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 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 /* 334 * Default value for the FP state, will be overloaded at load 335 * time if we support FP (pretty likely) 336 */ 337 vcpu->arch.fp_state = FP_STATE_FREE; 338 339 /* Set up the timer */ 340 kvm_timer_vcpu_init(vcpu); 341 342 kvm_pmu_vcpu_init(vcpu); 343 344 kvm_arm_reset_debug_ptr(vcpu); 345 346 kvm_arm_pvtime_vcpu_init(&vcpu->arch); 347 348 vcpu->arch.hw_mmu = &vcpu->kvm->arch.mmu; 349 350 err = kvm_vgic_vcpu_init(vcpu); 351 if (err) 352 return err; 353 354 return kvm_share_hyp(vcpu, vcpu + 1); 355 } 356 357 void kvm_arch_vcpu_postcreate(struct kvm_vcpu *vcpu) 358 { 359 } 360 361 void kvm_arch_vcpu_destroy(struct kvm_vcpu *vcpu) 362 { 363 if (vcpu_has_run_once(vcpu) && unlikely(!irqchip_in_kernel(vcpu->kvm))) 364 static_branch_dec(&userspace_irqchip_in_use); 365 366 kvm_mmu_free_memory_cache(&vcpu->arch.mmu_page_cache); 367 kvm_timer_vcpu_terminate(vcpu); 368 kvm_pmu_vcpu_destroy(vcpu); 369 370 kvm_arm_vcpu_destroy(vcpu); 371 } 372 373 void kvm_arch_vcpu_blocking(struct kvm_vcpu *vcpu) 374 { 375 376 } 377 378 void kvm_arch_vcpu_unblocking(struct kvm_vcpu *vcpu) 379 { 380 381 } 382 383 void kvm_arch_vcpu_load(struct kvm_vcpu *vcpu, int cpu) 384 { 385 struct kvm_s2_mmu *mmu; 386 int *last_ran; 387 388 mmu = vcpu->arch.hw_mmu; 389 last_ran = this_cpu_ptr(mmu->last_vcpu_ran); 390 391 /* 392 * We guarantee that both TLBs and I-cache are private to each 393 * vcpu. If detecting that a vcpu from the same VM has 394 * previously run on the same physical CPU, call into the 395 * hypervisor code to nuke the relevant contexts. 396 * 397 * We might get preempted before the vCPU actually runs, but 398 * over-invalidation doesn't affect correctness. 399 */ 400 if (*last_ran != vcpu->vcpu_id) { 401 kvm_call_hyp(__kvm_flush_cpu_context, mmu); 402 *last_ran = vcpu->vcpu_id; 403 } 404 405 vcpu->cpu = cpu; 406 407 kvm_vgic_load(vcpu); 408 kvm_timer_vcpu_load(vcpu); 409 if (has_vhe()) 410 kvm_vcpu_load_sysregs_vhe(vcpu); 411 kvm_arch_vcpu_load_fp(vcpu); 412 kvm_vcpu_pmu_restore_guest(vcpu); 413 if (kvm_arm_is_pvtime_enabled(&vcpu->arch)) 414 kvm_make_request(KVM_REQ_RECORD_STEAL, vcpu); 415 416 if (single_task_running()) 417 vcpu_clear_wfx_traps(vcpu); 418 else 419 vcpu_set_wfx_traps(vcpu); 420 421 if (vcpu_has_ptrauth(vcpu)) 422 vcpu_ptrauth_disable(vcpu); 423 kvm_arch_vcpu_load_debug_state_flags(vcpu); 424 425 if (!cpumask_test_cpu(smp_processor_id(), vcpu->kvm->arch.supported_cpus)) 426 vcpu_set_on_unsupported_cpu(vcpu); 427 } 428 429 void kvm_arch_vcpu_put(struct kvm_vcpu *vcpu) 430 { 431 kvm_arch_vcpu_put_debug_state_flags(vcpu); 432 kvm_arch_vcpu_put_fp(vcpu); 433 if (has_vhe()) 434 kvm_vcpu_put_sysregs_vhe(vcpu); 435 kvm_timer_vcpu_put(vcpu); 436 kvm_vgic_put(vcpu); 437 kvm_vcpu_pmu_restore_host(vcpu); 438 kvm_arm_vmid_clear_active(); 439 440 vcpu_clear_on_unsupported_cpu(vcpu); 441 vcpu->cpu = -1; 442 } 443 444 void kvm_arm_vcpu_power_off(struct kvm_vcpu *vcpu) 445 { 446 vcpu->arch.mp_state.mp_state = KVM_MP_STATE_STOPPED; 447 kvm_make_request(KVM_REQ_SLEEP, vcpu); 448 kvm_vcpu_kick(vcpu); 449 } 450 451 bool kvm_arm_vcpu_stopped(struct kvm_vcpu *vcpu) 452 { 453 return vcpu->arch.mp_state.mp_state == KVM_MP_STATE_STOPPED; 454 } 455 456 static void kvm_arm_vcpu_suspend(struct kvm_vcpu *vcpu) 457 { 458 vcpu->arch.mp_state.mp_state = KVM_MP_STATE_SUSPENDED; 459 kvm_make_request(KVM_REQ_SUSPEND, vcpu); 460 kvm_vcpu_kick(vcpu); 461 } 462 463 static bool kvm_arm_vcpu_suspended(struct kvm_vcpu *vcpu) 464 { 465 return vcpu->arch.mp_state.mp_state == KVM_MP_STATE_SUSPENDED; 466 } 467 468 int kvm_arch_vcpu_ioctl_get_mpstate(struct kvm_vcpu *vcpu, 469 struct kvm_mp_state *mp_state) 470 { 471 *mp_state = vcpu->arch.mp_state; 472 473 return 0; 474 } 475 476 int kvm_arch_vcpu_ioctl_set_mpstate(struct kvm_vcpu *vcpu, 477 struct kvm_mp_state *mp_state) 478 { 479 int ret = 0; 480 481 switch (mp_state->mp_state) { 482 case KVM_MP_STATE_RUNNABLE: 483 vcpu->arch.mp_state = *mp_state; 484 break; 485 case KVM_MP_STATE_STOPPED: 486 kvm_arm_vcpu_power_off(vcpu); 487 break; 488 case KVM_MP_STATE_SUSPENDED: 489 kvm_arm_vcpu_suspend(vcpu); 490 break; 491 default: 492 ret = -EINVAL; 493 } 494 495 return ret; 496 } 497 498 /** 499 * kvm_arch_vcpu_runnable - determine if the vcpu can be scheduled 500 * @v: The VCPU pointer 501 * 502 * If the guest CPU is not waiting for interrupts or an interrupt line is 503 * asserted, the CPU is by definition runnable. 504 */ 505 int kvm_arch_vcpu_runnable(struct kvm_vcpu *v) 506 { 507 bool irq_lines = *vcpu_hcr(v) & (HCR_VI | HCR_VF); 508 return ((irq_lines || kvm_vgic_vcpu_pending_irq(v)) 509 && !kvm_arm_vcpu_stopped(v) && !v->arch.pause); 510 } 511 512 bool kvm_arch_vcpu_in_kernel(struct kvm_vcpu *vcpu) 513 { 514 return vcpu_mode_priv(vcpu); 515 } 516 517 #ifdef CONFIG_GUEST_PERF_EVENTS 518 unsigned long kvm_arch_vcpu_get_ip(struct kvm_vcpu *vcpu) 519 { 520 return *vcpu_pc(vcpu); 521 } 522 #endif 523 524 static int kvm_vcpu_initialized(struct kvm_vcpu *vcpu) 525 { 526 return vcpu->arch.target >= 0; 527 } 528 529 /* 530 * Handle both the initialisation that is being done when the vcpu is 531 * run for the first time, as well as the updates that must be 532 * performed each time we get a new thread dealing with this vcpu. 533 */ 534 int kvm_arch_vcpu_run_pid_change(struct kvm_vcpu *vcpu) 535 { 536 struct kvm *kvm = vcpu->kvm; 537 int ret; 538 539 if (!kvm_vcpu_initialized(vcpu)) 540 return -ENOEXEC; 541 542 if (!kvm_arm_vcpu_is_finalized(vcpu)) 543 return -EPERM; 544 545 ret = kvm_arch_vcpu_run_map_fp(vcpu); 546 if (ret) 547 return ret; 548 549 if (likely(vcpu_has_run_once(vcpu))) 550 return 0; 551 552 kvm_arm_vcpu_init_debug(vcpu); 553 554 if (likely(irqchip_in_kernel(kvm))) { 555 /* 556 * Map the VGIC hardware resources before running a vcpu the 557 * first time on this VM. 558 */ 559 ret = kvm_vgic_map_resources(kvm); 560 if (ret) 561 return ret; 562 } 563 564 ret = kvm_timer_enable(vcpu); 565 if (ret) 566 return ret; 567 568 ret = kvm_arm_pmu_v3_enable(vcpu); 569 if (ret) 570 return ret; 571 572 if (!irqchip_in_kernel(kvm)) { 573 /* 574 * Tell the rest of the code that there are userspace irqchip 575 * VMs in the wild. 576 */ 577 static_branch_inc(&userspace_irqchip_in_use); 578 } 579 580 /* 581 * Initialize traps for protected VMs. 582 * NOTE: Move to run in EL2 directly, rather than via a hypercall, once 583 * the code is in place for first run initialization at EL2. 584 */ 585 if (kvm_vm_is_protected(kvm)) 586 kvm_call_hyp_nvhe(__pkvm_vcpu_init_traps, vcpu); 587 588 mutex_lock(&kvm->lock); 589 set_bit(KVM_ARCH_FLAG_HAS_RAN_ONCE, &kvm->arch.flags); 590 mutex_unlock(&kvm->lock); 591 592 return ret; 593 } 594 595 bool kvm_arch_intc_initialized(struct kvm *kvm) 596 { 597 return vgic_initialized(kvm); 598 } 599 600 void kvm_arm_halt_guest(struct kvm *kvm) 601 { 602 unsigned long i; 603 struct kvm_vcpu *vcpu; 604 605 kvm_for_each_vcpu(i, vcpu, kvm) 606 vcpu->arch.pause = true; 607 kvm_make_all_cpus_request(kvm, KVM_REQ_SLEEP); 608 } 609 610 void kvm_arm_resume_guest(struct kvm *kvm) 611 { 612 unsigned long i; 613 struct kvm_vcpu *vcpu; 614 615 kvm_for_each_vcpu(i, vcpu, kvm) { 616 vcpu->arch.pause = false; 617 __kvm_vcpu_wake_up(vcpu); 618 } 619 } 620 621 static void kvm_vcpu_sleep(struct kvm_vcpu *vcpu) 622 { 623 struct rcuwait *wait = kvm_arch_vcpu_get_wait(vcpu); 624 625 rcuwait_wait_event(wait, 626 (!kvm_arm_vcpu_stopped(vcpu)) && (!vcpu->arch.pause), 627 TASK_INTERRUPTIBLE); 628 629 if (kvm_arm_vcpu_stopped(vcpu) || vcpu->arch.pause) { 630 /* Awaken to handle a signal, request we sleep again later. */ 631 kvm_make_request(KVM_REQ_SLEEP, vcpu); 632 } 633 634 /* 635 * Make sure we will observe a potential reset request if we've 636 * observed a change to the power state. Pairs with the smp_wmb() in 637 * kvm_psci_vcpu_on(). 638 */ 639 smp_rmb(); 640 } 641 642 /** 643 * kvm_vcpu_wfi - emulate Wait-For-Interrupt behavior 644 * @vcpu: The VCPU pointer 645 * 646 * Suspend execution of a vCPU until a valid wake event is detected, i.e. until 647 * the vCPU is runnable. The vCPU may or may not be scheduled out, depending 648 * on when a wake event arrives, e.g. there may already be a pending wake event. 649 */ 650 void kvm_vcpu_wfi(struct kvm_vcpu *vcpu) 651 { 652 /* 653 * Sync back the state of the GIC CPU interface so that we have 654 * the latest PMR and group enables. This ensures that 655 * kvm_arch_vcpu_runnable has up-to-date data to decide whether 656 * we have pending interrupts, e.g. when determining if the 657 * vCPU should block. 658 * 659 * For the same reason, we want to tell GICv4 that we need 660 * doorbells to be signalled, should an interrupt become pending. 661 */ 662 preempt_disable(); 663 kvm_vgic_vmcr_sync(vcpu); 664 vgic_v4_put(vcpu, true); 665 preempt_enable(); 666 667 kvm_vcpu_halt(vcpu); 668 vcpu_clear_flag(vcpu, IN_WFIT); 669 670 preempt_disable(); 671 vgic_v4_load(vcpu); 672 preempt_enable(); 673 } 674 675 static int kvm_vcpu_suspend(struct kvm_vcpu *vcpu) 676 { 677 if (!kvm_arm_vcpu_suspended(vcpu)) 678 return 1; 679 680 kvm_vcpu_wfi(vcpu); 681 682 /* 683 * The suspend state is sticky; we do not leave it until userspace 684 * explicitly marks the vCPU as runnable. Request that we suspend again 685 * later. 686 */ 687 kvm_make_request(KVM_REQ_SUSPEND, vcpu); 688 689 /* 690 * Check to make sure the vCPU is actually runnable. If so, exit to 691 * userspace informing it of the wakeup condition. 692 */ 693 if (kvm_arch_vcpu_runnable(vcpu)) { 694 memset(&vcpu->run->system_event, 0, sizeof(vcpu->run->system_event)); 695 vcpu->run->system_event.type = KVM_SYSTEM_EVENT_WAKEUP; 696 vcpu->run->exit_reason = KVM_EXIT_SYSTEM_EVENT; 697 return 0; 698 } 699 700 /* 701 * Otherwise, we were unblocked to process a different event, such as a 702 * pending signal. Return 1 and allow kvm_arch_vcpu_ioctl_run() to 703 * process the event. 704 */ 705 return 1; 706 } 707 708 /** 709 * check_vcpu_requests - check and handle pending vCPU requests 710 * @vcpu: the VCPU pointer 711 * 712 * Return: 1 if we should enter the guest 713 * 0 if we should exit to userspace 714 * < 0 if we should exit to userspace, where the return value indicates 715 * an error 716 */ 717 static int check_vcpu_requests(struct kvm_vcpu *vcpu) 718 { 719 if (kvm_request_pending(vcpu)) { 720 if (kvm_check_request(KVM_REQ_SLEEP, vcpu)) 721 kvm_vcpu_sleep(vcpu); 722 723 if (kvm_check_request(KVM_REQ_VCPU_RESET, vcpu)) 724 kvm_reset_vcpu(vcpu); 725 726 /* 727 * Clear IRQ_PENDING requests that were made to guarantee 728 * that a VCPU sees new virtual interrupts. 729 */ 730 kvm_check_request(KVM_REQ_IRQ_PENDING, vcpu); 731 732 if (kvm_check_request(KVM_REQ_RECORD_STEAL, vcpu)) 733 kvm_update_stolen_time(vcpu); 734 735 if (kvm_check_request(KVM_REQ_RELOAD_GICv4, vcpu)) { 736 /* The distributor enable bits were changed */ 737 preempt_disable(); 738 vgic_v4_put(vcpu, false); 739 vgic_v4_load(vcpu); 740 preempt_enable(); 741 } 742 743 if (kvm_check_request(KVM_REQ_RELOAD_PMU, vcpu)) 744 kvm_pmu_handle_pmcr(vcpu, 745 __vcpu_sys_reg(vcpu, PMCR_EL0)); 746 747 if (kvm_check_request(KVM_REQ_SUSPEND, vcpu)) 748 return kvm_vcpu_suspend(vcpu); 749 } 750 751 return 1; 752 } 753 754 static bool vcpu_mode_is_bad_32bit(struct kvm_vcpu *vcpu) 755 { 756 if (likely(!vcpu_mode_is_32bit(vcpu))) 757 return false; 758 759 return !kvm_supports_32bit_el0(); 760 } 761 762 /** 763 * kvm_vcpu_exit_request - returns true if the VCPU should *not* enter the guest 764 * @vcpu: The VCPU pointer 765 * @ret: Pointer to write optional return code 766 * 767 * Returns: true if the VCPU needs to return to a preemptible + interruptible 768 * and skip guest entry. 769 * 770 * This function disambiguates between two different types of exits: exits to a 771 * preemptible + interruptible kernel context and exits to userspace. For an 772 * exit to userspace, this function will write the return code to ret and return 773 * true. For an exit to preemptible + interruptible kernel context (i.e. check 774 * for pending work and re-enter), return true without writing to ret. 775 */ 776 static bool kvm_vcpu_exit_request(struct kvm_vcpu *vcpu, int *ret) 777 { 778 struct kvm_run *run = vcpu->run; 779 780 /* 781 * If we're using a userspace irqchip, then check if we need 782 * to tell a userspace irqchip about timer or PMU level 783 * changes and if so, exit to userspace (the actual level 784 * state gets updated in kvm_timer_update_run and 785 * kvm_pmu_update_run below). 786 */ 787 if (static_branch_unlikely(&userspace_irqchip_in_use)) { 788 if (kvm_timer_should_notify_user(vcpu) || 789 kvm_pmu_should_notify_user(vcpu)) { 790 *ret = -EINTR; 791 run->exit_reason = KVM_EXIT_INTR; 792 return true; 793 } 794 } 795 796 if (unlikely(vcpu_on_unsupported_cpu(vcpu))) { 797 run->exit_reason = KVM_EXIT_FAIL_ENTRY; 798 run->fail_entry.hardware_entry_failure_reason = KVM_EXIT_FAIL_ENTRY_CPU_UNSUPPORTED; 799 run->fail_entry.cpu = smp_processor_id(); 800 *ret = 0; 801 return true; 802 } 803 804 return kvm_request_pending(vcpu) || 805 xfer_to_guest_mode_work_pending(); 806 } 807 808 /* 809 * Actually run the vCPU, entering an RCU extended quiescent state (EQS) while 810 * the vCPU is running. 811 * 812 * This must be noinstr as instrumentation may make use of RCU, and this is not 813 * safe during the EQS. 814 */ 815 static int noinstr kvm_arm_vcpu_enter_exit(struct kvm_vcpu *vcpu) 816 { 817 int ret; 818 819 guest_state_enter_irqoff(); 820 ret = kvm_call_hyp_ret(__kvm_vcpu_run, vcpu); 821 guest_state_exit_irqoff(); 822 823 return ret; 824 } 825 826 /** 827 * kvm_arch_vcpu_ioctl_run - the main VCPU run function to execute guest code 828 * @vcpu: The VCPU pointer 829 * 830 * This function is called through the VCPU_RUN ioctl called from user space. It 831 * will execute VM code in a loop until the time slice for the process is used 832 * or some emulation is needed from user space in which case the function will 833 * return with return value 0 and with the kvm_run structure filled in with the 834 * required data for the requested emulation. 835 */ 836 int kvm_arch_vcpu_ioctl_run(struct kvm_vcpu *vcpu) 837 { 838 struct kvm_run *run = vcpu->run; 839 int ret; 840 841 if (run->exit_reason == KVM_EXIT_MMIO) { 842 ret = kvm_handle_mmio_return(vcpu); 843 if (ret) 844 return ret; 845 } 846 847 vcpu_load(vcpu); 848 849 if (run->immediate_exit) { 850 ret = -EINTR; 851 goto out; 852 } 853 854 kvm_sigset_activate(vcpu); 855 856 ret = 1; 857 run->exit_reason = KVM_EXIT_UNKNOWN; 858 run->flags = 0; 859 while (ret > 0) { 860 /* 861 * Check conditions before entering the guest 862 */ 863 ret = xfer_to_guest_mode_handle_work(vcpu); 864 if (!ret) 865 ret = 1; 866 867 if (ret > 0) 868 ret = check_vcpu_requests(vcpu); 869 870 /* 871 * Preparing the interrupts to be injected also 872 * involves poking the GIC, which must be done in a 873 * non-preemptible context. 874 */ 875 preempt_disable(); 876 877 /* 878 * The VMID allocator only tracks active VMIDs per 879 * physical CPU, and therefore the VMID allocated may not be 880 * preserved on VMID roll-over if the task was preempted, 881 * making a thread's VMID inactive. So we need to call 882 * kvm_arm_vmid_update() in non-premptible context. 883 */ 884 kvm_arm_vmid_update(&vcpu->arch.hw_mmu->vmid); 885 886 kvm_pmu_flush_hwstate(vcpu); 887 888 local_irq_disable(); 889 890 kvm_vgic_flush_hwstate(vcpu); 891 892 kvm_pmu_update_vcpu_events(vcpu); 893 894 /* 895 * Ensure we set mode to IN_GUEST_MODE after we disable 896 * interrupts and before the final VCPU requests check. 897 * See the comment in kvm_vcpu_exiting_guest_mode() and 898 * Documentation/virt/kvm/vcpu-requests.rst 899 */ 900 smp_store_mb(vcpu->mode, IN_GUEST_MODE); 901 902 if (ret <= 0 || kvm_vcpu_exit_request(vcpu, &ret)) { 903 vcpu->mode = OUTSIDE_GUEST_MODE; 904 isb(); /* Ensure work in x_flush_hwstate is committed */ 905 kvm_pmu_sync_hwstate(vcpu); 906 if (static_branch_unlikely(&userspace_irqchip_in_use)) 907 kvm_timer_sync_user(vcpu); 908 kvm_vgic_sync_hwstate(vcpu); 909 local_irq_enable(); 910 preempt_enable(); 911 continue; 912 } 913 914 kvm_arm_setup_debug(vcpu); 915 kvm_arch_vcpu_ctxflush_fp(vcpu); 916 917 /************************************************************** 918 * Enter the guest 919 */ 920 trace_kvm_entry(*vcpu_pc(vcpu)); 921 guest_timing_enter_irqoff(); 922 923 ret = kvm_arm_vcpu_enter_exit(vcpu); 924 925 vcpu->mode = OUTSIDE_GUEST_MODE; 926 vcpu->stat.exits++; 927 /* 928 * Back from guest 929 *************************************************************/ 930 931 kvm_arm_clear_debug(vcpu); 932 933 /* 934 * We must sync the PMU state before the vgic state so 935 * that the vgic can properly sample the updated state of the 936 * interrupt line. 937 */ 938 kvm_pmu_sync_hwstate(vcpu); 939 940 /* 941 * Sync the vgic state before syncing the timer state because 942 * the timer code needs to know if the virtual timer 943 * interrupts are active. 944 */ 945 kvm_vgic_sync_hwstate(vcpu); 946 947 /* 948 * Sync the timer hardware state before enabling interrupts as 949 * we don't want vtimer interrupts to race with syncing the 950 * timer virtual interrupt state. 951 */ 952 if (static_branch_unlikely(&userspace_irqchip_in_use)) 953 kvm_timer_sync_user(vcpu); 954 955 kvm_arch_vcpu_ctxsync_fp(vcpu); 956 957 /* 958 * We must ensure that any pending interrupts are taken before 959 * we exit guest timing so that timer ticks are accounted as 960 * guest time. Transiently unmask interrupts so that any 961 * pending interrupts are taken. 962 * 963 * Per ARM DDI 0487G.b section D1.13.4, an ISB (or other 964 * context synchronization event) is necessary to ensure that 965 * pending interrupts are taken. 966 */ 967 if (ARM_EXCEPTION_CODE(ret) == ARM_EXCEPTION_IRQ) { 968 local_irq_enable(); 969 isb(); 970 local_irq_disable(); 971 } 972 973 guest_timing_exit_irqoff(); 974 975 local_irq_enable(); 976 977 trace_kvm_exit(ret, kvm_vcpu_trap_get_class(vcpu), *vcpu_pc(vcpu)); 978 979 /* Exit types that need handling before we can be preempted */ 980 handle_exit_early(vcpu, ret); 981 982 preempt_enable(); 983 984 /* 985 * The ARMv8 architecture doesn't give the hypervisor 986 * a mechanism to prevent a guest from dropping to AArch32 EL0 987 * if implemented by the CPU. If we spot the guest in such 988 * state and that we decided it wasn't supposed to do so (like 989 * with the asymmetric AArch32 case), return to userspace with 990 * a fatal error. 991 */ 992 if (vcpu_mode_is_bad_32bit(vcpu)) { 993 /* 994 * As we have caught the guest red-handed, decide that 995 * it isn't fit for purpose anymore by making the vcpu 996 * invalid. The VMM can try and fix it by issuing a 997 * KVM_ARM_VCPU_INIT if it really wants to. 998 */ 999 vcpu->arch.target = -1; 1000 ret = ARM_EXCEPTION_IL; 1001 } 1002 1003 ret = handle_exit(vcpu, ret); 1004 } 1005 1006 /* Tell userspace about in-kernel device output levels */ 1007 if (unlikely(!irqchip_in_kernel(vcpu->kvm))) { 1008 kvm_timer_update_run(vcpu); 1009 kvm_pmu_update_run(vcpu); 1010 } 1011 1012 kvm_sigset_deactivate(vcpu); 1013 1014 out: 1015 /* 1016 * In the unlikely event that we are returning to userspace 1017 * with pending exceptions or PC adjustment, commit these 1018 * adjustments in order to give userspace a consistent view of 1019 * the vcpu state. Note that this relies on __kvm_adjust_pc() 1020 * being preempt-safe on VHE. 1021 */ 1022 if (unlikely(vcpu_get_flag(vcpu, PENDING_EXCEPTION) || 1023 vcpu_get_flag(vcpu, INCREMENT_PC))) 1024 kvm_call_hyp(__kvm_adjust_pc, vcpu); 1025 1026 vcpu_put(vcpu); 1027 return ret; 1028 } 1029 1030 static int vcpu_interrupt_line(struct kvm_vcpu *vcpu, int number, bool level) 1031 { 1032 int bit_index; 1033 bool set; 1034 unsigned long *hcr; 1035 1036 if (number == KVM_ARM_IRQ_CPU_IRQ) 1037 bit_index = __ffs(HCR_VI); 1038 else /* KVM_ARM_IRQ_CPU_FIQ */ 1039 bit_index = __ffs(HCR_VF); 1040 1041 hcr = vcpu_hcr(vcpu); 1042 if (level) 1043 set = test_and_set_bit(bit_index, hcr); 1044 else 1045 set = test_and_clear_bit(bit_index, hcr); 1046 1047 /* 1048 * If we didn't change anything, no need to wake up or kick other CPUs 1049 */ 1050 if (set == level) 1051 return 0; 1052 1053 /* 1054 * The vcpu irq_lines field was updated, wake up sleeping VCPUs and 1055 * trigger a world-switch round on the running physical CPU to set the 1056 * virtual IRQ/FIQ fields in the HCR appropriately. 1057 */ 1058 kvm_make_request(KVM_REQ_IRQ_PENDING, vcpu); 1059 kvm_vcpu_kick(vcpu); 1060 1061 return 0; 1062 } 1063 1064 int kvm_vm_ioctl_irq_line(struct kvm *kvm, struct kvm_irq_level *irq_level, 1065 bool line_status) 1066 { 1067 u32 irq = irq_level->irq; 1068 unsigned int irq_type, vcpu_idx, irq_num; 1069 int nrcpus = atomic_read(&kvm->online_vcpus); 1070 struct kvm_vcpu *vcpu = NULL; 1071 bool level = irq_level->level; 1072 1073 irq_type = (irq >> KVM_ARM_IRQ_TYPE_SHIFT) & KVM_ARM_IRQ_TYPE_MASK; 1074 vcpu_idx = (irq >> KVM_ARM_IRQ_VCPU_SHIFT) & KVM_ARM_IRQ_VCPU_MASK; 1075 vcpu_idx += ((irq >> KVM_ARM_IRQ_VCPU2_SHIFT) & KVM_ARM_IRQ_VCPU2_MASK) * (KVM_ARM_IRQ_VCPU_MASK + 1); 1076 irq_num = (irq >> KVM_ARM_IRQ_NUM_SHIFT) & KVM_ARM_IRQ_NUM_MASK; 1077 1078 trace_kvm_irq_line(irq_type, vcpu_idx, irq_num, irq_level->level); 1079 1080 switch (irq_type) { 1081 case KVM_ARM_IRQ_TYPE_CPU: 1082 if (irqchip_in_kernel(kvm)) 1083 return -ENXIO; 1084 1085 if (vcpu_idx >= nrcpus) 1086 return -EINVAL; 1087 1088 vcpu = kvm_get_vcpu(kvm, vcpu_idx); 1089 if (!vcpu) 1090 return -EINVAL; 1091 1092 if (irq_num > KVM_ARM_IRQ_CPU_FIQ) 1093 return -EINVAL; 1094 1095 return vcpu_interrupt_line(vcpu, irq_num, level); 1096 case KVM_ARM_IRQ_TYPE_PPI: 1097 if (!irqchip_in_kernel(kvm)) 1098 return -ENXIO; 1099 1100 if (vcpu_idx >= nrcpus) 1101 return -EINVAL; 1102 1103 vcpu = kvm_get_vcpu(kvm, vcpu_idx); 1104 if (!vcpu) 1105 return -EINVAL; 1106 1107 if (irq_num < VGIC_NR_SGIS || irq_num >= VGIC_NR_PRIVATE_IRQS) 1108 return -EINVAL; 1109 1110 return kvm_vgic_inject_irq(kvm, vcpu->vcpu_id, irq_num, level, NULL); 1111 case KVM_ARM_IRQ_TYPE_SPI: 1112 if (!irqchip_in_kernel(kvm)) 1113 return -ENXIO; 1114 1115 if (irq_num < VGIC_NR_PRIVATE_IRQS) 1116 return -EINVAL; 1117 1118 return kvm_vgic_inject_irq(kvm, 0, irq_num, level, NULL); 1119 } 1120 1121 return -EINVAL; 1122 } 1123 1124 static int kvm_vcpu_set_target(struct kvm_vcpu *vcpu, 1125 const struct kvm_vcpu_init *init) 1126 { 1127 unsigned int i, ret; 1128 u32 phys_target = kvm_target_cpu(); 1129 1130 if (init->target != phys_target) 1131 return -EINVAL; 1132 1133 /* 1134 * Secondary and subsequent calls to KVM_ARM_VCPU_INIT must 1135 * use the same target. 1136 */ 1137 if (vcpu->arch.target != -1 && vcpu->arch.target != init->target) 1138 return -EINVAL; 1139 1140 /* -ENOENT for unknown features, -EINVAL for invalid combinations. */ 1141 for (i = 0; i < sizeof(init->features) * 8; i++) { 1142 bool set = (init->features[i / 32] & (1 << (i % 32))); 1143 1144 if (set && i >= KVM_VCPU_MAX_FEATURES) 1145 return -ENOENT; 1146 1147 /* 1148 * Secondary and subsequent calls to KVM_ARM_VCPU_INIT must 1149 * use the same feature set. 1150 */ 1151 if (vcpu->arch.target != -1 && i < KVM_VCPU_MAX_FEATURES && 1152 test_bit(i, vcpu->arch.features) != set) 1153 return -EINVAL; 1154 1155 if (set) 1156 set_bit(i, vcpu->arch.features); 1157 } 1158 1159 vcpu->arch.target = phys_target; 1160 1161 /* Now we know what it is, we can reset it. */ 1162 ret = kvm_reset_vcpu(vcpu); 1163 if (ret) { 1164 vcpu->arch.target = -1; 1165 bitmap_zero(vcpu->arch.features, KVM_VCPU_MAX_FEATURES); 1166 } 1167 1168 return ret; 1169 } 1170 1171 static int kvm_arch_vcpu_ioctl_vcpu_init(struct kvm_vcpu *vcpu, 1172 struct kvm_vcpu_init *init) 1173 { 1174 int ret; 1175 1176 ret = kvm_vcpu_set_target(vcpu, init); 1177 if (ret) 1178 return ret; 1179 1180 /* 1181 * Ensure a rebooted VM will fault in RAM pages and detect if the 1182 * guest MMU is turned off and flush the caches as needed. 1183 * 1184 * S2FWB enforces all memory accesses to RAM being cacheable, 1185 * ensuring that the data side is always coherent. We still 1186 * need to invalidate the I-cache though, as FWB does *not* 1187 * imply CTR_EL0.DIC. 1188 */ 1189 if (vcpu_has_run_once(vcpu)) { 1190 if (!cpus_have_final_cap(ARM64_HAS_STAGE2_FWB)) 1191 stage2_unmap_vm(vcpu->kvm); 1192 else 1193 icache_inval_all_pou(); 1194 } 1195 1196 vcpu_reset_hcr(vcpu); 1197 vcpu->arch.cptr_el2 = CPTR_EL2_DEFAULT; 1198 1199 /* 1200 * Handle the "start in power-off" case. 1201 */ 1202 if (test_bit(KVM_ARM_VCPU_POWER_OFF, vcpu->arch.features)) 1203 kvm_arm_vcpu_power_off(vcpu); 1204 else 1205 vcpu->arch.mp_state.mp_state = KVM_MP_STATE_RUNNABLE; 1206 1207 return 0; 1208 } 1209 1210 static int kvm_arm_vcpu_set_attr(struct kvm_vcpu *vcpu, 1211 struct kvm_device_attr *attr) 1212 { 1213 int ret = -ENXIO; 1214 1215 switch (attr->group) { 1216 default: 1217 ret = kvm_arm_vcpu_arch_set_attr(vcpu, attr); 1218 break; 1219 } 1220 1221 return ret; 1222 } 1223 1224 static int kvm_arm_vcpu_get_attr(struct kvm_vcpu *vcpu, 1225 struct kvm_device_attr *attr) 1226 { 1227 int ret = -ENXIO; 1228 1229 switch (attr->group) { 1230 default: 1231 ret = kvm_arm_vcpu_arch_get_attr(vcpu, attr); 1232 break; 1233 } 1234 1235 return ret; 1236 } 1237 1238 static int kvm_arm_vcpu_has_attr(struct kvm_vcpu *vcpu, 1239 struct kvm_device_attr *attr) 1240 { 1241 int ret = -ENXIO; 1242 1243 switch (attr->group) { 1244 default: 1245 ret = kvm_arm_vcpu_arch_has_attr(vcpu, attr); 1246 break; 1247 } 1248 1249 return ret; 1250 } 1251 1252 static int kvm_arm_vcpu_get_events(struct kvm_vcpu *vcpu, 1253 struct kvm_vcpu_events *events) 1254 { 1255 memset(events, 0, sizeof(*events)); 1256 1257 return __kvm_arm_vcpu_get_events(vcpu, events); 1258 } 1259 1260 static int kvm_arm_vcpu_set_events(struct kvm_vcpu *vcpu, 1261 struct kvm_vcpu_events *events) 1262 { 1263 int i; 1264 1265 /* check whether the reserved field is zero */ 1266 for (i = 0; i < ARRAY_SIZE(events->reserved); i++) 1267 if (events->reserved[i]) 1268 return -EINVAL; 1269 1270 /* check whether the pad field is zero */ 1271 for (i = 0; i < ARRAY_SIZE(events->exception.pad); i++) 1272 if (events->exception.pad[i]) 1273 return -EINVAL; 1274 1275 return __kvm_arm_vcpu_set_events(vcpu, events); 1276 } 1277 1278 long kvm_arch_vcpu_ioctl(struct file *filp, 1279 unsigned int ioctl, unsigned long arg) 1280 { 1281 struct kvm_vcpu *vcpu = filp->private_data; 1282 void __user *argp = (void __user *)arg; 1283 struct kvm_device_attr attr; 1284 long r; 1285 1286 switch (ioctl) { 1287 case KVM_ARM_VCPU_INIT: { 1288 struct kvm_vcpu_init init; 1289 1290 r = -EFAULT; 1291 if (copy_from_user(&init, argp, sizeof(init))) 1292 break; 1293 1294 r = kvm_arch_vcpu_ioctl_vcpu_init(vcpu, &init); 1295 break; 1296 } 1297 case KVM_SET_ONE_REG: 1298 case KVM_GET_ONE_REG: { 1299 struct kvm_one_reg reg; 1300 1301 r = -ENOEXEC; 1302 if (unlikely(!kvm_vcpu_initialized(vcpu))) 1303 break; 1304 1305 r = -EFAULT; 1306 if (copy_from_user(®, argp, sizeof(reg))) 1307 break; 1308 1309 /* 1310 * We could owe a reset due to PSCI. Handle the pending reset 1311 * here to ensure userspace register accesses are ordered after 1312 * the reset. 1313 */ 1314 if (kvm_check_request(KVM_REQ_VCPU_RESET, vcpu)) 1315 kvm_reset_vcpu(vcpu); 1316 1317 if (ioctl == KVM_SET_ONE_REG) 1318 r = kvm_arm_set_reg(vcpu, ®); 1319 else 1320 r = kvm_arm_get_reg(vcpu, ®); 1321 break; 1322 } 1323 case KVM_GET_REG_LIST: { 1324 struct kvm_reg_list __user *user_list = argp; 1325 struct kvm_reg_list reg_list; 1326 unsigned n; 1327 1328 r = -ENOEXEC; 1329 if (unlikely(!kvm_vcpu_initialized(vcpu))) 1330 break; 1331 1332 r = -EPERM; 1333 if (!kvm_arm_vcpu_is_finalized(vcpu)) 1334 break; 1335 1336 r = -EFAULT; 1337 if (copy_from_user(®_list, user_list, sizeof(reg_list))) 1338 break; 1339 n = reg_list.n; 1340 reg_list.n = kvm_arm_num_regs(vcpu); 1341 if (copy_to_user(user_list, ®_list, sizeof(reg_list))) 1342 break; 1343 r = -E2BIG; 1344 if (n < reg_list.n) 1345 break; 1346 r = kvm_arm_copy_reg_indices(vcpu, user_list->reg); 1347 break; 1348 } 1349 case KVM_SET_DEVICE_ATTR: { 1350 r = -EFAULT; 1351 if (copy_from_user(&attr, argp, sizeof(attr))) 1352 break; 1353 r = kvm_arm_vcpu_set_attr(vcpu, &attr); 1354 break; 1355 } 1356 case KVM_GET_DEVICE_ATTR: { 1357 r = -EFAULT; 1358 if (copy_from_user(&attr, argp, sizeof(attr))) 1359 break; 1360 r = kvm_arm_vcpu_get_attr(vcpu, &attr); 1361 break; 1362 } 1363 case KVM_HAS_DEVICE_ATTR: { 1364 r = -EFAULT; 1365 if (copy_from_user(&attr, argp, sizeof(attr))) 1366 break; 1367 r = kvm_arm_vcpu_has_attr(vcpu, &attr); 1368 break; 1369 } 1370 case KVM_GET_VCPU_EVENTS: { 1371 struct kvm_vcpu_events events; 1372 1373 if (kvm_arm_vcpu_get_events(vcpu, &events)) 1374 return -EINVAL; 1375 1376 if (copy_to_user(argp, &events, sizeof(events))) 1377 return -EFAULT; 1378 1379 return 0; 1380 } 1381 case KVM_SET_VCPU_EVENTS: { 1382 struct kvm_vcpu_events events; 1383 1384 if (copy_from_user(&events, argp, sizeof(events))) 1385 return -EFAULT; 1386 1387 return kvm_arm_vcpu_set_events(vcpu, &events); 1388 } 1389 case KVM_ARM_VCPU_FINALIZE: { 1390 int what; 1391 1392 if (!kvm_vcpu_initialized(vcpu)) 1393 return -ENOEXEC; 1394 1395 if (get_user(what, (const int __user *)argp)) 1396 return -EFAULT; 1397 1398 return kvm_arm_vcpu_finalize(vcpu, what); 1399 } 1400 default: 1401 r = -EINVAL; 1402 } 1403 1404 return r; 1405 } 1406 1407 void kvm_arch_sync_dirty_log(struct kvm *kvm, struct kvm_memory_slot *memslot) 1408 { 1409 1410 } 1411 1412 void kvm_arch_flush_remote_tlbs_memslot(struct kvm *kvm, 1413 const struct kvm_memory_slot *memslot) 1414 { 1415 kvm_flush_remote_tlbs(kvm); 1416 } 1417 1418 static int kvm_vm_ioctl_set_device_addr(struct kvm *kvm, 1419 struct kvm_arm_device_addr *dev_addr) 1420 { 1421 switch (FIELD_GET(KVM_ARM_DEVICE_ID_MASK, dev_addr->id)) { 1422 case KVM_ARM_DEVICE_VGIC_V2: 1423 if (!vgic_present) 1424 return -ENXIO; 1425 return kvm_set_legacy_vgic_v2_addr(kvm, dev_addr); 1426 default: 1427 return -ENODEV; 1428 } 1429 } 1430 1431 long kvm_arch_vm_ioctl(struct file *filp, 1432 unsigned int ioctl, unsigned long arg) 1433 { 1434 struct kvm *kvm = filp->private_data; 1435 void __user *argp = (void __user *)arg; 1436 1437 switch (ioctl) { 1438 case KVM_CREATE_IRQCHIP: { 1439 int ret; 1440 if (!vgic_present) 1441 return -ENXIO; 1442 mutex_lock(&kvm->lock); 1443 ret = kvm_vgic_create(kvm, KVM_DEV_TYPE_ARM_VGIC_V2); 1444 mutex_unlock(&kvm->lock); 1445 return ret; 1446 } 1447 case KVM_ARM_SET_DEVICE_ADDR: { 1448 struct kvm_arm_device_addr dev_addr; 1449 1450 if (copy_from_user(&dev_addr, argp, sizeof(dev_addr))) 1451 return -EFAULT; 1452 return kvm_vm_ioctl_set_device_addr(kvm, &dev_addr); 1453 } 1454 case KVM_ARM_PREFERRED_TARGET: { 1455 struct kvm_vcpu_init init; 1456 1457 kvm_vcpu_preferred_target(&init); 1458 1459 if (copy_to_user(argp, &init, sizeof(init))) 1460 return -EFAULT; 1461 1462 return 0; 1463 } 1464 case KVM_ARM_MTE_COPY_TAGS: { 1465 struct kvm_arm_copy_mte_tags copy_tags; 1466 1467 if (copy_from_user(©_tags, argp, sizeof(copy_tags))) 1468 return -EFAULT; 1469 return kvm_vm_ioctl_mte_copy_tags(kvm, ©_tags); 1470 } 1471 default: 1472 return -EINVAL; 1473 } 1474 } 1475 1476 static unsigned long nvhe_percpu_size(void) 1477 { 1478 return (unsigned long)CHOOSE_NVHE_SYM(__per_cpu_end) - 1479 (unsigned long)CHOOSE_NVHE_SYM(__per_cpu_start); 1480 } 1481 1482 static unsigned long nvhe_percpu_order(void) 1483 { 1484 unsigned long size = nvhe_percpu_size(); 1485 1486 return size ? get_order(size) : 0; 1487 } 1488 1489 /* A lookup table holding the hypervisor VA for each vector slot */ 1490 static void *hyp_spectre_vector_selector[BP_HARDEN_EL2_SLOTS]; 1491 1492 static void kvm_init_vector_slot(void *base, enum arm64_hyp_spectre_vector slot) 1493 { 1494 hyp_spectre_vector_selector[slot] = __kvm_vector_slot2addr(base, slot); 1495 } 1496 1497 static int kvm_init_vector_slots(void) 1498 { 1499 int err; 1500 void *base; 1501 1502 base = kern_hyp_va(kvm_ksym_ref(__kvm_hyp_vector)); 1503 kvm_init_vector_slot(base, HYP_VECTOR_DIRECT); 1504 1505 base = kern_hyp_va(kvm_ksym_ref(__bp_harden_hyp_vecs)); 1506 kvm_init_vector_slot(base, HYP_VECTOR_SPECTRE_DIRECT); 1507 1508 if (kvm_system_needs_idmapped_vectors() && 1509 !is_protected_kvm_enabled()) { 1510 err = create_hyp_exec_mappings(__pa_symbol(__bp_harden_hyp_vecs), 1511 __BP_HARDEN_HYP_VECS_SZ, &base); 1512 if (err) 1513 return err; 1514 } 1515 1516 kvm_init_vector_slot(base, HYP_VECTOR_INDIRECT); 1517 kvm_init_vector_slot(base, HYP_VECTOR_SPECTRE_INDIRECT); 1518 return 0; 1519 } 1520 1521 static void cpu_prepare_hyp_mode(int cpu) 1522 { 1523 struct kvm_nvhe_init_params *params = per_cpu_ptr_nvhe_sym(kvm_init_params, cpu); 1524 unsigned long tcr; 1525 1526 /* 1527 * Calculate the raw per-cpu offset without a translation from the 1528 * kernel's mapping to the linear mapping, and store it in tpidr_el2 1529 * so that we can use adr_l to access per-cpu variables in EL2. 1530 * Also drop the KASAN tag which gets in the way... 1531 */ 1532 params->tpidr_el2 = (unsigned long)kasan_reset_tag(per_cpu_ptr_nvhe_sym(__per_cpu_start, cpu)) - 1533 (unsigned long)kvm_ksym_ref(CHOOSE_NVHE_SYM(__per_cpu_start)); 1534 1535 params->mair_el2 = read_sysreg(mair_el1); 1536 1537 /* 1538 * The ID map may be configured to use an extended virtual address 1539 * range. This is only the case if system RAM is out of range for the 1540 * currently configured page size and VA_BITS, in which case we will 1541 * also need the extended virtual range for the HYP ID map, or we won't 1542 * be able to enable the EL2 MMU. 1543 * 1544 * However, at EL2, there is only one TTBR register, and we can't switch 1545 * between translation tables *and* update TCR_EL2.T0SZ at the same 1546 * time. Bottom line: we need to use the extended range with *both* our 1547 * translation tables. 1548 * 1549 * So use the same T0SZ value we use for the ID map. 1550 */ 1551 tcr = (read_sysreg(tcr_el1) & TCR_EL2_MASK) | TCR_EL2_RES1; 1552 tcr &= ~TCR_T0SZ_MASK; 1553 tcr |= (idmap_t0sz & GENMASK(TCR_TxSZ_WIDTH - 1, 0)) << TCR_T0SZ_OFFSET; 1554 params->tcr_el2 = tcr; 1555 1556 params->pgd_pa = kvm_mmu_get_httbr(); 1557 if (is_protected_kvm_enabled()) 1558 params->hcr_el2 = HCR_HOST_NVHE_PROTECTED_FLAGS; 1559 else 1560 params->hcr_el2 = HCR_HOST_NVHE_FLAGS; 1561 params->vttbr = params->vtcr = 0; 1562 1563 /* 1564 * Flush the init params from the data cache because the struct will 1565 * be read while the MMU is off. 1566 */ 1567 kvm_flush_dcache_to_poc(params, sizeof(*params)); 1568 } 1569 1570 static void hyp_install_host_vector(void) 1571 { 1572 struct kvm_nvhe_init_params *params; 1573 struct arm_smccc_res res; 1574 1575 /* Switch from the HYP stub to our own HYP init vector */ 1576 __hyp_set_vectors(kvm_get_idmap_vector()); 1577 1578 /* 1579 * Call initialization code, and switch to the full blown HYP code. 1580 * If the cpucaps haven't been finalized yet, something has gone very 1581 * wrong, and hyp will crash and burn when it uses any 1582 * cpus_have_const_cap() wrapper. 1583 */ 1584 BUG_ON(!system_capabilities_finalized()); 1585 params = this_cpu_ptr_nvhe_sym(kvm_init_params); 1586 arm_smccc_1_1_hvc(KVM_HOST_SMCCC_FUNC(__kvm_hyp_init), virt_to_phys(params), &res); 1587 WARN_ON(res.a0 != SMCCC_RET_SUCCESS); 1588 } 1589 1590 static void cpu_init_hyp_mode(void) 1591 { 1592 hyp_install_host_vector(); 1593 1594 /* 1595 * Disabling SSBD on a non-VHE system requires us to enable SSBS 1596 * at EL2. 1597 */ 1598 if (this_cpu_has_cap(ARM64_SSBS) && 1599 arm64_get_spectre_v4_state() == SPECTRE_VULNERABLE) { 1600 kvm_call_hyp_nvhe(__kvm_enable_ssbs); 1601 } 1602 } 1603 1604 static void cpu_hyp_reset(void) 1605 { 1606 if (!is_kernel_in_hyp_mode()) 1607 __hyp_reset_vectors(); 1608 } 1609 1610 /* 1611 * EL2 vectors can be mapped and rerouted in a number of ways, 1612 * depending on the kernel configuration and CPU present: 1613 * 1614 * - If the CPU is affected by Spectre-v2, the hardening sequence is 1615 * placed in one of the vector slots, which is executed before jumping 1616 * to the real vectors. 1617 * 1618 * - If the CPU also has the ARM64_SPECTRE_V3A cap, the slot 1619 * containing the hardening sequence is mapped next to the idmap page, 1620 * and executed before jumping to the real vectors. 1621 * 1622 * - If the CPU only has the ARM64_SPECTRE_V3A cap, then an 1623 * empty slot is selected, mapped next to the idmap page, and 1624 * executed before jumping to the real vectors. 1625 * 1626 * Note that ARM64_SPECTRE_V3A is somewhat incompatible with 1627 * VHE, as we don't have hypervisor-specific mappings. If the system 1628 * is VHE and yet selects this capability, it will be ignored. 1629 */ 1630 static void cpu_set_hyp_vector(void) 1631 { 1632 struct bp_hardening_data *data = this_cpu_ptr(&bp_hardening_data); 1633 void *vector = hyp_spectre_vector_selector[data->slot]; 1634 1635 if (!is_protected_kvm_enabled()) 1636 *this_cpu_ptr_hyp_sym(kvm_hyp_vector) = (unsigned long)vector; 1637 else 1638 kvm_call_hyp_nvhe(__pkvm_cpu_set_vector, data->slot); 1639 } 1640 1641 static void cpu_hyp_init_context(void) 1642 { 1643 kvm_init_host_cpu_context(&this_cpu_ptr_hyp_sym(kvm_host_data)->host_ctxt); 1644 1645 if (!is_kernel_in_hyp_mode()) 1646 cpu_init_hyp_mode(); 1647 } 1648 1649 static void cpu_hyp_init_features(void) 1650 { 1651 cpu_set_hyp_vector(); 1652 kvm_arm_init_debug(); 1653 1654 if (is_kernel_in_hyp_mode()) 1655 kvm_timer_init_vhe(); 1656 1657 if (vgic_present) 1658 kvm_vgic_init_cpu_hardware(); 1659 } 1660 1661 static void cpu_hyp_reinit(void) 1662 { 1663 cpu_hyp_reset(); 1664 cpu_hyp_init_context(); 1665 cpu_hyp_init_features(); 1666 } 1667 1668 static void _kvm_arch_hardware_enable(void *discard) 1669 { 1670 if (!__this_cpu_read(kvm_arm_hardware_enabled)) { 1671 cpu_hyp_reinit(); 1672 __this_cpu_write(kvm_arm_hardware_enabled, 1); 1673 } 1674 } 1675 1676 int kvm_arch_hardware_enable(void) 1677 { 1678 _kvm_arch_hardware_enable(NULL); 1679 return 0; 1680 } 1681 1682 static void _kvm_arch_hardware_disable(void *discard) 1683 { 1684 if (__this_cpu_read(kvm_arm_hardware_enabled)) { 1685 cpu_hyp_reset(); 1686 __this_cpu_write(kvm_arm_hardware_enabled, 0); 1687 } 1688 } 1689 1690 void kvm_arch_hardware_disable(void) 1691 { 1692 if (!is_protected_kvm_enabled()) 1693 _kvm_arch_hardware_disable(NULL); 1694 } 1695 1696 #ifdef CONFIG_CPU_PM 1697 static int hyp_init_cpu_pm_notifier(struct notifier_block *self, 1698 unsigned long cmd, 1699 void *v) 1700 { 1701 /* 1702 * kvm_arm_hardware_enabled is left with its old value over 1703 * PM_ENTER->PM_EXIT. It is used to indicate PM_EXIT should 1704 * re-enable hyp. 1705 */ 1706 switch (cmd) { 1707 case CPU_PM_ENTER: 1708 if (__this_cpu_read(kvm_arm_hardware_enabled)) 1709 /* 1710 * don't update kvm_arm_hardware_enabled here 1711 * so that the hardware will be re-enabled 1712 * when we resume. See below. 1713 */ 1714 cpu_hyp_reset(); 1715 1716 return NOTIFY_OK; 1717 case CPU_PM_ENTER_FAILED: 1718 case CPU_PM_EXIT: 1719 if (__this_cpu_read(kvm_arm_hardware_enabled)) 1720 /* The hardware was enabled before suspend. */ 1721 cpu_hyp_reinit(); 1722 1723 return NOTIFY_OK; 1724 1725 default: 1726 return NOTIFY_DONE; 1727 } 1728 } 1729 1730 static struct notifier_block hyp_init_cpu_pm_nb = { 1731 .notifier_call = hyp_init_cpu_pm_notifier, 1732 }; 1733 1734 static void hyp_cpu_pm_init(void) 1735 { 1736 if (!is_protected_kvm_enabled()) 1737 cpu_pm_register_notifier(&hyp_init_cpu_pm_nb); 1738 } 1739 static void hyp_cpu_pm_exit(void) 1740 { 1741 if (!is_protected_kvm_enabled()) 1742 cpu_pm_unregister_notifier(&hyp_init_cpu_pm_nb); 1743 } 1744 #else 1745 static inline void hyp_cpu_pm_init(void) 1746 { 1747 } 1748 static inline void hyp_cpu_pm_exit(void) 1749 { 1750 } 1751 #endif 1752 1753 static void init_cpu_logical_map(void) 1754 { 1755 unsigned int cpu; 1756 1757 /* 1758 * Copy the MPIDR <-> logical CPU ID mapping to hyp. 1759 * Only copy the set of online CPUs whose features have been checked 1760 * against the finalized system capabilities. The hypervisor will not 1761 * allow any other CPUs from the `possible` set to boot. 1762 */ 1763 for_each_online_cpu(cpu) 1764 hyp_cpu_logical_map[cpu] = cpu_logical_map(cpu); 1765 } 1766 1767 #define init_psci_0_1_impl_state(config, what) \ 1768 config.psci_0_1_ ## what ## _implemented = psci_ops.what 1769 1770 static bool init_psci_relay(void) 1771 { 1772 /* 1773 * If PSCI has not been initialized, protected KVM cannot install 1774 * itself on newly booted CPUs. 1775 */ 1776 if (!psci_ops.get_version) { 1777 kvm_err("Cannot initialize protected mode without PSCI\n"); 1778 return false; 1779 } 1780 1781 kvm_host_psci_config.version = psci_ops.get_version(); 1782 1783 if (kvm_host_psci_config.version == PSCI_VERSION(0, 1)) { 1784 kvm_host_psci_config.function_ids_0_1 = get_psci_0_1_function_ids(); 1785 init_psci_0_1_impl_state(kvm_host_psci_config, cpu_suspend); 1786 init_psci_0_1_impl_state(kvm_host_psci_config, cpu_on); 1787 init_psci_0_1_impl_state(kvm_host_psci_config, cpu_off); 1788 init_psci_0_1_impl_state(kvm_host_psci_config, migrate); 1789 } 1790 return true; 1791 } 1792 1793 static int init_subsystems(void) 1794 { 1795 int err = 0; 1796 1797 /* 1798 * Enable hardware so that subsystem initialisation can access EL2. 1799 */ 1800 on_each_cpu(_kvm_arch_hardware_enable, NULL, 1); 1801 1802 /* 1803 * Register CPU lower-power notifier 1804 */ 1805 hyp_cpu_pm_init(); 1806 1807 /* 1808 * Init HYP view of VGIC 1809 */ 1810 err = kvm_vgic_hyp_init(); 1811 switch (err) { 1812 case 0: 1813 vgic_present = true; 1814 break; 1815 case -ENODEV: 1816 case -ENXIO: 1817 vgic_present = false; 1818 err = 0; 1819 break; 1820 default: 1821 goto out; 1822 } 1823 1824 /* 1825 * Init HYP architected timer support 1826 */ 1827 err = kvm_timer_hyp_init(vgic_present); 1828 if (err) 1829 goto out; 1830 1831 kvm_register_perf_callbacks(NULL); 1832 1833 out: 1834 if (err || !is_protected_kvm_enabled()) 1835 on_each_cpu(_kvm_arch_hardware_disable, NULL, 1); 1836 1837 return err; 1838 } 1839 1840 static void teardown_hyp_mode(void) 1841 { 1842 int cpu; 1843 1844 free_hyp_pgds(); 1845 for_each_possible_cpu(cpu) { 1846 free_page(per_cpu(kvm_arm_hyp_stack_page, cpu)); 1847 free_pages(kvm_arm_hyp_percpu_base[cpu], nvhe_percpu_order()); 1848 } 1849 } 1850 1851 static int do_pkvm_init(u32 hyp_va_bits) 1852 { 1853 void *per_cpu_base = kvm_ksym_ref(kvm_arm_hyp_percpu_base); 1854 int ret; 1855 1856 preempt_disable(); 1857 cpu_hyp_init_context(); 1858 ret = kvm_call_hyp_nvhe(__pkvm_init, hyp_mem_base, hyp_mem_size, 1859 num_possible_cpus(), kern_hyp_va(per_cpu_base), 1860 hyp_va_bits); 1861 cpu_hyp_init_features(); 1862 1863 /* 1864 * The stub hypercalls are now disabled, so set our local flag to 1865 * prevent a later re-init attempt in kvm_arch_hardware_enable(). 1866 */ 1867 __this_cpu_write(kvm_arm_hardware_enabled, 1); 1868 preempt_enable(); 1869 1870 return ret; 1871 } 1872 1873 static int kvm_hyp_init_protection(u32 hyp_va_bits) 1874 { 1875 void *addr = phys_to_virt(hyp_mem_base); 1876 int ret; 1877 1878 kvm_nvhe_sym(id_aa64pfr0_el1_sys_val) = read_sanitised_ftr_reg(SYS_ID_AA64PFR0_EL1); 1879 kvm_nvhe_sym(id_aa64pfr1_el1_sys_val) = read_sanitised_ftr_reg(SYS_ID_AA64PFR1_EL1); 1880 kvm_nvhe_sym(id_aa64isar0_el1_sys_val) = read_sanitised_ftr_reg(SYS_ID_AA64ISAR0_EL1); 1881 kvm_nvhe_sym(id_aa64isar1_el1_sys_val) = read_sanitised_ftr_reg(SYS_ID_AA64ISAR1_EL1); 1882 kvm_nvhe_sym(id_aa64isar2_el1_sys_val) = read_sanitised_ftr_reg(SYS_ID_AA64ISAR2_EL1); 1883 kvm_nvhe_sym(id_aa64mmfr0_el1_sys_val) = read_sanitised_ftr_reg(SYS_ID_AA64MMFR0_EL1); 1884 kvm_nvhe_sym(id_aa64mmfr1_el1_sys_val) = read_sanitised_ftr_reg(SYS_ID_AA64MMFR1_EL1); 1885 kvm_nvhe_sym(id_aa64mmfr2_el1_sys_val) = read_sanitised_ftr_reg(SYS_ID_AA64MMFR2_EL1); 1886 1887 ret = create_hyp_mappings(addr, addr + hyp_mem_size, PAGE_HYP); 1888 if (ret) 1889 return ret; 1890 1891 ret = do_pkvm_init(hyp_va_bits); 1892 if (ret) 1893 return ret; 1894 1895 free_hyp_pgds(); 1896 1897 return 0; 1898 } 1899 1900 /** 1901 * Inits Hyp-mode on all online CPUs 1902 */ 1903 static int init_hyp_mode(void) 1904 { 1905 u32 hyp_va_bits; 1906 int cpu; 1907 int err = -ENOMEM; 1908 1909 /* 1910 * The protected Hyp-mode cannot be initialized if the memory pool 1911 * allocation has failed. 1912 */ 1913 if (is_protected_kvm_enabled() && !hyp_mem_base) 1914 goto out_err; 1915 1916 /* 1917 * Allocate Hyp PGD and setup Hyp identity mapping 1918 */ 1919 err = kvm_mmu_init(&hyp_va_bits); 1920 if (err) 1921 goto out_err; 1922 1923 /* 1924 * Allocate stack pages for Hypervisor-mode 1925 */ 1926 for_each_possible_cpu(cpu) { 1927 unsigned long stack_page; 1928 1929 stack_page = __get_free_page(GFP_KERNEL); 1930 if (!stack_page) { 1931 err = -ENOMEM; 1932 goto out_err; 1933 } 1934 1935 per_cpu(kvm_arm_hyp_stack_page, cpu) = stack_page; 1936 } 1937 1938 /* 1939 * Allocate and initialize pages for Hypervisor-mode percpu regions. 1940 */ 1941 for_each_possible_cpu(cpu) { 1942 struct page *page; 1943 void *page_addr; 1944 1945 page = alloc_pages(GFP_KERNEL, nvhe_percpu_order()); 1946 if (!page) { 1947 err = -ENOMEM; 1948 goto out_err; 1949 } 1950 1951 page_addr = page_address(page); 1952 memcpy(page_addr, CHOOSE_NVHE_SYM(__per_cpu_start), nvhe_percpu_size()); 1953 kvm_arm_hyp_percpu_base[cpu] = (unsigned long)page_addr; 1954 } 1955 1956 /* 1957 * Map the Hyp-code called directly from the host 1958 */ 1959 err = create_hyp_mappings(kvm_ksym_ref(__hyp_text_start), 1960 kvm_ksym_ref(__hyp_text_end), PAGE_HYP_EXEC); 1961 if (err) { 1962 kvm_err("Cannot map world-switch code\n"); 1963 goto out_err; 1964 } 1965 1966 err = create_hyp_mappings(kvm_ksym_ref(__hyp_rodata_start), 1967 kvm_ksym_ref(__hyp_rodata_end), PAGE_HYP_RO); 1968 if (err) { 1969 kvm_err("Cannot map .hyp.rodata section\n"); 1970 goto out_err; 1971 } 1972 1973 err = create_hyp_mappings(kvm_ksym_ref(__start_rodata), 1974 kvm_ksym_ref(__end_rodata), PAGE_HYP_RO); 1975 if (err) { 1976 kvm_err("Cannot map rodata section\n"); 1977 goto out_err; 1978 } 1979 1980 /* 1981 * .hyp.bss is guaranteed to be placed at the beginning of the .bss 1982 * section thanks to an assertion in the linker script. Map it RW and 1983 * the rest of .bss RO. 1984 */ 1985 err = create_hyp_mappings(kvm_ksym_ref(__hyp_bss_start), 1986 kvm_ksym_ref(__hyp_bss_end), PAGE_HYP); 1987 if (err) { 1988 kvm_err("Cannot map hyp bss section: %d\n", err); 1989 goto out_err; 1990 } 1991 1992 err = create_hyp_mappings(kvm_ksym_ref(__hyp_bss_end), 1993 kvm_ksym_ref(__bss_stop), PAGE_HYP_RO); 1994 if (err) { 1995 kvm_err("Cannot map bss section\n"); 1996 goto out_err; 1997 } 1998 1999 /* 2000 * Map the Hyp stack pages 2001 */ 2002 for_each_possible_cpu(cpu) { 2003 struct kvm_nvhe_init_params *params = per_cpu_ptr_nvhe_sym(kvm_init_params, cpu); 2004 char *stack_page = (char *)per_cpu(kvm_arm_hyp_stack_page, cpu); 2005 unsigned long hyp_addr; 2006 2007 /* 2008 * Allocate a contiguous HYP private VA range for the stack 2009 * and guard page. The allocation is also aligned based on 2010 * the order of its size. 2011 */ 2012 err = hyp_alloc_private_va_range(PAGE_SIZE * 2, &hyp_addr); 2013 if (err) { 2014 kvm_err("Cannot allocate hyp stack guard page\n"); 2015 goto out_err; 2016 } 2017 2018 /* 2019 * Since the stack grows downwards, map the stack to the page 2020 * at the higher address and leave the lower guard page 2021 * unbacked. 2022 * 2023 * Any valid stack address now has the PAGE_SHIFT bit as 1 2024 * and addresses corresponding to the guard page have the 2025 * PAGE_SHIFT bit as 0 - this is used for overflow detection. 2026 */ 2027 err = __create_hyp_mappings(hyp_addr + PAGE_SIZE, PAGE_SIZE, 2028 __pa(stack_page), PAGE_HYP); 2029 if (err) { 2030 kvm_err("Cannot map hyp stack\n"); 2031 goto out_err; 2032 } 2033 2034 /* 2035 * Save the stack PA in nvhe_init_params. This will be needed 2036 * to recreate the stack mapping in protected nVHE mode. 2037 * __hyp_pa() won't do the right thing there, since the stack 2038 * has been mapped in the flexible private VA space. 2039 */ 2040 params->stack_pa = __pa(stack_page); 2041 2042 params->stack_hyp_va = hyp_addr + (2 * PAGE_SIZE); 2043 } 2044 2045 for_each_possible_cpu(cpu) { 2046 char *percpu_begin = (char *)kvm_arm_hyp_percpu_base[cpu]; 2047 char *percpu_end = percpu_begin + nvhe_percpu_size(); 2048 2049 /* Map Hyp percpu pages */ 2050 err = create_hyp_mappings(percpu_begin, percpu_end, PAGE_HYP); 2051 if (err) { 2052 kvm_err("Cannot map hyp percpu region\n"); 2053 goto out_err; 2054 } 2055 2056 /* Prepare the CPU initialization parameters */ 2057 cpu_prepare_hyp_mode(cpu); 2058 } 2059 2060 if (is_protected_kvm_enabled()) { 2061 init_cpu_logical_map(); 2062 2063 if (!init_psci_relay()) { 2064 err = -ENODEV; 2065 goto out_err; 2066 } 2067 } 2068 2069 if (is_protected_kvm_enabled()) { 2070 err = kvm_hyp_init_protection(hyp_va_bits); 2071 if (err) { 2072 kvm_err("Failed to init hyp memory protection\n"); 2073 goto out_err; 2074 } 2075 } 2076 2077 return 0; 2078 2079 out_err: 2080 teardown_hyp_mode(); 2081 kvm_err("error initializing Hyp mode: %d\n", err); 2082 return err; 2083 } 2084 2085 static void _kvm_host_prot_finalize(void *arg) 2086 { 2087 int *err = arg; 2088 2089 if (WARN_ON(kvm_call_hyp_nvhe(__pkvm_prot_finalize))) 2090 WRITE_ONCE(*err, -EINVAL); 2091 } 2092 2093 static int pkvm_drop_host_privileges(void) 2094 { 2095 int ret = 0; 2096 2097 /* 2098 * Flip the static key upfront as that may no longer be possible 2099 * once the host stage 2 is installed. 2100 */ 2101 static_branch_enable(&kvm_protected_mode_initialized); 2102 on_each_cpu(_kvm_host_prot_finalize, &ret, 1); 2103 return ret; 2104 } 2105 2106 static int finalize_hyp_mode(void) 2107 { 2108 if (!is_protected_kvm_enabled()) 2109 return 0; 2110 2111 /* 2112 * Exclude HYP sections from kmemleak so that they don't get peeked 2113 * at, which would end badly once inaccessible. 2114 */ 2115 kmemleak_free_part(__hyp_bss_start, __hyp_bss_end - __hyp_bss_start); 2116 kmemleak_free_part_phys(hyp_mem_base, hyp_mem_size); 2117 return pkvm_drop_host_privileges(); 2118 } 2119 2120 struct kvm_vcpu *kvm_mpidr_to_vcpu(struct kvm *kvm, unsigned long mpidr) 2121 { 2122 struct kvm_vcpu *vcpu; 2123 unsigned long i; 2124 2125 mpidr &= MPIDR_HWID_BITMASK; 2126 kvm_for_each_vcpu(i, vcpu, kvm) { 2127 if (mpidr == kvm_vcpu_get_mpidr_aff(vcpu)) 2128 return vcpu; 2129 } 2130 return NULL; 2131 } 2132 2133 bool kvm_arch_has_irq_bypass(void) 2134 { 2135 return true; 2136 } 2137 2138 int kvm_arch_irq_bypass_add_producer(struct irq_bypass_consumer *cons, 2139 struct irq_bypass_producer *prod) 2140 { 2141 struct kvm_kernel_irqfd *irqfd = 2142 container_of(cons, struct kvm_kernel_irqfd, consumer); 2143 2144 return kvm_vgic_v4_set_forwarding(irqfd->kvm, prod->irq, 2145 &irqfd->irq_entry); 2146 } 2147 void kvm_arch_irq_bypass_del_producer(struct irq_bypass_consumer *cons, 2148 struct irq_bypass_producer *prod) 2149 { 2150 struct kvm_kernel_irqfd *irqfd = 2151 container_of(cons, struct kvm_kernel_irqfd, consumer); 2152 2153 kvm_vgic_v4_unset_forwarding(irqfd->kvm, prod->irq, 2154 &irqfd->irq_entry); 2155 } 2156 2157 void kvm_arch_irq_bypass_stop(struct irq_bypass_consumer *cons) 2158 { 2159 struct kvm_kernel_irqfd *irqfd = 2160 container_of(cons, struct kvm_kernel_irqfd, consumer); 2161 2162 kvm_arm_halt_guest(irqfd->kvm); 2163 } 2164 2165 void kvm_arch_irq_bypass_start(struct irq_bypass_consumer *cons) 2166 { 2167 struct kvm_kernel_irqfd *irqfd = 2168 container_of(cons, struct kvm_kernel_irqfd, consumer); 2169 2170 kvm_arm_resume_guest(irqfd->kvm); 2171 } 2172 2173 /** 2174 * Initialize Hyp-mode and memory mappings on all CPUs. 2175 */ 2176 int kvm_arch_init(void *opaque) 2177 { 2178 int err; 2179 bool in_hyp_mode; 2180 2181 if (!is_hyp_mode_available()) { 2182 kvm_info("HYP mode not available\n"); 2183 return -ENODEV; 2184 } 2185 2186 if (kvm_get_mode() == KVM_MODE_NONE) { 2187 kvm_info("KVM disabled from command line\n"); 2188 return -ENODEV; 2189 } 2190 2191 err = kvm_sys_reg_table_init(); 2192 if (err) { 2193 kvm_info("Error initializing system register tables"); 2194 return err; 2195 } 2196 2197 in_hyp_mode = is_kernel_in_hyp_mode(); 2198 2199 if (cpus_have_final_cap(ARM64_WORKAROUND_DEVICE_LOAD_ACQUIRE) || 2200 cpus_have_final_cap(ARM64_WORKAROUND_1508412)) 2201 kvm_info("Guests without required CPU erratum workarounds can deadlock system!\n" \ 2202 "Only trusted guests should be used on this system.\n"); 2203 2204 err = kvm_set_ipa_limit(); 2205 if (err) 2206 return err; 2207 2208 err = kvm_arm_init_sve(); 2209 if (err) 2210 return err; 2211 2212 err = kvm_arm_vmid_alloc_init(); 2213 if (err) { 2214 kvm_err("Failed to initialize VMID allocator.\n"); 2215 return err; 2216 } 2217 2218 if (!in_hyp_mode) { 2219 err = init_hyp_mode(); 2220 if (err) 2221 goto out_err; 2222 } 2223 2224 err = kvm_init_vector_slots(); 2225 if (err) { 2226 kvm_err("Cannot initialise vector slots\n"); 2227 goto out_err; 2228 } 2229 2230 err = init_subsystems(); 2231 if (err) 2232 goto out_hyp; 2233 2234 if (!in_hyp_mode) { 2235 err = finalize_hyp_mode(); 2236 if (err) { 2237 kvm_err("Failed to finalize Hyp protection\n"); 2238 goto out_hyp; 2239 } 2240 } 2241 2242 if (is_protected_kvm_enabled()) { 2243 kvm_info("Protected nVHE mode initialized successfully\n"); 2244 } else if (in_hyp_mode) { 2245 kvm_info("VHE mode initialized successfully\n"); 2246 } else { 2247 kvm_info("Hyp mode initialized successfully\n"); 2248 } 2249 2250 return 0; 2251 2252 out_hyp: 2253 hyp_cpu_pm_exit(); 2254 if (!in_hyp_mode) 2255 teardown_hyp_mode(); 2256 out_err: 2257 kvm_arm_vmid_alloc_free(); 2258 return err; 2259 } 2260 2261 /* NOP: Compiling as a module not supported */ 2262 void kvm_arch_exit(void) 2263 { 2264 kvm_unregister_perf_callbacks(); 2265 } 2266 2267 static int __init early_kvm_mode_cfg(char *arg) 2268 { 2269 if (!arg) 2270 return -EINVAL; 2271 2272 if (strcmp(arg, "none") == 0) { 2273 kvm_mode = KVM_MODE_NONE; 2274 return 0; 2275 } 2276 2277 if (!is_hyp_mode_available()) { 2278 pr_warn_once("KVM is not available. Ignoring kvm-arm.mode\n"); 2279 return 0; 2280 } 2281 2282 if (strcmp(arg, "protected") == 0) { 2283 if (!is_kernel_in_hyp_mode()) 2284 kvm_mode = KVM_MODE_PROTECTED; 2285 else 2286 pr_warn_once("Protected KVM not available with VHE\n"); 2287 2288 return 0; 2289 } 2290 2291 if (strcmp(arg, "nvhe") == 0 && !WARN_ON(is_kernel_in_hyp_mode())) { 2292 kvm_mode = KVM_MODE_DEFAULT; 2293 return 0; 2294 } 2295 2296 return -EINVAL; 2297 } 2298 early_param("kvm-arm.mode", early_kvm_mode_cfg); 2299 2300 enum kvm_mode kvm_get_mode(void) 2301 { 2302 return kvm_mode; 2303 } 2304 2305 static int arm_init(void) 2306 { 2307 int rc = kvm_init(NULL, sizeof(struct kvm_vcpu), 0, THIS_MODULE); 2308 return rc; 2309 } 2310 2311 module_init(arm_init); 2312