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 default: 101 r = -EINVAL; 102 break; 103 } 104 105 return r; 106 } 107 108 static int kvm_arm_default_max_vcpus(void) 109 { 110 return vgic_present ? kvm_vgic_get_max_vcpus() : KVM_MAX_VCPUS; 111 } 112 113 static void set_default_spectre(struct kvm *kvm) 114 { 115 /* 116 * The default is to expose CSV2 == 1 if the HW isn't affected. 117 * Although this is a per-CPU feature, we make it global because 118 * asymmetric systems are just a nuisance. 119 * 120 * Userspace can override this as long as it doesn't promise 121 * the impossible. 122 */ 123 if (arm64_get_spectre_v2_state() == SPECTRE_UNAFFECTED) 124 kvm->arch.pfr0_csv2 = 1; 125 if (arm64_get_meltdown_state() == SPECTRE_UNAFFECTED) 126 kvm->arch.pfr0_csv3 = 1; 127 } 128 129 /** 130 * kvm_arch_init_vm - initializes a VM data structure 131 * @kvm: pointer to the KVM struct 132 */ 133 int kvm_arch_init_vm(struct kvm *kvm, unsigned long type) 134 { 135 int ret; 136 137 ret = kvm_arm_setup_stage2(kvm, type); 138 if (ret) 139 return ret; 140 141 ret = kvm_init_stage2_mmu(kvm, &kvm->arch.mmu); 142 if (ret) 143 return ret; 144 145 ret = kvm_share_hyp(kvm, kvm + 1); 146 if (ret) 147 goto out_free_stage2_pgd; 148 149 if (!zalloc_cpumask_var(&kvm->arch.supported_cpus, GFP_KERNEL)) 150 goto out_free_stage2_pgd; 151 cpumask_copy(kvm->arch.supported_cpus, cpu_possible_mask); 152 153 kvm_vgic_early_init(kvm); 154 155 /* The maximum number of VCPUs is limited by the host's GIC model */ 156 kvm->arch.max_vcpus = kvm_arm_default_max_vcpus(); 157 158 set_default_spectre(kvm); 159 160 return ret; 161 out_free_stage2_pgd: 162 kvm_free_stage2_pgd(&kvm->arch.mmu); 163 return ret; 164 } 165 166 vm_fault_t kvm_arch_vcpu_fault(struct kvm_vcpu *vcpu, struct vm_fault *vmf) 167 { 168 return VM_FAULT_SIGBUS; 169 } 170 171 172 /** 173 * kvm_arch_destroy_vm - destroy the VM data structure 174 * @kvm: pointer to the KVM struct 175 */ 176 void kvm_arch_destroy_vm(struct kvm *kvm) 177 { 178 bitmap_free(kvm->arch.pmu_filter); 179 free_cpumask_var(kvm->arch.supported_cpus); 180 181 kvm_vgic_destroy(kvm); 182 183 kvm_destroy_vcpus(kvm); 184 185 kvm_unshare_hyp(kvm, kvm + 1); 186 } 187 188 int kvm_vm_ioctl_check_extension(struct kvm *kvm, long ext) 189 { 190 int r; 191 switch (ext) { 192 case KVM_CAP_IRQCHIP: 193 r = vgic_present; 194 break; 195 case KVM_CAP_IOEVENTFD: 196 case KVM_CAP_DEVICE_CTRL: 197 case KVM_CAP_USER_MEMORY: 198 case KVM_CAP_SYNC_MMU: 199 case KVM_CAP_DESTROY_MEMORY_REGION_WORKS: 200 case KVM_CAP_ONE_REG: 201 case KVM_CAP_ARM_PSCI: 202 case KVM_CAP_ARM_PSCI_0_2: 203 case KVM_CAP_READONLY_MEM: 204 case KVM_CAP_MP_STATE: 205 case KVM_CAP_IMMEDIATE_EXIT: 206 case KVM_CAP_VCPU_EVENTS: 207 case KVM_CAP_ARM_IRQ_LINE_LAYOUT_2: 208 case KVM_CAP_ARM_NISV_TO_USER: 209 case KVM_CAP_ARM_INJECT_EXT_DABT: 210 case KVM_CAP_SET_GUEST_DEBUG: 211 case KVM_CAP_VCPU_ATTRIBUTES: 212 case KVM_CAP_PTP_KVM: 213 r = 1; 214 break; 215 case KVM_CAP_SET_GUEST_DEBUG2: 216 return KVM_GUESTDBG_VALID_MASK; 217 case KVM_CAP_ARM_SET_DEVICE_ADDR: 218 r = 1; 219 break; 220 case KVM_CAP_NR_VCPUS: 221 /* 222 * ARM64 treats KVM_CAP_NR_CPUS differently from all other 223 * architectures, as it does not always bound it to 224 * KVM_CAP_MAX_VCPUS. It should not matter much because 225 * this is just an advisory value. 226 */ 227 r = min_t(unsigned int, num_online_cpus(), 228 kvm_arm_default_max_vcpus()); 229 break; 230 case KVM_CAP_MAX_VCPUS: 231 case KVM_CAP_MAX_VCPU_ID: 232 if (kvm) 233 r = kvm->arch.max_vcpus; 234 else 235 r = kvm_arm_default_max_vcpus(); 236 break; 237 case KVM_CAP_MSI_DEVID: 238 if (!kvm) 239 r = -EINVAL; 240 else 241 r = kvm->arch.vgic.msis_require_devid; 242 break; 243 case KVM_CAP_ARM_USER_IRQ: 244 /* 245 * 1: EL1_VTIMER, EL1_PTIMER, and PMU. 246 * (bump this number if adding more devices) 247 */ 248 r = 1; 249 break; 250 case KVM_CAP_ARM_MTE: 251 r = system_supports_mte(); 252 break; 253 case KVM_CAP_STEAL_TIME: 254 r = kvm_arm_pvtime_supported(); 255 break; 256 case KVM_CAP_ARM_EL1_32BIT: 257 r = cpus_have_const_cap(ARM64_HAS_32BIT_EL1); 258 break; 259 case KVM_CAP_GUEST_DEBUG_HW_BPS: 260 r = get_num_brps(); 261 break; 262 case KVM_CAP_GUEST_DEBUG_HW_WPS: 263 r = get_num_wrps(); 264 break; 265 case KVM_CAP_ARM_PMU_V3: 266 r = kvm_arm_support_pmu_v3(); 267 break; 268 case KVM_CAP_ARM_INJECT_SERROR_ESR: 269 r = cpus_have_const_cap(ARM64_HAS_RAS_EXTN); 270 break; 271 case KVM_CAP_ARM_VM_IPA_SIZE: 272 r = get_kvm_ipa_limit(); 273 break; 274 case KVM_CAP_ARM_SVE: 275 r = system_supports_sve(); 276 break; 277 case KVM_CAP_ARM_PTRAUTH_ADDRESS: 278 case KVM_CAP_ARM_PTRAUTH_GENERIC: 279 r = system_has_full_ptr_auth(); 280 break; 281 default: 282 r = 0; 283 } 284 285 return r; 286 } 287 288 long kvm_arch_dev_ioctl(struct file *filp, 289 unsigned int ioctl, unsigned long arg) 290 { 291 return -EINVAL; 292 } 293 294 struct kvm *kvm_arch_alloc_vm(void) 295 { 296 size_t sz = sizeof(struct kvm); 297 298 if (!has_vhe()) 299 return kzalloc(sz, GFP_KERNEL_ACCOUNT); 300 301 return __vmalloc(sz, GFP_KERNEL_ACCOUNT | __GFP_HIGHMEM | __GFP_ZERO); 302 } 303 304 int kvm_arch_vcpu_precreate(struct kvm *kvm, unsigned int id) 305 { 306 if (irqchip_in_kernel(kvm) && vgic_initialized(kvm)) 307 return -EBUSY; 308 309 if (id >= kvm->arch.max_vcpus) 310 return -EINVAL; 311 312 return 0; 313 } 314 315 int kvm_arch_vcpu_create(struct kvm_vcpu *vcpu) 316 { 317 int err; 318 319 /* Force users to call KVM_ARM_VCPU_INIT */ 320 vcpu->arch.target = -1; 321 bitmap_zero(vcpu->arch.features, KVM_VCPU_MAX_FEATURES); 322 323 vcpu->arch.mmu_page_cache.gfp_zero = __GFP_ZERO; 324 325 /* Set up the timer */ 326 kvm_timer_vcpu_init(vcpu); 327 328 kvm_pmu_vcpu_init(vcpu); 329 330 kvm_arm_reset_debug_ptr(vcpu); 331 332 kvm_arm_pvtime_vcpu_init(&vcpu->arch); 333 334 vcpu->arch.hw_mmu = &vcpu->kvm->arch.mmu; 335 336 err = kvm_vgic_vcpu_init(vcpu); 337 if (err) 338 return err; 339 340 return kvm_share_hyp(vcpu, vcpu + 1); 341 } 342 343 void kvm_arch_vcpu_postcreate(struct kvm_vcpu *vcpu) 344 { 345 } 346 347 void kvm_arch_vcpu_destroy(struct kvm_vcpu *vcpu) 348 { 349 if (vcpu_has_run_once(vcpu) && unlikely(!irqchip_in_kernel(vcpu->kvm))) 350 static_branch_dec(&userspace_irqchip_in_use); 351 352 kvm_mmu_free_memory_cache(&vcpu->arch.mmu_page_cache); 353 kvm_timer_vcpu_terminate(vcpu); 354 kvm_pmu_vcpu_destroy(vcpu); 355 356 kvm_arm_vcpu_destroy(vcpu); 357 } 358 359 int kvm_cpu_has_pending_timer(struct kvm_vcpu *vcpu) 360 { 361 return kvm_timer_is_pending(vcpu); 362 } 363 364 void kvm_arch_vcpu_blocking(struct kvm_vcpu *vcpu) 365 { 366 367 } 368 369 void kvm_arch_vcpu_unblocking(struct kvm_vcpu *vcpu) 370 { 371 372 } 373 374 void kvm_arch_vcpu_load(struct kvm_vcpu *vcpu, int cpu) 375 { 376 struct kvm_s2_mmu *mmu; 377 int *last_ran; 378 379 mmu = vcpu->arch.hw_mmu; 380 last_ran = this_cpu_ptr(mmu->last_vcpu_ran); 381 382 /* 383 * We guarantee that both TLBs and I-cache are private to each 384 * vcpu. If detecting that a vcpu from the same VM has 385 * previously run on the same physical CPU, call into the 386 * hypervisor code to nuke the relevant contexts. 387 * 388 * We might get preempted before the vCPU actually runs, but 389 * over-invalidation doesn't affect correctness. 390 */ 391 if (*last_ran != vcpu->vcpu_id) { 392 kvm_call_hyp(__kvm_flush_cpu_context, mmu); 393 *last_ran = vcpu->vcpu_id; 394 } 395 396 vcpu->cpu = cpu; 397 398 kvm_vgic_load(vcpu); 399 kvm_timer_vcpu_load(vcpu); 400 if (has_vhe()) 401 kvm_vcpu_load_sysregs_vhe(vcpu); 402 kvm_arch_vcpu_load_fp(vcpu); 403 kvm_vcpu_pmu_restore_guest(vcpu); 404 if (kvm_arm_is_pvtime_enabled(&vcpu->arch)) 405 kvm_make_request(KVM_REQ_RECORD_STEAL, vcpu); 406 407 if (single_task_running()) 408 vcpu_clear_wfx_traps(vcpu); 409 else 410 vcpu_set_wfx_traps(vcpu); 411 412 if (vcpu_has_ptrauth(vcpu)) 413 vcpu_ptrauth_disable(vcpu); 414 kvm_arch_vcpu_load_debug_state_flags(vcpu); 415 416 if (!cpumask_test_cpu(smp_processor_id(), vcpu->kvm->arch.supported_cpus)) 417 vcpu_set_on_unsupported_cpu(vcpu); 418 } 419 420 void kvm_arch_vcpu_put(struct kvm_vcpu *vcpu) 421 { 422 kvm_arch_vcpu_put_debug_state_flags(vcpu); 423 kvm_arch_vcpu_put_fp(vcpu); 424 if (has_vhe()) 425 kvm_vcpu_put_sysregs_vhe(vcpu); 426 kvm_timer_vcpu_put(vcpu); 427 kvm_vgic_put(vcpu); 428 kvm_vcpu_pmu_restore_host(vcpu); 429 kvm_arm_vmid_clear_active(); 430 431 vcpu_clear_on_unsupported_cpu(vcpu); 432 vcpu->cpu = -1; 433 } 434 435 static void vcpu_power_off(struct kvm_vcpu *vcpu) 436 { 437 vcpu->arch.power_off = true; 438 kvm_make_request(KVM_REQ_SLEEP, vcpu); 439 kvm_vcpu_kick(vcpu); 440 } 441 442 int kvm_arch_vcpu_ioctl_get_mpstate(struct kvm_vcpu *vcpu, 443 struct kvm_mp_state *mp_state) 444 { 445 if (vcpu->arch.power_off) 446 mp_state->mp_state = KVM_MP_STATE_STOPPED; 447 else 448 mp_state->mp_state = KVM_MP_STATE_RUNNABLE; 449 450 return 0; 451 } 452 453 int kvm_arch_vcpu_ioctl_set_mpstate(struct kvm_vcpu *vcpu, 454 struct kvm_mp_state *mp_state) 455 { 456 int ret = 0; 457 458 switch (mp_state->mp_state) { 459 case KVM_MP_STATE_RUNNABLE: 460 vcpu->arch.power_off = false; 461 break; 462 case KVM_MP_STATE_STOPPED: 463 vcpu_power_off(vcpu); 464 break; 465 default: 466 ret = -EINVAL; 467 } 468 469 return ret; 470 } 471 472 /** 473 * kvm_arch_vcpu_runnable - determine if the vcpu can be scheduled 474 * @v: The VCPU pointer 475 * 476 * If the guest CPU is not waiting for interrupts or an interrupt line is 477 * asserted, the CPU is by definition runnable. 478 */ 479 int kvm_arch_vcpu_runnable(struct kvm_vcpu *v) 480 { 481 bool irq_lines = *vcpu_hcr(v) & (HCR_VI | HCR_VF); 482 return ((irq_lines || kvm_vgic_vcpu_pending_irq(v)) 483 && !v->arch.power_off && !v->arch.pause); 484 } 485 486 bool kvm_arch_vcpu_in_kernel(struct kvm_vcpu *vcpu) 487 { 488 return vcpu_mode_priv(vcpu); 489 } 490 491 #ifdef CONFIG_GUEST_PERF_EVENTS 492 unsigned long kvm_arch_vcpu_get_ip(struct kvm_vcpu *vcpu) 493 { 494 return *vcpu_pc(vcpu); 495 } 496 #endif 497 498 static int kvm_vcpu_initialized(struct kvm_vcpu *vcpu) 499 { 500 return vcpu->arch.target >= 0; 501 } 502 503 /* 504 * Handle both the initialisation that is being done when the vcpu is 505 * run for the first time, as well as the updates that must be 506 * performed each time we get a new thread dealing with this vcpu. 507 */ 508 int kvm_arch_vcpu_run_pid_change(struct kvm_vcpu *vcpu) 509 { 510 struct kvm *kvm = vcpu->kvm; 511 int ret; 512 513 if (!kvm_vcpu_initialized(vcpu)) 514 return -ENOEXEC; 515 516 if (!kvm_arm_vcpu_is_finalized(vcpu)) 517 return -EPERM; 518 519 ret = kvm_arch_vcpu_run_map_fp(vcpu); 520 if (ret) 521 return ret; 522 523 if (likely(vcpu_has_run_once(vcpu))) 524 return 0; 525 526 kvm_arm_vcpu_init_debug(vcpu); 527 528 if (likely(irqchip_in_kernel(kvm))) { 529 /* 530 * Map the VGIC hardware resources before running a vcpu the 531 * first time on this VM. 532 */ 533 ret = kvm_vgic_map_resources(kvm); 534 if (ret) 535 return ret; 536 } 537 538 ret = kvm_timer_enable(vcpu); 539 if (ret) 540 return ret; 541 542 ret = kvm_arm_pmu_v3_enable(vcpu); 543 if (ret) 544 return ret; 545 546 if (!irqchip_in_kernel(kvm)) { 547 /* 548 * Tell the rest of the code that there are userspace irqchip 549 * VMs in the wild. 550 */ 551 static_branch_inc(&userspace_irqchip_in_use); 552 } 553 554 /* 555 * Initialize traps for protected VMs. 556 * NOTE: Move to run in EL2 directly, rather than via a hypercall, once 557 * the code is in place for first run initialization at EL2. 558 */ 559 if (kvm_vm_is_protected(kvm)) 560 kvm_call_hyp_nvhe(__pkvm_vcpu_init_traps, vcpu); 561 562 mutex_lock(&kvm->lock); 563 set_bit(KVM_ARCH_FLAG_HAS_RAN_ONCE, &kvm->arch.flags); 564 mutex_unlock(&kvm->lock); 565 566 return ret; 567 } 568 569 bool kvm_arch_intc_initialized(struct kvm *kvm) 570 { 571 return vgic_initialized(kvm); 572 } 573 574 void kvm_arm_halt_guest(struct kvm *kvm) 575 { 576 unsigned long i; 577 struct kvm_vcpu *vcpu; 578 579 kvm_for_each_vcpu(i, vcpu, kvm) 580 vcpu->arch.pause = true; 581 kvm_make_all_cpus_request(kvm, KVM_REQ_SLEEP); 582 } 583 584 void kvm_arm_resume_guest(struct kvm *kvm) 585 { 586 unsigned long i; 587 struct kvm_vcpu *vcpu; 588 589 kvm_for_each_vcpu(i, vcpu, kvm) { 590 vcpu->arch.pause = false; 591 __kvm_vcpu_wake_up(vcpu); 592 } 593 } 594 595 static void vcpu_req_sleep(struct kvm_vcpu *vcpu) 596 { 597 struct rcuwait *wait = kvm_arch_vcpu_get_wait(vcpu); 598 599 rcuwait_wait_event(wait, 600 (!vcpu->arch.power_off) &&(!vcpu->arch.pause), 601 TASK_INTERRUPTIBLE); 602 603 if (vcpu->arch.power_off || vcpu->arch.pause) { 604 /* Awaken to handle a signal, request we sleep again later. */ 605 kvm_make_request(KVM_REQ_SLEEP, vcpu); 606 } 607 608 /* 609 * Make sure we will observe a potential reset request if we've 610 * observed a change to the power state. Pairs with the smp_wmb() in 611 * kvm_psci_vcpu_on(). 612 */ 613 smp_rmb(); 614 } 615 616 /** 617 * kvm_vcpu_wfi - emulate Wait-For-Interrupt behavior 618 * @vcpu: The VCPU pointer 619 * 620 * Suspend execution of a vCPU until a valid wake event is detected, i.e. until 621 * the vCPU is runnable. The vCPU may or may not be scheduled out, depending 622 * on when a wake event arrives, e.g. there may already be a pending wake event. 623 */ 624 void kvm_vcpu_wfi(struct kvm_vcpu *vcpu) 625 { 626 /* 627 * Sync back the state of the GIC CPU interface so that we have 628 * the latest PMR and group enables. This ensures that 629 * kvm_arch_vcpu_runnable has up-to-date data to decide whether 630 * we have pending interrupts, e.g. when determining if the 631 * vCPU should block. 632 * 633 * For the same reason, we want to tell GICv4 that we need 634 * doorbells to be signalled, should an interrupt become pending. 635 */ 636 preempt_disable(); 637 kvm_vgic_vmcr_sync(vcpu); 638 vgic_v4_put(vcpu, true); 639 preempt_enable(); 640 641 kvm_vcpu_halt(vcpu); 642 kvm_clear_request(KVM_REQ_UNHALT, vcpu); 643 644 preempt_disable(); 645 vgic_v4_load(vcpu); 646 preempt_enable(); 647 } 648 649 static void check_vcpu_requests(struct kvm_vcpu *vcpu) 650 { 651 if (kvm_request_pending(vcpu)) { 652 if (kvm_check_request(KVM_REQ_SLEEP, vcpu)) 653 vcpu_req_sleep(vcpu); 654 655 if (kvm_check_request(KVM_REQ_VCPU_RESET, vcpu)) 656 kvm_reset_vcpu(vcpu); 657 658 /* 659 * Clear IRQ_PENDING requests that were made to guarantee 660 * that a VCPU sees new virtual interrupts. 661 */ 662 kvm_check_request(KVM_REQ_IRQ_PENDING, vcpu); 663 664 if (kvm_check_request(KVM_REQ_RECORD_STEAL, vcpu)) 665 kvm_update_stolen_time(vcpu); 666 667 if (kvm_check_request(KVM_REQ_RELOAD_GICv4, vcpu)) { 668 /* The distributor enable bits were changed */ 669 preempt_disable(); 670 vgic_v4_put(vcpu, false); 671 vgic_v4_load(vcpu); 672 preempt_enable(); 673 } 674 675 if (kvm_check_request(KVM_REQ_RELOAD_PMU, vcpu)) 676 kvm_pmu_handle_pmcr(vcpu, 677 __vcpu_sys_reg(vcpu, PMCR_EL0)); 678 } 679 } 680 681 static bool vcpu_mode_is_bad_32bit(struct kvm_vcpu *vcpu) 682 { 683 if (likely(!vcpu_mode_is_32bit(vcpu))) 684 return false; 685 686 return !system_supports_32bit_el0() || 687 static_branch_unlikely(&arm64_mismatched_32bit_el0); 688 } 689 690 /** 691 * kvm_vcpu_exit_request - returns true if the VCPU should *not* enter the guest 692 * @vcpu: The VCPU pointer 693 * @ret: Pointer to write optional return code 694 * 695 * Returns: true if the VCPU needs to return to a preemptible + interruptible 696 * and skip guest entry. 697 * 698 * This function disambiguates between two different types of exits: exits to a 699 * preemptible + interruptible kernel context and exits to userspace. For an 700 * exit to userspace, this function will write the return code to ret and return 701 * true. For an exit to preemptible + interruptible kernel context (i.e. check 702 * for pending work and re-enter), return true without writing to ret. 703 */ 704 static bool kvm_vcpu_exit_request(struct kvm_vcpu *vcpu, int *ret) 705 { 706 struct kvm_run *run = vcpu->run; 707 708 /* 709 * If we're using a userspace irqchip, then check if we need 710 * to tell a userspace irqchip about timer or PMU level 711 * changes and if so, exit to userspace (the actual level 712 * state gets updated in kvm_timer_update_run and 713 * kvm_pmu_update_run below). 714 */ 715 if (static_branch_unlikely(&userspace_irqchip_in_use)) { 716 if (kvm_timer_should_notify_user(vcpu) || 717 kvm_pmu_should_notify_user(vcpu)) { 718 *ret = -EINTR; 719 run->exit_reason = KVM_EXIT_INTR; 720 return true; 721 } 722 } 723 724 if (unlikely(vcpu_on_unsupported_cpu(vcpu))) { 725 run->exit_reason = KVM_EXIT_FAIL_ENTRY; 726 run->fail_entry.hardware_entry_failure_reason = KVM_EXIT_FAIL_ENTRY_CPU_UNSUPPORTED; 727 run->fail_entry.cpu = smp_processor_id(); 728 *ret = 0; 729 return true; 730 } 731 732 return kvm_request_pending(vcpu) || 733 xfer_to_guest_mode_work_pending(); 734 } 735 736 /* 737 * Actually run the vCPU, entering an RCU extended quiescent state (EQS) while 738 * the vCPU is running. 739 * 740 * This must be noinstr as instrumentation may make use of RCU, and this is not 741 * safe during the EQS. 742 */ 743 static int noinstr kvm_arm_vcpu_enter_exit(struct kvm_vcpu *vcpu) 744 { 745 int ret; 746 747 guest_state_enter_irqoff(); 748 ret = kvm_call_hyp_ret(__kvm_vcpu_run, vcpu); 749 guest_state_exit_irqoff(); 750 751 return ret; 752 } 753 754 /** 755 * kvm_arch_vcpu_ioctl_run - the main VCPU run function to execute guest code 756 * @vcpu: The VCPU pointer 757 * 758 * This function is called through the VCPU_RUN ioctl called from user space. It 759 * will execute VM code in a loop until the time slice for the process is used 760 * or some emulation is needed from user space in which case the function will 761 * return with return value 0 and with the kvm_run structure filled in with the 762 * required data for the requested emulation. 763 */ 764 int kvm_arch_vcpu_ioctl_run(struct kvm_vcpu *vcpu) 765 { 766 struct kvm_run *run = vcpu->run; 767 int ret; 768 769 if (run->exit_reason == KVM_EXIT_MMIO) { 770 ret = kvm_handle_mmio_return(vcpu); 771 if (ret) 772 return ret; 773 } 774 775 vcpu_load(vcpu); 776 777 if (run->immediate_exit) { 778 ret = -EINTR; 779 goto out; 780 } 781 782 kvm_sigset_activate(vcpu); 783 784 ret = 1; 785 run->exit_reason = KVM_EXIT_UNKNOWN; 786 run->flags = 0; 787 while (ret > 0) { 788 /* 789 * Check conditions before entering the guest 790 */ 791 ret = xfer_to_guest_mode_handle_work(vcpu); 792 if (!ret) 793 ret = 1; 794 795 check_vcpu_requests(vcpu); 796 797 /* 798 * Preparing the interrupts to be injected also 799 * involves poking the GIC, which must be done in a 800 * non-preemptible context. 801 */ 802 preempt_disable(); 803 804 /* 805 * The VMID allocator only tracks active VMIDs per 806 * physical CPU, and therefore the VMID allocated may not be 807 * preserved on VMID roll-over if the task was preempted, 808 * making a thread's VMID inactive. So we need to call 809 * kvm_arm_vmid_update() in non-premptible context. 810 */ 811 kvm_arm_vmid_update(&vcpu->arch.hw_mmu->vmid); 812 813 kvm_pmu_flush_hwstate(vcpu); 814 815 local_irq_disable(); 816 817 kvm_vgic_flush_hwstate(vcpu); 818 819 /* 820 * Ensure we set mode to IN_GUEST_MODE after we disable 821 * interrupts and before the final VCPU requests check. 822 * See the comment in kvm_vcpu_exiting_guest_mode() and 823 * Documentation/virt/kvm/vcpu-requests.rst 824 */ 825 smp_store_mb(vcpu->mode, IN_GUEST_MODE); 826 827 if (ret <= 0 || kvm_vcpu_exit_request(vcpu, &ret)) { 828 vcpu->mode = OUTSIDE_GUEST_MODE; 829 isb(); /* Ensure work in x_flush_hwstate is committed */ 830 kvm_pmu_sync_hwstate(vcpu); 831 if (static_branch_unlikely(&userspace_irqchip_in_use)) 832 kvm_timer_sync_user(vcpu); 833 kvm_vgic_sync_hwstate(vcpu); 834 local_irq_enable(); 835 preempt_enable(); 836 continue; 837 } 838 839 kvm_arm_setup_debug(vcpu); 840 kvm_arch_vcpu_ctxflush_fp(vcpu); 841 842 /************************************************************** 843 * Enter the guest 844 */ 845 trace_kvm_entry(*vcpu_pc(vcpu)); 846 guest_timing_enter_irqoff(); 847 848 ret = kvm_arm_vcpu_enter_exit(vcpu); 849 850 vcpu->mode = OUTSIDE_GUEST_MODE; 851 vcpu->stat.exits++; 852 /* 853 * Back from guest 854 *************************************************************/ 855 856 kvm_arm_clear_debug(vcpu); 857 858 /* 859 * We must sync the PMU state before the vgic state so 860 * that the vgic can properly sample the updated state of the 861 * interrupt line. 862 */ 863 kvm_pmu_sync_hwstate(vcpu); 864 865 /* 866 * Sync the vgic state before syncing the timer state because 867 * the timer code needs to know if the virtual timer 868 * interrupts are active. 869 */ 870 kvm_vgic_sync_hwstate(vcpu); 871 872 /* 873 * Sync the timer hardware state before enabling interrupts as 874 * we don't want vtimer interrupts to race with syncing the 875 * timer virtual interrupt state. 876 */ 877 if (static_branch_unlikely(&userspace_irqchip_in_use)) 878 kvm_timer_sync_user(vcpu); 879 880 kvm_arch_vcpu_ctxsync_fp(vcpu); 881 882 /* 883 * We must ensure that any pending interrupts are taken before 884 * we exit guest timing so that timer ticks are accounted as 885 * guest time. Transiently unmask interrupts so that any 886 * pending interrupts are taken. 887 * 888 * Per ARM DDI 0487G.b section D1.13.4, an ISB (or other 889 * context synchronization event) is necessary to ensure that 890 * pending interrupts are taken. 891 */ 892 if (ARM_EXCEPTION_CODE(ret) == ARM_EXCEPTION_IRQ) { 893 local_irq_enable(); 894 isb(); 895 local_irq_disable(); 896 } 897 898 guest_timing_exit_irqoff(); 899 900 local_irq_enable(); 901 902 trace_kvm_exit(ret, kvm_vcpu_trap_get_class(vcpu), *vcpu_pc(vcpu)); 903 904 /* Exit types that need handling before we can be preempted */ 905 handle_exit_early(vcpu, ret); 906 907 preempt_enable(); 908 909 /* 910 * The ARMv8 architecture doesn't give the hypervisor 911 * a mechanism to prevent a guest from dropping to AArch32 EL0 912 * if implemented by the CPU. If we spot the guest in such 913 * state and that we decided it wasn't supposed to do so (like 914 * with the asymmetric AArch32 case), return to userspace with 915 * a fatal error. 916 */ 917 if (vcpu_mode_is_bad_32bit(vcpu)) { 918 /* 919 * As we have caught the guest red-handed, decide that 920 * it isn't fit for purpose anymore by making the vcpu 921 * invalid. The VMM can try and fix it by issuing a 922 * KVM_ARM_VCPU_INIT if it really wants to. 923 */ 924 vcpu->arch.target = -1; 925 ret = ARM_EXCEPTION_IL; 926 } 927 928 ret = handle_exit(vcpu, ret); 929 } 930 931 /* Tell userspace about in-kernel device output levels */ 932 if (unlikely(!irqchip_in_kernel(vcpu->kvm))) { 933 kvm_timer_update_run(vcpu); 934 kvm_pmu_update_run(vcpu); 935 } 936 937 kvm_sigset_deactivate(vcpu); 938 939 out: 940 /* 941 * In the unlikely event that we are returning to userspace 942 * with pending exceptions or PC adjustment, commit these 943 * adjustments in order to give userspace a consistent view of 944 * the vcpu state. Note that this relies on __kvm_adjust_pc() 945 * being preempt-safe on VHE. 946 */ 947 if (unlikely(vcpu->arch.flags & (KVM_ARM64_PENDING_EXCEPTION | 948 KVM_ARM64_INCREMENT_PC))) 949 kvm_call_hyp(__kvm_adjust_pc, vcpu); 950 951 vcpu_put(vcpu); 952 return ret; 953 } 954 955 static int vcpu_interrupt_line(struct kvm_vcpu *vcpu, int number, bool level) 956 { 957 int bit_index; 958 bool set; 959 unsigned long *hcr; 960 961 if (number == KVM_ARM_IRQ_CPU_IRQ) 962 bit_index = __ffs(HCR_VI); 963 else /* KVM_ARM_IRQ_CPU_FIQ */ 964 bit_index = __ffs(HCR_VF); 965 966 hcr = vcpu_hcr(vcpu); 967 if (level) 968 set = test_and_set_bit(bit_index, hcr); 969 else 970 set = test_and_clear_bit(bit_index, hcr); 971 972 /* 973 * If we didn't change anything, no need to wake up or kick other CPUs 974 */ 975 if (set == level) 976 return 0; 977 978 /* 979 * The vcpu irq_lines field was updated, wake up sleeping VCPUs and 980 * trigger a world-switch round on the running physical CPU to set the 981 * virtual IRQ/FIQ fields in the HCR appropriately. 982 */ 983 kvm_make_request(KVM_REQ_IRQ_PENDING, vcpu); 984 kvm_vcpu_kick(vcpu); 985 986 return 0; 987 } 988 989 int kvm_vm_ioctl_irq_line(struct kvm *kvm, struct kvm_irq_level *irq_level, 990 bool line_status) 991 { 992 u32 irq = irq_level->irq; 993 unsigned int irq_type, vcpu_idx, irq_num; 994 int nrcpus = atomic_read(&kvm->online_vcpus); 995 struct kvm_vcpu *vcpu = NULL; 996 bool level = irq_level->level; 997 998 irq_type = (irq >> KVM_ARM_IRQ_TYPE_SHIFT) & KVM_ARM_IRQ_TYPE_MASK; 999 vcpu_idx = (irq >> KVM_ARM_IRQ_VCPU_SHIFT) & KVM_ARM_IRQ_VCPU_MASK; 1000 vcpu_idx += ((irq >> KVM_ARM_IRQ_VCPU2_SHIFT) & KVM_ARM_IRQ_VCPU2_MASK) * (KVM_ARM_IRQ_VCPU_MASK + 1); 1001 irq_num = (irq >> KVM_ARM_IRQ_NUM_SHIFT) & KVM_ARM_IRQ_NUM_MASK; 1002 1003 trace_kvm_irq_line(irq_type, vcpu_idx, irq_num, irq_level->level); 1004 1005 switch (irq_type) { 1006 case KVM_ARM_IRQ_TYPE_CPU: 1007 if (irqchip_in_kernel(kvm)) 1008 return -ENXIO; 1009 1010 if (vcpu_idx >= nrcpus) 1011 return -EINVAL; 1012 1013 vcpu = kvm_get_vcpu(kvm, vcpu_idx); 1014 if (!vcpu) 1015 return -EINVAL; 1016 1017 if (irq_num > KVM_ARM_IRQ_CPU_FIQ) 1018 return -EINVAL; 1019 1020 return vcpu_interrupt_line(vcpu, irq_num, level); 1021 case KVM_ARM_IRQ_TYPE_PPI: 1022 if (!irqchip_in_kernel(kvm)) 1023 return -ENXIO; 1024 1025 if (vcpu_idx >= nrcpus) 1026 return -EINVAL; 1027 1028 vcpu = kvm_get_vcpu(kvm, vcpu_idx); 1029 if (!vcpu) 1030 return -EINVAL; 1031 1032 if (irq_num < VGIC_NR_SGIS || irq_num >= VGIC_NR_PRIVATE_IRQS) 1033 return -EINVAL; 1034 1035 return kvm_vgic_inject_irq(kvm, vcpu->vcpu_id, irq_num, level, NULL); 1036 case KVM_ARM_IRQ_TYPE_SPI: 1037 if (!irqchip_in_kernel(kvm)) 1038 return -ENXIO; 1039 1040 if (irq_num < VGIC_NR_PRIVATE_IRQS) 1041 return -EINVAL; 1042 1043 return kvm_vgic_inject_irq(kvm, 0, irq_num, level, NULL); 1044 } 1045 1046 return -EINVAL; 1047 } 1048 1049 static int kvm_vcpu_set_target(struct kvm_vcpu *vcpu, 1050 const struct kvm_vcpu_init *init) 1051 { 1052 unsigned int i, ret; 1053 u32 phys_target = kvm_target_cpu(); 1054 1055 if (init->target != phys_target) 1056 return -EINVAL; 1057 1058 /* 1059 * Secondary and subsequent calls to KVM_ARM_VCPU_INIT must 1060 * use the same target. 1061 */ 1062 if (vcpu->arch.target != -1 && vcpu->arch.target != init->target) 1063 return -EINVAL; 1064 1065 /* -ENOENT for unknown features, -EINVAL for invalid combinations. */ 1066 for (i = 0; i < sizeof(init->features) * 8; i++) { 1067 bool set = (init->features[i / 32] & (1 << (i % 32))); 1068 1069 if (set && i >= KVM_VCPU_MAX_FEATURES) 1070 return -ENOENT; 1071 1072 /* 1073 * Secondary and subsequent calls to KVM_ARM_VCPU_INIT must 1074 * use the same feature set. 1075 */ 1076 if (vcpu->arch.target != -1 && i < KVM_VCPU_MAX_FEATURES && 1077 test_bit(i, vcpu->arch.features) != set) 1078 return -EINVAL; 1079 1080 if (set) 1081 set_bit(i, vcpu->arch.features); 1082 } 1083 1084 vcpu->arch.target = phys_target; 1085 1086 /* Now we know what it is, we can reset it. */ 1087 ret = kvm_reset_vcpu(vcpu); 1088 if (ret) { 1089 vcpu->arch.target = -1; 1090 bitmap_zero(vcpu->arch.features, KVM_VCPU_MAX_FEATURES); 1091 } 1092 1093 return ret; 1094 } 1095 1096 static int kvm_arch_vcpu_ioctl_vcpu_init(struct kvm_vcpu *vcpu, 1097 struct kvm_vcpu_init *init) 1098 { 1099 int ret; 1100 1101 ret = kvm_vcpu_set_target(vcpu, init); 1102 if (ret) 1103 return ret; 1104 1105 /* 1106 * Ensure a rebooted VM will fault in RAM pages and detect if the 1107 * guest MMU is turned off and flush the caches as needed. 1108 * 1109 * S2FWB enforces all memory accesses to RAM being cacheable, 1110 * ensuring that the data side is always coherent. We still 1111 * need to invalidate the I-cache though, as FWB does *not* 1112 * imply CTR_EL0.DIC. 1113 */ 1114 if (vcpu_has_run_once(vcpu)) { 1115 if (!cpus_have_final_cap(ARM64_HAS_STAGE2_FWB)) 1116 stage2_unmap_vm(vcpu->kvm); 1117 else 1118 icache_inval_all_pou(); 1119 } 1120 1121 vcpu_reset_hcr(vcpu); 1122 vcpu->arch.cptr_el2 = CPTR_EL2_DEFAULT; 1123 1124 /* 1125 * Handle the "start in power-off" case. 1126 */ 1127 if (test_bit(KVM_ARM_VCPU_POWER_OFF, vcpu->arch.features)) 1128 vcpu_power_off(vcpu); 1129 else 1130 vcpu->arch.power_off = false; 1131 1132 return 0; 1133 } 1134 1135 static int kvm_arm_vcpu_set_attr(struct kvm_vcpu *vcpu, 1136 struct kvm_device_attr *attr) 1137 { 1138 int ret = -ENXIO; 1139 1140 switch (attr->group) { 1141 default: 1142 ret = kvm_arm_vcpu_arch_set_attr(vcpu, attr); 1143 break; 1144 } 1145 1146 return ret; 1147 } 1148 1149 static int kvm_arm_vcpu_get_attr(struct kvm_vcpu *vcpu, 1150 struct kvm_device_attr *attr) 1151 { 1152 int ret = -ENXIO; 1153 1154 switch (attr->group) { 1155 default: 1156 ret = kvm_arm_vcpu_arch_get_attr(vcpu, attr); 1157 break; 1158 } 1159 1160 return ret; 1161 } 1162 1163 static int kvm_arm_vcpu_has_attr(struct kvm_vcpu *vcpu, 1164 struct kvm_device_attr *attr) 1165 { 1166 int ret = -ENXIO; 1167 1168 switch (attr->group) { 1169 default: 1170 ret = kvm_arm_vcpu_arch_has_attr(vcpu, attr); 1171 break; 1172 } 1173 1174 return ret; 1175 } 1176 1177 static int kvm_arm_vcpu_get_events(struct kvm_vcpu *vcpu, 1178 struct kvm_vcpu_events *events) 1179 { 1180 memset(events, 0, sizeof(*events)); 1181 1182 return __kvm_arm_vcpu_get_events(vcpu, events); 1183 } 1184 1185 static int kvm_arm_vcpu_set_events(struct kvm_vcpu *vcpu, 1186 struct kvm_vcpu_events *events) 1187 { 1188 int i; 1189 1190 /* check whether the reserved field is zero */ 1191 for (i = 0; i < ARRAY_SIZE(events->reserved); i++) 1192 if (events->reserved[i]) 1193 return -EINVAL; 1194 1195 /* check whether the pad field is zero */ 1196 for (i = 0; i < ARRAY_SIZE(events->exception.pad); i++) 1197 if (events->exception.pad[i]) 1198 return -EINVAL; 1199 1200 return __kvm_arm_vcpu_set_events(vcpu, events); 1201 } 1202 1203 long kvm_arch_vcpu_ioctl(struct file *filp, 1204 unsigned int ioctl, unsigned long arg) 1205 { 1206 struct kvm_vcpu *vcpu = filp->private_data; 1207 void __user *argp = (void __user *)arg; 1208 struct kvm_device_attr attr; 1209 long r; 1210 1211 switch (ioctl) { 1212 case KVM_ARM_VCPU_INIT: { 1213 struct kvm_vcpu_init init; 1214 1215 r = -EFAULT; 1216 if (copy_from_user(&init, argp, sizeof(init))) 1217 break; 1218 1219 r = kvm_arch_vcpu_ioctl_vcpu_init(vcpu, &init); 1220 break; 1221 } 1222 case KVM_SET_ONE_REG: 1223 case KVM_GET_ONE_REG: { 1224 struct kvm_one_reg reg; 1225 1226 r = -ENOEXEC; 1227 if (unlikely(!kvm_vcpu_initialized(vcpu))) 1228 break; 1229 1230 r = -EFAULT; 1231 if (copy_from_user(®, argp, sizeof(reg))) 1232 break; 1233 1234 /* 1235 * We could owe a reset due to PSCI. Handle the pending reset 1236 * here to ensure userspace register accesses are ordered after 1237 * the reset. 1238 */ 1239 if (kvm_check_request(KVM_REQ_VCPU_RESET, vcpu)) 1240 kvm_reset_vcpu(vcpu); 1241 1242 if (ioctl == KVM_SET_ONE_REG) 1243 r = kvm_arm_set_reg(vcpu, ®); 1244 else 1245 r = kvm_arm_get_reg(vcpu, ®); 1246 break; 1247 } 1248 case KVM_GET_REG_LIST: { 1249 struct kvm_reg_list __user *user_list = argp; 1250 struct kvm_reg_list reg_list; 1251 unsigned n; 1252 1253 r = -ENOEXEC; 1254 if (unlikely(!kvm_vcpu_initialized(vcpu))) 1255 break; 1256 1257 r = -EPERM; 1258 if (!kvm_arm_vcpu_is_finalized(vcpu)) 1259 break; 1260 1261 r = -EFAULT; 1262 if (copy_from_user(®_list, user_list, sizeof(reg_list))) 1263 break; 1264 n = reg_list.n; 1265 reg_list.n = kvm_arm_num_regs(vcpu); 1266 if (copy_to_user(user_list, ®_list, sizeof(reg_list))) 1267 break; 1268 r = -E2BIG; 1269 if (n < reg_list.n) 1270 break; 1271 r = kvm_arm_copy_reg_indices(vcpu, user_list->reg); 1272 break; 1273 } 1274 case KVM_SET_DEVICE_ATTR: { 1275 r = -EFAULT; 1276 if (copy_from_user(&attr, argp, sizeof(attr))) 1277 break; 1278 r = kvm_arm_vcpu_set_attr(vcpu, &attr); 1279 break; 1280 } 1281 case KVM_GET_DEVICE_ATTR: { 1282 r = -EFAULT; 1283 if (copy_from_user(&attr, argp, sizeof(attr))) 1284 break; 1285 r = kvm_arm_vcpu_get_attr(vcpu, &attr); 1286 break; 1287 } 1288 case KVM_HAS_DEVICE_ATTR: { 1289 r = -EFAULT; 1290 if (copy_from_user(&attr, argp, sizeof(attr))) 1291 break; 1292 r = kvm_arm_vcpu_has_attr(vcpu, &attr); 1293 break; 1294 } 1295 case KVM_GET_VCPU_EVENTS: { 1296 struct kvm_vcpu_events events; 1297 1298 if (kvm_arm_vcpu_get_events(vcpu, &events)) 1299 return -EINVAL; 1300 1301 if (copy_to_user(argp, &events, sizeof(events))) 1302 return -EFAULT; 1303 1304 return 0; 1305 } 1306 case KVM_SET_VCPU_EVENTS: { 1307 struct kvm_vcpu_events events; 1308 1309 if (copy_from_user(&events, argp, sizeof(events))) 1310 return -EFAULT; 1311 1312 return kvm_arm_vcpu_set_events(vcpu, &events); 1313 } 1314 case KVM_ARM_VCPU_FINALIZE: { 1315 int what; 1316 1317 if (!kvm_vcpu_initialized(vcpu)) 1318 return -ENOEXEC; 1319 1320 if (get_user(what, (const int __user *)argp)) 1321 return -EFAULT; 1322 1323 return kvm_arm_vcpu_finalize(vcpu, what); 1324 } 1325 default: 1326 r = -EINVAL; 1327 } 1328 1329 return r; 1330 } 1331 1332 void kvm_arch_sync_dirty_log(struct kvm *kvm, struct kvm_memory_slot *memslot) 1333 { 1334 1335 } 1336 1337 void kvm_arch_flush_remote_tlbs_memslot(struct kvm *kvm, 1338 const struct kvm_memory_slot *memslot) 1339 { 1340 kvm_flush_remote_tlbs(kvm); 1341 } 1342 1343 static int kvm_vm_ioctl_set_device_addr(struct kvm *kvm, 1344 struct kvm_arm_device_addr *dev_addr) 1345 { 1346 unsigned long dev_id, type; 1347 1348 dev_id = (dev_addr->id & KVM_ARM_DEVICE_ID_MASK) >> 1349 KVM_ARM_DEVICE_ID_SHIFT; 1350 type = (dev_addr->id & KVM_ARM_DEVICE_TYPE_MASK) >> 1351 KVM_ARM_DEVICE_TYPE_SHIFT; 1352 1353 switch (dev_id) { 1354 case KVM_ARM_DEVICE_VGIC_V2: 1355 if (!vgic_present) 1356 return -ENXIO; 1357 return kvm_vgic_addr(kvm, type, &dev_addr->addr, true); 1358 default: 1359 return -ENODEV; 1360 } 1361 } 1362 1363 long kvm_arch_vm_ioctl(struct file *filp, 1364 unsigned int ioctl, unsigned long arg) 1365 { 1366 struct kvm *kvm = filp->private_data; 1367 void __user *argp = (void __user *)arg; 1368 1369 switch (ioctl) { 1370 case KVM_CREATE_IRQCHIP: { 1371 int ret; 1372 if (!vgic_present) 1373 return -ENXIO; 1374 mutex_lock(&kvm->lock); 1375 ret = kvm_vgic_create(kvm, KVM_DEV_TYPE_ARM_VGIC_V2); 1376 mutex_unlock(&kvm->lock); 1377 return ret; 1378 } 1379 case KVM_ARM_SET_DEVICE_ADDR: { 1380 struct kvm_arm_device_addr dev_addr; 1381 1382 if (copy_from_user(&dev_addr, argp, sizeof(dev_addr))) 1383 return -EFAULT; 1384 return kvm_vm_ioctl_set_device_addr(kvm, &dev_addr); 1385 } 1386 case KVM_ARM_PREFERRED_TARGET: { 1387 struct kvm_vcpu_init init; 1388 1389 kvm_vcpu_preferred_target(&init); 1390 1391 if (copy_to_user(argp, &init, sizeof(init))) 1392 return -EFAULT; 1393 1394 return 0; 1395 } 1396 case KVM_ARM_MTE_COPY_TAGS: { 1397 struct kvm_arm_copy_mte_tags copy_tags; 1398 1399 if (copy_from_user(©_tags, argp, sizeof(copy_tags))) 1400 return -EFAULT; 1401 return kvm_vm_ioctl_mte_copy_tags(kvm, ©_tags); 1402 } 1403 default: 1404 return -EINVAL; 1405 } 1406 } 1407 1408 static unsigned long nvhe_percpu_size(void) 1409 { 1410 return (unsigned long)CHOOSE_NVHE_SYM(__per_cpu_end) - 1411 (unsigned long)CHOOSE_NVHE_SYM(__per_cpu_start); 1412 } 1413 1414 static unsigned long nvhe_percpu_order(void) 1415 { 1416 unsigned long size = nvhe_percpu_size(); 1417 1418 return size ? get_order(size) : 0; 1419 } 1420 1421 /* A lookup table holding the hypervisor VA for each vector slot */ 1422 static void *hyp_spectre_vector_selector[BP_HARDEN_EL2_SLOTS]; 1423 1424 static void kvm_init_vector_slot(void *base, enum arm64_hyp_spectre_vector slot) 1425 { 1426 hyp_spectre_vector_selector[slot] = __kvm_vector_slot2addr(base, slot); 1427 } 1428 1429 static int kvm_init_vector_slots(void) 1430 { 1431 int err; 1432 void *base; 1433 1434 base = kern_hyp_va(kvm_ksym_ref(__kvm_hyp_vector)); 1435 kvm_init_vector_slot(base, HYP_VECTOR_DIRECT); 1436 1437 base = kern_hyp_va(kvm_ksym_ref(__bp_harden_hyp_vecs)); 1438 kvm_init_vector_slot(base, HYP_VECTOR_SPECTRE_DIRECT); 1439 1440 if (kvm_system_needs_idmapped_vectors() && 1441 !is_protected_kvm_enabled()) { 1442 err = create_hyp_exec_mappings(__pa_symbol(__bp_harden_hyp_vecs), 1443 __BP_HARDEN_HYP_VECS_SZ, &base); 1444 if (err) 1445 return err; 1446 } 1447 1448 kvm_init_vector_slot(base, HYP_VECTOR_INDIRECT); 1449 kvm_init_vector_slot(base, HYP_VECTOR_SPECTRE_INDIRECT); 1450 return 0; 1451 } 1452 1453 static void cpu_prepare_hyp_mode(int cpu) 1454 { 1455 struct kvm_nvhe_init_params *params = per_cpu_ptr_nvhe_sym(kvm_init_params, cpu); 1456 unsigned long tcr; 1457 1458 /* 1459 * Calculate the raw per-cpu offset without a translation from the 1460 * kernel's mapping to the linear mapping, and store it in tpidr_el2 1461 * so that we can use adr_l to access per-cpu variables in EL2. 1462 * Also drop the KASAN tag which gets in the way... 1463 */ 1464 params->tpidr_el2 = (unsigned long)kasan_reset_tag(per_cpu_ptr_nvhe_sym(__per_cpu_start, cpu)) - 1465 (unsigned long)kvm_ksym_ref(CHOOSE_NVHE_SYM(__per_cpu_start)); 1466 1467 params->mair_el2 = read_sysreg(mair_el1); 1468 1469 /* 1470 * The ID map may be configured to use an extended virtual address 1471 * range. This is only the case if system RAM is out of range for the 1472 * currently configured page size and VA_BITS, in which case we will 1473 * also need the extended virtual range for the HYP ID map, or we won't 1474 * be able to enable the EL2 MMU. 1475 * 1476 * However, at EL2, there is only one TTBR register, and we can't switch 1477 * between translation tables *and* update TCR_EL2.T0SZ at the same 1478 * time. Bottom line: we need to use the extended range with *both* our 1479 * translation tables. 1480 * 1481 * So use the same T0SZ value we use for the ID map. 1482 */ 1483 tcr = (read_sysreg(tcr_el1) & TCR_EL2_MASK) | TCR_EL2_RES1; 1484 tcr &= ~TCR_T0SZ_MASK; 1485 tcr |= (idmap_t0sz & GENMASK(TCR_TxSZ_WIDTH - 1, 0)) << TCR_T0SZ_OFFSET; 1486 params->tcr_el2 = tcr; 1487 1488 params->stack_hyp_va = kern_hyp_va(per_cpu(kvm_arm_hyp_stack_page, cpu) + PAGE_SIZE); 1489 params->pgd_pa = kvm_mmu_get_httbr(); 1490 if (is_protected_kvm_enabled()) 1491 params->hcr_el2 = HCR_HOST_NVHE_PROTECTED_FLAGS; 1492 else 1493 params->hcr_el2 = HCR_HOST_NVHE_FLAGS; 1494 params->vttbr = params->vtcr = 0; 1495 1496 /* 1497 * Flush the init params from the data cache because the struct will 1498 * be read while the MMU is off. 1499 */ 1500 kvm_flush_dcache_to_poc(params, sizeof(*params)); 1501 } 1502 1503 static void hyp_install_host_vector(void) 1504 { 1505 struct kvm_nvhe_init_params *params; 1506 struct arm_smccc_res res; 1507 1508 /* Switch from the HYP stub to our own HYP init vector */ 1509 __hyp_set_vectors(kvm_get_idmap_vector()); 1510 1511 /* 1512 * Call initialization code, and switch to the full blown HYP code. 1513 * If the cpucaps haven't been finalized yet, something has gone very 1514 * wrong, and hyp will crash and burn when it uses any 1515 * cpus_have_const_cap() wrapper. 1516 */ 1517 BUG_ON(!system_capabilities_finalized()); 1518 params = this_cpu_ptr_nvhe_sym(kvm_init_params); 1519 arm_smccc_1_1_hvc(KVM_HOST_SMCCC_FUNC(__kvm_hyp_init), virt_to_phys(params), &res); 1520 WARN_ON(res.a0 != SMCCC_RET_SUCCESS); 1521 } 1522 1523 static void cpu_init_hyp_mode(void) 1524 { 1525 hyp_install_host_vector(); 1526 1527 /* 1528 * Disabling SSBD on a non-VHE system requires us to enable SSBS 1529 * at EL2. 1530 */ 1531 if (this_cpu_has_cap(ARM64_SSBS) && 1532 arm64_get_spectre_v4_state() == SPECTRE_VULNERABLE) { 1533 kvm_call_hyp_nvhe(__kvm_enable_ssbs); 1534 } 1535 } 1536 1537 static void cpu_hyp_reset(void) 1538 { 1539 if (!is_kernel_in_hyp_mode()) 1540 __hyp_reset_vectors(); 1541 } 1542 1543 /* 1544 * EL2 vectors can be mapped and rerouted in a number of ways, 1545 * depending on the kernel configuration and CPU present: 1546 * 1547 * - If the CPU is affected by Spectre-v2, the hardening sequence is 1548 * placed in one of the vector slots, which is executed before jumping 1549 * to the real vectors. 1550 * 1551 * - If the CPU also has the ARM64_SPECTRE_V3A cap, the slot 1552 * containing the hardening sequence is mapped next to the idmap page, 1553 * and executed before jumping to the real vectors. 1554 * 1555 * - If the CPU only has the ARM64_SPECTRE_V3A cap, then an 1556 * empty slot is selected, mapped next to the idmap page, and 1557 * executed before jumping to the real vectors. 1558 * 1559 * Note that ARM64_SPECTRE_V3A is somewhat incompatible with 1560 * VHE, as we don't have hypervisor-specific mappings. If the system 1561 * is VHE and yet selects this capability, it will be ignored. 1562 */ 1563 static void cpu_set_hyp_vector(void) 1564 { 1565 struct bp_hardening_data *data = this_cpu_ptr(&bp_hardening_data); 1566 void *vector = hyp_spectre_vector_selector[data->slot]; 1567 1568 if (!is_protected_kvm_enabled()) 1569 *this_cpu_ptr_hyp_sym(kvm_hyp_vector) = (unsigned long)vector; 1570 else 1571 kvm_call_hyp_nvhe(__pkvm_cpu_set_vector, data->slot); 1572 } 1573 1574 static void cpu_hyp_init_context(void) 1575 { 1576 kvm_init_host_cpu_context(&this_cpu_ptr_hyp_sym(kvm_host_data)->host_ctxt); 1577 1578 if (!is_kernel_in_hyp_mode()) 1579 cpu_init_hyp_mode(); 1580 } 1581 1582 static void cpu_hyp_init_features(void) 1583 { 1584 cpu_set_hyp_vector(); 1585 kvm_arm_init_debug(); 1586 1587 if (is_kernel_in_hyp_mode()) 1588 kvm_timer_init_vhe(); 1589 1590 if (vgic_present) 1591 kvm_vgic_init_cpu_hardware(); 1592 } 1593 1594 static void cpu_hyp_reinit(void) 1595 { 1596 cpu_hyp_reset(); 1597 cpu_hyp_init_context(); 1598 cpu_hyp_init_features(); 1599 } 1600 1601 static void _kvm_arch_hardware_enable(void *discard) 1602 { 1603 if (!__this_cpu_read(kvm_arm_hardware_enabled)) { 1604 cpu_hyp_reinit(); 1605 __this_cpu_write(kvm_arm_hardware_enabled, 1); 1606 } 1607 } 1608 1609 int kvm_arch_hardware_enable(void) 1610 { 1611 _kvm_arch_hardware_enable(NULL); 1612 return 0; 1613 } 1614 1615 static void _kvm_arch_hardware_disable(void *discard) 1616 { 1617 if (__this_cpu_read(kvm_arm_hardware_enabled)) { 1618 cpu_hyp_reset(); 1619 __this_cpu_write(kvm_arm_hardware_enabled, 0); 1620 } 1621 } 1622 1623 void kvm_arch_hardware_disable(void) 1624 { 1625 if (!is_protected_kvm_enabled()) 1626 _kvm_arch_hardware_disable(NULL); 1627 } 1628 1629 #ifdef CONFIG_CPU_PM 1630 static int hyp_init_cpu_pm_notifier(struct notifier_block *self, 1631 unsigned long cmd, 1632 void *v) 1633 { 1634 /* 1635 * kvm_arm_hardware_enabled is left with its old value over 1636 * PM_ENTER->PM_EXIT. It is used to indicate PM_EXIT should 1637 * re-enable hyp. 1638 */ 1639 switch (cmd) { 1640 case CPU_PM_ENTER: 1641 if (__this_cpu_read(kvm_arm_hardware_enabled)) 1642 /* 1643 * don't update kvm_arm_hardware_enabled here 1644 * so that the hardware will be re-enabled 1645 * when we resume. See below. 1646 */ 1647 cpu_hyp_reset(); 1648 1649 return NOTIFY_OK; 1650 case CPU_PM_ENTER_FAILED: 1651 case CPU_PM_EXIT: 1652 if (__this_cpu_read(kvm_arm_hardware_enabled)) 1653 /* The hardware was enabled before suspend. */ 1654 cpu_hyp_reinit(); 1655 1656 return NOTIFY_OK; 1657 1658 default: 1659 return NOTIFY_DONE; 1660 } 1661 } 1662 1663 static struct notifier_block hyp_init_cpu_pm_nb = { 1664 .notifier_call = hyp_init_cpu_pm_notifier, 1665 }; 1666 1667 static void hyp_cpu_pm_init(void) 1668 { 1669 if (!is_protected_kvm_enabled()) 1670 cpu_pm_register_notifier(&hyp_init_cpu_pm_nb); 1671 } 1672 static void hyp_cpu_pm_exit(void) 1673 { 1674 if (!is_protected_kvm_enabled()) 1675 cpu_pm_unregister_notifier(&hyp_init_cpu_pm_nb); 1676 } 1677 #else 1678 static inline void hyp_cpu_pm_init(void) 1679 { 1680 } 1681 static inline void hyp_cpu_pm_exit(void) 1682 { 1683 } 1684 #endif 1685 1686 static void init_cpu_logical_map(void) 1687 { 1688 unsigned int cpu; 1689 1690 /* 1691 * Copy the MPIDR <-> logical CPU ID mapping to hyp. 1692 * Only copy the set of online CPUs whose features have been checked 1693 * against the finalized system capabilities. The hypervisor will not 1694 * allow any other CPUs from the `possible` set to boot. 1695 */ 1696 for_each_online_cpu(cpu) 1697 hyp_cpu_logical_map[cpu] = cpu_logical_map(cpu); 1698 } 1699 1700 #define init_psci_0_1_impl_state(config, what) \ 1701 config.psci_0_1_ ## what ## _implemented = psci_ops.what 1702 1703 static bool init_psci_relay(void) 1704 { 1705 /* 1706 * If PSCI has not been initialized, protected KVM cannot install 1707 * itself on newly booted CPUs. 1708 */ 1709 if (!psci_ops.get_version) { 1710 kvm_err("Cannot initialize protected mode without PSCI\n"); 1711 return false; 1712 } 1713 1714 kvm_host_psci_config.version = psci_ops.get_version(); 1715 1716 if (kvm_host_psci_config.version == PSCI_VERSION(0, 1)) { 1717 kvm_host_psci_config.function_ids_0_1 = get_psci_0_1_function_ids(); 1718 init_psci_0_1_impl_state(kvm_host_psci_config, cpu_suspend); 1719 init_psci_0_1_impl_state(kvm_host_psci_config, cpu_on); 1720 init_psci_0_1_impl_state(kvm_host_psci_config, cpu_off); 1721 init_psci_0_1_impl_state(kvm_host_psci_config, migrate); 1722 } 1723 return true; 1724 } 1725 1726 static int init_subsystems(void) 1727 { 1728 int err = 0; 1729 1730 /* 1731 * Enable hardware so that subsystem initialisation can access EL2. 1732 */ 1733 on_each_cpu(_kvm_arch_hardware_enable, NULL, 1); 1734 1735 /* 1736 * Register CPU lower-power notifier 1737 */ 1738 hyp_cpu_pm_init(); 1739 1740 /* 1741 * Init HYP view of VGIC 1742 */ 1743 err = kvm_vgic_hyp_init(); 1744 switch (err) { 1745 case 0: 1746 vgic_present = true; 1747 break; 1748 case -ENODEV: 1749 case -ENXIO: 1750 vgic_present = false; 1751 err = 0; 1752 break; 1753 default: 1754 goto out; 1755 } 1756 1757 /* 1758 * Init HYP architected timer support 1759 */ 1760 err = kvm_timer_hyp_init(vgic_present); 1761 if (err) 1762 goto out; 1763 1764 kvm_register_perf_callbacks(NULL); 1765 1766 kvm_sys_reg_table_init(); 1767 1768 out: 1769 if (err || !is_protected_kvm_enabled()) 1770 on_each_cpu(_kvm_arch_hardware_disable, NULL, 1); 1771 1772 return err; 1773 } 1774 1775 static void teardown_hyp_mode(void) 1776 { 1777 int cpu; 1778 1779 free_hyp_pgds(); 1780 for_each_possible_cpu(cpu) { 1781 free_page(per_cpu(kvm_arm_hyp_stack_page, cpu)); 1782 free_pages(kvm_arm_hyp_percpu_base[cpu], nvhe_percpu_order()); 1783 } 1784 } 1785 1786 static int do_pkvm_init(u32 hyp_va_bits) 1787 { 1788 void *per_cpu_base = kvm_ksym_ref(kvm_arm_hyp_percpu_base); 1789 int ret; 1790 1791 preempt_disable(); 1792 cpu_hyp_init_context(); 1793 ret = kvm_call_hyp_nvhe(__pkvm_init, hyp_mem_base, hyp_mem_size, 1794 num_possible_cpus(), kern_hyp_va(per_cpu_base), 1795 hyp_va_bits); 1796 cpu_hyp_init_features(); 1797 1798 /* 1799 * The stub hypercalls are now disabled, so set our local flag to 1800 * prevent a later re-init attempt in kvm_arch_hardware_enable(). 1801 */ 1802 __this_cpu_write(kvm_arm_hardware_enabled, 1); 1803 preempt_enable(); 1804 1805 return ret; 1806 } 1807 1808 static int kvm_hyp_init_protection(u32 hyp_va_bits) 1809 { 1810 void *addr = phys_to_virt(hyp_mem_base); 1811 int ret; 1812 1813 kvm_nvhe_sym(id_aa64pfr0_el1_sys_val) = read_sanitised_ftr_reg(SYS_ID_AA64PFR0_EL1); 1814 kvm_nvhe_sym(id_aa64pfr1_el1_sys_val) = read_sanitised_ftr_reg(SYS_ID_AA64PFR1_EL1); 1815 kvm_nvhe_sym(id_aa64isar0_el1_sys_val) = read_sanitised_ftr_reg(SYS_ID_AA64ISAR0_EL1); 1816 kvm_nvhe_sym(id_aa64isar1_el1_sys_val) = read_sanitised_ftr_reg(SYS_ID_AA64ISAR1_EL1); 1817 kvm_nvhe_sym(id_aa64isar2_el1_sys_val) = read_sanitised_ftr_reg(SYS_ID_AA64ISAR2_EL1); 1818 kvm_nvhe_sym(id_aa64mmfr0_el1_sys_val) = read_sanitised_ftr_reg(SYS_ID_AA64MMFR0_EL1); 1819 kvm_nvhe_sym(id_aa64mmfr1_el1_sys_val) = read_sanitised_ftr_reg(SYS_ID_AA64MMFR1_EL1); 1820 kvm_nvhe_sym(id_aa64mmfr2_el1_sys_val) = read_sanitised_ftr_reg(SYS_ID_AA64MMFR2_EL1); 1821 1822 ret = create_hyp_mappings(addr, addr + hyp_mem_size, PAGE_HYP); 1823 if (ret) 1824 return ret; 1825 1826 ret = do_pkvm_init(hyp_va_bits); 1827 if (ret) 1828 return ret; 1829 1830 free_hyp_pgds(); 1831 1832 return 0; 1833 } 1834 1835 /** 1836 * Inits Hyp-mode on all online CPUs 1837 */ 1838 static int init_hyp_mode(void) 1839 { 1840 u32 hyp_va_bits; 1841 int cpu; 1842 int err = -ENOMEM; 1843 1844 /* 1845 * The protected Hyp-mode cannot be initialized if the memory pool 1846 * allocation has failed. 1847 */ 1848 if (is_protected_kvm_enabled() && !hyp_mem_base) 1849 goto out_err; 1850 1851 /* 1852 * Allocate Hyp PGD and setup Hyp identity mapping 1853 */ 1854 err = kvm_mmu_init(&hyp_va_bits); 1855 if (err) 1856 goto out_err; 1857 1858 /* 1859 * Allocate stack pages for Hypervisor-mode 1860 */ 1861 for_each_possible_cpu(cpu) { 1862 unsigned long stack_page; 1863 1864 stack_page = __get_free_page(GFP_KERNEL); 1865 if (!stack_page) { 1866 err = -ENOMEM; 1867 goto out_err; 1868 } 1869 1870 per_cpu(kvm_arm_hyp_stack_page, cpu) = stack_page; 1871 } 1872 1873 /* 1874 * Allocate and initialize pages for Hypervisor-mode percpu regions. 1875 */ 1876 for_each_possible_cpu(cpu) { 1877 struct page *page; 1878 void *page_addr; 1879 1880 page = alloc_pages(GFP_KERNEL, nvhe_percpu_order()); 1881 if (!page) { 1882 err = -ENOMEM; 1883 goto out_err; 1884 } 1885 1886 page_addr = page_address(page); 1887 memcpy(page_addr, CHOOSE_NVHE_SYM(__per_cpu_start), nvhe_percpu_size()); 1888 kvm_arm_hyp_percpu_base[cpu] = (unsigned long)page_addr; 1889 } 1890 1891 /* 1892 * Map the Hyp-code called directly from the host 1893 */ 1894 err = create_hyp_mappings(kvm_ksym_ref(__hyp_text_start), 1895 kvm_ksym_ref(__hyp_text_end), PAGE_HYP_EXEC); 1896 if (err) { 1897 kvm_err("Cannot map world-switch code\n"); 1898 goto out_err; 1899 } 1900 1901 err = create_hyp_mappings(kvm_ksym_ref(__hyp_rodata_start), 1902 kvm_ksym_ref(__hyp_rodata_end), PAGE_HYP_RO); 1903 if (err) { 1904 kvm_err("Cannot map .hyp.rodata section\n"); 1905 goto out_err; 1906 } 1907 1908 err = create_hyp_mappings(kvm_ksym_ref(__start_rodata), 1909 kvm_ksym_ref(__end_rodata), PAGE_HYP_RO); 1910 if (err) { 1911 kvm_err("Cannot map rodata section\n"); 1912 goto out_err; 1913 } 1914 1915 /* 1916 * .hyp.bss is guaranteed to be placed at the beginning of the .bss 1917 * section thanks to an assertion in the linker script. Map it RW and 1918 * the rest of .bss RO. 1919 */ 1920 err = create_hyp_mappings(kvm_ksym_ref(__hyp_bss_start), 1921 kvm_ksym_ref(__hyp_bss_end), PAGE_HYP); 1922 if (err) { 1923 kvm_err("Cannot map hyp bss section: %d\n", err); 1924 goto out_err; 1925 } 1926 1927 err = create_hyp_mappings(kvm_ksym_ref(__hyp_bss_end), 1928 kvm_ksym_ref(__bss_stop), PAGE_HYP_RO); 1929 if (err) { 1930 kvm_err("Cannot map bss section\n"); 1931 goto out_err; 1932 } 1933 1934 /* 1935 * Map the Hyp stack pages 1936 */ 1937 for_each_possible_cpu(cpu) { 1938 char *stack_page = (char *)per_cpu(kvm_arm_hyp_stack_page, cpu); 1939 err = create_hyp_mappings(stack_page, stack_page + PAGE_SIZE, 1940 PAGE_HYP); 1941 1942 if (err) { 1943 kvm_err("Cannot map hyp stack\n"); 1944 goto out_err; 1945 } 1946 } 1947 1948 for_each_possible_cpu(cpu) { 1949 char *percpu_begin = (char *)kvm_arm_hyp_percpu_base[cpu]; 1950 char *percpu_end = percpu_begin + nvhe_percpu_size(); 1951 1952 /* Map Hyp percpu pages */ 1953 err = create_hyp_mappings(percpu_begin, percpu_end, PAGE_HYP); 1954 if (err) { 1955 kvm_err("Cannot map hyp percpu region\n"); 1956 goto out_err; 1957 } 1958 1959 /* Prepare the CPU initialization parameters */ 1960 cpu_prepare_hyp_mode(cpu); 1961 } 1962 1963 if (is_protected_kvm_enabled()) { 1964 init_cpu_logical_map(); 1965 1966 if (!init_psci_relay()) { 1967 err = -ENODEV; 1968 goto out_err; 1969 } 1970 } 1971 1972 if (is_protected_kvm_enabled()) { 1973 err = kvm_hyp_init_protection(hyp_va_bits); 1974 if (err) { 1975 kvm_err("Failed to init hyp memory protection\n"); 1976 goto out_err; 1977 } 1978 } 1979 1980 return 0; 1981 1982 out_err: 1983 teardown_hyp_mode(); 1984 kvm_err("error initializing Hyp mode: %d\n", err); 1985 return err; 1986 } 1987 1988 static void _kvm_host_prot_finalize(void *arg) 1989 { 1990 int *err = arg; 1991 1992 if (WARN_ON(kvm_call_hyp_nvhe(__pkvm_prot_finalize))) 1993 WRITE_ONCE(*err, -EINVAL); 1994 } 1995 1996 static int pkvm_drop_host_privileges(void) 1997 { 1998 int ret = 0; 1999 2000 /* 2001 * Flip the static key upfront as that may no longer be possible 2002 * once the host stage 2 is installed. 2003 */ 2004 static_branch_enable(&kvm_protected_mode_initialized); 2005 on_each_cpu(_kvm_host_prot_finalize, &ret, 1); 2006 return ret; 2007 } 2008 2009 static int finalize_hyp_mode(void) 2010 { 2011 if (!is_protected_kvm_enabled()) 2012 return 0; 2013 2014 /* 2015 * Exclude HYP BSS from kmemleak so that it doesn't get peeked 2016 * at, which would end badly once the section is inaccessible. 2017 * None of other sections should ever be introspected. 2018 */ 2019 kmemleak_free_part(__hyp_bss_start, __hyp_bss_end - __hyp_bss_start); 2020 return pkvm_drop_host_privileges(); 2021 } 2022 2023 struct kvm_vcpu *kvm_mpidr_to_vcpu(struct kvm *kvm, unsigned long mpidr) 2024 { 2025 struct kvm_vcpu *vcpu; 2026 unsigned long i; 2027 2028 mpidr &= MPIDR_HWID_BITMASK; 2029 kvm_for_each_vcpu(i, vcpu, kvm) { 2030 if (mpidr == kvm_vcpu_get_mpidr_aff(vcpu)) 2031 return vcpu; 2032 } 2033 return NULL; 2034 } 2035 2036 bool kvm_arch_has_irq_bypass(void) 2037 { 2038 return true; 2039 } 2040 2041 int kvm_arch_irq_bypass_add_producer(struct irq_bypass_consumer *cons, 2042 struct irq_bypass_producer *prod) 2043 { 2044 struct kvm_kernel_irqfd *irqfd = 2045 container_of(cons, struct kvm_kernel_irqfd, consumer); 2046 2047 return kvm_vgic_v4_set_forwarding(irqfd->kvm, prod->irq, 2048 &irqfd->irq_entry); 2049 } 2050 void kvm_arch_irq_bypass_del_producer(struct irq_bypass_consumer *cons, 2051 struct irq_bypass_producer *prod) 2052 { 2053 struct kvm_kernel_irqfd *irqfd = 2054 container_of(cons, struct kvm_kernel_irqfd, consumer); 2055 2056 kvm_vgic_v4_unset_forwarding(irqfd->kvm, prod->irq, 2057 &irqfd->irq_entry); 2058 } 2059 2060 void kvm_arch_irq_bypass_stop(struct irq_bypass_consumer *cons) 2061 { 2062 struct kvm_kernel_irqfd *irqfd = 2063 container_of(cons, struct kvm_kernel_irqfd, consumer); 2064 2065 kvm_arm_halt_guest(irqfd->kvm); 2066 } 2067 2068 void kvm_arch_irq_bypass_start(struct irq_bypass_consumer *cons) 2069 { 2070 struct kvm_kernel_irqfd *irqfd = 2071 container_of(cons, struct kvm_kernel_irqfd, consumer); 2072 2073 kvm_arm_resume_guest(irqfd->kvm); 2074 } 2075 2076 /** 2077 * Initialize Hyp-mode and memory mappings on all CPUs. 2078 */ 2079 int kvm_arch_init(void *opaque) 2080 { 2081 int err; 2082 bool in_hyp_mode; 2083 2084 if (!is_hyp_mode_available()) { 2085 kvm_info("HYP mode not available\n"); 2086 return -ENODEV; 2087 } 2088 2089 if (kvm_get_mode() == KVM_MODE_NONE) { 2090 kvm_info("KVM disabled from command line\n"); 2091 return -ENODEV; 2092 } 2093 2094 in_hyp_mode = is_kernel_in_hyp_mode(); 2095 2096 if (cpus_have_final_cap(ARM64_WORKAROUND_DEVICE_LOAD_ACQUIRE) || 2097 cpus_have_final_cap(ARM64_WORKAROUND_1508412)) 2098 kvm_info("Guests without required CPU erratum workarounds can deadlock system!\n" \ 2099 "Only trusted guests should be used on this system.\n"); 2100 2101 err = kvm_set_ipa_limit(); 2102 if (err) 2103 return err; 2104 2105 err = kvm_arm_init_sve(); 2106 if (err) 2107 return err; 2108 2109 err = kvm_arm_vmid_alloc_init(); 2110 if (err) { 2111 kvm_err("Failed to initialize VMID allocator.\n"); 2112 return err; 2113 } 2114 2115 if (!in_hyp_mode) { 2116 err = init_hyp_mode(); 2117 if (err) 2118 goto out_err; 2119 } 2120 2121 err = kvm_init_vector_slots(); 2122 if (err) { 2123 kvm_err("Cannot initialise vector slots\n"); 2124 goto out_err; 2125 } 2126 2127 err = init_subsystems(); 2128 if (err) 2129 goto out_hyp; 2130 2131 if (!in_hyp_mode) { 2132 err = finalize_hyp_mode(); 2133 if (err) { 2134 kvm_err("Failed to finalize Hyp protection\n"); 2135 goto out_hyp; 2136 } 2137 } 2138 2139 if (is_protected_kvm_enabled()) { 2140 kvm_info("Protected nVHE mode initialized successfully\n"); 2141 } else if (in_hyp_mode) { 2142 kvm_info("VHE mode initialized successfully\n"); 2143 } else { 2144 kvm_info("Hyp mode initialized successfully\n"); 2145 } 2146 2147 return 0; 2148 2149 out_hyp: 2150 hyp_cpu_pm_exit(); 2151 if (!in_hyp_mode) 2152 teardown_hyp_mode(); 2153 out_err: 2154 kvm_arm_vmid_alloc_free(); 2155 return err; 2156 } 2157 2158 /* NOP: Compiling as a module not supported */ 2159 void kvm_arch_exit(void) 2160 { 2161 kvm_unregister_perf_callbacks(); 2162 } 2163 2164 static int __init early_kvm_mode_cfg(char *arg) 2165 { 2166 if (!arg) 2167 return -EINVAL; 2168 2169 if (strcmp(arg, "protected") == 0) { 2170 kvm_mode = KVM_MODE_PROTECTED; 2171 return 0; 2172 } 2173 2174 if (strcmp(arg, "nvhe") == 0 && !WARN_ON(is_kernel_in_hyp_mode())) { 2175 kvm_mode = KVM_MODE_DEFAULT; 2176 return 0; 2177 } 2178 2179 if (strcmp(arg, "none") == 0) { 2180 kvm_mode = KVM_MODE_NONE; 2181 return 0; 2182 } 2183 2184 return -EINVAL; 2185 } 2186 early_param("kvm-arm.mode", early_kvm_mode_cfg); 2187 2188 enum kvm_mode kvm_get_mode(void) 2189 { 2190 return kvm_mode; 2191 } 2192 2193 static int arm_init(void) 2194 { 2195 int rc = kvm_init(NULL, sizeof(struct kvm_vcpu), 0, THIS_MODULE); 2196 return rc; 2197 } 2198 2199 module_init(arm_init); 2200