 int i; 1285 1286 /* check whether the reserved field is zero */ 1287 for (i = 0; i < ARRAY_SIZE(events->reserved); i++) 1288 if (events->reserved[i]) 1289 return -EINVAL; 1290 1291 /* check whether the pad field is zero */ 1292 for (i = 0; i < ARRAY_SIZE(events->exception.pad); i++) 1293 if (events->exception.pad[i]) 1294 return -EINVAL; 1295 1296 return __kvm_arm_vcpu_set_events(vcpu, events); 1297 } 1298 1299 long kvm_arch_vcpu_ioctl(struct file *filp, 1300 unsigned int ioctl, unsigned long arg) 1301 { 1302 struct kvm_vcpu *vcpu = filp->private_data; 1303 void __user *argp = (void __user *)arg; 1304 struct kvm_device_attr attr; 1305 long r; 1306 1307 switch (ioctl) { 1308 case KVM_ARM_VCPU_INIT: { 1309 struct kvm_vcpu_init init; 1310 1311 r = -EFAULT; 1312 if (copy_from_user(&init, argp, sizeof(init))) 1313 break; 1314 1315 r = kvm_arch_vcpu_ioctl_vcpu_init(vcpu, &init); 1316 break; 1317 } 1318 case KVM_SET_ONE_REG: 1319 case KVM_GET_ONE_REG: { 1320 struct kvm_one_reg reg; 1321 1322 r = -ENOEXEC; 1323 if (unlikely(!kvm_vcpu_initialized(vcpu))) 1324 break; 1325 1326 r = -EFAULT; 1327 if (copy_from_user(®, argp, sizeof(reg))) 1328 break; 1329 1330 /* 1331 * We could owe a reset due to PSCI. Handle the pending reset 1332 * here to ensure userspace register accesses are ordered after 1333 * the reset. 1334 */ 1335 if (kvm_check_request(KVM_REQ_VCPU_RESET, vcpu)) 1336 kvm_reset_vcpu(vcpu); 1337 1338 if (ioctl == KVM_SET_ONE_REG) 1339 r = kvm_arm_set_reg(vcpu, ®); 1340 else 1341 r = kvm_arm_get_reg(vcpu, ®); 1342 break; 1343 } 1344 case KVM_GET_REG_LIST: { 1345 struct kvm_reg_list __user *user_list = argp; 1346 struct kvm_reg_list reg_list; 1347 unsigned n; 1348 1349 r = -ENOEXEC; 1350 if (unlikely(!kvm_vcpu_initialized(vcpu))) 1351 break; 1352 1353 r = -EPERM; 1354 if (!kvm_arm_vcpu_is_finalized(vcpu)) 1355 break; 1356 1357 r = -EFAULT; 1358 if (copy_from_user(®_list, user_list, sizeof(reg_list))) 1359 break; 1360 n = reg_list.n; 1361 reg_list.n = kvm_arm_num_regs(vcpu); 1362 if (copy_to_user(user_list, ®_list, sizeof(reg_list))) 1363 break; 1364 r = -E2BIG; 1365 if (n < reg_list.n) 1366 break; 1367 r = kvm_arm_copy_reg_indices(vcpu, user_list->reg); 1368 break; 1369 } 1370 case KVM_SET_DEVICE_ATTR: { 1371 r = -EFAULT; 1372 if (copy_from_user(&attr, argp, sizeof(attr))) 1373 break; 1374 r = kvm_arm_vcpu_set_attr(vcpu, &attr); 1375 break; 1376 } 1377 case KVM_GET_DEVICE_ATTR: { 1378 r = -EFAULT; 1379 if (copy_from_user(&attr, argp, sizeof(attr))) 1380 break; 1381 r = kvm_arm_vcpu_get_attr(vcpu, &attr); 1382 break; 1383 } 1384 case KVM_HAS_DEVICE_ATTR: { 1385 r = -EFAULT; 1386 if (copy_from_user(&attr, argp, sizeof(attr))) 1387 break; 1388 r = kvm_arm_vcpu_has_attr(vcpu, &attr); 1389 break; 1390 } 1391 case KVM_GET_VCPU_EVENTS: { 1392 struct kvm_vcpu_events events; 1393 1394 if (kvm_arm_vcpu_get_events(vcpu, &events)) 1395 return -EINVAL; 1396 1397 if (copy_to_user(argp, &events, sizeof(events))) 1398 return -EFAULT; 1399 1400 return 0; 1401 } 1402 case KVM_SET_VCPU_EVENTS: { 1403 struct kvm_vcpu_events events; 1404 1405 if (copy_from_user(&events, argp, sizeof(events))) 1406 return -EFAULT; 1407 1408 return kvm_arm_vcpu_set_events(vcpu, &events); 1409 } 1410 case KVM_ARM_VCPU_FINALIZE: { 1411 int what; 1412 1413 if (!kvm_vcpu_initialized(vcpu)) 1414 return -ENOEXEC; 1415 1416 if (get_user(what, (const int __user *)argp)) 1417 return -EFAULT; 1418 1419 return kvm_arm_vcpu_finalize(vcpu, what); 1420 } 1421 default: 1422 r = -EINVAL; 1423 } 1424 1425 return r; 1426 } 1427 1428 void kvm_arch_sync_dirty_log(struct kvm *kvm, struct kvm_memory_slot *memslot) 1429 { 1430 1431 } 1432 1433 void kvm_arch_flush_remote_tlbs_memslot(struct kvm *kvm, 1434 const struct kvm_memory_slot *memslot) 1435 { 1436 kvm_flush_remote_tlbs(kvm); 1437 } 1438 1439 static int kvm_vm_ioctl_set_device_addr(struct kvm *kvm, 1440 struct kvm_arm_device_addr *dev_addr) 1441 { 1442 switch (FIELD_GET(KVM_ARM_DEVICE_ID_MASK, dev_addr->id)) { 1443 case KVM_ARM_DEVICE_VGIC_V2: 1444 if (!vgic_present) 1445 return -ENXIO; 1446 return kvm_set_legacy_vgic_v2_addr(kvm, dev_addr); 1447 default: 1448 return -ENODEV; 1449 } 1450 } 1451 1452 long kvm_arch_vm_ioctl(struct file *filp, 1453 unsigned int ioctl, unsigned long arg) 1454 { 1455 struct kvm *kvm = filp->private_data; 1456 void __user *argp = (void __user *)arg; 1457 1458 switch (ioctl) { 1459 case KVM_CREATE_IRQCHIP: { 1460 int ret; 1461 if (!vgic_present) 1462 return -ENXIO; 1463 mutex_lock(&kvm->lock); 1464 ret = kvm_vgic_create(kvm, KVM_DEV_TYPE_ARM_VGIC_V2); 1465 mutex_unlock(&kvm->lock); 1466 return ret; 1467 } 1468 case KVM_ARM_SET_DEVICE_ADDR: { 1469 struct kvm_arm_device_addr dev_addr; 1470 1471 if (copy_from_user(&dev_addr, argp, sizeof(dev_addr))) 1472 return -EFAULT; 1473 return kvm_vm_ioctl_set_device_addr(kvm, &dev_addr); 1474 } 1475 case KVM_ARM_PREFERRED_TARGET: { 1476 struct kvm_vcpu_init init; 1477 1478 kvm_vcpu_preferred_target(&init); 1479 1480 if (copy_to_user(argp, &init, sizeof(init))) 1481 return -EFAULT; 1482 1483 return 0; 1484 } 1485 case KVM_ARM_MTE_COPY_TAGS: { 1486 struct kvm_arm_copy_mte_tags copy_tags; 1487 1488 if (copy_from_user(©_tags, argp, sizeof(copy_tags))) 1489 return -EFAULT; 1490 return kvm_vm_ioctl_mte_copy_tags(kvm, ©_tags); 1491 } 1492 default: 1493 return -EINVAL; 1494 } 1495 } 1496 1497 static unsigned long nvhe_percpu_size(void) 1498 { 1499 return (unsigned long)CHOOSE_NVHE_SYM(__per_cpu_end) - 1500 (unsigned long)CHOOSE_NVHE_SYM(__per_cpu_start); 1501 } 1502 1503 static unsigned long nvhe_percpu_order(void) 1504 { 1505 unsigned long size = nvhe_percpu_size(); 1506 1507 return size ? get_order(size) : 0; 1508 } 1509 1510 /* A lookup table holding the hypervisor VA for each vector slot */ 1511 static void *hyp_spectre_vector_selector[BP_HARDEN_EL2_SLOTS]; 1512 1513 static void kvm_init_vector_slot(void *base, enum arm64_hyp_spectre_vector slot) 1514 { 1515 hyp_spectre_vector_selector[slot] = __kvm_vector_slot2addr(base, slot); 1516 } 1517 1518 static int kvm_init_vector_slots(void) 1519 { 1520 int err; 1521 void *base; 1522 1523 base = kern_hyp_va(kvm_ksym_ref(__kvm_hyp_vector)); 1524 kvm_init_vector_slot(base, HYP_VECTOR_DIRECT); 1525 1526 base = kern_hyp_va(kvm_ksym_ref(__bp_harden_hyp_vecs)); 1527 kvm_init_vector_slot(base, HYP_VECTOR_SPECTRE_DIRECT); 1528 1529 if (kvm_system_needs_idmapped_vectors() && 1530 !is_protected_kvm_enabled()) { 1531 err = create_hyp_exec_mappings(__pa_symbol(__bp_harden_hyp_vecs), 1532 __BP_HARDEN_HYP_VECS_SZ, &base); 1533 if (err) 1534 return err; 1535 } 1536 1537 kvm_init_vector_slot(base, HYP_VECTOR_INDIRECT); 1538 kvm_init_vector_slot(base, HYP_VECTOR_SPECTRE_INDIRECT); 1539 return 0; 1540 } 1541 1542 static void cpu_prepare_hyp_mode(int cpu, u32 hyp_va_bits) 1543 { 1544 struct kvm_nvhe_init_params *params = per_cpu_ptr_nvhe_sym(kvm_init_params, cpu); 1545 unsigned long tcr; 1546 1547 /* 1548 * Calculate the raw per-cpu offset without a translation from the 1549 * kernel's mapping to the linear mapping, and store it in tpidr_el2 1550 * so that we can use adr_l to access per-cpu variables in EL2. 1551 * Also drop the KASAN tag which gets in the way... 1552 */ 1553 params->tpidr_el2 = (unsigned long)kasan_reset_tag(per_cpu_ptr_nvhe_sym(__per_cpu_start, cpu)) - 1554 (unsigned long)kvm_ksym_ref(CHOOSE_NVHE_SYM(__per_cpu_start)); 1555 1556 params->mair_el2 = read_sysreg(mair_el1); 1557 1558 tcr = (read_sysreg(tcr_el1) & TCR_EL2_MASK) | TCR_EL2_RES1; 1559 tcr &= ~TCR_T0SZ_MASK; 1560 tcr |= TCR_T0SZ(hyp_va_bits); 1561 params->tcr_el2 = tcr; 1562 1563 params->pgd_pa = kvm_mmu_get_httbr(); 1564 if (is_protected_kvm_enabled()) 1565 params->hcr_el2 = HCR_HOST_NVHE_PROTECTED_FLAGS; 1566 else 1567 params->hcr_el2 = HCR_HOST_NVHE_FLAGS; 1568 params->vttbr = params->vtcr = 0; 1569 1570 /* 1571 * Flush the init params from the data cache because the struct will 1572 * be read while the MMU is off. 1573 */ 1574 kvm_flush_dcache_to_poc(params, sizeof(*params)); 1575 } 1576 1577 static void hyp_install_host_vector(void) 1578 { 1579 struct kvm_nvhe_init_params *params; 1580 struct arm_smccc_res res; 1581 1582 /* Switch from the HYP stub to our own HYP init vector */ 1583 __hyp_set_vectors(kvm_get_idmap_vector()); 1584 1585 /* 1586 * Call initialization code, and switch to the full blown HYP code. 1587 * If the cpucaps haven't been finalized yet, something has gone very 1588 * wrong, and hyp will crash and burn when it uses any 1589 * cpus_have_const_cap() wrapper. 1590 */ 1591 BUG_ON(!system_capabilities_finalized()); 1592 params = this_cpu_ptr_nvhe_sym(kvm_init_params); 1593 arm_smccc_1_1_hvc(KVM_HOST_SMCCC_FUNC(__kvm_hyp_init), virt_to_phys(params), &res); 1594 WARN_ON(res.a0 != SMCCC_RET_SUCCESS); 1595 } 1596 1597 static void cpu_init_hyp_mode(void) 1598 { 1599 hyp_install_host_vector(); 1600 1601 /* 1602 * Disabling SSBD on a non-VHE system requires us to enable SSBS 1603 * at EL2. 1604 */ 1605 if (this_cpu_has_cap(ARM64_SSBS) && 1606 arm64_get_spectre_v4_state() == SPECTRE_VULNERABLE) { 1607 kvm_call_hyp_nvhe(__kvm_enable_ssbs); 1608 } 1609 } 1610 1611 static void cpu_hyp_reset(void) 1612 { 1613 if (!is_kernel_in_hyp_mode()) 1614 __hyp_reset_vectors(); 1615 } 1616 1617 /* 1618 * EL2 vectors can be mapped and rerouted in a number of ways, 1619 * depending on the kernel configuration and CPU present: 1620 * 1621 * - If the CPU is affected by Spectre-v2, the hardening sequence is 1622 * placed in one of the vector slots, which is executed before jumping 1623 * to the real vectors. 1624 * 1625 * - If the CPU also has the ARM64_SPECTRE_V3A cap, the slot 1626 * containing the hardening sequence is mapped next to the idmap page, 1627 * and executed before jumping to the real vectors. 1628 * 1629 * - If the CPU only has the ARM64_SPECTRE_V3A cap, then an 1630 * empty slot is selected, mapped next to the idmap page, and 1631 * executed before jumping to the real vectors. 1632 * 1633 * Note that ARM64_SPECTRE_V3A is somewhat incompatible with 1634 * VHE, as we don't have hypervisor-specific mappings. If the system 1635 * is VHE and yet selects this capability, it will be ignored. 1636 */ 1637 static void cpu_set_hyp_vector(void) 1638 { 1639 struct bp_hardening_data *data = this_cpu_ptr(&bp_hardening_data); 1640 void *vector = hyp_spectre_vector_selector[data->slot]; 1641 1642 if (!is_protected_kvm_enabled()) 1643 *this_cpu_ptr_hyp_sym(kvm_hyp_vector) = (unsigned long)vector; 1644 else 1645 kvm_call_hyp_nvhe(__pkvm_cpu_set_vector, data->slot); 1646 } 1647 1648 static void cpu_hyp_init_context(void) 1649 { 1650 kvm_init_host_cpu_context(&this_cpu_ptr_hyp_sym(kvm_host_data)->host_ctxt); 1651 1652 if (!is_kernel_in_hyp_mode()) 1653 cpu_init_hyp_mode(); 1654 } 1655 1656 static void cpu_hyp_init_features(void) 1657 { 1658 cpu_set_hyp_vector(); 1659 kvm_arm_init_debug(); 1660 1661 if (is_kernel_in_hyp_mode()) 1662 kvm_timer_init_vhe(); 1663 1664 if (vgic_present) 1665 kvm_vgic_init_cpu_hardware(); 1666 } 1667 1668 static void cpu_hyp_reinit(void) 1669 { 1670 cpu_hyp_reset(); 1671 cpu_hyp_init_context(); 1672 cpu_hyp_init_features(); 1673 } 1674 1675 static void _kvm_arch_hardware_enable(void *discard) 1676 { 1677 if (!__this_cpu_read(kvm_arm_hardware_enabled)) { 1678 cpu_hyp_reinit(); 1679 __this_cpu_write(kvm_arm_hardware_enabled, 1); 1680 } 1681 } 1682 1683 int kvm_arch_hardware_enable(void) 1684 { 1685 _kvm_arch_hardware_enable(NULL); 1686 return 0; 1687 } 1688 1689 static void _kvm_arch_hardware_disable(void *discard) 1690 { 1691 if (__this_cpu_read(kvm_arm_hardware_enabled)) { 1692 cpu_hyp_reset(); 1693 __this_cpu_write(kvm_arm_hardware_enabled, 0); 1694 } 1695 } 1696 1697 void kvm_arch_hardware_disable(void) 1698 { 1699 if (!is_protected_kvm_enabled()) 1700 _kvm_arch_hardware_disable(NULL); 1701 } 1702 1703 #ifdef CONFIG_CPU_PM 1704 static int hyp_init_cpu_pm_notifier(struct notifier_block *self, 1705 unsigned long cmd, 1706 void *v) 1707 { 1708 /* 1709 * kvm_arm_hardware_enabled is left with its old value over 1710 * PM_ENTER->PM_EXIT. It is used to indicate PM_EXIT should 1711 * re-enable hyp. 1712 */ 1713 switch (cmd) { 1714 case CPU_PM_ENTER: 1715 if (__this_cpu_read(kvm_arm_hardware_enabled)) 1716 /* 1717 * don't update kvm_arm_hardware_enabled here 1718 * so that the hardware will be re-enabled 1719 * when we resume. See below. 1720 */ 1721 cpu_hyp_reset(); 1722 1723 return NOTIFY_OK; 1724 case CPU_PM_ENTER_FAILED: 1725 case CPU_PM_EXIT: 1726 if (__this_cpu_read(kvm_arm_hardware_enabled)) 1727 /* The hardware was enabled before suspend. */ 1728 cpu_hyp_reinit(); 1729 1730 return NOTIFY_OK; 1731 1732 default: 1733 return NOTIFY_DONE; 1734 } 1735 } 1736 1737 static struct notifier_block hyp_init_cpu_pm_nb = { 1738 .notifier_call = hyp_init_cpu_pm_notifier, 1739 }; 1740 1741 static void hyp_cpu_pm_init(void) 1742 { 1743 if (!is_protected_kvm_enabled()) 1744 cpu_pm_register_notifier(&hyp_init_cpu_pm_nb); 1745 } 1746 static void hyp_cpu_pm_exit(void) 1747 { 1748 if (!is_protected_kvm_enabled()) 1749 cpu_pm_unregister_notifier(&hyp_init_cpu_pm_nb); 1750 } 1751 #else 1752 static inline void hyp_cpu_pm_init(void) 1753 { 1754 } 1755 static inline void hyp_cpu_pm_exit(void) 1756 { 1757 } 1758 #endif 1759 1760 static void init_cpu_logical_map(void) 1761 { 1762 unsigned int cpu; 1763 1764 /* 1765 * Copy the MPIDR <-> logical CPU ID mapping to hyp. 1766 * Only copy the set of online CPUs whose features have been checked 1767 * against the finalized system capabilities. The hypervisor will not 1768 * allow any other CPUs from the `possible` set to boot. 1769 */ 1770 for_each_online_cpu(cpu) 1771 hyp_cpu_logical_map[cpu] = cpu_logical_map(cpu); 1772 } 1773 1774 #define init_psci_0_1_impl_state(config, what) \ 1775 config.psci_0_1_ ## what ## _implemented = psci_ops.what 1776 1777 static bool init_psci_relay(void) 1778 { 1779 /* 1780 * If PSCI has not been initialized, protected KVM cannot install 1781 * itself on newly booted CPUs. 1782 */ 1783 if (!psci_ops.get_version) { 1784 kvm_err("Cannot initialize protected mode without PSCI\n"); 1785 return false; 1786 } 1787 1788 kvm_host_psci_config.version = psci_ops.get_version(); 1789 1790 if (kvm_host_psci_config.version == PSCI_VERSION(0, 1)) { 1791 kvm_host_psci_config.function_ids_0_1 = get_psci_0_1_function_ids(); 1792 init_psci_0_1_impl_state(kvm_host_psci_config, cpu_suspend); 1793 init_psci_0_1_impl_state(kvm_host_psci_config, cpu_on); 1794 init_psci_0_1_impl_state(kvm_host_psci_config, cpu_off); 1795 init_psci_0_1_impl_state(kvm_host_psci_config, migrate); 1796 } 1797 return true; 1798 } 1799 1800 static int init_subsystems(void) 1801 { 1802 int err = 0; 1803 1804 /* 1805 * Enable hardware so that subsystem initialisation can access EL2. 1806 */ 1807 on_each_cpu(_kvm_arch_hardware_enable, NULL, 1); 1808 1809 /* 1810 * Register CPU lower-power notifier 1811 */ 1812 hyp_cpu_pm_init(); 1813 1814 /* 1815 * Init HYP view of VGIC 1816 */ 1817 err = kvm_vgic_hyp_init(); 1818 switch (err) { 1819 case 0: 1820 vgic_present = true; 1821 break; 1822 case -ENODEV: 1823 case -ENXIO: 1824 vgic_present = false; 1825 err = 0; 1826 break; 1827 default: 1828 goto out; 1829 } 1830 1831 /* 1832 * Init HYP architected timer support 1833 */ 1834 err = kvm_timer_hyp_init(vgic_present); 1835 if (err) 1836 goto out; 1837 1838 kvm_register_perf_callbacks(NULL); 1839 1840 out: 1841 if (err || !is_protected_kvm_enabled()) 1842 on_each_cpu(_kvm_arch_hardware_disable, NULL, 1); 1843 1844 return err; 1845 } 1846 1847 static void teardown_hyp_mode(void) 1848 { 1849 int cpu; 1850 1851 free_hyp_pgds(); 1852 for_each_possible_cpu(cpu) { 1853 free_page(per_cpu(kvm_arm_hyp_stack_page, cpu)); 1854 free_pages(kvm_nvhe_sym(kvm_arm_hyp_percpu_base)[cpu], nvhe_percpu_order()); 1855 } 1856 } 1857 1858 static int do_pkvm_init(u32 hyp_va_bits) 1859 { 1860 void *per_cpu_base = kvm_ksym_ref(kvm_nvhe_sym(kvm_arm_hyp_percpu_base)); 1861 int ret; 1862 1863 preempt_disable(); 1864 cpu_hyp_init_context(); 1865 ret = kvm_call_hyp_nvhe(__pkvm_init, hyp_mem_base, hyp_mem_size, 1866 num_possible_cpus(), kern_hyp_va(per_cpu_base), 1867 hyp_va_bits); 1868 cpu_hyp_init_features(); 1869 1870 /* 1871 * The stub hypercalls are now disabled, so set our local flag to 1872 * prevent a later re-init attempt in kvm_arch_hardware_enable(). 1873 */ 1874 __this_cpu_write(kvm_arm_hardware_enabled, 1); 1875 preempt_enable(); 1876 1877 return ret; 1878 } 1879 1880 static void kvm_hyp_init_symbols(void) 1881 { 1882 kvm_nvhe_sym(id_aa64pfr0_el1_sys_val) = read_sanitised_ftr_reg(SYS_ID_AA64PFR0_EL1); 1883 kvm_nvhe_sym(id_aa64pfr1_el1_sys_val) = read_sanitised_ftr_reg(SYS_ID_AA64PFR1_EL1); 1884 kvm_nvhe_sym(id_aa64isar0_el1_sys_val) = read_sanitised_ftr_reg(SYS_ID_AA64ISAR0_EL1); 1885 kvm_nvhe_sym(id_aa64isar1_el1_sys_val) = read_sanitised_ftr_reg(SYS_ID_AA64ISAR1_EL1); 1886 kvm_nvhe_sym(id_aa64isar2_el1_sys_val) = read_sanitised_ftr_reg(SYS_ID_AA64ISAR2_EL1); 1887 kvm_nvhe_sym(id_aa64mmfr0_el1_sys_val) = read_sanitised_ftr_reg(SYS_ID_AA64MMFR0_EL1); 1888 kvm_nvhe_sym(id_aa64mmfr1_el1_sys_val) = read_sanitised_ftr_reg(SYS_ID_AA64MMFR1_EL1); 1889 kvm_nvhe_sym(id_aa64mmfr2_el1_sys_val) = read_sanitised_ftr_reg(SYS_ID_AA64MMFR2_EL1); 1890 kvm_nvhe_sym(__icache_flags) = __icache_flags; 1891 kvm_nvhe_sym(kvm_arm_vmid_bits) = kvm_arm_vmid_bits; 1892 } 1893 1894 static int kvm_hyp_init_protection(u32 hyp_va_bits) 1895 { 1896 void *addr = phys_to_virt(hyp_mem_base); 1897 int ret; 1898 1899 ret = create_hyp_mappings(addr, addr + hyp_mem_size, PAGE_HYP); 1900 if (ret) 1901 return ret; 1902 1903 ret = do_pkvm_init(hyp_va_bits); 1904 if (ret) 1905 return ret; 1906 1907 free_hyp_pgds(); 1908 1909 return 0; 1910 } 1911 1912 /** 1913 * Inits Hyp-mode on all online CPUs 1914 */ 1915 static int init_hyp_mode(void) 1916 { 1917 u32 hyp_va_bits; 1918 int cpu; 1919 int err = -ENOMEM; 1920 1921 /* 1922 * The protected Hyp-mode cannot be initialized if the memory pool 1923 * allocation has failed. 1924 */ 1925 if (is_protected_kvm_enabled() && !hyp_mem_base) 1926 goto out_err; 1927 1928 /* 1929 * Allocate Hyp PGD and setup Hyp identity mapping 1930 */ 1931 err = kvm_mmu_init(&hyp_va_bits); 1932 if (err) 1933 goto out_err; 1934 1935 /* 1936 * Allocate stack pages for Hypervisor-mode 1937 */ 1938 for_each_possible_cpu(cpu) { 1939 unsigned long stack_page; 1940 1941 stack_page = __get_free_page(GFP_KERNEL); 1942 if (!stack_page) { 1943 err = -ENOMEM; 1944 goto out_err; 1945 } 1946 1947 per_cpu(kvm_arm_hyp_stack_page, cpu) = stack_page; 1948 } 1949 1950 /* 1951 * Allocate and initialize pages for Hypervisor-mode percpu regions. 1952 */ 1953 for_each_possible_cpu(cpu) { 1954 struct page *page; 1955 void *page_addr; 1956 1957 page = alloc_pages(GFP_KERNEL, nvhe_percpu_order()); 1958 if (!page) { 1959 err = -ENOMEM; 1960 goto out_err; 1961 } 1962 1963 page_addr = page_address(page); 1964 memcpy(page_addr, CHOOSE_NVHE_SYM(__per_cpu_start), nvhe_percpu_size()); 1965 kvm_nvhe_sym(kvm_arm_hyp_percpu_base)[cpu] = (unsigned long)page_addr; 1966 } 1967 1968 /* 1969 * Map the Hyp-code called directly from the host 1970 */ 1971 err = create_hyp_mappings(kvm_ksym_ref(__hyp_text_start), 1972 kvm_ksym_ref(__hyp_text_end), PAGE_HYP_EXEC); 1973 if (err) { 1974 kvm_err("Cannot map world-switch code\n"); 1975 goto out_err; 1976 } 1977 1978 err = create_hyp_mappings(kvm_ksym_ref(__hyp_rodata_start), 1979 kvm_ksym_ref(__hyp_rodata_end), PAGE_HYP_RO); 1980 if (err) { 1981 kvm_err("Cannot map .hyp.rodata section\n"); 1982 goto out_err; 1983 } 1984 1985 err = create_hyp_mappings(kvm_ksym_ref(__start_rodata), 1986 kvm_ksym_ref(__end_rodata), PAGE_HYP_RO); 1987 if (err) { 1988 kvm_err("Cannot map rodata section\n"); 1989 goto out_err; 1990 } 1991 1992 /* 1993 * .hyp.bss is guaranteed to be placed at the beginning of the .bss 1994 * section thanks to an assertion in the linker script. Map it RW and 1995 * the rest of .bss RO. 1996 */ 1997 err = create_hyp_mappings(kvm_ksym_ref(__hyp_bss_start), 1998 kvm_ksym_ref(__hyp_bss_end), PAGE_HYP); 1999 if (err) { 2000 kvm_err("Cannot map hyp bss section: %d\n", err); 2001 goto out_err; 2002 } 2003 2004 err = create_hyp_mappings(kvm_ksym_ref(__hyp_bss_end), 2005 kvm_ksym_ref(__bss_stop), PAGE_HYP_RO); 2006 if (err) { 2007 kvm_err("Cannot map bss section\n"); 2008 goto out_err; 2009 } 2010 2011 /* 2012 * Map the Hyp stack pages 2013 */ 2014 for_each_possible_cpu(cpu) { 2015 struct kvm_nvhe_init_params *params = per_cpu_ptr_nvhe_sym(kvm_init_params, cpu); 2016 char *stack_page = (char *)per_cpu(kvm_arm_hyp_stack_page, cpu); 2017 unsigned long hyp_addr; 2018 2019 /* 2020 * Allocate a contiguous HYP private VA range for the stack 2021 * and guard page. The allocation is also aligned based on 2022 * the order of its size. 2023 */ 2024 err = hyp_alloc_private_va_range(PAGE_SIZE * 2, &hyp_addr); 2025 if (err) { 2026 kvm_err("Cannot allocate hyp stack guard page\n"); 2027 goto out_err; 2028 } 2029 2030 /* 2031 * Since the stack grows downwards, map the stack to the page 2032 * at the higher address and leave the lower guard page 2033 * unbacked. 2034 * 2035 * Any valid stack address now has the PAGE_SHIFT bit as 1 2036 * and addresses corresponding to the guard page have the 2037 * PAGE_SHIFT bit as 0 - this is used for overflow detection. 2038 */ 2039 err = __create_hyp_mappings(hyp_addr + PAGE_SIZE, PAGE_SIZE, 2040 __pa(stack_page), PAGE_HYP); 2041 if (err) { 2042 kvm_err("Cannot map hyp stack\n"); 2043 goto out_err; 2044 } 2045 2046 /* 2047 * Save the stack PA in nvhe_init_params. This will be needed 2048 * to recreate the stack mapping in protected nVHE mode. 2049 * __hyp_pa() won't do the right thing there, since the stack 2050 * has been mapped in the flexible private VA space. 2051 */ 2052 params->stack_pa = __pa(stack_page); 2053 2054 params->stack_hyp_va = hyp_addr + (2 * PAGE_SIZE); 2055 } 2056 2057 for_each_possible_cpu(cpu) { 2058 char *percpu_begin = (char *)kvm_nvhe_sym(kvm_arm_hyp_percpu_base)[cpu]; 2059 char *percpu_end = percpu_begin + nvhe_percpu_size(); 2060 2061 /* Map Hyp percpu pages */ 2062 err = create_hyp_mappings(percpu_begin, percpu_end, PAGE_HYP); 2063 if (err) { 2064 kvm_err("Cannot map hyp percpu region\n"); 2065 goto out_err; 2066 } 2067 2068 /* Prepare the CPU initialization parameters */ 2069 cpu_prepare_hyp_mode(cpu, hyp_va_bits); 2070 } 2071 2072 kvm_hyp_init_symbols(); 2073 2074 if (is_protected_kvm_enabled()) { 2075 init_cpu_logical_map(); 2076 2077 if (!init_psci_relay()) { 2078 err = -ENODEV; 2079 goto out_err; 2080 } 2081 2082 err = kvm_hyp_init_protection(hyp_va_bits); 2083 if (err) { 2084 kvm_err("Failed to init hyp memory protection\n"); 2085 goto out_err; 2086 } 2087 } 2088 2089 return 0; 2090 2091 out_err: 2092 teardown_hyp_mode(); 2093 kvm_err("error initializing Hyp mode: %d\n", err); 2094 return err; 2095 } 2096 2097 static void _kvm_host_prot_finalize(void *arg) 2098 { 2099 int *err = arg; 2100 2101 if (WARN_ON(kvm_call_hyp_nvhe(__pkvm_prot_finalize))) 2102 WRITE_ONCE(*err, -EINVAL); 2103 } 2104 2105 static int pkvm_drop_host_privileges(void) 2106 { 2107 int ret = 0; 2108 2109 /* 2110 * Flip the static key upfront as that may no longer be possible 2111 * once the host stage 2 is installed. 2112 */ 2113 static_branch_enable(&kvm_protected_mode_initialized); 2114 on_each_cpu(_kvm_host_prot_finalize, &ret, 1); 2115 return ret; 2116 } 2117 2118 static int finalize_hyp_mode(void) 2119 { 2120 if (!is_protected_kvm_enabled()) 2121 return 0; 2122 2123 /* 2124 * Exclude HYP sections from kmemleak so that they don't get peeked 2125 * at, which would end badly once inaccessible. 2126 */ 2127 kmemleak_free_part(__hyp_bss_start, __hyp_bss_end - __hyp_bss_start); 2128 kmemleak_free_part_phys(hyp_mem_base, hyp_mem_size); 2129 return pkvm_drop_host_privileges(); 2130 } 2131 2132 struct kvm_vcpu *kvm_mpidr_to_vcpu(struct kvm *kvm, unsigned long mpidr) 2133 { 2134 struct kvm_vcpu *vcpu; 2135 unsigned long i; 2136 2137 mpidr &= MPIDR_HWID_BITMASK; 2138 kvm_for_each_vcpu(i, vcpu, kvm) { 2139 if (mpidr == kvm_vcpu_get_mpidr_aff(vcpu)) 2140 return vcpu; 2141 } 2142 return NULL; 2143 } 2144 2145 bool kvm_arch_irqchip_in_kernel(struct kvm *kvm) 2146 { 2147 return irqchip_in_kernel(kvm); 2148 } 2149 2150 bool kvm_arch_has_irq_bypass(void) 2151 { 2152 return true; 2153 } 2154 2155 int kvm_arch_irq_bypass_add_producer(struct irq_bypass_consumer *cons, 2156 struct irq_bypass_producer *prod) 2157 { 2158 struct kvm_kernel_irqfd *irqfd = 2159 container_of(cons, struct kvm_kernel_irqfd, consumer); 2160 2161 return kvm_vgic_v4_set_forwarding(irqfd->kvm, prod->irq, 2162 &irqfd->irq_entry); 2163 } 2164 void kvm_arch_irq_bypass_del_producer(struct irq_bypass_consumer *cons, 2165 struct irq_bypass_producer *prod) 2166 { 2167 struct kvm_kernel_irqfd *irqfd = 2168 container_of(cons, struct kvm_kernel_irqfd, consumer); 2169 2170 kvm_vgic_v4_unset_forwarding(irqfd->kvm, prod->irq, 2171 &irqfd->irq_entry); 2172 } 2173 2174 void kvm_arch_irq_bypass_stop(struct irq_bypass_consumer *cons) 2175 { 2176 struct kvm_kernel_irqfd *irqfd = 2177 container_of(cons, struct kvm_kernel_irqfd, consumer); 2178 2179 kvm_arm_halt_guest(irqfd->kvm); 2180 } 2181 2182 void kvm_arch_irq_bypass_start(struct irq_bypass_consumer *cons) 2183 { 2184 struct kvm_kernel_irqfd *irqfd = 2185 container_of(cons, struct kvm_kernel_irqfd, consumer); 2186 2187 kvm_arm_resume_guest(irqfd->kvm); 2188 } 2189 2190 /** 2191 * Initialize Hyp-mode and memory mappings on all CPUs. 2192 */ 2193 int kvm_arch_init(void *opaque) 2194 { 2195 int err; 2196 bool in_hyp_mode; 2197 2198 if (!is_hyp_mode_available()) { 2199 kvm_info("HYP mode not available\n"); 2200 return -ENODEV; 2201 } 2202 2203 if (kvm_get_mode() == KVM_MODE_NONE) { 2204 kvm_info("KVM disabled from command line\n"); 2205 return -ENODEV; 2206 } 2207 2208 err = kvm_sys_reg_table_init(); 2209 if (err) { 2210 kvm_info("Error initializing system register tables"); 2211 return err; 2212 } 2213 2214 in_hyp_mode = is_kernel_in_hyp_mode(); 2215 2216 if (cpus_have_final_cap(ARM64_WORKAROUND_DEVICE_LOAD_ACQUIRE) || 2217 cpus_have_final_cap(ARM64_WORKAROUND_1508412)) 2218 kvm_info("Guests without required CPU erratum workarounds can deadlock system!\n" \ 2219 "Only trusted guests should be used on this system.\n"); 2220 2221 err = kvm_set_ipa_limit(); 2222 if (err) 2223 return err; 2224 2225 err = kvm_arm_init_sve(); 2226 if (err) 2227 return err; 2228 2229 err = kvm_arm_vmid_alloc_init(); 2230 if (err) { 2231 kvm_err("Failed to initialize VMID allocator.\n"); 2232 return err; 2233 } 2234 2235 if (!in_hyp_mode) { 2236 err = init_hyp_mode(); 2237 if (err) 2238 goto out_err; 2239 } 2240 2241 err = kvm_init_vector_slots(); 2242 if (err) { 2243 kvm_err("Cannot initialise vector slots\n"); 2244 goto out_err; 2245 } 2246 2247 err = init_subsystems(); 2248 if (err) 2249 goto out_hyp; 2250 2251 if (!in_hyp_mode) { 2252 err = finalize_hyp_mode(); 2253 if (err) { 2254 kvm_err("Failed to finalize Hyp protection\n"); 2255 goto out_hyp; 2256 } 2257 } 2258 2259 if (is_protected_kvm_enabled()) { 2260 kvm_info("Protected nVHE mode initialized successfully\n"); 2261 } else if (in_hyp_mode) { 2262 kvm_info("VHE mode initialized successfully\n"); 2263 } else { 2264 kvm_info("Hyp mode initialized successfully\n"); 2265 } 2266 2267 return 0; 2268 2269 out_hyp: 2270 hyp_cpu_pm_exit(); 2271 if (!in_hyp_mode) 2272 teardown_hyp_mode(); 2273 out_err: 2274 kvm_arm_vmid_alloc_free(); 2275 return err; 2276 } 2277 2278 /* NOP: Compiling as a module not supported */ 2279 void kvm_arch_exit(void) 2280 { 2281 kvm_unregister_perf_callbacks(); 2282 } 2283 2284 static int __init early_kvm_mode_cfg(char *arg) 2285 { 2286 if (!arg) 2287 return -EINVAL; 2288 2289 if (strcmp(arg, "none") == 0) { 2290 kvm_mode = KVM_MODE_NONE; 2291 return 0; 2292 } 2293 2294 if (!is_hyp_mode_available()) { 2295 pr_warn_once("KVM is not available. Ignoring kvm-arm.mode\n"); 2296 return 0; 2297 } 2298 2299 if (strcmp(arg, "protected") == 0) { 2300 if (!is_kernel_in_hyp_mode()) 2301 kvm_mode = KVM_MODE_PROTECTED; 2302 else 2303 pr_warn_once("Protected KVM not available with VHE\n"); 2304 2305 return 0; 2306 } 2307 2308 if (strcmp(arg, "nvhe") == 0 && !WARN_ON(is_kernel_in_hyp_mode())) { 2309 kvm_mode = KVM_MODE_DEFAULT; 2310 return 0; 2311 } 2312 2313 return -EINVAL; 2314 } 2315 early_param("kvm-arm.mode", early_kvm_mode_cfg); 2316 2317 enum kvm_mode kvm_get_mode(void) 2318 { 2319 return kvm_mode; 2320 } 2321 2322 static int arm_init(void) 2323 { 2324 int rc = kvm_init(NULL, sizeof(struct kvm_vcpu), 0, THIS_MODULE); 2325 return rc; 2326 } 2327 2328 module_init(arm_init); 2329