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