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_emulate.h> 41 #include <asm/sections.h> 42 43 #include <kvm/arm_hypercalls.h> 44 #include <kvm/arm_pmu.h> 45 #include <kvm/arm_psci.h> 46 47 static enum kvm_mode kvm_mode = KVM_MODE_DEFAULT; 48 DEFINE_STATIC_KEY_FALSE(kvm_protected_mode_initialized); 49 50 DECLARE_KVM_HYP_PER_CPU(unsigned long, kvm_hyp_vector); 51 52 static DEFINE_PER_CPU(unsigned long, kvm_arm_hyp_stack_page); 53 unsigned long kvm_arm_hyp_percpu_base[NR_CPUS]; 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_arm_setup_stage2(kvm, type); 142 if (ret) 143 return ret; 144 145 ret = kvm_init_stage2_mmu(kvm, &kvm->arch.mmu); 146 if (ret) 147 return ret; 148 149 ret = kvm_share_hyp(kvm, kvm + 1); 150 if (ret) 151 goto out_free_stage2_pgd; 152 153 if (!zalloc_cpumask_var(&kvm->arch.supported_cpus, GFP_KERNEL)) 154 goto out_free_stage2_pgd; 155 cpumask_copy(kvm->arch.supported_cpus, cpu_possible_mask); 156 157 kvm_vgic_early_init(kvm); 158 159 /* The maximum number of VCPUs is limited by the host's GIC model */ 160 kvm->max_vcpus = kvm_arm_default_max_vcpus(); 161 162 set_default_spectre(kvm); 163 kvm_arm_init_hypercalls(kvm); 164 165 return ret; 166 out_free_stage2_pgd: 167 kvm_free_stage2_pgd(&kvm->arch.mmu); 168 return ret; 169 } 170 171 vm_fault_t kvm_arch_vcpu_fault(struct kvm_vcpu *vcpu, struct vm_fault *vmf) 172 { 173 return VM_FAULT_SIGBUS; 174 } 175 176 177 /** 178 * kvm_arch_destroy_vm - destroy the VM data structure 179 * @kvm: pointer to the KVM struct 180 */ 181 void kvm_arch_destroy_vm(struct kvm *kvm) 182 { 183 bitmap_free(kvm->arch.pmu_filter); 184 free_cpumask_var(kvm->arch.supported_cpus); 185 186 kvm_vgic_destroy(kvm); 187 188 kvm_destroy_vcpus(kvm); 189 190 kvm_unshare_hyp(kvm, kvm + 1); 191 } 192 193 int kvm_vm_ioctl_check_extension(struct kvm *kvm, long ext) 194 { 195 int r; 196 switch (ext) { 197 case KVM_CAP_IRQCHIP: 198 r = vgic_present; 199 break; 200 case KVM_CAP_IOEVENTFD: 201 case KVM_CAP_DEVICE_CTRL: 202 case KVM_CAP_USER_MEMORY: 203 case KVM_CAP_SYNC_MMU: 204 case KVM_CAP_DESTROY_MEMORY_REGION_WORKS: 205 case KVM_CAP_ONE_REG: 206 case KVM_CAP_ARM_PSCI: 207 case KVM_CAP_ARM_PSCI_0_2: 208 case KVM_CAP_READONLY_MEM: 209 case KVM_CAP_MP_STATE: 210 case KVM_CAP_IMMEDIATE_EXIT: 211 case KVM_CAP_VCPU_EVENTS: 212 case KVM_CAP_ARM_IRQ_LINE_LAYOUT_2: 213 case KVM_CAP_ARM_NISV_TO_USER: 214 case KVM_CAP_ARM_INJECT_EXT_DABT: 215 case KVM_CAP_SET_GUEST_DEBUG: 216 case KVM_CAP_VCPU_ATTRIBUTES: 217 case KVM_CAP_PTP_KVM: 218 case KVM_CAP_ARM_SYSTEM_SUSPEND: 219 r = 1; 220 break; 221 case KVM_CAP_SET_GUEST_DEBUG2: 222 return KVM_GUESTDBG_VALID_MASK; 223 case KVM_CAP_ARM_SET_DEVICE_ADDR: 224 r = 1; 225 break; 226 case KVM_CAP_NR_VCPUS: 227 /* 228 * ARM64 treats KVM_CAP_NR_CPUS differently from all other 229 * architectures, as it does not always bound it to 230 * KVM_CAP_MAX_VCPUS. It should not matter much because 231 * this is just an advisory value. 232 */ 233 r = min_t(unsigned int, num_online_cpus(), 234 kvm_arm_default_max_vcpus()); 235 break; 236 case KVM_CAP_MAX_VCPUS: 237 case KVM_CAP_MAX_VCPU_ID: 238 if (kvm) 239 r = kvm->max_vcpus; 240 else 241 r = kvm_arm_default_max_vcpus(); 242 break; 243 case KVM_CAP_MSI_DEVID: 244 if (!kvm) 245 r = -EINVAL; 246 else 247 r = kvm->arch.vgic.msis_require_devid; 248 break; 249 case KVM_CAP_ARM_USER_IRQ: 250 /* 251 * 1: EL1_VTIMER, EL1_PTIMER, and PMU. 252 * (bump this number if adding more devices) 253 */ 254 r = 1; 255 break; 256 case KVM_CAP_ARM_MTE: 257 r = system_supports_mte(); 258 break; 259 case KVM_CAP_STEAL_TIME: 260 r = kvm_arm_pvtime_supported(); 261 break; 262 case KVM_CAP_ARM_EL1_32BIT: 263 r = cpus_have_const_cap(ARM64_HAS_32BIT_EL1); 264 break; 265 case KVM_CAP_GUEST_DEBUG_HW_BPS: 266 r = get_num_brps(); 267 break; 268 case KVM_CAP_GUEST_DEBUG_HW_WPS: 269 r = get_num_wrps(); 270 break; 271 case KVM_CAP_ARM_PMU_V3: 272 r = kvm_arm_support_pmu_v3(); 273 break; 274 case KVM_CAP_ARM_INJECT_SERROR_ESR: 275 r = cpus_have_const_cap(ARM64_HAS_RAS_EXTN); 276 break; 277 case KVM_CAP_ARM_VM_IPA_SIZE: 278 r = get_kvm_ipa_limit(); 279 break; 280 case KVM_CAP_ARM_SVE: 281 r = system_supports_sve(); 282 break; 283 case KVM_CAP_ARM_PTRAUTH_ADDRESS: 284 case KVM_CAP_ARM_PTRAUTH_GENERIC: 285 r = system_has_full_ptr_auth(); 286 break; 287 default: 288 r = 0; 289 } 290 291 return r; 292 } 293 294 long kvm_arch_dev_ioctl(struct file *filp, 295 unsigned int ioctl, unsigned long arg) 296 { 297 return -EINVAL; 298 } 299 300 struct kvm *kvm_arch_alloc_vm(void) 301 { 302 size_t sz = sizeof(struct kvm); 303 304 if (!has_vhe()) 305 return kzalloc(sz, GFP_KERNEL_ACCOUNT); 306 307 return __vmalloc(sz, GFP_KERNEL_ACCOUNT | __GFP_HIGHMEM | __GFP_ZERO); 308 } 309 310 int kvm_arch_vcpu_precreate(struct kvm *kvm, unsigned int id) 311 { 312 if (irqchip_in_kernel(kvm) && vgic_initialized(kvm)) 313 return -EBUSY; 314 315 if (id >= kvm->max_vcpus) 316 return -EINVAL; 317 318 return 0; 319 } 320 321 int kvm_arch_vcpu_create(struct kvm_vcpu *vcpu) 322 { 323 int err; 324 325 /* Force users to call KVM_ARM_VCPU_INIT */ 326 vcpu->arch.target = -1; 327 bitmap_zero(vcpu->arch.features, KVM_VCPU_MAX_FEATURES); 328 329 vcpu->arch.mmu_page_cache.gfp_zero = __GFP_ZERO; 330 331 /* Set up the timer */ 332 kvm_timer_vcpu_init(vcpu); 333 334 kvm_pmu_vcpu_init(vcpu); 335 336 kvm_arm_reset_debug_ptr(vcpu); 337 338 kvm_arm_pvtime_vcpu_init(&vcpu->arch); 339 340 vcpu->arch.hw_mmu = &vcpu->kvm->arch.mmu; 341 342 err = kvm_vgic_vcpu_init(vcpu); 343 if (err) 344 return err; 345 346 return kvm_share_hyp(vcpu, vcpu + 1); 347 } 348 349 void kvm_arch_vcpu_postcreate(struct kvm_vcpu *vcpu) 350 { 351 } 352 353 void kvm_arch_vcpu_destroy(struct kvm_vcpu *vcpu) 354 { 355 if (vcpu_has_run_once(vcpu) && unlikely(!irqchip_in_kernel(vcpu->kvm))) 356 static_branch_dec(&userspace_irqchip_in_use); 357 358 kvm_mmu_free_memory_cache(&vcpu->arch.mmu_page_cache); 359 kvm_timer_vcpu_terminate(vcpu); 360 kvm_pmu_vcpu_destroy(vcpu); 361 362 kvm_arm_vcpu_destroy(vcpu); 363 } 364 365 void kvm_arch_vcpu_blocking(struct kvm_vcpu *vcpu) 366 { 367 368 } 369 370 void kvm_arch_vcpu_unblocking(struct kvm_vcpu *vcpu) 371 { 372 373 } 374 375 void kvm_arch_vcpu_load(struct kvm_vcpu *vcpu, int cpu) 376 { 377 struct kvm_s2_mmu *mmu; 378 int *last_ran; 379 380 mmu = vcpu->arch.hw_mmu; 381 last_ran = this_cpu_ptr(mmu->last_vcpu_ran); 382 383 /* 384 * We guarantee that both TLBs and I-cache are private to each 385 * vcpu. If detecting that a vcpu from the same VM has 386 * previously run on the same physical CPU, call into the 387 * hypervisor code to nuke the relevant contexts. 388 * 389 * We might get preempted before the vCPU actually runs, but 390 * over-invalidation doesn't affect correctness. 391 */ 392 if (*last_ran != vcpu->vcpu_id) { 393 kvm_call_hyp(__kvm_flush_cpu_context, mmu); 394 *last_ran = vcpu->vcpu_id; 395 } 396 397 vcpu->cpu = cpu; 398 399 kvm_vgic_load(vcpu); 400 kvm_timer_vcpu_load(vcpu); 401 if (has_vhe()) 402 kvm_vcpu_load_sysregs_vhe(vcpu); 403 kvm_arch_vcpu_load_fp(vcpu); 404 kvm_vcpu_pmu_restore_guest(vcpu); 405 if (kvm_arm_is_pvtime_enabled(&vcpu->arch)) 406 kvm_make_request(KVM_REQ_RECORD_STEAL, vcpu); 407 408 if (single_task_running()) 409 vcpu_clear_wfx_traps(vcpu); 410 else 411 vcpu_set_wfx_traps(vcpu); 412 413 if (vcpu_has_ptrauth(vcpu)) 414 vcpu_ptrauth_disable(vcpu); 415 kvm_arch_vcpu_load_debug_state_flags(vcpu); 416 417 if (!cpumask_test_cpu(smp_processor_id(), vcpu->kvm->arch.supported_cpus)) 418 vcpu_set_on_unsupported_cpu(vcpu); 419 } 420 421 void kvm_arch_vcpu_put(struct kvm_vcpu *vcpu) 422 { 423 kvm_arch_vcpu_put_debug_state_flags(vcpu); 424 kvm_arch_vcpu_put_fp(vcpu); 425 if (has_vhe()) 426 kvm_vcpu_put_sysregs_vhe(vcpu); 427 kvm_timer_vcpu_put(vcpu); 428 kvm_vgic_put(vcpu); 429 kvm_vcpu_pmu_restore_host(vcpu); 430 kvm_arm_vmid_clear_active(); 431 432 vcpu_clear_on_unsupported_cpu(vcpu); 433 vcpu->cpu = -1; 434 } 435 436 void kvm_arm_vcpu_power_off(struct kvm_vcpu *vcpu) 437 { 438 vcpu->arch.mp_state.mp_state = KVM_MP_STATE_STOPPED; 439 kvm_make_request(KVM_REQ_SLEEP, vcpu); 440 kvm_vcpu_kick(vcpu); 441 } 442 443 bool kvm_arm_vcpu_stopped(struct kvm_vcpu *vcpu) 444 { 445 return vcpu->arch.mp_state.mp_state == KVM_MP_STATE_STOPPED; 446 } 447 448 static void kvm_arm_vcpu_suspend(struct kvm_vcpu *vcpu) 449 { 450 vcpu->arch.mp_state.mp_state = KVM_MP_STATE_SUSPENDED; 451 kvm_make_request(KVM_REQ_SUSPEND, vcpu); 452 kvm_vcpu_kick(vcpu); 453 } 454 455 static bool kvm_arm_vcpu_suspended(struct kvm_vcpu *vcpu) 456 { 457 return vcpu->arch.mp_state.mp_state == KVM_MP_STATE_SUSPENDED; 458 } 459 460 int kvm_arch_vcpu_ioctl_get_mpstate(struct kvm_vcpu *vcpu, 461 struct kvm_mp_state *mp_state) 462 { 463 *mp_state = vcpu->arch.mp_state; 464 465 return 0; 466 } 467 468 int kvm_arch_vcpu_ioctl_set_mpstate(struct kvm_vcpu *vcpu, 469 struct kvm_mp_state *mp_state) 470 { 471 int ret = 0; 472 473 switch (mp_state->mp_state) { 474 case KVM_MP_STATE_RUNNABLE: 475 vcpu->arch.mp_state = *mp_state; 476 break; 477 case KVM_MP_STATE_STOPPED: 478 kvm_arm_vcpu_power_off(vcpu); 479 break; 480 case KVM_MP_STATE_SUSPENDED: 481 kvm_arm_vcpu_suspend(vcpu); 482 break; 483 default: 484 ret = -EINVAL; 485 } 486 487 return ret; 488 } 489 490 /** 491 * kvm_arch_vcpu_runnable - determine if the vcpu can be scheduled 492 * @v: The VCPU pointer 493 * 494 * If the guest CPU is not waiting for interrupts or an interrupt line is 495 * asserted, the CPU is by definition runnable. 496 */ 497 int kvm_arch_vcpu_runnable(struct kvm_vcpu *v) 498 { 499 bool irq_lines = *vcpu_hcr(v) & (HCR_VI | HCR_VF); 500 return ((irq_lines || kvm_vgic_vcpu_pending_irq(v)) 501 && !kvm_arm_vcpu_stopped(v) && !v->arch.pause); 502 } 503 504 bool kvm_arch_vcpu_in_kernel(struct kvm_vcpu *vcpu) 505 { 506 return vcpu_mode_priv(vcpu); 507 } 508 509 #ifdef CONFIG_GUEST_PERF_EVENTS 510 unsigned long kvm_arch_vcpu_get_ip(struct kvm_vcpu *vcpu) 511 { 512 return *vcpu_pc(vcpu); 513 } 514 #endif 515 516 static int kvm_vcpu_initialized(struct kvm_vcpu *vcpu) 517 { 518 return vcpu->arch.target >= 0; 519 } 520 521 /* 522 * Handle both the initialisation that is being done when the vcpu is 523 * run for the first time, as well as the updates that must be 524 * performed each time we get a new thread dealing with this vcpu. 525 */ 526 int kvm_arch_vcpu_run_pid_change(struct kvm_vcpu *vcpu) 527 { 528 struct kvm *kvm = vcpu->kvm; 529 int ret; 530 531 if (!kvm_vcpu_initialized(vcpu)) 532 return -ENOEXEC; 533 534 if (!kvm_arm_vcpu_is_finalized(vcpu)) 535 return -EPERM; 536 537 ret = kvm_arch_vcpu_run_map_fp(vcpu); 538 if (ret) 539 return ret; 540 541 if (likely(vcpu_has_run_once(vcpu))) 542 return 0; 543 544 kvm_arm_vcpu_init_debug(vcpu); 545 546 if (likely(irqchip_in_kernel(kvm))) { 547 /* 548 * Map the VGIC hardware resources before running a vcpu the 549 * first time on this VM. 550 */ 551 ret = kvm_vgic_map_resources(kvm); 552 if (ret) 553 return ret; 554 } 555 556 ret = kvm_timer_enable(vcpu); 557 if (ret) 558 return ret; 559 560 ret = kvm_arm_pmu_v3_enable(vcpu); 561 if (ret) 562 return ret; 563 564 if (!irqchip_in_kernel(kvm)) { 565 /* 566 * Tell the rest of the code that there are userspace irqchip 567 * VMs in the wild. 568 */ 569 static_branch_inc(&userspace_irqchip_in_use); 570 } 571 572 /* 573 * Initialize traps for protected VMs. 574 * NOTE: Move to run in EL2 directly, rather than via a hypercall, once 575 * the code is in place for first run initialization at EL2. 576 */ 577 if (kvm_vm_is_protected(kvm)) 578 kvm_call_hyp_nvhe(__pkvm_vcpu_init_traps, vcpu); 579 580 mutex_lock(&kvm->lock); 581 set_bit(KVM_ARCH_FLAG_HAS_RAN_ONCE, &kvm->arch.flags); 582 mutex_unlock(&kvm->lock); 583 584 return ret; 585 } 586 587 bool kvm_arch_intc_initialized(struct kvm *kvm) 588 { 589 return vgic_initialized(kvm); 590 } 591 592 void kvm_arm_halt_guest(struct kvm *kvm) 593 { 594 unsigned long i; 595 struct kvm_vcpu *vcpu; 596 597 kvm_for_each_vcpu(i, vcpu, kvm) 598 vcpu->arch.pause = true; 599 kvm_make_all_cpus_request(kvm, KVM_REQ_SLEEP); 600 } 601 602 void kvm_arm_resume_guest(struct kvm *kvm) 603 { 604 unsigned long i; 605 struct kvm_vcpu *vcpu; 606 607 kvm_for_each_vcpu(i, vcpu, kvm) { 608 vcpu->arch.pause = false; 609 __kvm_vcpu_wake_up(vcpu); 610 } 611 } 612 613 static void kvm_vcpu_sleep(struct kvm_vcpu *vcpu) 614 { 615 struct rcuwait *wait = kvm_arch_vcpu_get_wait(vcpu); 616 617 rcuwait_wait_event(wait, 618 (!kvm_arm_vcpu_stopped(vcpu)) && (!vcpu->arch.pause), 619 TASK_INTERRUPTIBLE); 620 621 if (kvm_arm_vcpu_stopped(vcpu) || vcpu->arch.pause) { 622 /* Awaken to handle a signal, request we sleep again later. */ 623 kvm_make_request(KVM_REQ_SLEEP, vcpu); 624 } 625 626 /* 627 * Make sure we will observe a potential reset request if we've 628 * observed a change to the power state. Pairs with the smp_wmb() in 629 * kvm_psci_vcpu_on(). 630 */ 631 smp_rmb(); 632 } 633 634 /** 635 * kvm_vcpu_wfi - emulate Wait-For-Interrupt behavior 636 * @vcpu: The VCPU pointer 637 * 638 * Suspend execution of a vCPU until a valid wake event is detected, i.e. until 639 * the vCPU is runnable. The vCPU may or may not be scheduled out, depending 640 * on when a wake event arrives, e.g. there may already be a pending wake event. 641 */ 642 void kvm_vcpu_wfi(struct kvm_vcpu *vcpu) 643 { 644 /* 645 * Sync back the state of the GIC CPU interface so that we have 646 * the latest PMR and group enables. This ensures that 647 * kvm_arch_vcpu_runnable has up-to-date data to decide whether 648 * we have pending interrupts, e.g. when determining if the 649 * vCPU should block. 650 * 651 * For the same reason, we want to tell GICv4 that we need 652 * doorbells to be signalled, should an interrupt become pending. 653 */ 654 preempt_disable(); 655 kvm_vgic_vmcr_sync(vcpu); 656 vgic_v4_put(vcpu, true); 657 preempt_enable(); 658 659 kvm_vcpu_halt(vcpu); 660 vcpu->arch.flags &= ~KVM_ARM64_WFIT; 661 kvm_clear_request(KVM_REQ_UNHALT, vcpu); 662 663 preempt_disable(); 664 vgic_v4_load(vcpu); 665 preempt_enable(); 666 } 667 668 static int kvm_vcpu_suspend(struct kvm_vcpu *vcpu) 669 { 670 if (!kvm_arm_vcpu_suspended(vcpu)) 671 return 1; 672 673 kvm_vcpu_wfi(vcpu); 674 675 /* 676 * The suspend state is sticky; we do not leave it until userspace 677 * explicitly marks the vCPU as runnable. Request that we suspend again 678 * later. 679 */ 680 kvm_make_request(KVM_REQ_SUSPEND, vcpu); 681 682 /* 683 * Check to make sure the vCPU is actually runnable. If so, exit to 684 * userspace informing it of the wakeup condition. 685 */ 686 if (kvm_arch_vcpu_runnable(vcpu)) { 687 memset(&vcpu->run->system_event, 0, sizeof(vcpu->run->system_event)); 688 vcpu->run->system_event.type = KVM_SYSTEM_EVENT_WAKEUP; 689 vcpu->run->exit_reason = KVM_EXIT_SYSTEM_EVENT; 690 return 0; 691 } 692 693 /* 694 * Otherwise, we were unblocked to process a different event, such as a 695 * pending signal. Return 1 and allow kvm_arch_vcpu_ioctl_run() to 696 * process the event. 697 */ 698 return 1; 699 } 700 701 /** 702 * check_vcpu_requests - check and handle pending vCPU requests 703 * @vcpu: the VCPU pointer 704 * 705 * Return: 1 if we should enter the guest 706 * 0 if we should exit to userspace 707 * < 0 if we should exit to userspace, where the return value indicates 708 * an error 709 */ 710 static int check_vcpu_requests(struct kvm_vcpu *vcpu) 711 { 712 if (kvm_request_pending(vcpu)) { 713 if (kvm_check_request(KVM_REQ_SLEEP, vcpu)) 714 kvm_vcpu_sleep(vcpu); 715 716 if (kvm_check_request(KVM_REQ_VCPU_RESET, vcpu)) 717 kvm_reset_vcpu(vcpu); 718 719 /* 720 * Clear IRQ_PENDING requests that were made to guarantee 721 * that a VCPU sees new virtual interrupts. 722 */ 723 kvm_check_request(KVM_REQ_IRQ_PENDING, vcpu); 724 725 if (kvm_check_request(KVM_REQ_RECORD_STEAL, vcpu)) 726 kvm_update_stolen_time(vcpu); 727 728 if (kvm_check_request(KVM_REQ_RELOAD_GICv4, vcpu)) { 729 /* The distributor enable bits were changed */ 730 preempt_disable(); 731 vgic_v4_put(vcpu, false); 732 vgic_v4_load(vcpu); 733 preempt_enable(); 734 } 735 736 if (kvm_check_request(KVM_REQ_RELOAD_PMU, vcpu)) 737 kvm_pmu_handle_pmcr(vcpu, 738 __vcpu_sys_reg(vcpu, PMCR_EL0)); 739 740 if (kvm_check_request(KVM_REQ_SUSPEND, vcpu)) 741 return kvm_vcpu_suspend(vcpu); 742 } 743 744 return 1; 745 } 746 747 static bool vcpu_mode_is_bad_32bit(struct kvm_vcpu *vcpu) 748 { 749 if (likely(!vcpu_mode_is_32bit(vcpu))) 750 return false; 751 752 return !system_supports_32bit_el0() || 753 static_branch_unlikely(&arm64_mismatched_32bit_el0); 754 } 755 756 /** 757 * kvm_vcpu_exit_request - returns true if the VCPU should *not* enter the guest 758 * @vcpu: The VCPU pointer 759 * @ret: Pointer to write optional return code 760 * 761 * Returns: true if the VCPU needs to return to a preemptible + interruptible 762 * and skip guest entry. 763 * 764 * This function disambiguates between two different types of exits: exits to a 765 * preemptible + interruptible kernel context and exits to userspace. For an 766 * exit to userspace, this function will write the return code to ret and return 767 * true. For an exit to preemptible + interruptible kernel context (i.e. check 768 * for pending work and re-enter), return true without writing to ret. 769 */ 770 static bool kvm_vcpu_exit_request(struct kvm_vcpu *vcpu, int *ret) 771 { 772 struct kvm_run *run = vcpu->run; 773 774 /* 775 * If we're using a userspace irqchip, then check if we need 776 * to tell a userspace irqchip about timer or PMU level 777 * changes and if so, exit to userspace (the actual level 778 * state gets updated in kvm_timer_update_run and 779 * kvm_pmu_update_run below). 780 */ 781 if (static_branch_unlikely(&userspace_irqchip_in_use)) { 782 if (kvm_timer_should_notify_user(vcpu) || 783 kvm_pmu_should_notify_user(vcpu)) { 784 *ret = -EINTR; 785 run->exit_reason = KVM_EXIT_INTR; 786 return true; 787 } 788 } 789 790 if (unlikely(vcpu_on_unsupported_cpu(vcpu))) { 791 run->exit_reason = KVM_EXIT_FAIL_ENTRY; 792 run->fail_entry.hardware_entry_failure_reason = KVM_EXIT_FAIL_ENTRY_CPU_UNSUPPORTED; 793 run->fail_entry.cpu = smp_processor_id(); 794 *ret = 0; 795 return true; 796 } 797 798 return kvm_request_pending(vcpu) || 799 xfer_to_guest_mode_work_pending(); 800 } 801 802 /* 803 * Actually run the vCPU, entering an RCU extended quiescent state (EQS) while 804 * the vCPU is running. 805 * 806 * This must be noinstr as instrumentation may make use of RCU, and this is not 807 * safe during the EQS. 808 */ 809 static int noinstr kvm_arm_vcpu_enter_exit(struct kvm_vcpu *vcpu) 810 { 811 int ret; 812 813 guest_state_enter_irqoff(); 814 ret = kvm_call_hyp_ret(__kvm_vcpu_run, vcpu); 815 guest_state_exit_irqoff(); 816 817 return ret; 818 } 819 820 /** 821 * kvm_arch_vcpu_ioctl_run - the main VCPU run function to execute guest code 822 * @vcpu: The VCPU pointer 823 * 824 * This function is called through the VCPU_RUN ioctl called from user space. It 825 * will execute VM code in a loop until the time slice for the process is used 826 * or some emulation is needed from user space in which case the function will 827 * return with return value 0 and with the kvm_run structure filled in with the 828 * required data for the requested emulation. 829 */ 830 int kvm_arch_vcpu_ioctl_run(struct kvm_vcpu *vcpu) 831 { 832 struct kvm_run *run = vcpu->run; 833 int ret; 834 835 if (run->exit_reason == KVM_EXIT_MMIO) { 836 ret = kvm_handle_mmio_return(vcpu); 837 if (ret) 838 return ret; 839 } 840 841 vcpu_load(vcpu); 842 843 if (run->immediate_exit) { 844 ret = -EINTR; 845 goto out; 846 } 847 848 kvm_sigset_activate(vcpu); 849 850 ret = 1; 851 run->exit_reason = KVM_EXIT_UNKNOWN; 852 run->flags = 0; 853 while (ret > 0) { 854 /* 855 * Check conditions before entering the guest 856 */ 857 ret = xfer_to_guest_mode_handle_work(vcpu); 858 if (!ret) 859 ret = 1; 860 861 if (ret > 0) 862 ret = check_vcpu_requests(vcpu); 863 864 /* 865 * Preparing the interrupts to be injected also 866 * involves poking the GIC, which must be done in a 867 * non-preemptible context. 868 */ 869 preempt_disable(); 870 871 /* 872 * The VMID allocator only tracks active VMIDs per 873 * physical CPU, and therefore the VMID allocated may not be 874 * preserved on VMID roll-over if the task was preempted, 875 * making a thread's VMID inactive. So we need to call 876 * kvm_arm_vmid_update() in non-premptible context. 877 */ 878 kvm_arm_vmid_update(&vcpu->arch.hw_mmu->vmid); 879 880 kvm_pmu_flush_hwstate(vcpu); 881 882 local_irq_disable(); 883 884 kvm_vgic_flush_hwstate(vcpu); 885 886 kvm_pmu_update_vcpu_events(vcpu); 887 888 /* 889 * Ensure we set mode to IN_GUEST_MODE after we disable 890 * interrupts and before the final VCPU requests check. 891 * See the comment in kvm_vcpu_exiting_guest_mode() and 892 * Documentation/virt/kvm/vcpu-requests.rst 893 */ 894 smp_store_mb(vcpu->mode, IN_GUEST_MODE); 895 896 if (ret <= 0 || kvm_vcpu_exit_request(vcpu, &ret)) { 897 vcpu->mode = OUTSIDE_GUEST_MODE; 898 isb(); /* Ensure work in x_flush_hwstate is committed */ 899 kvm_pmu_sync_hwstate(vcpu); 900 if (static_branch_unlikely(&userspace_irqchip_in_use)) 901 kvm_timer_sync_user(vcpu); 902 kvm_vgic_sync_hwstate(vcpu); 903 local_irq_enable(); 904 preempt_enable(); 905 continue; 906 } 907 908 kvm_arm_setup_debug(vcpu); 909 kvm_arch_vcpu_ctxflush_fp(vcpu); 910 911 /************************************************************** 912 * Enter the guest 913 */ 914 trace_kvm_entry(*vcpu_pc(vcpu)); 915 guest_timing_enter_irqoff(); 916 917 ret = kvm_arm_vcpu_enter_exit(vcpu); 918 919 vcpu->mode = OUTSIDE_GUEST_MODE; 920 vcpu->stat.exits++; 921 /* 922 * Back from guest 923 *************************************************************/ 924 925 kvm_arm_clear_debug(vcpu); 926 927 /* 928 * We must sync the PMU state before the vgic state so 929 * that the vgic can properly sample the updated state of the 930 * interrupt line. 931 */ 932 kvm_pmu_sync_hwstate(vcpu); 933 934 /* 935 * Sync the vgic state before syncing the timer state because 936 * the timer code needs to know if the virtual timer 937 * interrupts are active. 938 */ 939 kvm_vgic_sync_hwstate(vcpu); 940 941 /* 942 * Sync the timer hardware state before enabling interrupts as 943 * we don't want vtimer interrupts to race with syncing the 944 * timer virtual interrupt state. 945 */ 946 if (static_branch_unlikely(&userspace_irqchip_in_use)) 947 kvm_timer_sync_user(vcpu); 948 949 kvm_arch_vcpu_ctxsync_fp(vcpu); 950 951 /* 952 * We must ensure that any pending interrupts are taken before 953 * we exit guest timing so that timer ticks are accounted as 954 * guest time. Transiently unmask interrupts so that any 955 * pending interrupts are taken. 956 * 957 * Per ARM DDI 0487G.b section D1.13.4, an ISB (or other 958 * context synchronization event) is necessary to ensure that 959 * pending interrupts are taken. 960 */ 961 if (ARM_EXCEPTION_CODE(ret) == ARM_EXCEPTION_IRQ) { 962 local_irq_enable(); 963 isb(); 964 local_irq_disable(); 965 } 966 967 guest_timing_exit_irqoff(); 968 969 local_irq_enable(); 970 971 trace_kvm_exit(ret, kvm_vcpu_trap_get_class(vcpu), *vcpu_pc(vcpu)); 972 973 /* Exit types that need handling before we can be preempted */ 974 handle_exit_early(vcpu, ret); 975 976 preempt_enable(); 977 978 /* 979 * The ARMv8 architecture doesn't give the hypervisor 980 * a mechanism to prevent a guest from dropping to AArch32 EL0 981 * if implemented by the CPU. If we spot the guest in such 982 * state and that we decided it wasn't supposed to do so (like 983 * with the asymmetric AArch32 case), return to userspace with 984 * a fatal error. 985 */ 986 if (vcpu_mode_is_bad_32bit(vcpu)) { 987 /* 988 * As we have caught the guest red-handed, decide that 989 * it isn't fit for purpose anymore by making the vcpu 990 * invalid. The VMM can try and fix it by issuing a 991 * KVM_ARM_VCPU_INIT if it really wants to. 992 */ 993 vcpu->arch.target = -1; 994 ret = ARM_EXCEPTION_IL; 995 } 996 997 ret = handle_exit(vcpu, ret); 998 } 999 1000 /* Tell userspace about in-kernel device output levels */ 1001 if (unlikely(!irqchip_in_kernel(vcpu->kvm))) { 1002 kvm_timer_update_run(vcpu); 1003 kvm_pmu_update_run(vcpu); 1004 } 1005 1006 kvm_sigset_deactivate(vcpu); 1007 1008 out: 1009 /* 1010 * In the unlikely event that we are returning to userspace 1011 * with pending exceptions or PC adjustment, commit these 1012 * adjustments in order to give userspace a consistent view of 1013 * the vcpu state. Note that this relies on __kvm_adjust_pc() 1014 * being preempt-safe on VHE. 1015 */ 1016 if (unlikely(vcpu->arch.flags & (KVM_ARM64_PENDING_EXCEPTION | 1017 KVM_ARM64_INCREMENT_PC))) 1018 kvm_call_hyp(__kvm_adjust_pc, vcpu); 1019 1020 vcpu_put(vcpu); 1021 return ret; 1022 } 1023 1024 static int vcpu_interrupt_line(struct kvm_vcpu *vcpu, int number, bool level) 1025 { 1026 int bit_index; 1027 bool set; 1028 unsigned long *hcr; 1029 1030 if (number == KVM_ARM_IRQ_CPU_IRQ) 1031 bit_index = __ffs(HCR_VI); 1032 else /* KVM_ARM_IRQ_CPU_FIQ */ 1033 bit_index = __ffs(HCR_VF); 1034 1035 hcr = vcpu_hcr(vcpu); 1036 if (level) 1037 set = test_and_set_bit(bit_index, hcr); 1038 else 1039 set = test_and_clear_bit(bit_index, hcr); 1040 1041 /* 1042 * If we didn't change anything, no need to wake up or kick other CPUs 1043 */ 1044 if (set == level) 1045 return 0; 1046 1047 /* 1048 * The vcpu irq_lines field was updated, wake up sleeping VCPUs and 1049 * trigger a world-switch round on the running physical CPU to set the 1050 * virtual IRQ/FIQ fields in the HCR appropriately. 1051 */ 1052 kvm_make_request(KVM_REQ_IRQ_PENDING, vcpu); 1053 kvm_vcpu_kick(vcpu); 1054 1055 return 0; 1056 } 1057 1058 int kvm_vm_ioctl_irq_line(struct kvm *kvm, struct kvm_irq_level *irq_level, 1059 bool line_status) 1060 { 1061 u32 irq = irq_level->irq; 1062 unsigned int irq_type, vcpu_idx, irq_num; 1063 int nrcpus = atomic_read(&kvm->online_vcpus); 1064 struct kvm_vcpu *vcpu = NULL; 1065 bool level = irq_level->level; 1066 1067 irq_type = (irq >> KVM_ARM_IRQ_TYPE_SHIFT) & KVM_ARM_IRQ_TYPE_MASK; 1068 vcpu_idx = (irq >> KVM_ARM_IRQ_VCPU_SHIFT) & KVM_ARM_IRQ_VCPU_MASK; 1069 vcpu_idx += ((irq >> KVM_ARM_IRQ_VCPU2_SHIFT) & KVM_ARM_IRQ_VCPU2_MASK) * (KVM_ARM_IRQ_VCPU_MASK + 1); 1070 irq_num = (irq >> KVM_ARM_IRQ_NUM_SHIFT) & KVM_ARM_IRQ_NUM_MASK; 1071 1072 trace_kvm_irq_line(irq_type, vcpu_idx, irq_num, irq_level->level); 1073 1074 switch (irq_type) { 1075 case KVM_ARM_IRQ_TYPE_CPU: 1076 if (irqchip_in_kernel(kvm)) 1077 return -ENXIO; 1078 1079 if (vcpu_idx >= nrcpus) 1080 return -EINVAL; 1081 1082 vcpu = kvm_get_vcpu(kvm, vcpu_idx); 1083 if (!vcpu) 1084 return -EINVAL; 1085 1086 if (irq_num > KVM_ARM_IRQ_CPU_FIQ) 1087 return -EINVAL; 1088 1089 return vcpu_interrupt_line(vcpu, irq_num, level); 1090 case KVM_ARM_IRQ_TYPE_PPI: 1091 if (!irqchip_in_kernel(kvm)) 1092 return -ENXIO; 1093 1094 if (vcpu_idx >= nrcpus) 1095 return -EINVAL; 1096 1097 vcpu = kvm_get_vcpu(kvm, vcpu_idx); 1098 if (!vcpu) 1099 return -EINVAL; 1100 1101 if (irq_num < VGIC_NR_SGIS || irq_num >= VGIC_NR_PRIVATE_IRQS) 1102 return -EINVAL; 1103 1104 return kvm_vgic_inject_irq(kvm, vcpu->vcpu_id, irq_num, level, NULL); 1105 case KVM_ARM_IRQ_TYPE_SPI: 1106 if (!irqchip_in_kernel(kvm)) 1107 return -ENXIO; 1108 1109 if (irq_num < VGIC_NR_PRIVATE_IRQS) 1110 return -EINVAL; 1111 1112 return kvm_vgic_inject_irq(kvm, 0, irq_num, level, NULL); 1113 } 1114 1115 return -EINVAL; 1116 } 1117 1118 static int kvm_vcpu_set_target(struct kvm_vcpu *vcpu, 1119 const struct kvm_vcpu_init *init) 1120 { 1121 unsigned int i, ret; 1122 u32 phys_target = kvm_target_cpu(); 1123 1124 if (init->target != phys_target) 1125 return -EINVAL; 1126 1127 /* 1128 * Secondary and subsequent calls to KVM_ARM_VCPU_INIT must 1129 * use the same target. 1130 */ 1131 if (vcpu->arch.target != -1 && vcpu->arch.target != init->target) 1132 return -EINVAL; 1133 1134 /* -ENOENT for unknown features, -EINVAL for invalid combinations. */ 1135 for (i = 0; i < sizeof(init->features) * 8; i++) { 1136 bool set = (init->features[i / 32] & (1 << (i % 32))); 1137 1138 if (set && i >= KVM_VCPU_MAX_FEATURES) 1139 return -ENOENT; 1140 1141 /* 1142 * Secondary and subsequent calls to KVM_ARM_VCPU_INIT must 1143 * use the same feature set. 1144 */ 1145 if (vcpu->arch.target != -1 && i < KVM_VCPU_MAX_FEATURES && 1146 test_bit(i, vcpu->arch.features) != set) 1147 return -EINVAL; 1148 1149 if (set) 1150 set_bit(i, vcpu->arch.features); 1151 } 1152 1153 vcpu->arch.target = phys_target; 1154 1155 /* Now we know what it is, we can reset it. */ 1156 ret = kvm_reset_vcpu(vcpu); 1157 if (ret) { 1158 vcpu->arch.target = -1; 1159 bitmap_zero(vcpu->arch.features, KVM_VCPU_MAX_FEATURES); 1160 } 1161 1162 return ret; 1163 } 1164 1165 static int kvm_arch_vcpu_ioctl_vcpu_init(struct kvm_vcpu *vcpu, 1166 struct kvm_vcpu_init *init) 1167 { 1168 int ret; 1169 1170 ret = kvm_vcpu_set_target(vcpu, init); 1171 if (ret) 1172 return ret; 1173 1174 /* 1175 * Ensure a rebooted VM will fault in RAM pages and detect if the 1176 * guest MMU is turned off and flush the caches as needed. 1177 * 1178 * S2FWB enforces all memory accesses to RAM being cacheable, 1179 * ensuring that the data side is always coherent. We still 1180 * need to invalidate the I-cache though, as FWB does *not* 1181 * imply CTR_EL0.DIC. 1182 */ 1183 if (vcpu_has_run_once(vcpu)) { 1184 if (!cpus_have_final_cap(ARM64_HAS_STAGE2_FWB)) 1185 stage2_unmap_vm(vcpu->kvm); 1186 else 1187 icache_inval_all_pou(); 1188 } 1189 1190 vcpu_reset_hcr(vcpu); 1191 vcpu->arch.cptr_el2 = CPTR_EL2_DEFAULT; 1192 1193 /* 1194 * Handle the "start in power-off" case. 1195 */ 1196 if (test_bit(KVM_ARM_VCPU_POWER_OFF, vcpu->arch.features)) 1197 kvm_arm_vcpu_power_off(vcpu); 1198 else 1199 vcpu->arch.mp_state.mp_state = KVM_MP_STATE_RUNNABLE; 1200 1201 return 0; 1202 } 1203 1204 static int kvm_arm_vcpu_set_attr(struct kvm_vcpu *vcpu, 1205 struct kvm_device_attr *attr) 1206 { 1207 int ret = -ENXIO; 1208 1209 switch (attr->group) { 1210 default: 1211 ret = kvm_arm_vcpu_arch_set_attr(vcpu, attr); 1212 break; 1213 } 1214 1215 return ret; 1216 } 1217 1218 static int kvm_arm_vcpu_get_attr(struct kvm_vcpu *vcpu, 1219 struct kvm_device_attr *attr) 1220 { 1221 int ret = -ENXIO; 1222 1223 switch (attr->group) { 1224 default: 1225 ret = kvm_arm_vcpu_arch_get_attr(vcpu, attr); 1226 break; 1227 } 1228 1229 return ret; 1230 } 1231 1232 static int kvm_arm_vcpu_has_attr(struct kvm_vcpu *vcpu, 1233 struct kvm_device_attr *attr) 1234 { 1235 int ret = -ENXIO; 1236 1237 switch (attr->group) { 1238 default: 1239 ret = kvm_arm_vcpu_arch_has_attr(vcpu, attr); 1240 break; 1241 } 1242 1243 return ret; 1244 } 1245 1246 static int kvm_arm_vcpu_get_events(struct kvm_vcpu *vcpu, 1247 struct kvm_vcpu_events *events) 1248 { 1249 memset(events, 0, sizeof(*events)); 1250 1251 return __kvm_arm_vcpu_get_events(vcpu, events); 1252 } 1253 1254 static int kvm_arm_vcpu_set_events(struct kvm_vcpu *vcpu, 1255 struct kvm_vcpu_events *events) 1256 { 1257 int i; 1258 1259 /* check whether the reserved field is zero */ 1260 for (i = 0; i < ARRAY_SIZE(events->reserved); i++) 1261 if (events->reserved[i]) 1262 return -EINVAL; 1263 1264 /* check whether the pad field is zero */ 1265 for (i = 0; i < ARRAY_SIZE(events->exception.pad); i++) 1266 if (events->exception.pad[i]) 1267 return -EINVAL; 1268 1269 return __kvm_arm_vcpu_set_events(vcpu, events); 1270 } 1271 1272 long kvm_arch_vcpu_ioctl(struct file *filp, 1273 unsigned int ioctl, unsigned long arg) 1274 { 1275 struct kvm_vcpu *vcpu = filp->private_data; 1276 void __user *argp = (void __user *)arg; 1277 struct kvm_device_attr attr; 1278 long r; 1279 1280 switch (ioctl) { 1281 case KVM_ARM_VCPU_INIT: { 1282 struct kvm_vcpu_init init; 1283 1284 r = -EFAULT; 1285 if (copy_from_user(&init, argp, sizeof(init))) 1286 break; 1287 1288 r = kvm_arch_vcpu_ioctl_vcpu_init(vcpu, &init); 1289 break; 1290 } 1291 case KVM_SET_ONE_REG: 1292 case KVM_GET_ONE_REG: { 1293 struct kvm_one_reg reg; 1294 1295 r = -ENOEXEC; 1296 if (unlikely(!kvm_vcpu_initialized(vcpu))) 1297 break; 1298 1299 r = -EFAULT; 1300 if (copy_from_user(®, argp, sizeof(reg))) 1301 break; 1302 1303 /* 1304 * We could owe a reset due to PSCI. Handle the pending reset 1305 * here to ensure userspace register accesses are ordered after 1306 * the reset. 1307 */ 1308 if (kvm_check_request(KVM_REQ_VCPU_RESET, vcpu)) 1309 kvm_reset_vcpu(vcpu); 1310 1311 if (ioctl == KVM_SET_ONE_REG) 1312 r = kvm_arm_set_reg(vcpu, ®); 1313 else 1314 r = kvm_arm_get_reg(vcpu, ®); 1315 break; 1316 } 1317 case KVM_GET_REG_LIST: { 1318 struct kvm_reg_list __user *user_list = argp; 1319 struct kvm_reg_list reg_list; 1320 unsigned n; 1321 1322 r = -ENOEXEC; 1323 if (unlikely(!kvm_vcpu_initialized(vcpu))) 1324 break; 1325 1326 r = -EPERM; 1327 if (!kvm_arm_vcpu_is_finalized(vcpu)) 1328 break; 1329 1330 r = -EFAULT; 1331 if (copy_from_user(®_list, user_list, sizeof(reg_list))) 1332 break; 1333 n = reg_list.n; 1334 reg_list.n = kvm_arm_num_regs(vcpu); 1335 if (copy_to_user(user_list, ®_list, sizeof(reg_list))) 1336 break; 1337 r = -E2BIG; 1338 if (n < reg_list.n) 1339 break; 1340 r = kvm_arm_copy_reg_indices(vcpu, user_list->reg); 1341 break; 1342 } 1343 case KVM_SET_DEVICE_ATTR: { 1344 r = -EFAULT; 1345 if (copy_from_user(&attr, argp, sizeof(attr))) 1346 break; 1347 r = kvm_arm_vcpu_set_attr(vcpu, &attr); 1348 break; 1349 } 1350 case KVM_GET_DEVICE_ATTR: { 1351 r = -EFAULT; 1352 if (copy_from_user(&attr, argp, sizeof(attr))) 1353 break; 1354 r = kvm_arm_vcpu_get_attr(vcpu, &attr); 1355 break; 1356 } 1357 case KVM_HAS_DEVICE_ATTR: { 1358 r = -EFAULT; 1359 if (copy_from_user(&attr, argp, sizeof(attr))) 1360 break; 1361 r = kvm_arm_vcpu_has_attr(vcpu, &attr); 1362 break; 1363 } 1364 case KVM_GET_VCPU_EVENTS: { 1365 struct kvm_vcpu_events events; 1366 1367 if (kvm_arm_vcpu_get_events(vcpu, &events)) 1368 return -EINVAL; 1369 1370 if (copy_to_user(argp, &events, sizeof(events))) 1371 return -EFAULT; 1372 1373 return 0; 1374 } 1375 case KVM_SET_VCPU_EVENTS: { 1376 struct kvm_vcpu_events events; 1377 1378 if (copy_from_user(&events, argp, sizeof(events))) 1379 return -EFAULT; 1380 1381 return kvm_arm_vcpu_set_events(vcpu, &events); 1382 } 1383 case KVM_ARM_VCPU_FINALIZE: { 1384 int what; 1385 1386 if (!kvm_vcpu_initialized(vcpu)) 1387 return -ENOEXEC; 1388 1389 if (get_user(what, (const int __user *)argp)) 1390 return -EFAULT; 1391 1392 return kvm_arm_vcpu_finalize(vcpu, what); 1393 } 1394 default: 1395 r = -EINVAL; 1396 } 1397 1398 return r; 1399 } 1400 1401 void kvm_arch_sync_dirty_log(struct kvm *kvm, struct kvm_memory_slot *memslot) 1402 { 1403 1404 } 1405 1406 void kvm_arch_flush_remote_tlbs_memslot(struct kvm *kvm, 1407 const struct kvm_memory_slot *memslot) 1408 { 1409 kvm_flush_remote_tlbs(kvm); 1410 } 1411 1412 static int kvm_vm_ioctl_set_device_addr(struct kvm *kvm, 1413 struct kvm_arm_device_addr *dev_addr) 1414 { 1415 unsigned long dev_id, type; 1416 1417 dev_id = (dev_addr->id & KVM_ARM_DEVICE_ID_MASK) >> 1418 KVM_ARM_DEVICE_ID_SHIFT; 1419 type = (dev_addr->id & KVM_ARM_DEVICE_TYPE_MASK) >> 1420 KVM_ARM_DEVICE_TYPE_SHIFT; 1421 1422 switch (dev_id) { 1423 case KVM_ARM_DEVICE_VGIC_V2: 1424 if (!vgic_present) 1425 return -ENXIO; 1426 return kvm_vgic_addr(kvm, type, &dev_addr->addr, true); 1427 default: 1428 return -ENODEV; 1429 } 1430 } 1431 1432 long kvm_arch_vm_ioctl(struct file *filp, 1433 unsigned int ioctl, unsigned long arg) 1434 { 1435 struct kvm *kvm = filp->private_data; 1436 void __user *argp = (void __user *)arg; 1437 1438 switch (ioctl) { 1439 case KVM_CREATE_IRQCHIP: { 1440 int ret; 1441 if (!vgic_present) 1442 return -ENXIO; 1443 mutex_lock(&kvm->lock); 1444 ret = kvm_vgic_create(kvm, KVM_DEV_TYPE_ARM_VGIC_V2); 1445 mutex_unlock(&kvm->lock); 1446 return ret; 1447 } 1448 case KVM_ARM_SET_DEVICE_ADDR: { 1449 struct kvm_arm_device_addr dev_addr; 1450 1451 if (copy_from_user(&dev_addr, argp, sizeof(dev_addr))) 1452 return -EFAULT; 1453 return kvm_vm_ioctl_set_device_addr(kvm, &dev_addr); 1454 } 1455 case KVM_ARM_PREFERRED_TARGET: { 1456 struct kvm_vcpu_init init; 1457 1458 kvm_vcpu_preferred_target(&init); 1459 1460 if (copy_to_user(argp, &init, sizeof(init))) 1461 return -EFAULT; 1462 1463 return 0; 1464 } 1465 case KVM_ARM_MTE_COPY_TAGS: { 1466 struct kvm_arm_copy_mte_tags copy_tags; 1467 1468 if (copy_from_user(©_tags, argp, sizeof(copy_tags))) 1469 return -EFAULT; 1470 return kvm_vm_ioctl_mte_copy_tags(kvm, ©_tags); 1471 } 1472 default: 1473 return -EINVAL; 1474 } 1475 } 1476 1477 static unsigned long nvhe_percpu_size(void) 1478 { 1479 return (unsigned long)CHOOSE_NVHE_SYM(__per_cpu_end) - 1480 (unsigned long)CHOOSE_NVHE_SYM(__per_cpu_start); 1481 } 1482 1483 static unsigned long nvhe_percpu_order(void) 1484 { 1485 unsigned long size = nvhe_percpu_size(); 1486 1487 return size ? get_order(size) : 0; 1488 } 1489 1490 /* A lookup table holding the hypervisor VA for each vector slot */ 1491 static void *hyp_spectre_vector_selector[BP_HARDEN_EL2_SLOTS]; 1492 1493 static void kvm_init_vector_slot(void *base, enum arm64_hyp_spectre_vector slot) 1494 { 1495 hyp_spectre_vector_selector[slot] = __kvm_vector_slot2addr(base, slot); 1496 } 1497 1498 static int kvm_init_vector_slots(void) 1499 { 1500 int err; 1501 void *base; 1502 1503 base = kern_hyp_va(kvm_ksym_ref(__kvm_hyp_vector)); 1504 kvm_init_vector_slot(base, HYP_VECTOR_DIRECT); 1505 1506 base = kern_hyp_va(kvm_ksym_ref(__bp_harden_hyp_vecs)); 1507 kvm_init_vector_slot(base, HYP_VECTOR_SPECTRE_DIRECT); 1508 1509 if (kvm_system_needs_idmapped_vectors() && 1510 !is_protected_kvm_enabled()) { 1511 err = create_hyp_exec_mappings(__pa_symbol(__bp_harden_hyp_vecs), 1512 __BP_HARDEN_HYP_VECS_SZ, &base); 1513 if (err) 1514 return err; 1515 } 1516 1517 kvm_init_vector_slot(base, HYP_VECTOR_INDIRECT); 1518 kvm_init_vector_slot(base, HYP_VECTOR_SPECTRE_INDIRECT); 1519 return 0; 1520 } 1521 1522 static void cpu_prepare_hyp_mode(int cpu) 1523 { 1524 struct kvm_nvhe_init_params *params = per_cpu_ptr_nvhe_sym(kvm_init_params, cpu); 1525 unsigned long tcr; 1526 1527 /* 1528 * Calculate the raw per-cpu offset without a translation from the 1529 * kernel's mapping to the linear mapping, and store it in tpidr_el2 1530 * so that we can use adr_l to access per-cpu variables in EL2. 1531 * Also drop the KASAN tag which gets in the way... 1532 */ 1533 params->tpidr_el2 = (unsigned long)kasan_reset_tag(per_cpu_ptr_nvhe_sym(__per_cpu_start, cpu)) - 1534 (unsigned long)kvm_ksym_ref(CHOOSE_NVHE_SYM(__per_cpu_start)); 1535 1536 params->mair_el2 = read_sysreg(mair_el1); 1537 1538 /* 1539 * The ID map may be configured to use an extended virtual address 1540 * range. This is only the case if system RAM is out of range for the 1541 * currently configured page size and VA_BITS, in which case we will 1542 * also need the extended virtual range for the HYP ID map, or we won't 1543 * be able to enable the EL2 MMU. 1544 * 1545 * However, at EL2, there is only one TTBR register, and we can't switch 1546 * between translation tables *and* update TCR_EL2.T0SZ at the same 1547 * time. Bottom line: we need to use the extended range with *both* our 1548 * translation tables. 1549 * 1550 * So use the same T0SZ value we use for the ID map. 1551 */ 1552 tcr = (read_sysreg(tcr_el1) & TCR_EL2_MASK) | TCR_EL2_RES1; 1553 tcr &= ~TCR_T0SZ_MASK; 1554 tcr |= (idmap_t0sz & GENMASK(TCR_TxSZ_WIDTH - 1, 0)) << TCR_T0SZ_OFFSET; 1555 params->tcr_el2 = tcr; 1556 1557 params->pgd_pa = kvm_mmu_get_httbr(); 1558 if (is_protected_kvm_enabled()) 1559 params->hcr_el2 = HCR_HOST_NVHE_PROTECTED_FLAGS; 1560 else 1561 params->hcr_el2 = HCR_HOST_NVHE_FLAGS; 1562 params->vttbr = params->vtcr = 0; 1563 1564 /* 1565 * Flush the init params from the data cache because the struct will 1566 * be read while the MMU is off. 1567 */ 1568 kvm_flush_dcache_to_poc(params, sizeof(*params)); 1569 } 1570 1571 static void hyp_install_host_vector(void) 1572 { 1573 struct kvm_nvhe_init_params *params; 1574 struct arm_smccc_res res; 1575 1576 /* Switch from the HYP stub to our own HYP init vector */ 1577 __hyp_set_vectors(kvm_get_idmap_vector()); 1578 1579 /* 1580 * Call initialization code, and switch to the full blown HYP code. 1581 * If the cpucaps haven't been finalized yet, something has gone very 1582 * wrong, and hyp will crash and burn when it uses any 1583 * cpus_have_const_cap() wrapper. 1584 */ 1585 BUG_ON(!system_capabilities_finalized()); 1586 params = this_cpu_ptr_nvhe_sym(kvm_init_params); 1587 arm_smccc_1_1_hvc(KVM_HOST_SMCCC_FUNC(__kvm_hyp_init), virt_to_phys(params), &res); 1588 WARN_ON(res.a0 != SMCCC_RET_SUCCESS); 1589 } 1590 1591 static void cpu_init_hyp_mode(void) 1592 { 1593 hyp_install_host_vector(); 1594 1595 /* 1596 * Disabling SSBD on a non-VHE system requires us to enable SSBS 1597 * at EL2. 1598 */ 1599 if (this_cpu_has_cap(ARM64_SSBS) && 1600 arm64_get_spectre_v4_state() == SPECTRE_VULNERABLE) { 1601 kvm_call_hyp_nvhe(__kvm_enable_ssbs); 1602 } 1603 } 1604 1605 static void cpu_hyp_reset(void) 1606 { 1607 if (!is_kernel_in_hyp_mode()) 1608 __hyp_reset_vectors(); 1609 } 1610 1611 /* 1612 * EL2 vectors can be mapped and rerouted in a number of ways, 1613 * depending on the kernel configuration and CPU present: 1614 * 1615 * - If the CPU is affected by Spectre-v2, the hardening sequence is 1616 * placed in one of the vector slots, which is executed before jumping 1617 * to the real vectors. 1618 * 1619 * - If the CPU also has the ARM64_SPECTRE_V3A cap, the slot 1620 * containing the hardening sequence is mapped next to the idmap page, 1621 * and executed before jumping to the real vectors. 1622 * 1623 * - If the CPU only has the ARM64_SPECTRE_V3A cap, then an 1624 * empty slot is selected, mapped next to the idmap page, and 1625 * executed before jumping to the real vectors. 1626 * 1627 * Note that ARM64_SPECTRE_V3A is somewhat incompatible with 1628 * VHE, as we don't have hypervisor-specific mappings. If the system 1629 * is VHE and yet selects this capability, it will be ignored. 1630 */ 1631 static void cpu_set_hyp_vector(void) 1632 { 1633 struct bp_hardening_data *data = this_cpu_ptr(&bp_hardening_data); 1634 void *vector = hyp_spectre_vector_selector[data->slot]; 1635 1636 if (!is_protected_kvm_enabled()) 1637 *this_cpu_ptr_hyp_sym(kvm_hyp_vector) = (unsigned long)vector; 1638 else 1639 kvm_call_hyp_nvhe(__pkvm_cpu_set_vector, data->slot); 1640 } 1641 1642 static void cpu_hyp_init_context(void) 1643 { 1644 kvm_init_host_cpu_context(&this_cpu_ptr_hyp_sym(kvm_host_data)->host_ctxt); 1645 1646 if (!is_kernel_in_hyp_mode()) 1647 cpu_init_hyp_mode(); 1648 } 1649 1650 static void cpu_hyp_init_features(void) 1651 { 1652 cpu_set_hyp_vector(); 1653 kvm_arm_init_debug(); 1654 1655 if (is_kernel_in_hyp_mode()) 1656 kvm_timer_init_vhe(); 1657 1658 if (vgic_present) 1659 kvm_vgic_init_cpu_hardware(); 1660 } 1661 1662 static void cpu_hyp_reinit(void) 1663 { 1664 cpu_hyp_reset(); 1665 cpu_hyp_init_context(); 1666 cpu_hyp_init_features(); 1667 } 1668 1669 static void _kvm_arch_hardware_enable(void *discard) 1670 { 1671 if (!__this_cpu_read(kvm_arm_hardware_enabled)) { 1672 cpu_hyp_reinit(); 1673 __this_cpu_write(kvm_arm_hardware_enabled, 1); 1674 } 1675 } 1676 1677 int kvm_arch_hardware_enable(void) 1678 { 1679 _kvm_arch_hardware_enable(NULL); 1680 return 0; 1681 } 1682 1683 static void _kvm_arch_hardware_disable(void *discard) 1684 { 1685 if (__this_cpu_read(kvm_arm_hardware_enabled)) { 1686 cpu_hyp_reset(); 1687 __this_cpu_write(kvm_arm_hardware_enabled, 0); 1688 } 1689 } 1690 1691 void kvm_arch_hardware_disable(void) 1692 { 1693 if (!is_protected_kvm_enabled()) 1694 _kvm_arch_hardware_disable(NULL); 1695 } 1696 1697 #ifdef CONFIG_CPU_PM 1698 static int hyp_init_cpu_pm_notifier(struct notifier_block *self, 1699 unsigned long cmd, 1700 void *v) 1701 { 1702 /* 1703 * kvm_arm_hardware_enabled is left with its old value over 1704 * PM_ENTER->PM_EXIT. It is used to indicate PM_EXIT should 1705 * re-enable hyp. 1706 */ 1707 switch (cmd) { 1708 case CPU_PM_ENTER: 1709 if (__this_cpu_read(kvm_arm_hardware_enabled)) 1710 /* 1711 * don't update kvm_arm_hardware_enabled here 1712 * so that the hardware will be re-enabled 1713 * when we resume. See below. 1714 */ 1715 cpu_hyp_reset(); 1716 1717 return NOTIFY_OK; 1718 case CPU_PM_ENTER_FAILED: 1719 case CPU_PM_EXIT: 1720 if (__this_cpu_read(kvm_arm_hardware_enabled)) 1721 /* The hardware was enabled before suspend. */ 1722 cpu_hyp_reinit(); 1723 1724 return NOTIFY_OK; 1725 1726 default: 1727 return NOTIFY_DONE; 1728 } 1729 } 1730 1731 static struct notifier_block hyp_init_cpu_pm_nb = { 1732 .notifier_call = hyp_init_cpu_pm_notifier, 1733 }; 1734 1735 static void hyp_cpu_pm_init(void) 1736 { 1737 if (!is_protected_kvm_enabled()) 1738 cpu_pm_register_notifier(&hyp_init_cpu_pm_nb); 1739 } 1740 static void hyp_cpu_pm_exit(void) 1741 { 1742 if (!is_protected_kvm_enabled()) 1743 cpu_pm_unregister_notifier(&hyp_init_cpu_pm_nb); 1744 } 1745 #else 1746 static inline void hyp_cpu_pm_init(void) 1747 { 1748 } 1749 static inline void hyp_cpu_pm_exit(void) 1750 { 1751 } 1752 #endif 1753 1754 static void init_cpu_logical_map(void) 1755 { 1756 unsigned int cpu; 1757 1758 /* 1759 * Copy the MPIDR <-> logical CPU ID mapping to hyp. 1760 * Only copy the set of online CPUs whose features have been checked 1761 * against the finalized system capabilities. The hypervisor will not 1762 * allow any other CPUs from the `possible` set to boot. 1763 */ 1764 for_each_online_cpu(cpu) 1765 hyp_cpu_logical_map[cpu] = cpu_logical_map(cpu); 1766 } 1767 1768 #define init_psci_0_1_impl_state(config, what) \ 1769 config.psci_0_1_ ## what ## _implemented = psci_ops.what 1770 1771 static bool init_psci_relay(void) 1772 { 1773 /* 1774 * If PSCI has not been initialized, protected KVM cannot install 1775 * itself on newly booted CPUs. 1776 */ 1777 if (!psci_ops.get_version) { 1778 kvm_err("Cannot initialize protected mode without PSCI\n"); 1779 return false; 1780 } 1781 1782 kvm_host_psci_config.version = psci_ops.get_version(); 1783 1784 if (kvm_host_psci_config.version == PSCI_VERSION(0, 1)) { 1785 kvm_host_psci_config.function_ids_0_1 = get_psci_0_1_function_ids(); 1786 init_psci_0_1_impl_state(kvm_host_psci_config, cpu_suspend); 1787 init_psci_0_1_impl_state(kvm_host_psci_config, cpu_on); 1788 init_psci_0_1_impl_state(kvm_host_psci_config, cpu_off); 1789 init_psci_0_1_impl_state(kvm_host_psci_config, migrate); 1790 } 1791 return true; 1792 } 1793 1794 static int init_subsystems(void) 1795 { 1796 int err = 0; 1797 1798 /* 1799 * Enable hardware so that subsystem initialisation can access EL2. 1800 */ 1801 on_each_cpu(_kvm_arch_hardware_enable, NULL, 1); 1802 1803 /* 1804 * Register CPU lower-power notifier 1805 */ 1806 hyp_cpu_pm_init(); 1807 1808 /* 1809 * Init HYP view of VGIC 1810 */ 1811 err = kvm_vgic_hyp_init(); 1812 switch (err) { 1813 case 0: 1814 vgic_present = true; 1815 break; 1816 case -ENODEV: 1817 case -ENXIO: 1818 vgic_present = false; 1819 err = 0; 1820 break; 1821 default: 1822 goto out; 1823 } 1824 1825 /* 1826 * Init HYP architected timer support 1827 */ 1828 err = kvm_timer_hyp_init(vgic_present); 1829 if (err) 1830 goto out; 1831 1832 kvm_register_perf_callbacks(NULL); 1833 1834 out: 1835 if (err || !is_protected_kvm_enabled()) 1836 on_each_cpu(_kvm_arch_hardware_disable, NULL, 1); 1837 1838 return err; 1839 } 1840 1841 static void teardown_hyp_mode(void) 1842 { 1843 int cpu; 1844 1845 free_hyp_pgds(); 1846 for_each_possible_cpu(cpu) { 1847 free_page(per_cpu(kvm_arm_hyp_stack_page, cpu)); 1848 free_pages(kvm_arm_hyp_percpu_base[cpu], nvhe_percpu_order()); 1849 } 1850 } 1851 1852 static int do_pkvm_init(u32 hyp_va_bits) 1853 { 1854 void *per_cpu_base = kvm_ksym_ref(kvm_arm_hyp_percpu_base); 1855 int ret; 1856 1857 preempt_disable(); 1858 cpu_hyp_init_context(); 1859 ret = kvm_call_hyp_nvhe(__pkvm_init, hyp_mem_base, hyp_mem_size, 1860 num_possible_cpus(), kern_hyp_va(per_cpu_base), 1861 hyp_va_bits); 1862 cpu_hyp_init_features(); 1863 1864 /* 1865 * The stub hypercalls are now disabled, so set our local flag to 1866 * prevent a later re-init attempt in kvm_arch_hardware_enable(). 1867 */ 1868 __this_cpu_write(kvm_arm_hardware_enabled, 1); 1869 preempt_enable(); 1870 1871 return ret; 1872 } 1873 1874 static int kvm_hyp_init_protection(u32 hyp_va_bits) 1875 { 1876 void *addr = phys_to_virt(hyp_mem_base); 1877 int ret; 1878 1879 kvm_nvhe_sym(id_aa64pfr0_el1_sys_val) = read_sanitised_ftr_reg(SYS_ID_AA64PFR0_EL1); 1880 kvm_nvhe_sym(id_aa64pfr1_el1_sys_val) = read_sanitised_ftr_reg(SYS_ID_AA64PFR1_EL1); 1881 kvm_nvhe_sym(id_aa64isar0_el1_sys_val) = read_sanitised_ftr_reg(SYS_ID_AA64ISAR0_EL1); 1882 kvm_nvhe_sym(id_aa64isar1_el1_sys_val) = read_sanitised_ftr_reg(SYS_ID_AA64ISAR1_EL1); 1883 kvm_nvhe_sym(id_aa64isar2_el1_sys_val) = read_sanitised_ftr_reg(SYS_ID_AA64ISAR2_EL1); 1884 kvm_nvhe_sym(id_aa64mmfr0_el1_sys_val) = read_sanitised_ftr_reg(SYS_ID_AA64MMFR0_EL1); 1885 kvm_nvhe_sym(id_aa64mmfr1_el1_sys_val) = read_sanitised_ftr_reg(SYS_ID_AA64MMFR1_EL1); 1886 kvm_nvhe_sym(id_aa64mmfr2_el1_sys_val) = read_sanitised_ftr_reg(SYS_ID_AA64MMFR2_EL1); 1887 1888 ret = create_hyp_mappings(addr, addr + hyp_mem_size, PAGE_HYP); 1889 if (ret) 1890 return ret; 1891 1892 ret = do_pkvm_init(hyp_va_bits); 1893 if (ret) 1894 return ret; 1895 1896 free_hyp_pgds(); 1897 1898 return 0; 1899 } 1900 1901 /** 1902 * Inits Hyp-mode on all online CPUs 1903 */ 1904 static int init_hyp_mode(void) 1905 { 1906 u32 hyp_va_bits; 1907 int cpu; 1908 int err = -ENOMEM; 1909 1910 /* 1911 * The protected Hyp-mode cannot be initialized if the memory pool 1912 * allocation has failed. 1913 */ 1914 if (is_protected_kvm_enabled() && !hyp_mem_base) 1915 goto out_err; 1916 1917 /* 1918 * Allocate Hyp PGD and setup Hyp identity mapping 1919 */ 1920 err = kvm_mmu_init(&hyp_va_bits); 1921 if (err) 1922 goto out_err; 1923 1924 /* 1925 * Allocate stack pages for Hypervisor-mode 1926 */ 1927 for_each_possible_cpu(cpu) { 1928 unsigned long stack_page; 1929 1930 stack_page = __get_free_page(GFP_KERNEL); 1931 if (!stack_page) { 1932 err = -ENOMEM; 1933 goto out_err; 1934 } 1935 1936 per_cpu(kvm_arm_hyp_stack_page, cpu) = stack_page; 1937 } 1938 1939 /* 1940 * Allocate and initialize pages for Hypervisor-mode percpu regions. 1941 */ 1942 for_each_possible_cpu(cpu) { 1943 struct page *page; 1944 void *page_addr; 1945 1946 page = alloc_pages(GFP_KERNEL, nvhe_percpu_order()); 1947 if (!page) { 1948 err = -ENOMEM; 1949 goto out_err; 1950 } 1951 1952 page_addr = page_address(page); 1953 memcpy(page_addr, CHOOSE_NVHE_SYM(__per_cpu_start), nvhe_percpu_size()); 1954 kvm_arm_hyp_percpu_base[cpu] = (unsigned long)page_addr; 1955 } 1956 1957 /* 1958 * Map the Hyp-code called directly from the host 1959 */ 1960 err = create_hyp_mappings(kvm_ksym_ref(__hyp_text_start), 1961 kvm_ksym_ref(__hyp_text_end), PAGE_HYP_EXEC); 1962 if (err) { 1963 kvm_err("Cannot map world-switch code\n"); 1964 goto out_err; 1965 } 1966 1967 err = create_hyp_mappings(kvm_ksym_ref(__hyp_rodata_start), 1968 kvm_ksym_ref(__hyp_rodata_end), PAGE_HYP_RO); 1969 if (err) { 1970 kvm_err("Cannot map .hyp.rodata section\n"); 1971 goto out_err; 1972 } 1973 1974 err = create_hyp_mappings(kvm_ksym_ref(__start_rodata), 1975 kvm_ksym_ref(__end_rodata), PAGE_HYP_RO); 1976 if (err) { 1977 kvm_err("Cannot map rodata section\n"); 1978 goto out_err; 1979 } 1980 1981 /* 1982 * .hyp.bss is guaranteed to be placed at the beginning of the .bss 1983 * section thanks to an assertion in the linker script. Map it RW and 1984 * the rest of .bss RO. 1985 */ 1986 err = create_hyp_mappings(kvm_ksym_ref(__hyp_bss_start), 1987 kvm_ksym_ref(__hyp_bss_end), PAGE_HYP); 1988 if (err) { 1989 kvm_err("Cannot map hyp bss section: %d\n", err); 1990 goto out_err; 1991 } 1992 1993 err = create_hyp_mappings(kvm_ksym_ref(__hyp_bss_end), 1994 kvm_ksym_ref(__bss_stop), PAGE_HYP_RO); 1995 if (err) { 1996 kvm_err("Cannot map bss section\n"); 1997 goto out_err; 1998 } 1999 2000 /* 2001 * Map the Hyp stack pages 2002 */ 2003 for_each_possible_cpu(cpu) { 2004 struct kvm_nvhe_init_params *params = per_cpu_ptr_nvhe_sym(kvm_init_params, cpu); 2005 char *stack_page = (char *)per_cpu(kvm_arm_hyp_stack_page, cpu); 2006 unsigned long hyp_addr; 2007 2008 /* 2009 * Allocate a contiguous HYP private VA range for the stack 2010 * and guard page. The allocation is also aligned based on 2011 * the order of its size. 2012 */ 2013 err = hyp_alloc_private_va_range(PAGE_SIZE * 2, &hyp_addr); 2014 if (err) { 2015 kvm_err("Cannot allocate hyp stack guard page\n"); 2016 goto out_err; 2017 } 2018 2019 /* 2020 * Since the stack grows downwards, map the stack to the page 2021 * at the higher address and leave the lower guard page 2022 * unbacked. 2023 * 2024 * Any valid stack address now has the PAGE_SHIFT bit as 1 2025 * and addresses corresponding to the guard page have the 2026 * PAGE_SHIFT bit as 0 - this is used for overflow detection. 2027 */ 2028 err = __create_hyp_mappings(hyp_addr + PAGE_SIZE, PAGE_SIZE, 2029 __pa(stack_page), PAGE_HYP); 2030 if (err) { 2031 kvm_err("Cannot map hyp stack\n"); 2032 goto out_err; 2033 } 2034 2035 /* 2036 * Save the stack PA in nvhe_init_params. This will be needed 2037 * to recreate the stack mapping in protected nVHE mode. 2038 * __hyp_pa() won't do the right thing there, since the stack 2039 * has been mapped in the flexible private VA space. 2040 */ 2041 params->stack_pa = __pa(stack_page); 2042 2043 params->stack_hyp_va = hyp_addr + (2 * PAGE_SIZE); 2044 } 2045 2046 for_each_possible_cpu(cpu) { 2047 char *percpu_begin = (char *)kvm_arm_hyp_percpu_base[cpu]; 2048 char *percpu_end = percpu_begin + nvhe_percpu_size(); 2049 2050 /* Map Hyp percpu pages */ 2051 err = create_hyp_mappings(percpu_begin, percpu_end, PAGE_HYP); 2052 if (err) { 2053 kvm_err("Cannot map hyp percpu region\n"); 2054 goto out_err; 2055 } 2056 2057 /* Prepare the CPU initialization parameters */ 2058 cpu_prepare_hyp_mode(cpu); 2059 } 2060 2061 if (is_protected_kvm_enabled()) { 2062 init_cpu_logical_map(); 2063 2064 if (!init_psci_relay()) { 2065 err = -ENODEV; 2066 goto out_err; 2067 } 2068 } 2069 2070 if (is_protected_kvm_enabled()) { 2071 err = kvm_hyp_init_protection(hyp_va_bits); 2072 if (err) { 2073 kvm_err("Failed to init hyp memory protection\n"); 2074 goto out_err; 2075 } 2076 } 2077 2078 return 0; 2079 2080 out_err: 2081 teardown_hyp_mode(); 2082 kvm_err("error initializing Hyp mode: %d\n", err); 2083 return err; 2084 } 2085 2086 static void _kvm_host_prot_finalize(void *arg) 2087 { 2088 int *err = arg; 2089 2090 if (WARN_ON(kvm_call_hyp_nvhe(__pkvm_prot_finalize))) 2091 WRITE_ONCE(*err, -EINVAL); 2092 } 2093 2094 static int pkvm_drop_host_privileges(void) 2095 { 2096 int ret = 0; 2097 2098 /* 2099 * Flip the static key upfront as that may no longer be possible 2100 * once the host stage 2 is installed. 2101 */ 2102 static_branch_enable(&kvm_protected_mode_initialized); 2103 on_each_cpu(_kvm_host_prot_finalize, &ret, 1); 2104 return ret; 2105 } 2106 2107 static int finalize_hyp_mode(void) 2108 { 2109 if (!is_protected_kvm_enabled()) 2110 return 0; 2111 2112 /* 2113 * Exclude HYP BSS from kmemleak so that it doesn't get peeked 2114 * at, which would end badly once the section is inaccessible. 2115 * None of other sections should ever be introspected. 2116 */ 2117 kmemleak_free_part(__hyp_bss_start, __hyp_bss_end - __hyp_bss_start); 2118 return pkvm_drop_host_privileges(); 2119 } 2120 2121 struct kvm_vcpu *kvm_mpidr_to_vcpu(struct kvm *kvm, unsigned long mpidr) 2122 { 2123 struct kvm_vcpu *vcpu; 2124 unsigned long i; 2125 2126 mpidr &= MPIDR_HWID_BITMASK; 2127 kvm_for_each_vcpu(i, vcpu, kvm) { 2128 if (mpidr == kvm_vcpu_get_mpidr_aff(vcpu)) 2129 return vcpu; 2130 } 2131 return NULL; 2132 } 2133 2134 bool kvm_arch_has_irq_bypass(void) 2135 { 2136 return true; 2137 } 2138 2139 int kvm_arch_irq_bypass_add_producer(struct irq_bypass_consumer *cons, 2140 struct irq_bypass_producer *prod) 2141 { 2142 struct kvm_kernel_irqfd *irqfd = 2143 container_of(cons, struct kvm_kernel_irqfd, consumer); 2144 2145 return kvm_vgic_v4_set_forwarding(irqfd->kvm, prod->irq, 2146 &irqfd->irq_entry); 2147 } 2148 void kvm_arch_irq_bypass_del_producer(struct irq_bypass_consumer *cons, 2149 struct irq_bypass_producer *prod) 2150 { 2151 struct kvm_kernel_irqfd *irqfd = 2152 container_of(cons, struct kvm_kernel_irqfd, consumer); 2153 2154 kvm_vgic_v4_unset_forwarding(irqfd->kvm, prod->irq, 2155 &irqfd->irq_entry); 2156 } 2157 2158 void kvm_arch_irq_bypass_stop(struct irq_bypass_consumer *cons) 2159 { 2160 struct kvm_kernel_irqfd *irqfd = 2161 container_of(cons, struct kvm_kernel_irqfd, consumer); 2162 2163 kvm_arm_halt_guest(irqfd->kvm); 2164 } 2165 2166 void kvm_arch_irq_bypass_start(struct irq_bypass_consumer *cons) 2167 { 2168 struct kvm_kernel_irqfd *irqfd = 2169 container_of(cons, struct kvm_kernel_irqfd, consumer); 2170 2171 kvm_arm_resume_guest(irqfd->kvm); 2172 } 2173 2174 /** 2175 * Initialize Hyp-mode and memory mappings on all CPUs. 2176 */ 2177 int kvm_arch_init(void *opaque) 2178 { 2179 int err; 2180 bool in_hyp_mode; 2181 2182 if (!is_hyp_mode_available()) { 2183 kvm_info("HYP mode not available\n"); 2184 return -ENODEV; 2185 } 2186 2187 if (kvm_get_mode() == KVM_MODE_NONE) { 2188 kvm_info("KVM disabled from command line\n"); 2189 return -ENODEV; 2190 } 2191 2192 err = kvm_sys_reg_table_init(); 2193 if (err) { 2194 kvm_info("Error initializing system register tables"); 2195 return err; 2196 } 2197 2198 in_hyp_mode = is_kernel_in_hyp_mode(); 2199 2200 if (cpus_have_final_cap(ARM64_WORKAROUND_DEVICE_LOAD_ACQUIRE) || 2201 cpus_have_final_cap(ARM64_WORKAROUND_1508412)) 2202 kvm_info("Guests without required CPU erratum workarounds can deadlock system!\n" \ 2203 "Only trusted guests should be used on this system.\n"); 2204 2205 err = kvm_set_ipa_limit(); 2206 if (err) 2207 return err; 2208 2209 err = kvm_arm_init_sve(); 2210 if (err) 2211 return err; 2212 2213 err = kvm_arm_vmid_alloc_init(); 2214 if (err) { 2215 kvm_err("Failed to initialize VMID allocator.\n"); 2216 return err; 2217 } 2218 2219 if (!in_hyp_mode) { 2220 err = init_hyp_mode(); 2221 if (err) 2222 goto out_err; 2223 } 2224 2225 err = kvm_init_vector_slots(); 2226 if (err) { 2227 kvm_err("Cannot initialise vector slots\n"); 2228 goto out_err; 2229 } 2230 2231 err = init_subsystems(); 2232 if (err) 2233 goto out_hyp; 2234 2235 if (!in_hyp_mode) { 2236 err = finalize_hyp_mode(); 2237 if (err) { 2238 kvm_err("Failed to finalize Hyp protection\n"); 2239 goto out_hyp; 2240 } 2241 } 2242 2243 if (is_protected_kvm_enabled()) { 2244 kvm_info("Protected nVHE mode initialized successfully\n"); 2245 } else if (in_hyp_mode) { 2246 kvm_info("VHE mode initialized successfully\n"); 2247 } else { 2248 kvm_info("Hyp mode initialized successfully\n"); 2249 } 2250 2251 return 0; 2252 2253 out_hyp: 2254 hyp_cpu_pm_exit(); 2255 if (!in_hyp_mode) 2256 teardown_hyp_mode(); 2257 out_err: 2258 kvm_arm_vmid_alloc_free(); 2259 return err; 2260 } 2261 2262 /* NOP: Compiling as a module not supported */ 2263 void kvm_arch_exit(void) 2264 { 2265 kvm_unregister_perf_callbacks(); 2266 } 2267 2268 static int __init early_kvm_mode_cfg(char *arg) 2269 { 2270 if (!arg) 2271 return -EINVAL; 2272 2273 if (strcmp(arg, "protected") == 0) { 2274 kvm_mode = KVM_MODE_PROTECTED; 2275 return 0; 2276 } 2277 2278 if (strcmp(arg, "nvhe") == 0 && !WARN_ON(is_kernel_in_hyp_mode())) { 2279 kvm_mode = KVM_MODE_DEFAULT; 2280 return 0; 2281 } 2282 2283 if (strcmp(arg, "none") == 0) { 2284 kvm_mode = KVM_MODE_NONE; 2285 return 0; 2286 } 2287 2288 return -EINVAL; 2289 } 2290 early_param("kvm-arm.mode", early_kvm_mode_cfg); 2291 2292 enum kvm_mode kvm_get_mode(void) 2293 { 2294 return kvm_mode; 2295 } 2296 2297 static int arm_init(void) 2298 { 2299 int rc = kvm_init(NULL, sizeof(struct kvm_vcpu), 0, THIS_MODULE); 2300 return rc; 2301 } 2302 2303 module_init(arm_init); 2304