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 ret = -ENOMEM; 155 goto out_free_stage2_pgd; 156 } 157 cpumask_copy(kvm->arch.supported_cpus, cpu_possible_mask); 158 159 kvm_vgic_early_init(kvm); 160 161 /* The maximum number of VCPUs is limited by the host's GIC model */ 162 kvm->max_vcpus = kvm_arm_default_max_vcpus(); 163 164 set_default_spectre(kvm); 165 kvm_arm_init_hypercalls(kvm); 166 167 return ret; 168 out_free_stage2_pgd: 169 kvm_free_stage2_pgd(&kvm->arch.mmu); 170 return ret; 171 } 172 173 vm_fault_t kvm_arch_vcpu_fault(struct kvm_vcpu *vcpu, struct vm_fault *vmf) 174 { 175 return VM_FAULT_SIGBUS; 176 } 177 178 179 /** 180 * kvm_arch_destroy_vm - destroy the VM data structure 181 * @kvm: pointer to the KVM struct 182 */ 183 void kvm_arch_destroy_vm(struct kvm *kvm) 184 { 185 bitmap_free(kvm->arch.pmu_filter); 186 free_cpumask_var(kvm->arch.supported_cpus); 187 188 kvm_vgic_destroy(kvm); 189 190 kvm_destroy_vcpus(kvm); 191 192 kvm_unshare_hyp(kvm, kvm + 1); 193 } 194 195 int kvm_vm_ioctl_check_extension(struct kvm *kvm, long ext) 196 { 197 int r; 198 switch (ext) { 199 case KVM_CAP_IRQCHIP: 200 r = vgic_present; 201 break; 202 case KVM_CAP_IOEVENTFD: 203 case KVM_CAP_DEVICE_CTRL: 204 case KVM_CAP_USER_MEMORY: 205 case KVM_CAP_SYNC_MMU: 206 case KVM_CAP_DESTROY_MEMORY_REGION_WORKS: 207 case KVM_CAP_ONE_REG: 208 case KVM_CAP_ARM_PSCI: 209 case KVM_CAP_ARM_PSCI_0_2: 210 case KVM_CAP_READONLY_MEM: 211 case KVM_CAP_MP_STATE: 212 case KVM_CAP_IMMEDIATE_EXIT: 213 case KVM_CAP_VCPU_EVENTS: 214 case KVM_CAP_ARM_IRQ_LINE_LAYOUT_2: 215 case KVM_CAP_ARM_NISV_TO_USER: 216 case KVM_CAP_ARM_INJECT_EXT_DABT: 217 case KVM_CAP_SET_GUEST_DEBUG: 218 case KVM_CAP_VCPU_ATTRIBUTES: 219 case KVM_CAP_PTP_KVM: 220 case KVM_CAP_ARM_SYSTEM_SUSPEND: 221 r = 1; 222 break; 223 case KVM_CAP_SET_GUEST_DEBUG2: 224 return KVM_GUESTDBG_VALID_MASK; 225 case KVM_CAP_ARM_SET_DEVICE_ADDR: 226 r = 1; 227 break; 228 case KVM_CAP_NR_VCPUS: 229 /* 230 * ARM64 treats KVM_CAP_NR_CPUS differently from all other 231 * architectures, as it does not always bound it to 232 * KVM_CAP_MAX_VCPUS. It should not matter much because 233 * this is just an advisory value. 234 */ 235 r = min_t(unsigned int, num_online_cpus(), 236 kvm_arm_default_max_vcpus()); 237 break; 238 case KVM_CAP_MAX_VCPUS: 239 case KVM_CAP_MAX_VCPU_ID: 240 if (kvm) 241 r = kvm->max_vcpus; 242 else 243 r = kvm_arm_default_max_vcpus(); 244 break; 245 case KVM_CAP_MSI_DEVID: 246 if (!kvm) 247 r = -EINVAL; 248 else 249 r = kvm->arch.vgic.msis_require_devid; 250 break; 251 case KVM_CAP_ARM_USER_IRQ: 252 /* 253 * 1: EL1_VTIMER, EL1_PTIMER, and PMU. 254 * (bump this number if adding more devices) 255 */ 256 r = 1; 257 break; 258 case KVM_CAP_ARM_MTE: 259 r = system_supports_mte(); 260 break; 261 case KVM_CAP_STEAL_TIME: 262 r = kvm_arm_pvtime_supported(); 263 break; 264 case KVM_CAP_ARM_EL1_32BIT: 265 r = cpus_have_const_cap(ARM64_HAS_32BIT_EL1); 266 break; 267 case KVM_CAP_GUEST_DEBUG_HW_BPS: 268 r = get_num_brps(); 269 break; 270 case KVM_CAP_GUEST_DEBUG_HW_WPS: 271 r = get_num_wrps(); 272 break; 273 case KVM_CAP_ARM_PMU_V3: 274 r = kvm_arm_support_pmu_v3(); 275 break; 276 case KVM_CAP_ARM_INJECT_SERROR_ESR: 277 r = cpus_have_const_cap(ARM64_HAS_RAS_EXTN); 278 break; 279 case KVM_CAP_ARM_VM_IPA_SIZE: 280 r = get_kvm_ipa_limit(); 281 break; 282 case KVM_CAP_ARM_SVE: 283 r = system_supports_sve(); 284 break; 285 case KVM_CAP_ARM_PTRAUTH_ADDRESS: 286 case KVM_CAP_ARM_PTRAUTH_GENERIC: 287 r = system_has_full_ptr_auth(); 288 break; 289 default: 290 r = 0; 291 } 292 293 return r; 294 } 295 296 long kvm_arch_dev_ioctl(struct file *filp, 297 unsigned int ioctl, unsigned long arg) 298 { 299 return -EINVAL; 300 } 301 302 struct kvm *kvm_arch_alloc_vm(void) 303 { 304 size_t sz = sizeof(struct kvm); 305 306 if (!has_vhe()) 307 return kzalloc(sz, GFP_KERNEL_ACCOUNT); 308 309 return __vmalloc(sz, GFP_KERNEL_ACCOUNT | __GFP_HIGHMEM | __GFP_ZERO); 310 } 311 312 int kvm_arch_vcpu_precreate(struct kvm *kvm, unsigned int id) 313 { 314 if (irqchip_in_kernel(kvm) && vgic_initialized(kvm)) 315 return -EBUSY; 316 317 if (id >= kvm->max_vcpus) 318 return -EINVAL; 319 320 return 0; 321 } 322 323 int kvm_arch_vcpu_create(struct kvm_vcpu *vcpu) 324 { 325 int err; 326 327 /* Force users to call KVM_ARM_VCPU_INIT */ 328 vcpu->arch.target = -1; 329 bitmap_zero(vcpu->arch.features, KVM_VCPU_MAX_FEATURES); 330 331 vcpu->arch.mmu_page_cache.gfp_zero = __GFP_ZERO; 332 333 /* Set up the timer */ 334 kvm_timer_vcpu_init(vcpu); 335 336 kvm_pmu_vcpu_init(vcpu); 337 338 kvm_arm_reset_debug_ptr(vcpu); 339 340 kvm_arm_pvtime_vcpu_init(&vcpu->arch); 341 342 vcpu->arch.hw_mmu = &vcpu->kvm->arch.mmu; 343 344 err = kvm_vgic_vcpu_init(vcpu); 345 if (err) 346 return err; 347 348 return kvm_share_hyp(vcpu, vcpu + 1); 349 } 350 351 void kvm_arch_vcpu_postcreate(struct kvm_vcpu *vcpu) 352 { 353 } 354 355 void kvm_arch_vcpu_destroy(struct kvm_vcpu *vcpu) 356 { 357 if (vcpu_has_run_once(vcpu) && unlikely(!irqchip_in_kernel(vcpu->kvm))) 358 static_branch_dec(&userspace_irqchip_in_use); 359 360 kvm_mmu_free_memory_cache(&vcpu->arch.mmu_page_cache); 361 kvm_timer_vcpu_terminate(vcpu); 362 kvm_pmu_vcpu_destroy(vcpu); 363 364 kvm_arm_vcpu_destroy(vcpu); 365 } 366 367 void kvm_arch_vcpu_blocking(struct kvm_vcpu *vcpu) 368 { 369 370 } 371 372 void kvm_arch_vcpu_unblocking(struct kvm_vcpu *vcpu) 373 { 374 375 } 376 377 void kvm_arch_vcpu_load(struct kvm_vcpu *vcpu, int cpu) 378 { 379 struct kvm_s2_mmu *mmu; 380 int *last_ran; 381 382 mmu = vcpu->arch.hw_mmu; 383 last_ran = this_cpu_ptr(mmu->last_vcpu_ran); 384 385 /* 386 * We guarantee that both TLBs and I-cache are private to each 387 * vcpu. If detecting that a vcpu from the same VM has 388 * previously run on the same physical CPU, call into the 389 * hypervisor code to nuke the relevant contexts. 390 * 391 * We might get preempted before the vCPU actually runs, but 392 * over-invalidation doesn't affect correctness. 393 */ 394 if (*last_ran != vcpu->vcpu_id) { 395 kvm_call_hyp(__kvm_flush_cpu_context, mmu); 396 *last_ran = vcpu->vcpu_id; 397 } 398 399 vcpu->cpu = cpu; 400 401 kvm_vgic_load(vcpu); 402 kvm_timer_vcpu_load(vcpu); 403 if (has_vhe()) 404 kvm_vcpu_load_sysregs_vhe(vcpu); 405 kvm_arch_vcpu_load_fp(vcpu); 406 kvm_vcpu_pmu_restore_guest(vcpu); 407 if (kvm_arm_is_pvtime_enabled(&vcpu->arch)) 408 kvm_make_request(KVM_REQ_RECORD_STEAL, vcpu); 409 410 if (single_task_running()) 411 vcpu_clear_wfx_traps(vcpu); 412 else 413 vcpu_set_wfx_traps(vcpu); 414 415 if (vcpu_has_ptrauth(vcpu)) 416 vcpu_ptrauth_disable(vcpu); 417 kvm_arch_vcpu_load_debug_state_flags(vcpu); 418 419 if (!cpumask_test_cpu(smp_processor_id(), vcpu->kvm->arch.supported_cpus)) 420 vcpu_set_on_unsupported_cpu(vcpu); 421 } 422 423 void kvm_arch_vcpu_put(struct kvm_vcpu *vcpu) 424 { 425 kvm_arch_vcpu_put_debug_state_flags(vcpu); 426 kvm_arch_vcpu_put_fp(vcpu); 427 if (has_vhe()) 428 kvm_vcpu_put_sysregs_vhe(vcpu); 429 kvm_timer_vcpu_put(vcpu); 430 kvm_vgic_put(vcpu); 431 kvm_vcpu_pmu_restore_host(vcpu); 432 kvm_arm_vmid_clear_active(); 433 434 vcpu_clear_on_unsupported_cpu(vcpu); 435 vcpu->cpu = -1; 436 } 437 438 void kvm_arm_vcpu_power_off(struct kvm_vcpu *vcpu) 439 { 440 vcpu->arch.mp_state.mp_state = KVM_MP_STATE_STOPPED; 441 kvm_make_request(KVM_REQ_SLEEP, vcpu); 442 kvm_vcpu_kick(vcpu); 443 } 444 445 bool kvm_arm_vcpu_stopped(struct kvm_vcpu *vcpu) 446 { 447 return vcpu->arch.mp_state.mp_state == KVM_MP_STATE_STOPPED; 448 } 449 450 static void kvm_arm_vcpu_suspend(struct kvm_vcpu *vcpu) 451 { 452 vcpu->arch.mp_state.mp_state = KVM_MP_STATE_SUSPENDED; 453 kvm_make_request(KVM_REQ_SUSPEND, vcpu); 454 kvm_vcpu_kick(vcpu); 455 } 456 457 static bool kvm_arm_vcpu_suspended(struct kvm_vcpu *vcpu) 458 { 459 return vcpu->arch.mp_state.mp_state == KVM_MP_STATE_SUSPENDED; 460 } 461 462 int kvm_arch_vcpu_ioctl_get_mpstate(struct kvm_vcpu *vcpu, 463 struct kvm_mp_state *mp_state) 464 { 465 *mp_state = vcpu->arch.mp_state; 466 467 return 0; 468 } 469 470 int kvm_arch_vcpu_ioctl_set_mpstate(struct kvm_vcpu *vcpu, 471 struct kvm_mp_state *mp_state) 472 { 473 int ret = 0; 474 475 switch (mp_state->mp_state) { 476 case KVM_MP_STATE_RUNNABLE: 477 vcpu->arch.mp_state = *mp_state; 478 break; 479 case KVM_MP_STATE_STOPPED: 480 kvm_arm_vcpu_power_off(vcpu); 481 break; 482 case KVM_MP_STATE_SUSPENDED: 483 kvm_arm_vcpu_suspend(vcpu); 484 break; 485 default: 486 ret = -EINVAL; 487 } 488 489 return ret; 490 } 491 492 /** 493 * kvm_arch_vcpu_runnable - determine if the vcpu can be scheduled 494 * @v: The VCPU pointer 495 * 496 * If the guest CPU is not waiting for interrupts or an interrupt line is 497 * asserted, the CPU is by definition runnable. 498 */ 499 int kvm_arch_vcpu_runnable(struct kvm_vcpu *v) 500 { 501 bool irq_lines = *vcpu_hcr(v) & (HCR_VI | HCR_VF); 502 return ((irq_lines || kvm_vgic_vcpu_pending_irq(v)) 503 && !kvm_arm_vcpu_stopped(v) && !v->arch.pause); 504 } 505 506 bool kvm_arch_vcpu_in_kernel(struct kvm_vcpu *vcpu) 507 { 508 return vcpu_mode_priv(vcpu); 509 } 510 511 #ifdef CONFIG_GUEST_PERF_EVENTS 512 unsigned long kvm_arch_vcpu_get_ip(struct kvm_vcpu *vcpu) 513 { 514 return *vcpu_pc(vcpu); 515 } 516 #endif 517 518 static int kvm_vcpu_initialized(struct kvm_vcpu *vcpu) 519 { 520 return vcpu->arch.target >= 0; 521 } 522 523 /* 524 * Handle both the initialisation that is being done when the vcpu is 525 * run for the first time, as well as the updates that must be 526 * performed each time we get a new thread dealing with this vcpu. 527 */ 528 int kvm_arch_vcpu_run_pid_change(struct kvm_vcpu *vcpu) 529 { 530 struct kvm *kvm = vcpu->kvm; 531 int ret; 532 533 if (!kvm_vcpu_initialized(vcpu)) 534 return -ENOEXEC; 535 536 if (!kvm_arm_vcpu_is_finalized(vcpu)) 537 return -EPERM; 538 539 ret = kvm_arch_vcpu_run_map_fp(vcpu); 540 if (ret) 541 return ret; 542 543 if (likely(vcpu_has_run_once(vcpu))) 544 return 0; 545 546 kvm_arm_vcpu_init_debug(vcpu); 547 548 if (likely(irqchip_in_kernel(kvm))) { 549 /* 550 * Map the VGIC hardware resources before running a vcpu the 551 * first time on this VM. 552 */ 553 ret = kvm_vgic_map_resources(kvm); 554 if (ret) 555 return ret; 556 } 557 558 ret = kvm_timer_enable(vcpu); 559 if (ret) 560 return ret; 561 562 ret = kvm_arm_pmu_v3_enable(vcpu); 563 if (ret) 564 return ret; 565 566 if (!irqchip_in_kernel(kvm)) { 567 /* 568 * Tell the rest of the code that there are userspace irqchip 569 * VMs in the wild. 570 */ 571 static_branch_inc(&userspace_irqchip_in_use); 572 } 573 574 /* 575 * Initialize traps for protected VMs. 576 * NOTE: Move to run in EL2 directly, rather than via a hypercall, once 577 * the code is in place for first run initialization at EL2. 578 */ 579 if (kvm_vm_is_protected(kvm)) 580 kvm_call_hyp_nvhe(__pkvm_vcpu_init_traps, vcpu); 581 582 mutex_lock(&kvm->lock); 583 set_bit(KVM_ARCH_FLAG_HAS_RAN_ONCE, &kvm->arch.flags); 584 mutex_unlock(&kvm->lock); 585 586 return ret; 587 } 588 589 bool kvm_arch_intc_initialized(struct kvm *kvm) 590 { 591 return vgic_initialized(kvm); 592 } 593 594 void kvm_arm_halt_guest(struct kvm *kvm) 595 { 596 unsigned long i; 597 struct kvm_vcpu *vcpu; 598 599 kvm_for_each_vcpu(i, vcpu, kvm) 600 vcpu->arch.pause = true; 601 kvm_make_all_cpus_request(kvm, KVM_REQ_SLEEP); 602 } 603 604 void kvm_arm_resume_guest(struct kvm *kvm) 605 { 606 unsigned long i; 607 struct kvm_vcpu *vcpu; 608 609 kvm_for_each_vcpu(i, vcpu, kvm) { 610 vcpu->arch.pause = false; 611 __kvm_vcpu_wake_up(vcpu); 612 } 613 } 614 615 static void kvm_vcpu_sleep(struct kvm_vcpu *vcpu) 616 { 617 struct rcuwait *wait = kvm_arch_vcpu_get_wait(vcpu); 618 619 rcuwait_wait_event(wait, 620 (!kvm_arm_vcpu_stopped(vcpu)) && (!vcpu->arch.pause), 621 TASK_INTERRUPTIBLE); 622 623 if (kvm_arm_vcpu_stopped(vcpu) || vcpu->arch.pause) { 624 /* Awaken to handle a signal, request we sleep again later. */ 625 kvm_make_request(KVM_REQ_SLEEP, vcpu); 626 } 627 628 /* 629 * Make sure we will observe a potential reset request if we've 630 * observed a change to the power state. Pairs with the smp_wmb() in 631 * kvm_psci_vcpu_on(). 632 */ 633 smp_rmb(); 634 } 635 636 /** 637 * kvm_vcpu_wfi - emulate Wait-For-Interrupt behavior 638 * @vcpu: The VCPU pointer 639 * 640 * Suspend execution of a vCPU until a valid wake event is detected, i.e. until 641 * the vCPU is runnable. The vCPU may or may not be scheduled out, depending 642 * on when a wake event arrives, e.g. there may already be a pending wake event. 643 */ 644 void kvm_vcpu_wfi(struct kvm_vcpu *vcpu) 645 { 646 /* 647 * Sync back the state of the GIC CPU interface so that we have 648 * the latest PMR and group enables. This ensures that 649 * kvm_arch_vcpu_runnable has up-to-date data to decide whether 650 * we have pending interrupts, e.g. when determining if the 651 * vCPU should block. 652 * 653 * For the same reason, we want to tell GICv4 that we need 654 * doorbells to be signalled, should an interrupt become pending. 655 */ 656 preempt_disable(); 657 kvm_vgic_vmcr_sync(vcpu); 658 vgic_v4_put(vcpu, true); 659 preempt_enable(); 660 661 kvm_vcpu_halt(vcpu); 662 vcpu->arch.flags &= ~KVM_ARM64_WFIT; 663 kvm_clear_request(KVM_REQ_UNHALT, vcpu); 664 665 preempt_disable(); 666 vgic_v4_load(vcpu); 667 preempt_enable(); 668 } 669 670 static int kvm_vcpu_suspend(struct kvm_vcpu *vcpu) 671 { 672 if (!kvm_arm_vcpu_suspended(vcpu)) 673 return 1; 674 675 kvm_vcpu_wfi(vcpu); 676 677 /* 678 * The suspend state is sticky; we do not leave it until userspace 679 * explicitly marks the vCPU as runnable. Request that we suspend again 680 * later. 681 */ 682 kvm_make_request(KVM_REQ_SUSPEND, vcpu); 683 684 /* 685 * Check to make sure the vCPU is actually runnable. If so, exit to 686 * userspace informing it of the wakeup condition. 687 */ 688 if (kvm_arch_vcpu_runnable(vcpu)) { 689 memset(&vcpu->run->system_event, 0, sizeof(vcpu->run->system_event)); 690 vcpu->run->system_event.type = KVM_SYSTEM_EVENT_WAKEUP; 691 vcpu->run->exit_reason = KVM_EXIT_SYSTEM_EVENT; 692 return 0; 693 } 694 695 /* 696 * Otherwise, we were unblocked to process a different event, such as a 697 * pending signal. Return 1 and allow kvm_arch_vcpu_ioctl_run() to 698 * process the event. 699 */ 700 return 1; 701 } 702 703 /** 704 * check_vcpu_requests - check and handle pending vCPU requests 705 * @vcpu: the VCPU pointer 706 * 707 * Return: 1 if we should enter the guest 708 * 0 if we should exit to userspace 709 * < 0 if we should exit to userspace, where the return value indicates 710 * an error 711 */ 712 static int check_vcpu_requests(struct kvm_vcpu *vcpu) 713 { 714 if (kvm_request_pending(vcpu)) { 715 if (kvm_check_request(KVM_REQ_SLEEP, vcpu)) 716 kvm_vcpu_sleep(vcpu); 717 718 if (kvm_check_request(KVM_REQ_VCPU_RESET, vcpu)) 719 kvm_reset_vcpu(vcpu); 720 721 /* 722 * Clear IRQ_PENDING requests that were made to guarantee 723 * that a VCPU sees new virtual interrupts. 724 */ 725 kvm_check_request(KVM_REQ_IRQ_PENDING, vcpu); 726 727 if (kvm_check_request(KVM_REQ_RECORD_STEAL, vcpu)) 728 kvm_update_stolen_time(vcpu); 729 730 if (kvm_check_request(KVM_REQ_RELOAD_GICv4, vcpu)) { 731 /* The distributor enable bits were changed */ 732 preempt_disable(); 733 vgic_v4_put(vcpu, false); 734 vgic_v4_load(vcpu); 735 preempt_enable(); 736 } 737 738 if (kvm_check_request(KVM_REQ_RELOAD_PMU, vcpu)) 739 kvm_pmu_handle_pmcr(vcpu, 740 __vcpu_sys_reg(vcpu, PMCR_EL0)); 741 742 if (kvm_check_request(KVM_REQ_SUSPEND, vcpu)) 743 return kvm_vcpu_suspend(vcpu); 744 } 745 746 return 1; 747 } 748 749 static bool vcpu_mode_is_bad_32bit(struct kvm_vcpu *vcpu) 750 { 751 if (likely(!vcpu_mode_is_32bit(vcpu))) 752 return false; 753 754 return !system_supports_32bit_el0() || 755 static_branch_unlikely(&arm64_mismatched_32bit_el0); 756 } 757 758 /** 759 * kvm_vcpu_exit_request - returns true if the VCPU should *not* enter the guest 760 * @vcpu: The VCPU pointer 761 * @ret: Pointer to write optional return code 762 * 763 * Returns: true if the VCPU needs to return to a preemptible + interruptible 764 * and skip guest entry. 765 * 766 * This function disambiguates between two different types of exits: exits to a 767 * preemptible + interruptible kernel context and exits to userspace. For an 768 * exit to userspace, this function will write the return code to ret and return 769 * true. For an exit to preemptible + interruptible kernel context (i.e. check 770 * for pending work and re-enter), return true without writing to ret. 771 */ 772 static bool kvm_vcpu_exit_request(struct kvm_vcpu *vcpu, int *ret) 773 { 774 struct kvm_run *run = vcpu->run; 775 776 /* 777 * If we're using a userspace irqchip, then check if we need 778 * to tell a userspace irqchip about timer or PMU level 779 * changes and if so, exit to userspace (the actual level 780 * state gets updated in kvm_timer_update_run and 781 * kvm_pmu_update_run below). 782 */ 783 if (static_branch_unlikely(&userspace_irqchip_in_use)) { 784 if (kvm_timer_should_notify_user(vcpu) || 785 kvm_pmu_should_notify_user(vcpu)) { 786 *ret = -EINTR; 787 run->exit_reason = KVM_EXIT_INTR; 788 return true; 789 } 790 } 791 792 if (unlikely(vcpu_on_unsupported_cpu(vcpu))) { 793 run->exit_reason = KVM_EXIT_FAIL_ENTRY; 794 run->fail_entry.hardware_entry_failure_reason = KVM_EXIT_FAIL_ENTRY_CPU_UNSUPPORTED; 795 run->fail_entry.cpu = smp_processor_id(); 796 *ret = 0; 797 return true; 798 } 799 800 return kvm_request_pending(vcpu) || 801 xfer_to_guest_mode_work_pending(); 802 } 803 804 /* 805 * Actually run the vCPU, entering an RCU extended quiescent state (EQS) while 806 * the vCPU is running. 807 * 808 * This must be noinstr as instrumentation may make use of RCU, and this is not 809 * safe during the EQS. 810 */ 811 static int noinstr kvm_arm_vcpu_enter_exit(struct kvm_vcpu *vcpu) 812 { 813 int ret; 814 815 guest_state_enter_irqoff(); 816 ret = kvm_call_hyp_ret(__kvm_vcpu_run, vcpu); 817 guest_state_exit_irqoff(); 818 819 return ret; 820 } 821 822 /** 823 * kvm_arch_vcpu_ioctl_run - the main VCPU run function to execute guest code 824 * @vcpu: The VCPU pointer 825 * 826 * This function is called through the VCPU_RUN ioctl called from user space. It 827 * will execute VM code in a loop until the time slice for the process is used 828 * or some emulation is needed from user space in which case the function will 829 * return with return value 0 and with the kvm_run structure filled in with the 830 * required data for the requested emulation. 831 */ 832 int kvm_arch_vcpu_ioctl_run(struct kvm_vcpu *vcpu) 833 { 834 struct kvm_run *run = vcpu->run; 835 int ret; 836 837 if (run->exit_reason == KVM_EXIT_MMIO) { 838 ret = kvm_handle_mmio_return(vcpu); 839 if (ret) 840 return ret; 841 } 842 843 vcpu_load(vcpu); 844 845 if (run->immediate_exit) { 846 ret = -EINTR; 847 goto out; 848 } 849 850 kvm_sigset_activate(vcpu); 851 852 ret = 1; 853 run->exit_reason = KVM_EXIT_UNKNOWN; 854 run->flags = 0; 855 while (ret > 0) { 856 /* 857 * Check conditions before entering the guest 858 */ 859 ret = xfer_to_guest_mode_handle_work(vcpu); 860 if (!ret) 861 ret = 1; 862 863 if (ret > 0) 864 ret = check_vcpu_requests(vcpu); 865 866 /* 867 * Preparing the interrupts to be injected also 868 * involves poking the GIC, which must be done in a 869 * non-preemptible context. 870 */ 871 preempt_disable(); 872 873 /* 874 * The VMID allocator only tracks active VMIDs per 875 * physical CPU, and therefore the VMID allocated may not be 876 * preserved on VMID roll-over if the task was preempted, 877 * making a thread's VMID inactive. So we need to call 878 * kvm_arm_vmid_update() in non-premptible context. 879 */ 880 kvm_arm_vmid_update(&vcpu->arch.hw_mmu->vmid); 881 882 kvm_pmu_flush_hwstate(vcpu); 883 884 local_irq_disable(); 885 886 kvm_vgic_flush_hwstate(vcpu); 887 888 kvm_pmu_update_vcpu_events(vcpu); 889 890 /* 891 * Ensure we set mode to IN_GUEST_MODE after we disable 892 * interrupts and before the final VCPU requests check. 893 * See the comment in kvm_vcpu_exiting_guest_mode() and 894 * Documentation/virt/kvm/vcpu-requests.rst 895 */ 896 smp_store_mb(vcpu->mode, IN_GUEST_MODE); 897 898 if (ret <= 0 || kvm_vcpu_exit_request(vcpu, &ret)) { 899 vcpu->mode = OUTSIDE_GUEST_MODE; 900 isb(); /* Ensure work in x_flush_hwstate is committed */ 901 kvm_pmu_sync_hwstate(vcpu); 902 if (static_branch_unlikely(&userspace_irqchip_in_use)) 903 kvm_timer_sync_user(vcpu); 904 kvm_vgic_sync_hwstate(vcpu); 905 local_irq_enable(); 906 preempt_enable(); 907 continue; 908 } 909 910 kvm_arm_setup_debug(vcpu); 911 kvm_arch_vcpu_ctxflush_fp(vcpu); 912 913 /************************************************************** 914 * Enter the guest 915 */ 916 trace_kvm_entry(*vcpu_pc(vcpu)); 917 guest_timing_enter_irqoff(); 918 919 ret = kvm_arm_vcpu_enter_exit(vcpu); 920 921 vcpu->mode = OUTSIDE_GUEST_MODE; 922 vcpu->stat.exits++; 923 /* 924 * Back from guest 925 *************************************************************/ 926 927 kvm_arm_clear_debug(vcpu); 928 929 /* 930 * We must sync the PMU state before the vgic state so 931 * that the vgic can properly sample the updated state of the 932 * interrupt line. 933 */ 934 kvm_pmu_sync_hwstate(vcpu); 935 936 /* 937 * Sync the vgic state before syncing the timer state because 938 * the timer code needs to know if the virtual timer 939 * interrupts are active. 940 */ 941 kvm_vgic_sync_hwstate(vcpu); 942 943 /* 944 * Sync the timer hardware state before enabling interrupts as 945 * we don't want vtimer interrupts to race with syncing the 946 * timer virtual interrupt state. 947 */ 948 if (static_branch_unlikely(&userspace_irqchip_in_use)) 949 kvm_timer_sync_user(vcpu); 950 951 kvm_arch_vcpu_ctxsync_fp(vcpu); 952 953 /* 954 * We must ensure that any pending interrupts are taken before 955 * we exit guest timing so that timer ticks are accounted as 956 * guest time. Transiently unmask interrupts so that any 957 * pending interrupts are taken. 958 * 959 * Per ARM DDI 0487G.b section D1.13.4, an ISB (or other 960 * context synchronization event) is necessary to ensure that 961 * pending interrupts are taken. 962 */ 963 if (ARM_EXCEPTION_CODE(ret) == ARM_EXCEPTION_IRQ) { 964 local_irq_enable(); 965 isb(); 966 local_irq_disable(); 967 } 968 969 guest_timing_exit_irqoff(); 970 971 local_irq_enable(); 972 973 trace_kvm_exit(ret, kvm_vcpu_trap_get_class(vcpu), *vcpu_pc(vcpu)); 974 975 /* Exit types that need handling before we can be preempted */ 976 handle_exit_early(vcpu, ret); 977 978 preempt_enable(); 979 980 /* 981 * The ARMv8 architecture doesn't give the hypervisor 982 * a mechanism to prevent a guest from dropping to AArch32 EL0 983 * if implemented by the CPU. If we spot the guest in such 984 * state and that we decided it wasn't supposed to do so (like 985 * with the asymmetric AArch32 case), return to userspace with 986 * a fatal error. 987 */ 988 if (vcpu_mode_is_bad_32bit(vcpu)) { 989 /* 990 * As we have caught the guest red-handed, decide that 991 * it isn't fit for purpose anymore by making the vcpu 992 * invalid. The VMM can try and fix it by issuing a 993 * KVM_ARM_VCPU_INIT if it really wants to. 994 */ 995 vcpu->arch.target = -1; 996 ret = ARM_EXCEPTION_IL; 997 } 998 999 ret = handle_exit(vcpu, ret); 1000 } 1001 1002 /* Tell userspace about in-kernel device output levels */ 1003 if (unlikely(!irqchip_in_kernel(vcpu->kvm))) { 1004 kvm_timer_update_run(vcpu); 1005 kvm_pmu_update_run(vcpu); 1006 } 1007 1008 kvm_sigset_deactivate(vcpu); 1009 1010 out: 1011 /* 1012 * In the unlikely event that we are returning to userspace 1013 * with pending exceptions or PC adjustment, commit these 1014 * adjustments in order to give userspace a consistent view of 1015 * the vcpu state. Note that this relies on __kvm_adjust_pc() 1016 * being preempt-safe on VHE. 1017 */ 1018 if (unlikely(vcpu->arch.flags & (KVM_ARM64_PENDING_EXCEPTION | 1019 KVM_ARM64_INCREMENT_PC))) 1020 kvm_call_hyp(__kvm_adjust_pc, vcpu); 1021 1022 vcpu_put(vcpu); 1023 return ret; 1024 } 1025 1026 static int vcpu_interrupt_line(struct kvm_vcpu *vcpu, int number, bool level) 1027 { 1028 int bit_index; 1029 bool set; 1030 unsigned long *hcr; 1031 1032 if (number == KVM_ARM_IRQ_CPU_IRQ) 1033 bit_index = __ffs(HCR_VI); 1034 else /* KVM_ARM_IRQ_CPU_FIQ */ 1035 bit_index = __ffs(HCR_VF); 1036 1037 hcr = vcpu_hcr(vcpu); 1038 if (level) 1039 set = test_and_set_bit(bit_index, hcr); 1040 else 1041 set = test_and_clear_bit(bit_index, hcr); 1042 1043 /* 1044 * If we didn't change anything, no need to wake up or kick other CPUs 1045 */ 1046 if (set == level) 1047 return 0; 1048 1049 /* 1050 * The vcpu irq_lines field was updated, wake up sleeping VCPUs and 1051 * trigger a world-switch round on the running physical CPU to set the 1052 * virtual IRQ/FIQ fields in the HCR appropriately. 1053 */ 1054 kvm_make_request(KVM_REQ_IRQ_PENDING, vcpu); 1055 kvm_vcpu_kick(vcpu); 1056 1057 return 0; 1058 } 1059 1060 int kvm_vm_ioctl_irq_line(struct kvm *kvm, struct kvm_irq_level *irq_level, 1061 bool line_status) 1062 { 1063 u32 irq = irq_level->irq; 1064 unsigned int irq_type, vcpu_idx, irq_num; 1065 int nrcpus = atomic_read(&kvm->online_vcpus); 1066 struct kvm_vcpu *vcpu = NULL; 1067 bool level = irq_level->level; 1068 1069 irq_type = (irq >> KVM_ARM_IRQ_TYPE_SHIFT) & KVM_ARM_IRQ_TYPE_MASK; 1070 vcpu_idx = (irq >> KVM_ARM_IRQ_VCPU_SHIFT) & KVM_ARM_IRQ_VCPU_MASK; 1071 vcpu_idx += ((irq >> KVM_ARM_IRQ_VCPU2_SHIFT) & KVM_ARM_IRQ_VCPU2_MASK) * (KVM_ARM_IRQ_VCPU_MASK + 1); 1072 irq_num = (irq >> KVM_ARM_IRQ_NUM_SHIFT) & KVM_ARM_IRQ_NUM_MASK; 1073 1074 trace_kvm_irq_line(irq_type, vcpu_idx, irq_num, irq_level->level); 1075 1076 switch (irq_type) { 1077 case KVM_ARM_IRQ_TYPE_CPU: 1078 if (irqchip_in_kernel(kvm)) 1079 return -ENXIO; 1080 1081 if (vcpu_idx >= nrcpus) 1082 return -EINVAL; 1083 1084 vcpu = kvm_get_vcpu(kvm, vcpu_idx); 1085 if (!vcpu) 1086 return -EINVAL; 1087 1088 if (irq_num > KVM_ARM_IRQ_CPU_FIQ) 1089 return -EINVAL; 1090 1091 return vcpu_interrupt_line(vcpu, irq_num, level); 1092 case KVM_ARM_IRQ_TYPE_PPI: 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 < VGIC_NR_SGIS || irq_num >= VGIC_NR_PRIVATE_IRQS) 1104 return -EINVAL; 1105 1106 return kvm_vgic_inject_irq(kvm, vcpu->vcpu_id, irq_num, level, NULL); 1107 case KVM_ARM_IRQ_TYPE_SPI: 1108 if (!irqchip_in_kernel(kvm)) 1109 return -ENXIO; 1110 1111 if (irq_num < VGIC_NR_PRIVATE_IRQS) 1112 return -EINVAL; 1113 1114 return kvm_vgic_inject_irq(kvm, 0, irq_num, level, NULL); 1115 } 1116 1117 return -EINVAL; 1118 } 1119 1120 static int kvm_vcpu_set_target(struct kvm_vcpu *vcpu, 1121 const struct kvm_vcpu_init *init) 1122 { 1123 unsigned int i, ret; 1124 u32 phys_target = kvm_target_cpu(); 1125 1126 if (init->target != phys_target) 1127 return -EINVAL; 1128 1129 /* 1130 * Secondary and subsequent calls to KVM_ARM_VCPU_INIT must 1131 * use the same target. 1132 */ 1133 if (vcpu->arch.target != -1 && vcpu->arch.target != init->target) 1134 return -EINVAL; 1135 1136 /* -ENOENT for unknown features, -EINVAL for invalid combinations. */ 1137 for (i = 0; i < sizeof(init->features) * 8; i++) { 1138 bool set = (init->features[i / 32] & (1 << (i % 32))); 1139 1140 if (set && i >= KVM_VCPU_MAX_FEATURES) 1141 return -ENOENT; 1142 1143 /* 1144 * Secondary and subsequent calls to KVM_ARM_VCPU_INIT must 1145 * use the same feature set. 1146 */ 1147 if (vcpu->arch.target != -1 && i < KVM_VCPU_MAX_FEATURES && 1148 test_bit(i, vcpu->arch.features) != set) 1149 return -EINVAL; 1150 1151 if (set) 1152 set_bit(i, vcpu->arch.features); 1153 } 1154 1155 vcpu->arch.target = phys_target; 1156 1157 /* Now we know what it is, we can reset it. */ 1158 ret = kvm_reset_vcpu(vcpu); 1159 if (ret) { 1160 vcpu->arch.target = -1; 1161 bitmap_zero(vcpu->arch.features, KVM_VCPU_MAX_FEATURES); 1162 } 1163 1164 return ret; 1165 } 1166 1167 static int kvm_arch_vcpu_ioctl_vcpu_init(struct kvm_vcpu *vcpu, 1168 struct kvm_vcpu_init *init) 1169 { 1170 int ret; 1171 1172 ret = kvm_vcpu_set_target(vcpu, init); 1173 if (ret) 1174 return ret; 1175 1176 /* 1177 * Ensure a rebooted VM will fault in RAM pages and detect if the 1178 * guest MMU is turned off and flush the caches as needed. 1179 * 1180 * S2FWB enforces all memory accesses to RAM being cacheable, 1181 * ensuring that the data side is always coherent. We still 1182 * need to invalidate the I-cache though, as FWB does *not* 1183 * imply CTR_EL0.DIC. 1184 */ 1185 if (vcpu_has_run_once(vcpu)) { 1186 if (!cpus_have_final_cap(ARM64_HAS_STAGE2_FWB)) 1187 stage2_unmap_vm(vcpu->kvm); 1188 else 1189 icache_inval_all_pou(); 1190 } 1191 1192 vcpu_reset_hcr(vcpu); 1193 vcpu->arch.cptr_el2 = CPTR_EL2_DEFAULT; 1194 1195 /* 1196 * Handle the "start in power-off" case. 1197 */ 1198 if (test_bit(KVM_ARM_VCPU_POWER_OFF, vcpu->arch.features)) 1199 kvm_arm_vcpu_power_off(vcpu); 1200 else 1201 vcpu->arch.mp_state.mp_state = KVM_MP_STATE_RUNNABLE; 1202 1203 return 0; 1204 } 1205 1206 static int kvm_arm_vcpu_set_attr(struct kvm_vcpu *vcpu, 1207 struct kvm_device_attr *attr) 1208 { 1209 int ret = -ENXIO; 1210 1211 switch (attr->group) { 1212 default: 1213 ret = kvm_arm_vcpu_arch_set_attr(vcpu, attr); 1214 break; 1215 } 1216 1217 return ret; 1218 } 1219 1220 static int kvm_arm_vcpu_get_attr(struct kvm_vcpu *vcpu, 1221 struct kvm_device_attr *attr) 1222 { 1223 int ret = -ENXIO; 1224 1225 switch (attr->group) { 1226 default: 1227 ret = kvm_arm_vcpu_arch_get_attr(vcpu, attr); 1228 break; 1229 } 1230 1231 return ret; 1232 } 1233 1234 static int kvm_arm_vcpu_has_attr(struct kvm_vcpu *vcpu, 1235 struct kvm_device_attr *attr) 1236 { 1237 int ret = -ENXIO; 1238 1239 switch (attr->group) { 1240 default: 1241 ret = kvm_arm_vcpu_arch_has_attr(vcpu, attr); 1242 break; 1243 } 1244 1245 return ret; 1246 } 1247 1248 static int kvm_arm_vcpu_get_events(struct kvm_vcpu *vcpu, 1249 struct kvm_vcpu_events *events) 1250 { 1251 memset(events, 0, sizeof(*events)); 1252 1253 return __kvm_arm_vcpu_get_events(vcpu, events); 1254 } 1255 1256 static int kvm_arm_vcpu_set_events(struct kvm_vcpu *vcpu, 1257 struct kvm_vcpu_events *events) 1258 { 1259 int i; 1260 1261 /* check whether the reserved field is zero */ 1262 for (i = 0; i < ARRAY_SIZE(events->reserved); i++) 1263 if (events->reserved[i]) 1264 return -EINVAL; 1265 1266 /* check whether the pad field is zero */ 1267 for (i = 0; i < ARRAY_SIZE(events->exception.pad); i++) 1268 if (events->exception.pad[i]) 1269 return -EINVAL; 1270 1271 return __kvm_arm_vcpu_set_events(vcpu, events); 1272 } 1273 1274 long kvm_arch_vcpu_ioctl(struct file *filp, 1275 unsigned int ioctl, unsigned long arg) 1276 { 1277 struct kvm_vcpu *vcpu = filp->private_data; 1278 void __user *argp = (void __user *)arg; 1279 struct kvm_device_attr attr; 1280 long r; 1281 1282 switch (ioctl) { 1283 case KVM_ARM_VCPU_INIT: { 1284 struct kvm_vcpu_init init; 1285 1286 r = -EFAULT; 1287 if (copy_from_user(&init, argp, sizeof(init))) 1288 break; 1289 1290 r = kvm_arch_vcpu_ioctl_vcpu_init(vcpu, &init); 1291 break; 1292 } 1293 case KVM_SET_ONE_REG: 1294 case KVM_GET_ONE_REG: { 1295 struct kvm_one_reg reg; 1296 1297 r = -ENOEXEC; 1298 if (unlikely(!kvm_vcpu_initialized(vcpu))) 1299 break; 1300 1301 r = -EFAULT; 1302 if (copy_from_user(®, argp, sizeof(reg))) 1303 break; 1304 1305 /* 1306 * We could owe a reset due to PSCI. Handle the pending reset 1307 * here to ensure userspace register accesses are ordered after 1308 * the reset. 1309 */ 1310 if (kvm_check_request(KVM_REQ_VCPU_RESET, vcpu)) 1311 kvm_reset_vcpu(vcpu); 1312 1313 if (ioctl == KVM_SET_ONE_REG) 1314 r = kvm_arm_set_reg(vcpu, ®); 1315 else 1316 r = kvm_arm_get_reg(vcpu, ®); 1317 break; 1318 } 1319 case KVM_GET_REG_LIST: { 1320 struct kvm_reg_list __user *user_list = argp; 1321 struct kvm_reg_list reg_list; 1322 unsigned n; 1323 1324 r = -ENOEXEC; 1325 if (unlikely(!kvm_vcpu_initialized(vcpu))) 1326 break; 1327 1328 r = -EPERM; 1329 if (!kvm_arm_vcpu_is_finalized(vcpu)) 1330 break; 1331 1332 r = -EFAULT; 1333 if (copy_from_user(®_list, user_list, sizeof(reg_list))) 1334 break; 1335 n = reg_list.n; 1336 reg_list.n = kvm_arm_num_regs(vcpu); 1337 if (copy_to_user(user_list, ®_list, sizeof(reg_list))) 1338 break; 1339 r = -E2BIG; 1340 if (n < reg_list.n) 1341 break; 1342 r = kvm_arm_copy_reg_indices(vcpu, user_list->reg); 1343 break; 1344 } 1345 case KVM_SET_DEVICE_ATTR: { 1346 r = -EFAULT; 1347 if (copy_from_user(&attr, argp, sizeof(attr))) 1348 break; 1349 r = kvm_arm_vcpu_set_attr(vcpu, &attr); 1350 break; 1351 } 1352 case KVM_GET_DEVICE_ATTR: { 1353 r = -EFAULT; 1354 if (copy_from_user(&attr, argp, sizeof(attr))) 1355 break; 1356 r = kvm_arm_vcpu_get_attr(vcpu, &attr); 1357 break; 1358 } 1359 case KVM_HAS_DEVICE_ATTR: { 1360 r = -EFAULT; 1361 if (copy_from_user(&attr, argp, sizeof(attr))) 1362 break; 1363 r = kvm_arm_vcpu_has_attr(vcpu, &attr); 1364 break; 1365 } 1366 case KVM_GET_VCPU_EVENTS: { 1367 struct kvm_vcpu_events events; 1368 1369 if (kvm_arm_vcpu_get_events(vcpu, &events)) 1370 return -EINVAL; 1371 1372 if (copy_to_user(argp, &events, sizeof(events))) 1373 return -EFAULT; 1374 1375 return 0; 1376 } 1377 case KVM_SET_VCPU_EVENTS: { 1378 struct kvm_vcpu_events events; 1379 1380 if (copy_from_user(&events, argp, sizeof(events))) 1381 return -EFAULT; 1382 1383 return kvm_arm_vcpu_set_events(vcpu, &events); 1384 } 1385 case KVM_ARM_VCPU_FINALIZE: { 1386 int what; 1387 1388 if (!kvm_vcpu_initialized(vcpu)) 1389 return -ENOEXEC; 1390 1391 if (get_user(what, (const int __user *)argp)) 1392 return -EFAULT; 1393 1394 return kvm_arm_vcpu_finalize(vcpu, what); 1395 } 1396 default: 1397 r = -EINVAL; 1398 } 1399 1400 return r; 1401 } 1402 1403 void kvm_arch_sync_dirty_log(struct kvm *kvm, struct kvm_memory_slot *memslot) 1404 { 1405 1406 } 1407 1408 void kvm_arch_flush_remote_tlbs_memslot(struct kvm *kvm, 1409 const struct kvm_memory_slot *memslot) 1410 { 1411 kvm_flush_remote_tlbs(kvm); 1412 } 1413 1414 static int kvm_vm_ioctl_set_device_addr(struct kvm *kvm, 1415 struct kvm_arm_device_addr *dev_addr) 1416 { 1417 unsigned long dev_id, type; 1418 1419 dev_id = (dev_addr->id & KVM_ARM_DEVICE_ID_MASK) >> 1420 KVM_ARM_DEVICE_ID_SHIFT; 1421 type = (dev_addr->id & KVM_ARM_DEVICE_TYPE_MASK) >> 1422 KVM_ARM_DEVICE_TYPE_SHIFT; 1423 1424 switch (dev_id) { 1425 case KVM_ARM_DEVICE_VGIC_V2: 1426 if (!vgic_present) 1427 return -ENXIO; 1428 return kvm_vgic_addr(kvm, type, &dev_addr->addr, true); 1429 default: 1430 return -ENODEV; 1431 } 1432 } 1433 1434 long kvm_arch_vm_ioctl(struct file *filp, 1435 unsigned int ioctl, unsigned long arg) 1436 { 1437 struct kvm *kvm = filp->private_data; 1438 void __user *argp = (void __user *)arg; 1439 1440 switch (ioctl) { 1441 case KVM_CREATE_IRQCHIP: { 1442 int ret; 1443 if (!vgic_present) 1444 return -ENXIO; 1445 mutex_lock(&kvm->lock); 1446 ret = kvm_vgic_create(kvm, KVM_DEV_TYPE_ARM_VGIC_V2); 1447 mutex_unlock(&kvm->lock); 1448 return ret; 1449 } 1450 case KVM_ARM_SET_DEVICE_ADDR: { 1451 struct kvm_arm_device_addr dev_addr; 1452 1453 if (copy_from_user(&dev_addr, argp, sizeof(dev_addr))) 1454 return -EFAULT; 1455 return kvm_vm_ioctl_set_device_addr(kvm, &dev_addr); 1456 } 1457 case KVM_ARM_PREFERRED_TARGET: { 1458 struct kvm_vcpu_init init; 1459 1460 kvm_vcpu_preferred_target(&init); 1461 1462 if (copy_to_user(argp, &init, sizeof(init))) 1463 return -EFAULT; 1464 1465 return 0; 1466 } 1467 case KVM_ARM_MTE_COPY_TAGS: { 1468 struct kvm_arm_copy_mte_tags copy_tags; 1469 1470 if (copy_from_user(©_tags, argp, sizeof(copy_tags))) 1471 return -EFAULT; 1472 return kvm_vm_ioctl_mte_copy_tags(kvm, ©_tags); 1473 } 1474 default: 1475 return -EINVAL; 1476 } 1477 } 1478 1479 static unsigned long nvhe_percpu_size(void) 1480 { 1481 return (unsigned long)CHOOSE_NVHE_SYM(__per_cpu_end) - 1482 (unsigned long)CHOOSE_NVHE_SYM(__per_cpu_start); 1483 } 1484 1485 static unsigned long nvhe_percpu_order(void) 1486 { 1487 unsigned long size = nvhe_percpu_size(); 1488 1489 return size ? get_order(size) : 0; 1490 } 1491 1492 /* A lookup table holding the hypervisor VA for each vector slot */ 1493 static void *hyp_spectre_vector_selector[BP_HARDEN_EL2_SLOTS]; 1494 1495 static void kvm_init_vector_slot(void *base, enum arm64_hyp_spectre_vector slot) 1496 { 1497 hyp_spectre_vector_selector[slot] = __kvm_vector_slot2addr(base, slot); 1498 } 1499 1500 static int kvm_init_vector_slots(void) 1501 { 1502 int err; 1503 void *base; 1504 1505 base = kern_hyp_va(kvm_ksym_ref(__kvm_hyp_vector)); 1506 kvm_init_vector_slot(base, HYP_VECTOR_DIRECT); 1507 1508 base = kern_hyp_va(kvm_ksym_ref(__bp_harden_hyp_vecs)); 1509 kvm_init_vector_slot(base, HYP_VECTOR_SPECTRE_DIRECT); 1510 1511 if (kvm_system_needs_idmapped_vectors() && 1512 !is_protected_kvm_enabled()) { 1513 err = create_hyp_exec_mappings(__pa_symbol(__bp_harden_hyp_vecs), 1514 __BP_HARDEN_HYP_VECS_SZ, &base); 1515 if (err) 1516 return err; 1517 } 1518 1519 kvm_init_vector_slot(base, HYP_VECTOR_INDIRECT); 1520 kvm_init_vector_slot(base, HYP_VECTOR_SPECTRE_INDIRECT); 1521 return 0; 1522 } 1523 1524 static void cpu_prepare_hyp_mode(int cpu) 1525 { 1526 struct kvm_nvhe_init_params *params = per_cpu_ptr_nvhe_sym(kvm_init_params, cpu); 1527 unsigned long tcr; 1528 1529 /* 1530 * Calculate the raw per-cpu offset without a translation from the 1531 * kernel's mapping to the linear mapping, and store it in tpidr_el2 1532 * so that we can use adr_l to access per-cpu variables in EL2. 1533 * Also drop the KASAN tag which gets in the way... 1534 */ 1535 params->tpidr_el2 = (unsigned long)kasan_reset_tag(per_cpu_ptr_nvhe_sym(__per_cpu_start, cpu)) - 1536 (unsigned long)kvm_ksym_ref(CHOOSE_NVHE_SYM(__per_cpu_start)); 1537 1538 params->mair_el2 = read_sysreg(mair_el1); 1539 1540 /* 1541 * The ID map may be configured to use an extended virtual address 1542 * range. This is only the case if system RAM is out of range for the 1543 * currently configured page size and VA_BITS, in which case we will 1544 * also need the extended virtual range for the HYP ID map, or we won't 1545 * be able to enable the EL2 MMU. 1546 * 1547 * However, at EL2, there is only one TTBR register, and we can't switch 1548 * between translation tables *and* update TCR_EL2.T0SZ at the same 1549 * time. Bottom line: we need to use the extended range with *both* our 1550 * translation tables. 1551 * 1552 * So use the same T0SZ value we use for the ID map. 1553 */ 1554 tcr = (read_sysreg(tcr_el1) & TCR_EL2_MASK) | TCR_EL2_RES1; 1555 tcr &= ~TCR_T0SZ_MASK; 1556 tcr |= (idmap_t0sz & GENMASK(TCR_TxSZ_WIDTH - 1, 0)) << TCR_T0SZ_OFFSET; 1557 params->tcr_el2 = tcr; 1558 1559 params->pgd_pa = kvm_mmu_get_httbr(); 1560 if (is_protected_kvm_enabled()) 1561 params->hcr_el2 = HCR_HOST_NVHE_PROTECTED_FLAGS; 1562 else 1563 params->hcr_el2 = HCR_HOST_NVHE_FLAGS; 1564 params->vttbr = params->vtcr = 0; 1565 1566 /* 1567 * Flush the init params from the data cache because the struct will 1568 * be read while the MMU is off. 1569 */ 1570 kvm_flush_dcache_to_poc(params, sizeof(*params)); 1571 } 1572 1573 static void hyp_install_host_vector(void) 1574 { 1575 struct kvm_nvhe_init_params *params; 1576 struct arm_smccc_res res; 1577 1578 /* Switch from the HYP stub to our own HYP init vector */ 1579 __hyp_set_vectors(kvm_get_idmap_vector()); 1580 1581 /* 1582 * Call initialization code, and switch to the full blown HYP code. 1583 * If the cpucaps haven't been finalized yet, something has gone very 1584 * wrong, and hyp will crash and burn when it uses any 1585 * cpus_have_const_cap() wrapper. 1586 */ 1587 BUG_ON(!system_capabilities_finalized()); 1588 params = this_cpu_ptr_nvhe_sym(kvm_init_params); 1589 arm_smccc_1_1_hvc(KVM_HOST_SMCCC_FUNC(__kvm_hyp_init), virt_to_phys(params), &res); 1590 WARN_ON(res.a0 != SMCCC_RET_SUCCESS); 1591 } 1592 1593 static void cpu_init_hyp_mode(void) 1594 { 1595 hyp_install_host_vector(); 1596 1597 /* 1598 * Disabling SSBD on a non-VHE system requires us to enable SSBS 1599 * at EL2. 1600 */ 1601 if (this_cpu_has_cap(ARM64_SSBS) && 1602 arm64_get_spectre_v4_state() == SPECTRE_VULNERABLE) { 1603 kvm_call_hyp_nvhe(__kvm_enable_ssbs); 1604 } 1605 } 1606 1607 static void cpu_hyp_reset(void) 1608 { 1609 if (!is_kernel_in_hyp_mode()) 1610 __hyp_reset_vectors(); 1611 } 1612 1613 /* 1614 * EL2 vectors can be mapped and rerouted in a number of ways, 1615 * depending on the kernel configuration and CPU present: 1616 * 1617 * - If the CPU is affected by Spectre-v2, the hardening sequence is 1618 * placed in one of the vector slots, which is executed before jumping 1619 * to the real vectors. 1620 * 1621 * - If the CPU also has the ARM64_SPECTRE_V3A cap, the slot 1622 * containing the hardening sequence is mapped next to the idmap page, 1623 * and executed before jumping to the real vectors. 1624 * 1625 * - If the CPU only has the ARM64_SPECTRE_V3A cap, then an 1626 * empty slot is selected, mapped next to the idmap page, and 1627 * executed before jumping to the real vectors. 1628 * 1629 * Note that ARM64_SPECTRE_V3A is somewhat incompatible with 1630 * VHE, as we don't have hypervisor-specific mappings. If the system 1631 * is VHE and yet selects this capability, it will be ignored. 1632 */ 1633 static void cpu_set_hyp_vector(void) 1634 { 1635 struct bp_hardening_data *data = this_cpu_ptr(&bp_hardening_data); 1636 void *vector = hyp_spectre_vector_selector[data->slot]; 1637 1638 if (!is_protected_kvm_enabled()) 1639 *this_cpu_ptr_hyp_sym(kvm_hyp_vector) = (unsigned long)vector; 1640 else 1641 kvm_call_hyp_nvhe(__pkvm_cpu_set_vector, data->slot); 1642 } 1643 1644 static void cpu_hyp_init_context(void) 1645 { 1646 kvm_init_host_cpu_context(&this_cpu_ptr_hyp_sym(kvm_host_data)->host_ctxt); 1647 1648 if (!is_kernel_in_hyp_mode()) 1649 cpu_init_hyp_mode(); 1650 } 1651 1652 static void cpu_hyp_init_features(void) 1653 { 1654 cpu_set_hyp_vector(); 1655 kvm_arm_init_debug(); 1656 1657 if (is_kernel_in_hyp_mode()) 1658 kvm_timer_init_vhe(); 1659 1660 if (vgic_present) 1661 kvm_vgic_init_cpu_hardware(); 1662 } 1663 1664 static void cpu_hyp_reinit(void) 1665 { 1666 cpu_hyp_reset(); 1667 cpu_hyp_init_context(); 1668 cpu_hyp_init_features(); 1669 } 1670 1671 static void _kvm_arch_hardware_enable(void *discard) 1672 { 1673 if (!__this_cpu_read(kvm_arm_hardware_enabled)) { 1674 cpu_hyp_reinit(); 1675 __this_cpu_write(kvm_arm_hardware_enabled, 1); 1676 } 1677 } 1678 1679 int kvm_arch_hardware_enable(void) 1680 { 1681 _kvm_arch_hardware_enable(NULL); 1682 return 0; 1683 } 1684 1685 static void _kvm_arch_hardware_disable(void *discard) 1686 { 1687 if (__this_cpu_read(kvm_arm_hardware_enabled)) { 1688 cpu_hyp_reset(); 1689 __this_cpu_write(kvm_arm_hardware_enabled, 0); 1690 } 1691 } 1692 1693 void kvm_arch_hardware_disable(void) 1694 { 1695 if (!is_protected_kvm_enabled()) 1696 _kvm_arch_hardware_disable(NULL); 1697 } 1698 1699 #ifdef CONFIG_CPU_PM 1700 static int hyp_init_cpu_pm_notifier(struct notifier_block *self, 1701 unsigned long cmd, 1702 void *v) 1703 { 1704 /* 1705 * kvm_arm_hardware_enabled is left with its old value over 1706 * PM_ENTER->PM_EXIT. It is used to indicate PM_EXIT should 1707 * re-enable hyp. 1708 */ 1709 switch (cmd) { 1710 case CPU_PM_ENTER: 1711 if (__this_cpu_read(kvm_arm_hardware_enabled)) 1712 /* 1713 * don't update kvm_arm_hardware_enabled here 1714 * so that the hardware will be re-enabled 1715 * when we resume. See below. 1716 */ 1717 cpu_hyp_reset(); 1718 1719 return NOTIFY_OK; 1720 case CPU_PM_ENTER_FAILED: 1721 case CPU_PM_EXIT: 1722 if (__this_cpu_read(kvm_arm_hardware_enabled)) 1723 /* The hardware was enabled before suspend. */ 1724 cpu_hyp_reinit(); 1725 1726 return NOTIFY_OK; 1727 1728 default: 1729 return NOTIFY_DONE; 1730 } 1731 } 1732 1733 static struct notifier_block hyp_init_cpu_pm_nb = { 1734 .notifier_call = hyp_init_cpu_pm_notifier, 1735 }; 1736 1737 static void hyp_cpu_pm_init(void) 1738 { 1739 if (!is_protected_kvm_enabled()) 1740 cpu_pm_register_notifier(&hyp_init_cpu_pm_nb); 1741 } 1742 static void hyp_cpu_pm_exit(void) 1743 { 1744 if (!is_protected_kvm_enabled()) 1745 cpu_pm_unregister_notifier(&hyp_init_cpu_pm_nb); 1746 } 1747 #else 1748 static inline void hyp_cpu_pm_init(void) 1749 { 1750 } 1751 static inline void hyp_cpu_pm_exit(void) 1752 { 1753 } 1754 #endif 1755 1756 static void init_cpu_logical_map(void) 1757 { 1758 unsigned int cpu; 1759 1760 /* 1761 * Copy the MPIDR <-> logical CPU ID mapping to hyp. 1762 * Only copy the set of online CPUs whose features have been checked 1763 * against the finalized system capabilities. The hypervisor will not 1764 * allow any other CPUs from the `possible` set to boot. 1765 */ 1766 for_each_online_cpu(cpu) 1767 hyp_cpu_logical_map[cpu] = cpu_logical_map(cpu); 1768 } 1769 1770 #define init_psci_0_1_impl_state(config, what) \ 1771 config.psci_0_1_ ## what ## _implemented = psci_ops.what 1772 1773 static bool init_psci_relay(void) 1774 { 1775 /* 1776 * If PSCI has not been initialized, protected KVM cannot install 1777 * itself on newly booted CPUs. 1778 */ 1779 if (!psci_ops.get_version) { 1780 kvm_err("Cannot initialize protected mode without PSCI\n"); 1781 return false; 1782 } 1783 1784 kvm_host_psci_config.version = psci_ops.get_version(); 1785 1786 if (kvm_host_psci_config.version == PSCI_VERSION(0, 1)) { 1787 kvm_host_psci_config.function_ids_0_1 = get_psci_0_1_function_ids(); 1788 init_psci_0_1_impl_state(kvm_host_psci_config, cpu_suspend); 1789 init_psci_0_1_impl_state(kvm_host_psci_config, cpu_on); 1790 init_psci_0_1_impl_state(kvm_host_psci_config, cpu_off); 1791 init_psci_0_1_impl_state(kvm_host_psci_config, migrate); 1792 } 1793 return true; 1794 } 1795 1796 static int init_subsystems(void) 1797 { 1798 int err = 0; 1799 1800 /* 1801 * Enable hardware so that subsystem initialisation can access EL2. 1802 */ 1803 on_each_cpu(_kvm_arch_hardware_enable, NULL, 1); 1804 1805 /* 1806 * Register CPU lower-power notifier 1807 */ 1808 hyp_cpu_pm_init(); 1809 1810 /* 1811 * Init HYP view of VGIC 1812 */ 1813 err = kvm_vgic_hyp_init(); 1814 switch (err) { 1815 case 0: 1816 vgic_present = true; 1817 break; 1818 case -ENODEV: 1819 case -ENXIO: 1820 vgic_present = false; 1821 err = 0; 1822 break; 1823 default: 1824 goto out; 1825 } 1826 1827 /* 1828 * Init HYP architected timer support 1829 */ 1830 err = kvm_timer_hyp_init(vgic_present); 1831 if (err) 1832 goto out; 1833 1834 kvm_register_perf_callbacks(NULL); 1835 1836 out: 1837 if (err || !is_protected_kvm_enabled()) 1838 on_each_cpu(_kvm_arch_hardware_disable, NULL, 1); 1839 1840 return err; 1841 } 1842 1843 static void teardown_hyp_mode(void) 1844 { 1845 int cpu; 1846 1847 free_hyp_pgds(); 1848 for_each_possible_cpu(cpu) { 1849 free_page(per_cpu(kvm_arm_hyp_stack_page, cpu)); 1850 free_pages(kvm_arm_hyp_percpu_base[cpu], nvhe_percpu_order()); 1851 } 1852 } 1853 1854 static int do_pkvm_init(u32 hyp_va_bits) 1855 { 1856 void *per_cpu_base = kvm_ksym_ref(kvm_arm_hyp_percpu_base); 1857 int ret; 1858 1859 preempt_disable(); 1860 cpu_hyp_init_context(); 1861 ret = kvm_call_hyp_nvhe(__pkvm_init, hyp_mem_base, hyp_mem_size, 1862 num_possible_cpus(), kern_hyp_va(per_cpu_base), 1863 hyp_va_bits); 1864 cpu_hyp_init_features(); 1865 1866 /* 1867 * The stub hypercalls are now disabled, so set our local flag to 1868 * prevent a later re-init attempt in kvm_arch_hardware_enable(). 1869 */ 1870 __this_cpu_write(kvm_arm_hardware_enabled, 1); 1871 preempt_enable(); 1872 1873 return ret; 1874 } 1875 1876 static int kvm_hyp_init_protection(u32 hyp_va_bits) 1877 { 1878 void *addr = phys_to_virt(hyp_mem_base); 1879 int ret; 1880 1881 kvm_nvhe_sym(id_aa64pfr0_el1_sys_val) = read_sanitised_ftr_reg(SYS_ID_AA64PFR0_EL1); 1882 kvm_nvhe_sym(id_aa64pfr1_el1_sys_val) = read_sanitised_ftr_reg(SYS_ID_AA64PFR1_EL1); 1883 kvm_nvhe_sym(id_aa64isar0_el1_sys_val) = read_sanitised_ftr_reg(SYS_ID_AA64ISAR0_EL1); 1884 kvm_nvhe_sym(id_aa64isar1_el1_sys_val) = read_sanitised_ftr_reg(SYS_ID_AA64ISAR1_EL1); 1885 kvm_nvhe_sym(id_aa64isar2_el1_sys_val) = read_sanitised_ftr_reg(SYS_ID_AA64ISAR2_EL1); 1886 kvm_nvhe_sym(id_aa64mmfr0_el1_sys_val) = read_sanitised_ftr_reg(SYS_ID_AA64MMFR0_EL1); 1887 kvm_nvhe_sym(id_aa64mmfr1_el1_sys_val) = read_sanitised_ftr_reg(SYS_ID_AA64MMFR1_EL1); 1888 kvm_nvhe_sym(id_aa64mmfr2_el1_sys_val) = read_sanitised_ftr_reg(SYS_ID_AA64MMFR2_EL1); 1889 1890 ret = create_hyp_mappings(addr, addr + hyp_mem_size, PAGE_HYP); 1891 if (ret) 1892 return ret; 1893 1894 ret = do_pkvm_init(hyp_va_bits); 1895 if (ret) 1896 return ret; 1897 1898 free_hyp_pgds(); 1899 1900 return 0; 1901 } 1902 1903 /** 1904 * Inits Hyp-mode on all online CPUs 1905 */ 1906 static int init_hyp_mode(void) 1907 { 1908 u32 hyp_va_bits; 1909 int cpu; 1910 int err = -ENOMEM; 1911 1912 /* 1913 * The protected Hyp-mode cannot be initialized if the memory pool 1914 * allocation has failed. 1915 */ 1916 if (is_protected_kvm_enabled() && !hyp_mem_base) 1917 goto out_err; 1918 1919 /* 1920 * Allocate Hyp PGD and setup Hyp identity mapping 1921 */ 1922 err = kvm_mmu_init(&hyp_va_bits); 1923 if (err) 1924 goto out_err; 1925 1926 /* 1927 * Allocate stack pages for Hypervisor-mode 1928 */ 1929 for_each_possible_cpu(cpu) { 1930 unsigned long stack_page; 1931 1932 stack_page = __get_free_page(GFP_KERNEL); 1933 if (!stack_page) { 1934 err = -ENOMEM; 1935 goto out_err; 1936 } 1937 1938 per_cpu(kvm_arm_hyp_stack_page, cpu) = stack_page; 1939 } 1940 1941 /* 1942 * Allocate and initialize pages for Hypervisor-mode percpu regions. 1943 */ 1944 for_each_possible_cpu(cpu) { 1945 struct page *page; 1946 void *page_addr; 1947 1948 page = alloc_pages(GFP_KERNEL, nvhe_percpu_order()); 1949 if (!page) { 1950 err = -ENOMEM; 1951 goto out_err; 1952 } 1953 1954 page_addr = page_address(page); 1955 memcpy(page_addr, CHOOSE_NVHE_SYM(__per_cpu_start), nvhe_percpu_size()); 1956 kvm_arm_hyp_percpu_base[cpu] = (unsigned long)page_addr; 1957 } 1958 1959 /* 1960 * Map the Hyp-code called directly from the host 1961 */ 1962 err = create_hyp_mappings(kvm_ksym_ref(__hyp_text_start), 1963 kvm_ksym_ref(__hyp_text_end), PAGE_HYP_EXEC); 1964 if (err) { 1965 kvm_err("Cannot map world-switch code\n"); 1966 goto out_err; 1967 } 1968 1969 err = create_hyp_mappings(kvm_ksym_ref(__hyp_rodata_start), 1970 kvm_ksym_ref(__hyp_rodata_end), PAGE_HYP_RO); 1971 if (err) { 1972 kvm_err("Cannot map .hyp.rodata section\n"); 1973 goto out_err; 1974 } 1975 1976 err = create_hyp_mappings(kvm_ksym_ref(__start_rodata), 1977 kvm_ksym_ref(__end_rodata), PAGE_HYP_RO); 1978 if (err) { 1979 kvm_err("Cannot map rodata section\n"); 1980 goto out_err; 1981 } 1982 1983 /* 1984 * .hyp.bss is guaranteed to be placed at the beginning of the .bss 1985 * section thanks to an assertion in the linker script. Map it RW and 1986 * the rest of .bss RO. 1987 */ 1988 err = create_hyp_mappings(kvm_ksym_ref(__hyp_bss_start), 1989 kvm_ksym_ref(__hyp_bss_end), PAGE_HYP); 1990 if (err) { 1991 kvm_err("Cannot map hyp bss section: %d\n", err); 1992 goto out_err; 1993 } 1994 1995 err = create_hyp_mappings(kvm_ksym_ref(__hyp_bss_end), 1996 kvm_ksym_ref(__bss_stop), PAGE_HYP_RO); 1997 if (err) { 1998 kvm_err("Cannot map bss section\n"); 1999 goto out_err; 2000 } 2001 2002 /* 2003 * Map the Hyp stack pages 2004 */ 2005 for_each_possible_cpu(cpu) { 2006 struct kvm_nvhe_init_params *params = per_cpu_ptr_nvhe_sym(kvm_init_params, cpu); 2007 char *stack_page = (char *)per_cpu(kvm_arm_hyp_stack_page, cpu); 2008 unsigned long hyp_addr; 2009 2010 /* 2011 * Allocate a contiguous HYP private VA range for the stack 2012 * and guard page. The allocation is also aligned based on 2013 * the order of its size. 2014 */ 2015 err = hyp_alloc_private_va_range(PAGE_SIZE * 2, &hyp_addr); 2016 if (err) { 2017 kvm_err("Cannot allocate hyp stack guard page\n"); 2018 goto out_err; 2019 } 2020 2021 /* 2022 * Since the stack grows downwards, map the stack to the page 2023 * at the higher address and leave the lower guard page 2024 * unbacked. 2025 * 2026 * Any valid stack address now has the PAGE_SHIFT bit as 1 2027 * and addresses corresponding to the guard page have the 2028 * PAGE_SHIFT bit as 0 - this is used for overflow detection. 2029 */ 2030 err = __create_hyp_mappings(hyp_addr + PAGE_SIZE, PAGE_SIZE, 2031 __pa(stack_page), PAGE_HYP); 2032 if (err) { 2033 kvm_err("Cannot map hyp stack\n"); 2034 goto out_err; 2035 } 2036 2037 /* 2038 * Save the stack PA in nvhe_init_params. This will be needed 2039 * to recreate the stack mapping in protected nVHE mode. 2040 * __hyp_pa() won't do the right thing there, since the stack 2041 * has been mapped in the flexible private VA space. 2042 */ 2043 params->stack_pa = __pa(stack_page); 2044 2045 params->stack_hyp_va = hyp_addr + (2 * PAGE_SIZE); 2046 } 2047 2048 for_each_possible_cpu(cpu) { 2049 char *percpu_begin = (char *)kvm_arm_hyp_percpu_base[cpu]; 2050 char *percpu_end = percpu_begin + nvhe_percpu_size(); 2051 2052 /* Map Hyp percpu pages */ 2053 err = create_hyp_mappings(percpu_begin, percpu_end, PAGE_HYP); 2054 if (err) { 2055 kvm_err("Cannot map hyp percpu region\n"); 2056 goto out_err; 2057 } 2058 2059 /* Prepare the CPU initialization parameters */ 2060 cpu_prepare_hyp_mode(cpu); 2061 } 2062 2063 if (is_protected_kvm_enabled()) { 2064 init_cpu_logical_map(); 2065 2066 if (!init_psci_relay()) { 2067 err = -ENODEV; 2068 goto out_err; 2069 } 2070 } 2071 2072 if (is_protected_kvm_enabled()) { 2073 err = kvm_hyp_init_protection(hyp_va_bits); 2074 if (err) { 2075 kvm_err("Failed to init hyp memory protection\n"); 2076 goto out_err; 2077 } 2078 } 2079 2080 return 0; 2081 2082 out_err: 2083 teardown_hyp_mode(); 2084 kvm_err("error initializing Hyp mode: %d\n", err); 2085 return err; 2086 } 2087 2088 static void _kvm_host_prot_finalize(void *arg) 2089 { 2090 int *err = arg; 2091 2092 if (WARN_ON(kvm_call_hyp_nvhe(__pkvm_prot_finalize))) 2093 WRITE_ONCE(*err, -EINVAL); 2094 } 2095 2096 static int pkvm_drop_host_privileges(void) 2097 { 2098 int ret = 0; 2099 2100 /* 2101 * Flip the static key upfront as that may no longer be possible 2102 * once the host stage 2 is installed. 2103 */ 2104 static_branch_enable(&kvm_protected_mode_initialized); 2105 on_each_cpu(_kvm_host_prot_finalize, &ret, 1); 2106 return ret; 2107 } 2108 2109 static int finalize_hyp_mode(void) 2110 { 2111 if (!is_protected_kvm_enabled()) 2112 return 0; 2113 2114 /* 2115 * Exclude HYP sections from kmemleak so that they don't get peeked 2116 * at, which would end badly once inaccessible. 2117 */ 2118 kmemleak_free_part(__hyp_bss_start, __hyp_bss_end - __hyp_bss_start); 2119 kmemleak_free_part(__va(hyp_mem_base), hyp_mem_size); 2120 return pkvm_drop_host_privileges(); 2121 } 2122 2123 struct kvm_vcpu *kvm_mpidr_to_vcpu(struct kvm *kvm, unsigned long mpidr) 2124 { 2125 struct kvm_vcpu *vcpu; 2126 unsigned long i; 2127 2128 mpidr &= MPIDR_HWID_BITMASK; 2129 kvm_for_each_vcpu(i, vcpu, kvm) { 2130 if (mpidr == kvm_vcpu_get_mpidr_aff(vcpu)) 2131 return vcpu; 2132 } 2133 return NULL; 2134 } 2135 2136 bool kvm_arch_has_irq_bypass(void) 2137 { 2138 return true; 2139 } 2140 2141 int kvm_arch_irq_bypass_add_producer(struct irq_bypass_consumer *cons, 2142 struct irq_bypass_producer *prod) 2143 { 2144 struct kvm_kernel_irqfd *irqfd = 2145 container_of(cons, struct kvm_kernel_irqfd, consumer); 2146 2147 return kvm_vgic_v4_set_forwarding(irqfd->kvm, prod->irq, 2148 &irqfd->irq_entry); 2149 } 2150 void kvm_arch_irq_bypass_del_producer(struct irq_bypass_consumer *cons, 2151 struct irq_bypass_producer *prod) 2152 { 2153 struct kvm_kernel_irqfd *irqfd = 2154 container_of(cons, struct kvm_kernel_irqfd, consumer); 2155 2156 kvm_vgic_v4_unset_forwarding(irqfd->kvm, prod->irq, 2157 &irqfd->irq_entry); 2158 } 2159 2160 void kvm_arch_irq_bypass_stop(struct irq_bypass_consumer *cons) 2161 { 2162 struct kvm_kernel_irqfd *irqfd = 2163 container_of(cons, struct kvm_kernel_irqfd, consumer); 2164 2165 kvm_arm_halt_guest(irqfd->kvm); 2166 } 2167 2168 void kvm_arch_irq_bypass_start(struct irq_bypass_consumer *cons) 2169 { 2170 struct kvm_kernel_irqfd *irqfd = 2171 container_of(cons, struct kvm_kernel_irqfd, consumer); 2172 2173 kvm_arm_resume_guest(irqfd->kvm); 2174 } 2175 2176 /** 2177 * Initialize Hyp-mode and memory mappings on all CPUs. 2178 */ 2179 int kvm_arch_init(void *opaque) 2180 { 2181 int err; 2182 bool in_hyp_mode; 2183 2184 if (!is_hyp_mode_available()) { 2185 kvm_info("HYP mode not available\n"); 2186 return -ENODEV; 2187 } 2188 2189 if (kvm_get_mode() == KVM_MODE_NONE) { 2190 kvm_info("KVM disabled from command line\n"); 2191 return -ENODEV; 2192 } 2193 2194 err = kvm_sys_reg_table_init(); 2195 if (err) { 2196 kvm_info("Error initializing system register tables"); 2197 return err; 2198 } 2199 2200 in_hyp_mode = is_kernel_in_hyp_mode(); 2201 2202 if (cpus_have_final_cap(ARM64_WORKAROUND_DEVICE_LOAD_ACQUIRE) || 2203 cpus_have_final_cap(ARM64_WORKAROUND_1508412)) 2204 kvm_info("Guests without required CPU erratum workarounds can deadlock system!\n" \ 2205 "Only trusted guests should be used on this system.\n"); 2206 2207 err = kvm_set_ipa_limit(); 2208 if (err) 2209 return err; 2210 2211 err = kvm_arm_init_sve(); 2212 if (err) 2213 return err; 2214 2215 err = kvm_arm_vmid_alloc_init(); 2216 if (err) { 2217 kvm_err("Failed to initialize VMID allocator.\n"); 2218 return err; 2219 } 2220 2221 if (!in_hyp_mode) { 2222 err = init_hyp_mode(); 2223 if (err) 2224 goto out_err; 2225 } 2226 2227 err = kvm_init_vector_slots(); 2228 if (err) { 2229 kvm_err("Cannot initialise vector slots\n"); 2230 goto out_err; 2231 } 2232 2233 err = init_subsystems(); 2234 if (err) 2235 goto out_hyp; 2236 2237 if (!in_hyp_mode) { 2238 err = finalize_hyp_mode(); 2239 if (err) { 2240 kvm_err("Failed to finalize Hyp protection\n"); 2241 goto out_hyp; 2242 } 2243 } 2244 2245 if (is_protected_kvm_enabled()) { 2246 kvm_info("Protected nVHE mode initialized successfully\n"); 2247 } else if (in_hyp_mode) { 2248 kvm_info("VHE mode initialized successfully\n"); 2249 } else { 2250 kvm_info("Hyp mode initialized successfully\n"); 2251 } 2252 2253 return 0; 2254 2255 out_hyp: 2256 hyp_cpu_pm_exit(); 2257 if (!in_hyp_mode) 2258 teardown_hyp_mode(); 2259 out_err: 2260 kvm_arm_vmid_alloc_free(); 2261 return err; 2262 } 2263 2264 /* NOP: Compiling as a module not supported */ 2265 void kvm_arch_exit(void) 2266 { 2267 kvm_unregister_perf_callbacks(); 2268 } 2269 2270 static int __init early_kvm_mode_cfg(char *arg) 2271 { 2272 if (!arg) 2273 return -EINVAL; 2274 2275 if (strcmp(arg, "protected") == 0) { 2276 if (!is_kernel_in_hyp_mode()) 2277 kvm_mode = KVM_MODE_PROTECTED; 2278 else 2279 pr_warn_once("Protected KVM not available with VHE\n"); 2280 2281 return 0; 2282 } 2283 2284 if (strcmp(arg, "nvhe") == 0 && !WARN_ON(is_kernel_in_hyp_mode())) { 2285 kvm_mode = KVM_MODE_DEFAULT; 2286 return 0; 2287 } 2288 2289 if (strcmp(arg, "none") == 0) { 2290 kvm_mode = KVM_MODE_NONE; 2291 return 0; 2292 } 2293 2294 return -EINVAL; 2295 } 2296 early_param("kvm-arm.mode", early_kvm_mode_cfg); 2297 2298 enum kvm_mode kvm_get_mode(void) 2299 { 2300 return kvm_mode; 2301 } 2302 2303 static int arm_init(void) 2304 { 2305 int rc = kvm_init(NULL, sizeof(struct kvm_vcpu), 0, THIS_MODULE); 2306 return rc; 2307 } 2308 2309 module_init(arm_init); 2310