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 kvm_clear_request(KVM_REQ_UNHALT, vcpu); 670 671 preempt_disable(); 672 vgic_v4_load(vcpu); 673 preempt_enable(); 674 } 675 676 static int kvm_vcpu_suspend(struct kvm_vcpu *vcpu) 677 { 678 if (!kvm_arm_vcpu_suspended(vcpu)) 679 return 1; 680 681 kvm_vcpu_wfi(vcpu); 682 683 /* 684 * The suspend state is sticky; we do not leave it until userspace 685 * explicitly marks the vCPU as runnable. Request that we suspend again 686 * later. 687 */ 688 kvm_make_request(KVM_REQ_SUSPEND, vcpu); 689 690 /* 691 * Check to make sure the vCPU is actually runnable. If so, exit to 692 * userspace informing it of the wakeup condition. 693 */ 694 if (kvm_arch_vcpu_runnable(vcpu)) { 695 memset(&vcpu->run->system_event, 0, sizeof(vcpu->run->system_event)); 696 vcpu->run->system_event.type = KVM_SYSTEM_EVENT_WAKEUP; 697 vcpu->run->exit_reason = KVM_EXIT_SYSTEM_EVENT; 698 return 0; 699 } 700 701 /* 702 * Otherwise, we were unblocked to process a different event, such as a 703 * pending signal. Return 1 and allow kvm_arch_vcpu_ioctl_run() to 704 * process the event. 705 */ 706 return 1; 707 } 708 709 /** 710 * check_vcpu_requests - check and handle pending vCPU requests 711 * @vcpu: the VCPU pointer 712 * 713 * Return: 1 if we should enter the guest 714 * 0 if we should exit to userspace 715 * < 0 if we should exit to userspace, where the return value indicates 716 * an error 717 */ 718 static int check_vcpu_requests(struct kvm_vcpu *vcpu) 719 { 720 if (kvm_request_pending(vcpu)) { 721 if (kvm_check_request(KVM_REQ_SLEEP, vcpu)) 722 kvm_vcpu_sleep(vcpu); 723 724 if (kvm_check_request(KVM_REQ_VCPU_RESET, vcpu)) 725 kvm_reset_vcpu(vcpu); 726 727 /* 728 * Clear IRQ_PENDING requests that were made to guarantee 729 * that a VCPU sees new virtual interrupts. 730 */ 731 kvm_check_request(KVM_REQ_IRQ_PENDING, vcpu); 732 733 if (kvm_check_request(KVM_REQ_RECORD_STEAL, vcpu)) 734 kvm_update_stolen_time(vcpu); 735 736 if (kvm_check_request(KVM_REQ_RELOAD_GICv4, vcpu)) { 737 /* The distributor enable bits were changed */ 738 preempt_disable(); 739 vgic_v4_put(vcpu, false); 740 vgic_v4_load(vcpu); 741 preempt_enable(); 742 } 743 744 if (kvm_check_request(KVM_REQ_RELOAD_PMU, vcpu)) 745 kvm_pmu_handle_pmcr(vcpu, 746 __vcpu_sys_reg(vcpu, PMCR_EL0)); 747 748 if (kvm_check_request(KVM_REQ_SUSPEND, vcpu)) 749 return kvm_vcpu_suspend(vcpu); 750 } 751 752 return 1; 753 } 754 755 static bool vcpu_mode_is_bad_32bit(struct kvm_vcpu *vcpu) 756 { 757 if (likely(!vcpu_mode_is_32bit(vcpu))) 758 return false; 759 760 return !system_supports_32bit_el0() || 761 static_branch_unlikely(&arm64_mismatched_32bit_el0); 762 } 763 764 /** 765 * kvm_vcpu_exit_request - returns true if the VCPU should *not* enter the guest 766 * @vcpu: The VCPU pointer 767 * @ret: Pointer to write optional return code 768 * 769 * Returns: true if the VCPU needs to return to a preemptible + interruptible 770 * and skip guest entry. 771 * 772 * This function disambiguates between two different types of exits: exits to a 773 * preemptible + interruptible kernel context and exits to userspace. For an 774 * exit to userspace, this function will write the return code to ret and return 775 * true. For an exit to preemptible + interruptible kernel context (i.e. check 776 * for pending work and re-enter), return true without writing to ret. 777 */ 778 static bool kvm_vcpu_exit_request(struct kvm_vcpu *vcpu, int *ret) 779 { 780 struct kvm_run *run = vcpu->run; 781 782 /* 783 * If we're using a userspace irqchip, then check if we need 784 * to tell a userspace irqchip about timer or PMU level 785 * changes and if so, exit to userspace (the actual level 786 * state gets updated in kvm_timer_update_run and 787 * kvm_pmu_update_run below). 788 */ 789 if (static_branch_unlikely(&userspace_irqchip_in_use)) { 790 if (kvm_timer_should_notify_user(vcpu) || 791 kvm_pmu_should_notify_user(vcpu)) { 792 *ret = -EINTR; 793 run->exit_reason = KVM_EXIT_INTR; 794 return true; 795 } 796 } 797 798 if (unlikely(vcpu_on_unsupported_cpu(vcpu))) { 799 run->exit_reason = KVM_EXIT_FAIL_ENTRY; 800 run->fail_entry.hardware_entry_failure_reason = KVM_EXIT_FAIL_ENTRY_CPU_UNSUPPORTED; 801 run->fail_entry.cpu = smp_processor_id(); 802 *ret = 0; 803 return true; 804 } 805 806 return kvm_request_pending(vcpu) || 807 xfer_to_guest_mode_work_pending(); 808 } 809 810 /* 811 * Actually run the vCPU, entering an RCU extended quiescent state (EQS) while 812 * the vCPU is running. 813 * 814 * This must be noinstr as instrumentation may make use of RCU, and this is not 815 * safe during the EQS. 816 */ 817 static int noinstr kvm_arm_vcpu_enter_exit(struct kvm_vcpu *vcpu) 818 { 819 int ret; 820 821 guest_state_enter_irqoff(); 822 ret = kvm_call_hyp_ret(__kvm_vcpu_run, vcpu); 823 guest_state_exit_irqoff(); 824 825 return ret; 826 } 827 828 /** 829 * kvm_arch_vcpu_ioctl_run - the main VCPU run function to execute guest code 830 * @vcpu: The VCPU pointer 831 * 832 * This function is called through the VCPU_RUN ioctl called from user space. It 833 * will execute VM code in a loop until the time slice for the process is used 834 * or some emulation is needed from user space in which case the function will 835 * return with return value 0 and with the kvm_run structure filled in with the 836 * required data for the requested emulation. 837 */ 838 int kvm_arch_vcpu_ioctl_run(struct kvm_vcpu *vcpu) 839 { 840 struct kvm_run *run = vcpu->run; 841 int ret; 842 843 if (run->exit_reason == KVM_EXIT_MMIO) { 844 ret = kvm_handle_mmio_return(vcpu); 845 if (ret) 846 return ret; 847 } 848 849 vcpu_load(vcpu); 850 851 if (run->immediate_exit) { 852 ret = -EINTR; 853 goto out; 854 } 855 856 kvm_sigset_activate(vcpu); 857 858 ret = 1; 859 run->exit_reason = KVM_EXIT_UNKNOWN; 860 run->flags = 0; 861 while (ret > 0) { 862 /* 863 * Check conditions before entering the guest 864 */ 865 ret = xfer_to_guest_mode_handle_work(vcpu); 866 if (!ret) 867 ret = 1; 868 869 if (ret > 0) 870 ret = check_vcpu_requests(vcpu); 871 872 /* 873 * Preparing the interrupts to be injected also 874 * involves poking the GIC, which must be done in a 875 * non-preemptible context. 876 */ 877 preempt_disable(); 878 879 /* 880 * The VMID allocator only tracks active VMIDs per 881 * physical CPU, and therefore the VMID allocated may not be 882 * preserved on VMID roll-over if the task was preempted, 883 * making a thread's VMID inactive. So we need to call 884 * kvm_arm_vmid_update() in non-premptible context. 885 */ 886 kvm_arm_vmid_update(&vcpu->arch.hw_mmu->vmid); 887 888 kvm_pmu_flush_hwstate(vcpu); 889 890 local_irq_disable(); 891 892 kvm_vgic_flush_hwstate(vcpu); 893 894 kvm_pmu_update_vcpu_events(vcpu); 895 896 /* 897 * Ensure we set mode to IN_GUEST_MODE after we disable 898 * interrupts and before the final VCPU requests check. 899 * See the comment in kvm_vcpu_exiting_guest_mode() and 900 * Documentation/virt/kvm/vcpu-requests.rst 901 */ 902 smp_store_mb(vcpu->mode, IN_GUEST_MODE); 903 904 if (ret <= 0 || kvm_vcpu_exit_request(vcpu, &ret)) { 905 vcpu->mode = OUTSIDE_GUEST_MODE; 906 isb(); /* Ensure work in x_flush_hwstate is committed */ 907 kvm_pmu_sync_hwstate(vcpu); 908 if (static_branch_unlikely(&userspace_irqchip_in_use)) 909 kvm_timer_sync_user(vcpu); 910 kvm_vgic_sync_hwstate(vcpu); 911 local_irq_enable(); 912 preempt_enable(); 913 continue; 914 } 915 916 kvm_arm_setup_debug(vcpu); 917 kvm_arch_vcpu_ctxflush_fp(vcpu); 918 919 /************************************************************** 920 * Enter the guest 921 */ 922 trace_kvm_entry(*vcpu_pc(vcpu)); 923 guest_timing_enter_irqoff(); 924 925 ret = kvm_arm_vcpu_enter_exit(vcpu); 926 927 vcpu->mode = OUTSIDE_GUEST_MODE; 928 vcpu->stat.exits++; 929 /* 930 * Back from guest 931 *************************************************************/ 932 933 kvm_arm_clear_debug(vcpu); 934 935 /* 936 * We must sync the PMU state before the vgic state so 937 * that the vgic can properly sample the updated state of the 938 * interrupt line. 939 */ 940 kvm_pmu_sync_hwstate(vcpu); 941 942 /* 943 * Sync the vgic state before syncing the timer state because 944 * the timer code needs to know if the virtual timer 945 * interrupts are active. 946 */ 947 kvm_vgic_sync_hwstate(vcpu); 948 949 /* 950 * Sync the timer hardware state before enabling interrupts as 951 * we don't want vtimer interrupts to race with syncing the 952 * timer virtual interrupt state. 953 */ 954 if (static_branch_unlikely(&userspace_irqchip_in_use)) 955 kvm_timer_sync_user(vcpu); 956 957 kvm_arch_vcpu_ctxsync_fp(vcpu); 958 959 /* 960 * We must ensure that any pending interrupts are taken before 961 * we exit guest timing so that timer ticks are accounted as 962 * guest time. Transiently unmask interrupts so that any 963 * pending interrupts are taken. 964 * 965 * Per ARM DDI 0487G.b section D1.13.4, an ISB (or other 966 * context synchronization event) is necessary to ensure that 967 * pending interrupts are taken. 968 */ 969 if (ARM_EXCEPTION_CODE(ret) == ARM_EXCEPTION_IRQ) { 970 local_irq_enable(); 971 isb(); 972 local_irq_disable(); 973 } 974 975 guest_timing_exit_irqoff(); 976 977 local_irq_enable(); 978 979 trace_kvm_exit(ret, kvm_vcpu_trap_get_class(vcpu), *vcpu_pc(vcpu)); 980 981 /* Exit types that need handling before we can be preempted */ 982 handle_exit_early(vcpu, ret); 983 984 preempt_enable(); 985 986 /* 987 * The ARMv8 architecture doesn't give the hypervisor 988 * a mechanism to prevent a guest from dropping to AArch32 EL0 989 * if implemented by the CPU. If we spot the guest in such 990 * state and that we decided it wasn't supposed to do so (like 991 * with the asymmetric AArch32 case), return to userspace with 992 * a fatal error. 993 */ 994 if (vcpu_mode_is_bad_32bit(vcpu)) { 995 /* 996 * As we have caught the guest red-handed, decide that 997 * it isn't fit for purpose anymore by making the vcpu 998 * invalid. The VMM can try and fix it by issuing a 999 * KVM_ARM_VCPU_INIT if it really wants to. 1000 */ 1001 vcpu->arch.target = -1; 1002 ret = ARM_EXCEPTION_IL; 1003 } 1004 1005 ret = handle_exit(vcpu, ret); 1006 } 1007 1008 /* Tell userspace about in-kernel device output levels */ 1009 if (unlikely(!irqchip_in_kernel(vcpu->kvm))) { 1010 kvm_timer_update_run(vcpu); 1011 kvm_pmu_update_run(vcpu); 1012 } 1013 1014 kvm_sigset_deactivate(vcpu); 1015 1016 out: 1017 /* 1018 * In the unlikely event that we are returning to userspace 1019 * with pending exceptions or PC adjustment, commit these 1020 * adjustments in order to give userspace a consistent view of 1021 * the vcpu state. Note that this relies on __kvm_adjust_pc() 1022 * being preempt-safe on VHE. 1023 */ 1024 if (unlikely(vcpu_get_flag(vcpu, PENDING_EXCEPTION) || 1025 vcpu_get_flag(vcpu, INCREMENT_PC))) 1026 kvm_call_hyp(__kvm_adjust_pc, vcpu); 1027 1028 vcpu_put(vcpu); 1029 return ret; 1030 } 1031 1032 static int vcpu_interrupt_line(struct kvm_vcpu *vcpu, int number, bool level) 1033 { 1034 int bit_index; 1035 bool set; 1036 unsigned long *hcr; 1037 1038 if (number == KVM_ARM_IRQ_CPU_IRQ) 1039 bit_index = __ffs(HCR_VI); 1040 else /* KVM_ARM_IRQ_CPU_FIQ */ 1041 bit_index = __ffs(HCR_VF); 1042 1043 hcr = vcpu_hcr(vcpu); 1044 if (level) 1045 set = test_and_set_bit(bit_index, hcr); 1046 else 1047 set = test_and_clear_bit(bit_index, hcr); 1048 1049 /* 1050 * If we didn't change anything, no need to wake up or kick other CPUs 1051 */ 1052 if (set == level) 1053 return 0; 1054 1055 /* 1056 * The vcpu irq_lines field was updated, wake up sleeping VCPUs and 1057 * trigger a world-switch round on the running physical CPU to set the 1058 * virtual IRQ/FIQ fields in the HCR appropriately. 1059 */ 1060 kvm_make_request(KVM_REQ_IRQ_PENDING, vcpu); 1061 kvm_vcpu_kick(vcpu); 1062 1063 return 0; 1064 } 1065 1066 int kvm_vm_ioctl_irq_line(struct kvm *kvm, struct kvm_irq_level *irq_level, 1067 bool line_status) 1068 { 1069 u32 irq = irq_level->irq; 1070 unsigned int irq_type, vcpu_idx, irq_num; 1071 int nrcpus = atomic_read(&kvm->online_vcpus); 1072 struct kvm_vcpu *vcpu = NULL; 1073 bool level = irq_level->level; 1074 1075 irq_type = (irq >> KVM_ARM_IRQ_TYPE_SHIFT) & KVM_ARM_IRQ_TYPE_MASK; 1076 vcpu_idx = (irq >> KVM_ARM_IRQ_VCPU_SHIFT) & KVM_ARM_IRQ_VCPU_MASK; 1077 vcpu_idx += ((irq >> KVM_ARM_IRQ_VCPU2_SHIFT) & KVM_ARM_IRQ_VCPU2_MASK) * (KVM_ARM_IRQ_VCPU_MASK + 1); 1078 irq_num = (irq >> KVM_ARM_IRQ_NUM_SHIFT) & KVM_ARM_IRQ_NUM_MASK; 1079 1080 trace_kvm_irq_line(irq_type, vcpu_idx, irq_num, irq_level->level); 1081 1082 switch (irq_type) { 1083 case KVM_ARM_IRQ_TYPE_CPU: 1084 if (irqchip_in_kernel(kvm)) 1085 return -ENXIO; 1086 1087 if (vcpu_idx >= nrcpus) 1088 return -EINVAL; 1089 1090 vcpu = kvm_get_vcpu(kvm, vcpu_idx); 1091 if (!vcpu) 1092 return -EINVAL; 1093 1094 if (irq_num > KVM_ARM_IRQ_CPU_FIQ) 1095 return -EINVAL; 1096 1097 return vcpu_interrupt_line(vcpu, irq_num, level); 1098 case KVM_ARM_IRQ_TYPE_PPI: 1099 if (!irqchip_in_kernel(kvm)) 1100 return -ENXIO; 1101 1102 if (vcpu_idx >= nrcpus) 1103 return -EINVAL; 1104 1105 vcpu = kvm_get_vcpu(kvm, vcpu_idx); 1106 if (!vcpu) 1107 return -EINVAL; 1108 1109 if (irq_num < VGIC_NR_SGIS || irq_num >= VGIC_NR_PRIVATE_IRQS) 1110 return -EINVAL; 1111 1112 return kvm_vgic_inject_irq(kvm, vcpu->vcpu_id, irq_num, level, NULL); 1113 case KVM_ARM_IRQ_TYPE_SPI: 1114 if (!irqchip_in_kernel(kvm)) 1115 return -ENXIO; 1116 1117 if (irq_num < VGIC_NR_PRIVATE_IRQS) 1118 return -EINVAL; 1119 1120 return kvm_vgic_inject_irq(kvm, 0, irq_num, level, NULL); 1121 } 1122 1123 return -EINVAL; 1124 } 1125 1126 static int kvm_vcpu_set_target(struct kvm_vcpu *vcpu, 1127 const struct kvm_vcpu_init *init) 1128 { 1129 unsigned int i, ret; 1130 u32 phys_target = kvm_target_cpu(); 1131 1132 if (init->target != phys_target) 1133 return -EINVAL; 1134 1135 /* 1136 * Secondary and subsequent calls to KVM_ARM_VCPU_INIT must 1137 * use the same target. 1138 */ 1139 if (vcpu->arch.target != -1 && vcpu->arch.target != init->target) 1140 return -EINVAL; 1141 1142 /* -ENOENT for unknown features, -EINVAL for invalid combinations. */ 1143 for (i = 0; i < sizeof(init->features) * 8; i++) { 1144 bool set = (init->features[i / 32] & (1 << (i % 32))); 1145 1146 if (set && i >= KVM_VCPU_MAX_FEATURES) 1147 return -ENOENT; 1148 1149 /* 1150 * Secondary and subsequent calls to KVM_ARM_VCPU_INIT must 1151 * use the same feature set. 1152 */ 1153 if (vcpu->arch.target != -1 && i < KVM_VCPU_MAX_FEATURES && 1154 test_bit(i, vcpu->arch.features) != set) 1155 return -EINVAL; 1156 1157 if (set) 1158 set_bit(i, vcpu->arch.features); 1159 } 1160 1161 vcpu->arch.target = phys_target; 1162 1163 /* Now we know what it is, we can reset it. */ 1164 ret = kvm_reset_vcpu(vcpu); 1165 if (ret) { 1166 vcpu->arch.target = -1; 1167 bitmap_zero(vcpu->arch.features, KVM_VCPU_MAX_FEATURES); 1168 } 1169 1170 return ret; 1171 } 1172 1173 static int kvm_arch_vcpu_ioctl_vcpu_init(struct kvm_vcpu *vcpu, 1174 struct kvm_vcpu_init *init) 1175 { 1176 int ret; 1177 1178 ret = kvm_vcpu_set_target(vcpu, init); 1179 if (ret) 1180 return ret; 1181 1182 /* 1183 * Ensure a rebooted VM will fault in RAM pages and detect if the 1184 * guest MMU is turned off and flush the caches as needed. 1185 * 1186 * S2FWB enforces all memory accesses to RAM being cacheable, 1187 * ensuring that the data side is always coherent. We still 1188 * need to invalidate the I-cache though, as FWB does *not* 1189 * imply CTR_EL0.DIC. 1190 */ 1191 if (vcpu_has_run_once(vcpu)) { 1192 if (!cpus_have_final_cap(ARM64_HAS_STAGE2_FWB)) 1193 stage2_unmap_vm(vcpu->kvm); 1194 else 1195 icache_inval_all_pou(); 1196 } 1197 1198 vcpu_reset_hcr(vcpu); 1199 vcpu->arch.cptr_el2 = CPTR_EL2_DEFAULT; 1200 1201 /* 1202 * Handle the "start in power-off" case. 1203 */ 1204 if (test_bit(KVM_ARM_VCPU_POWER_OFF, vcpu->arch.features)) 1205 kvm_arm_vcpu_power_off(vcpu); 1206 else 1207 vcpu->arch.mp_state.mp_state = KVM_MP_STATE_RUNNABLE; 1208 1209 return 0; 1210 } 1211 1212 static int kvm_arm_vcpu_set_attr(struct kvm_vcpu *vcpu, 1213 struct kvm_device_attr *attr) 1214 { 1215 int ret = -ENXIO; 1216 1217 switch (attr->group) { 1218 default: 1219 ret = kvm_arm_vcpu_arch_set_attr(vcpu, attr); 1220 break; 1221 } 1222 1223 return ret; 1224 } 1225 1226 static int kvm_arm_vcpu_get_attr(struct kvm_vcpu *vcpu, 1227 struct kvm_device_attr *attr) 1228 { 1229 int ret = -ENXIO; 1230 1231 switch (attr->group) { 1232 default: 1233 ret = kvm_arm_vcpu_arch_get_attr(vcpu, attr); 1234 break; 1235 } 1236 1237 return ret; 1238 } 1239 1240 static int kvm_arm_vcpu_has_attr(struct kvm_vcpu *vcpu, 1241 struct kvm_device_attr *attr) 1242 { 1243 int ret = -ENXIO; 1244 1245 switch (attr->group) { 1246 default: 1247 ret = kvm_arm_vcpu_arch_has_attr(vcpu, attr); 1248 break; 1249 } 1250 1251 return ret; 1252 } 1253 1254 static int kvm_arm_vcpu_get_events(struct kvm_vcpu *vcpu, 1255 struct kvm_vcpu_events *events) 1256 { 1257 memset(events, 0, sizeof(*events)); 1258 1259 return __kvm_arm_vcpu_get_events(vcpu, events); 1260 } 1261 1262 static int kvm_arm_vcpu_set_events(struct kvm_vcpu *vcpu, 1263 struct kvm_vcpu_events *events) 1264 { 1265 int i; 1266 1267 /* check whether the reserved field is zero */ 1268 for (i = 0; i < ARRAY_SIZE(events->reserved); i++) 1269 if (events->reserved[i]) 1270 return -EINVAL; 1271 1272 /* check whether the pad field is zero */ 1273 for (i = 0; i < ARRAY_SIZE(events->exception.pad); i++) 1274 if (events->exception.pad[i]) 1275 return -EINVAL; 1276 1277 return __kvm_arm_vcpu_set_events(vcpu, events); 1278 } 1279 1280 long kvm_arch_vcpu_ioctl(struct file *filp, 1281 unsigned int ioctl, unsigned long arg) 1282 { 1283 struct kvm_vcpu *vcpu = filp->private_data; 1284 void __user *argp = (void __user *)arg; 1285 struct kvm_device_attr attr; 1286 long r; 1287 1288 switch (ioctl) { 1289 case KVM_ARM_VCPU_INIT: { 1290 struct kvm_vcpu_init init; 1291 1292 r = -EFAULT; 1293 if (copy_from_user(&init, argp, sizeof(init))) 1294 break; 1295 1296 r = kvm_arch_vcpu_ioctl_vcpu_init(vcpu, &init); 1297 break; 1298 } 1299 case KVM_SET_ONE_REG: 1300 case KVM_GET_ONE_REG: { 1301 struct kvm_one_reg reg; 1302 1303 r = -ENOEXEC; 1304 if (unlikely(!kvm_vcpu_initialized(vcpu))) 1305 break; 1306 1307 r = -EFAULT; 1308 if (copy_from_user(®, argp, sizeof(reg))) 1309 break; 1310 1311 /* 1312 * We could owe a reset due to PSCI. Handle the pending reset 1313 * here to ensure userspace register accesses are ordered after 1314 * the reset. 1315 */ 1316 if (kvm_check_request(KVM_REQ_VCPU_RESET, vcpu)) 1317 kvm_reset_vcpu(vcpu); 1318 1319 if (ioctl == KVM_SET_ONE_REG) 1320 r = kvm_arm_set_reg(vcpu, ®); 1321 else 1322 r = kvm_arm_get_reg(vcpu, ®); 1323 break; 1324 } 1325 case KVM_GET_REG_LIST: { 1326 struct kvm_reg_list __user *user_list = argp; 1327 struct kvm_reg_list reg_list; 1328 unsigned n; 1329 1330 r = -ENOEXEC; 1331 if (unlikely(!kvm_vcpu_initialized(vcpu))) 1332 break; 1333 1334 r = -EPERM; 1335 if (!kvm_arm_vcpu_is_finalized(vcpu)) 1336 break; 1337 1338 r = -EFAULT; 1339 if (copy_from_user(®_list, user_list, sizeof(reg_list))) 1340 break; 1341 n = reg_list.n; 1342 reg_list.n = kvm_arm_num_regs(vcpu); 1343 if (copy_to_user(user_list, ®_list, sizeof(reg_list))) 1344 break; 1345 r = -E2BIG; 1346 if (n < reg_list.n) 1347 break; 1348 r = kvm_arm_copy_reg_indices(vcpu, user_list->reg); 1349 break; 1350 } 1351 case KVM_SET_DEVICE_ATTR: { 1352 r = -EFAULT; 1353 if (copy_from_user(&attr, argp, sizeof(attr))) 1354 break; 1355 r = kvm_arm_vcpu_set_attr(vcpu, &attr); 1356 break; 1357 } 1358 case KVM_GET_DEVICE_ATTR: { 1359 r = -EFAULT; 1360 if (copy_from_user(&attr, argp, sizeof(attr))) 1361 break; 1362 r = kvm_arm_vcpu_get_attr(vcpu, &attr); 1363 break; 1364 } 1365 case KVM_HAS_DEVICE_ATTR: { 1366 r = -EFAULT; 1367 if (copy_from_user(&attr, argp, sizeof(attr))) 1368 break; 1369 r = kvm_arm_vcpu_has_attr(vcpu, &attr); 1370 break; 1371 } 1372 case KVM_GET_VCPU_EVENTS: { 1373 struct kvm_vcpu_events events; 1374 1375 if (kvm_arm_vcpu_get_events(vcpu, &events)) 1376 return -EINVAL; 1377 1378 if (copy_to_user(argp, &events, sizeof(events))) 1379 return -EFAULT; 1380 1381 return 0; 1382 } 1383 case KVM_SET_VCPU_EVENTS: { 1384 struct kvm_vcpu_events events; 1385 1386 if (copy_from_user(&events, argp, sizeof(events))) 1387 return -EFAULT; 1388 1389 return kvm_arm_vcpu_set_events(vcpu, &events); 1390 } 1391 case KVM_ARM_VCPU_FINALIZE: { 1392 int what; 1393 1394 if (!kvm_vcpu_initialized(vcpu)) 1395 return -ENOEXEC; 1396 1397 if (get_user(what, (const int __user *)argp)) 1398 return -EFAULT; 1399 1400 return kvm_arm_vcpu_finalize(vcpu, what); 1401 } 1402 default: 1403 r = -EINVAL; 1404 } 1405 1406 return r; 1407 } 1408 1409 void kvm_arch_sync_dirty_log(struct kvm *kvm, struct kvm_memory_slot *memslot) 1410 { 1411 1412 } 1413 1414 void kvm_arch_flush_remote_tlbs_memslot(struct kvm *kvm, 1415 const struct kvm_memory_slot *memslot) 1416 { 1417 kvm_flush_remote_tlbs(kvm); 1418 } 1419 1420 static int kvm_vm_ioctl_set_device_addr(struct kvm *kvm, 1421 struct kvm_arm_device_addr *dev_addr) 1422 { 1423 switch (FIELD_GET(KVM_ARM_DEVICE_ID_MASK, dev_addr->id)) { 1424 case KVM_ARM_DEVICE_VGIC_V2: 1425 if (!vgic_present) 1426 return -ENXIO; 1427 return kvm_set_legacy_vgic_v2_addr(kvm, dev_addr); 1428 default: 1429 return -ENODEV; 1430 } 1431 } 1432 1433 long kvm_arch_vm_ioctl(struct file *filp, 1434 unsigned int ioctl, unsigned long arg) 1435 { 1436 struct kvm *kvm = filp->private_data; 1437 void __user *argp = (void __user *)arg; 1438 1439 switch (ioctl) { 1440 case KVM_CREATE_IRQCHIP: { 1441 int ret; 1442 if (!vgic_present) 1443 return -ENXIO; 1444 mutex_lock(&kvm->lock); 1445 ret = kvm_vgic_create(kvm, KVM_DEV_TYPE_ARM_VGIC_V2); 1446 mutex_unlock(&kvm->lock); 1447 return ret; 1448 } 1449 case KVM_ARM_SET_DEVICE_ADDR: { 1450 struct kvm_arm_device_addr dev_addr; 1451 1452 if (copy_from_user(&dev_addr, argp, sizeof(dev_addr))) 1453 return -EFAULT; 1454 return kvm_vm_ioctl_set_device_addr(kvm, &dev_addr); 1455 } 1456 case KVM_ARM_PREFERRED_TARGET: { 1457 struct kvm_vcpu_init init; 1458 1459 kvm_vcpu_preferred_target(&init); 1460 1461 if (copy_to_user(argp, &init, sizeof(init))) 1462 return -EFAULT; 1463 1464 return 0; 1465 } 1466 case KVM_ARM_MTE_COPY_TAGS: { 1467 struct kvm_arm_copy_mte_tags copy_tags; 1468 1469 if (copy_from_user(©_tags, argp, sizeof(copy_tags))) 1470 return -EFAULT; 1471 return kvm_vm_ioctl_mte_copy_tags(kvm, ©_tags); 1472 } 1473 default: 1474 return -EINVAL; 1475 } 1476 } 1477 1478 static unsigned long nvhe_percpu_size(void) 1479 { 1480 return (unsigned long)CHOOSE_NVHE_SYM(__per_cpu_end) - 1481 (unsigned long)CHOOSE_NVHE_SYM(__per_cpu_start); 1482 } 1483 1484 static unsigned long nvhe_percpu_order(void) 1485 { 1486 unsigned long size = nvhe_percpu_size(); 1487 1488 return size ? get_order(size) : 0; 1489 } 1490 1491 /* A lookup table holding the hypervisor VA for each vector slot */ 1492 static void *hyp_spectre_vector_selector[BP_HARDEN_EL2_SLOTS]; 1493 1494 static void kvm_init_vector_slot(void *base, enum arm64_hyp_spectre_vector slot) 1495 { 1496 hyp_spectre_vector_selector[slot] = __kvm_vector_slot2addr(base, slot); 1497 } 1498 1499 static int kvm_init_vector_slots(void) 1500 { 1501 int err; 1502 void *base; 1503 1504 base = kern_hyp_va(kvm_ksym_ref(__kvm_hyp_vector)); 1505 kvm_init_vector_slot(base, HYP_VECTOR_DIRECT); 1506 1507 base = kern_hyp_va(kvm_ksym_ref(__bp_harden_hyp_vecs)); 1508 kvm_init_vector_slot(base, HYP_VECTOR_SPECTRE_DIRECT); 1509 1510 if (kvm_system_needs_idmapped_vectors() && 1511 !is_protected_kvm_enabled()) { 1512 err = create_hyp_exec_mappings(__pa_symbol(__bp_harden_hyp_vecs), 1513 __BP_HARDEN_HYP_VECS_SZ, &base); 1514 if (err) 1515 return err; 1516 } 1517 1518 kvm_init_vector_slot(base, HYP_VECTOR_INDIRECT); 1519 kvm_init_vector_slot(base, HYP_VECTOR_SPECTRE_INDIRECT); 1520 return 0; 1521 } 1522 1523 static void cpu_prepare_hyp_mode(int cpu) 1524 { 1525 struct kvm_nvhe_init_params *params = per_cpu_ptr_nvhe_sym(kvm_init_params, cpu); 1526 unsigned long tcr; 1527 1528 /* 1529 * Calculate the raw per-cpu offset without a translation from the 1530 * kernel's mapping to the linear mapping, and store it in tpidr_el2 1531 * so that we can use adr_l to access per-cpu variables in EL2. 1532 * Also drop the KASAN tag which gets in the way... 1533 */ 1534 params->tpidr_el2 = (unsigned long)kasan_reset_tag(per_cpu_ptr_nvhe_sym(__per_cpu_start, cpu)) - 1535 (unsigned long)kvm_ksym_ref(CHOOSE_NVHE_SYM(__per_cpu_start)); 1536 1537 params->mair_el2 = read_sysreg(mair_el1); 1538 1539 /* 1540 * The ID map may be configured to use an extended virtual address 1541 * range. This is only the case if system RAM is out of range for the 1542 * currently configured page size and VA_BITS, in which case we will 1543 * also need the extended virtual range for the HYP ID map, or we won't 1544 * be able to enable the EL2 MMU. 1545 * 1546 * However, at EL2, there is only one TTBR register, and we can't switch 1547 * between translation tables *and* update TCR_EL2.T0SZ at the same 1548 * time. Bottom line: we need to use the extended range with *both* our 1549 * translation tables. 1550 * 1551 * So use the same T0SZ value we use for the ID map. 1552 */ 1553 tcr = (read_sysreg(tcr_el1) & TCR_EL2_MASK) | TCR_EL2_RES1; 1554 tcr &= ~TCR_T0SZ_MASK; 1555 tcr |= (idmap_t0sz & GENMASK(TCR_TxSZ_WIDTH - 1, 0)) << TCR_T0SZ_OFFSET; 1556 params->tcr_el2 = tcr; 1557 1558 params->pgd_pa = kvm_mmu_get_httbr(); 1559 if (is_protected_kvm_enabled()) 1560 params->hcr_el2 = HCR_HOST_NVHE_PROTECTED_FLAGS; 1561 else 1562 params->hcr_el2 = HCR_HOST_NVHE_FLAGS; 1563 params->vttbr = params->vtcr = 0; 1564 1565 /* 1566 * Flush the init params from the data cache because the struct will 1567 * be read while the MMU is off. 1568 */ 1569 kvm_flush_dcache_to_poc(params, sizeof(*params)); 1570 } 1571 1572 static void hyp_install_host_vector(void) 1573 { 1574 struct kvm_nvhe_init_params *params; 1575 struct arm_smccc_res res; 1576 1577 /* Switch from the HYP stub to our own HYP init vector */ 1578 __hyp_set_vectors(kvm_get_idmap_vector()); 1579 1580 /* 1581 * Call initialization code, and switch to the full blown HYP code. 1582 * If the cpucaps haven't been finalized yet, something has gone very 1583 * wrong, and hyp will crash and burn when it uses any 1584 * cpus_have_const_cap() wrapper. 1585 */ 1586 BUG_ON(!system_capabilities_finalized()); 1587 params = this_cpu_ptr_nvhe_sym(kvm_init_params); 1588 arm_smccc_1_1_hvc(KVM_HOST_SMCCC_FUNC(__kvm_hyp_init), virt_to_phys(params), &res); 1589 WARN_ON(res.a0 != SMCCC_RET_SUCCESS); 1590 } 1591 1592 static void cpu_init_hyp_mode(void) 1593 { 1594 hyp_install_host_vector(); 1595 1596 /* 1597 * Disabling SSBD on a non-VHE system requires us to enable SSBS 1598 * at EL2. 1599 */ 1600 if (this_cpu_has_cap(ARM64_SSBS) && 1601 arm64_get_spectre_v4_state() == SPECTRE_VULNERABLE) { 1602 kvm_call_hyp_nvhe(__kvm_enable_ssbs); 1603 } 1604 } 1605 1606 static void cpu_hyp_reset(void) 1607 { 1608 if (!is_kernel_in_hyp_mode()) 1609 __hyp_reset_vectors(); 1610 } 1611 1612 /* 1613 * EL2 vectors can be mapped and rerouted in a number of ways, 1614 * depending on the kernel configuration and CPU present: 1615 * 1616 * - If the CPU is affected by Spectre-v2, the hardening sequence is 1617 * placed in one of the vector slots, which is executed before jumping 1618 * to the real vectors. 1619 * 1620 * - If the CPU also has the ARM64_SPECTRE_V3A cap, the slot 1621 * containing the hardening sequence is mapped next to the idmap page, 1622 * and executed before jumping to the real vectors. 1623 * 1624 * - If the CPU only has the ARM64_SPECTRE_V3A cap, then an 1625 * empty slot is selected, mapped next to the idmap page, and 1626 * executed before jumping to the real vectors. 1627 * 1628 * Note that ARM64_SPECTRE_V3A is somewhat incompatible with 1629 * VHE, as we don't have hypervisor-specific mappings. If the system 1630 * is VHE and yet selects this capability, it will be ignored. 1631 */ 1632 static void cpu_set_hyp_vector(void) 1633 { 1634 struct bp_hardening_data *data = this_cpu_ptr(&bp_hardening_data); 1635 void *vector = hyp_spectre_vector_selector[data->slot]; 1636 1637 if (!is_protected_kvm_enabled()) 1638 *this_cpu_ptr_hyp_sym(kvm_hyp_vector) = (unsigned long)vector; 1639 else 1640 kvm_call_hyp_nvhe(__pkvm_cpu_set_vector, data->slot); 1641 } 1642 1643 static void cpu_hyp_init_context(void) 1644 { 1645 kvm_init_host_cpu_context(&this_cpu_ptr_hyp_sym(kvm_host_data)->host_ctxt); 1646 1647 if (!is_kernel_in_hyp_mode()) 1648 cpu_init_hyp_mode(); 1649 } 1650 1651 static void cpu_hyp_init_features(void) 1652 { 1653 cpu_set_hyp_vector(); 1654 kvm_arm_init_debug(); 1655 1656 if (is_kernel_in_hyp_mode()) 1657 kvm_timer_init_vhe(); 1658 1659 if (vgic_present) 1660 kvm_vgic_init_cpu_hardware(); 1661 } 1662 1663 static void cpu_hyp_reinit(void) 1664 { 1665 cpu_hyp_reset(); 1666 cpu_hyp_init_context(); 1667 cpu_hyp_init_features(); 1668 } 1669 1670 static void _kvm_arch_hardware_enable(void *discard) 1671 { 1672 if (!__this_cpu_read(kvm_arm_hardware_enabled)) { 1673 cpu_hyp_reinit(); 1674 __this_cpu_write(kvm_arm_hardware_enabled, 1); 1675 } 1676 } 1677 1678 int kvm_arch_hardware_enable(void) 1679 { 1680 _kvm_arch_hardware_enable(NULL); 1681 return 0; 1682 } 1683 1684 static void _kvm_arch_hardware_disable(void *discard) 1685 { 1686 if (__this_cpu_read(kvm_arm_hardware_enabled)) { 1687 cpu_hyp_reset(); 1688 __this_cpu_write(kvm_arm_hardware_enabled, 0); 1689 } 1690 } 1691 1692 void kvm_arch_hardware_disable(void) 1693 { 1694 if (!is_protected_kvm_enabled()) 1695 _kvm_arch_hardware_disable(NULL); 1696 } 1697 1698 #ifdef CONFIG_CPU_PM 1699 static int hyp_init_cpu_pm_notifier(struct notifier_block *self, 1700 unsigned long cmd, 1701 void *v) 1702 { 1703 /* 1704 * kvm_arm_hardware_enabled is left with its old value over 1705 * PM_ENTER->PM_EXIT. It is used to indicate PM_EXIT should 1706 * re-enable hyp. 1707 */ 1708 switch (cmd) { 1709 case CPU_PM_ENTER: 1710 if (__this_cpu_read(kvm_arm_hardware_enabled)) 1711 /* 1712 * don't update kvm_arm_hardware_enabled here 1713 * so that the hardware will be re-enabled 1714 * when we resume. See below. 1715 */ 1716 cpu_hyp_reset(); 1717 1718 return NOTIFY_OK; 1719 case CPU_PM_ENTER_FAILED: 1720 case CPU_PM_EXIT: 1721 if (__this_cpu_read(kvm_arm_hardware_enabled)) 1722 /* The hardware was enabled before suspend. */ 1723 cpu_hyp_reinit(); 1724 1725 return NOTIFY_OK; 1726 1727 default: 1728 return NOTIFY_DONE; 1729 } 1730 } 1731 1732 static struct notifier_block hyp_init_cpu_pm_nb = { 1733 .notifier_call = hyp_init_cpu_pm_notifier, 1734 }; 1735 1736 static void hyp_cpu_pm_init(void) 1737 { 1738 if (!is_protected_kvm_enabled()) 1739 cpu_pm_register_notifier(&hyp_init_cpu_pm_nb); 1740 } 1741 static void hyp_cpu_pm_exit(void) 1742 { 1743 if (!is_protected_kvm_enabled()) 1744 cpu_pm_unregister_notifier(&hyp_init_cpu_pm_nb); 1745 } 1746 #else 1747 static inline void hyp_cpu_pm_init(void) 1748 { 1749 } 1750 static inline void hyp_cpu_pm_exit(void) 1751 { 1752 } 1753 #endif 1754 1755 static void init_cpu_logical_map(void) 1756 { 1757 unsigned int cpu; 1758 1759 /* 1760 * Copy the MPIDR <-> logical CPU ID mapping to hyp. 1761 * Only copy the set of online CPUs whose features have been checked 1762 * against the finalized system capabilities. The hypervisor will not 1763 * allow any other CPUs from the `possible` set to boot. 1764 */ 1765 for_each_online_cpu(cpu) 1766 hyp_cpu_logical_map[cpu] = cpu_logical_map(cpu); 1767 } 1768 1769 #define init_psci_0_1_impl_state(config, what) \ 1770 config.psci_0_1_ ## what ## _implemented = psci_ops.what 1771 1772 static bool init_psci_relay(void) 1773 { 1774 /* 1775 * If PSCI has not been initialized, protected KVM cannot install 1776 * itself on newly booted CPUs. 1777 */ 1778 if (!psci_ops.get_version) { 1779 kvm_err("Cannot initialize protected mode without PSCI\n"); 1780 return false; 1781 } 1782 1783 kvm_host_psci_config.version = psci_ops.get_version(); 1784 1785 if (kvm_host_psci_config.version == PSCI_VERSION(0, 1)) { 1786 kvm_host_psci_config.function_ids_0_1 = get_psci_0_1_function_ids(); 1787 init_psci_0_1_impl_state(kvm_host_psci_config, cpu_suspend); 1788 init_psci_0_1_impl_state(kvm_host_psci_config, cpu_on); 1789 init_psci_0_1_impl_state(kvm_host_psci_config, cpu_off); 1790 init_psci_0_1_impl_state(kvm_host_psci_config, migrate); 1791 } 1792 return true; 1793 } 1794 1795 static int init_subsystems(void) 1796 { 1797 int err = 0; 1798 1799 /* 1800 * Enable hardware so that subsystem initialisation can access EL2. 1801 */ 1802 on_each_cpu(_kvm_arch_hardware_enable, NULL, 1); 1803 1804 /* 1805 * Register CPU lower-power notifier 1806 */ 1807 hyp_cpu_pm_init(); 1808 1809 /* 1810 * Init HYP view of VGIC 1811 */ 1812 err = kvm_vgic_hyp_init(); 1813 switch (err) { 1814 case 0: 1815 vgic_present = true; 1816 break; 1817 case -ENODEV: 1818 case -ENXIO: 1819 vgic_present = false; 1820 err = 0; 1821 break; 1822 default: 1823 goto out; 1824 } 1825 1826 /* 1827 * Init HYP architected timer support 1828 */ 1829 err = kvm_timer_hyp_init(vgic_present); 1830 if (err) 1831 goto out; 1832 1833 kvm_register_perf_callbacks(NULL); 1834 1835 out: 1836 if (err || !is_protected_kvm_enabled()) 1837 on_each_cpu(_kvm_arch_hardware_disable, NULL, 1); 1838 1839 return err; 1840 } 1841 1842 static void teardown_hyp_mode(void) 1843 { 1844 int cpu; 1845 1846 free_hyp_pgds(); 1847 for_each_possible_cpu(cpu) { 1848 free_page(per_cpu(kvm_arm_hyp_stack_page, cpu)); 1849 free_pages(kvm_arm_hyp_percpu_base[cpu], nvhe_percpu_order()); 1850 } 1851 } 1852 1853 static int do_pkvm_init(u32 hyp_va_bits) 1854 { 1855 void *per_cpu_base = kvm_ksym_ref(kvm_arm_hyp_percpu_base); 1856 int ret; 1857 1858 preempt_disable(); 1859 cpu_hyp_init_context(); 1860 ret = kvm_call_hyp_nvhe(__pkvm_init, hyp_mem_base, hyp_mem_size, 1861 num_possible_cpus(), kern_hyp_va(per_cpu_base), 1862 hyp_va_bits); 1863 cpu_hyp_init_features(); 1864 1865 /* 1866 * The stub hypercalls are now disabled, so set our local flag to 1867 * prevent a later re-init attempt in kvm_arch_hardware_enable(). 1868 */ 1869 __this_cpu_write(kvm_arm_hardware_enabled, 1); 1870 preempt_enable(); 1871 1872 return ret; 1873 } 1874 1875 static int kvm_hyp_init_protection(u32 hyp_va_bits) 1876 { 1877 void *addr = phys_to_virt(hyp_mem_base); 1878 int ret; 1879 1880 kvm_nvhe_sym(id_aa64pfr0_el1_sys_val) = read_sanitised_ftr_reg(SYS_ID_AA64PFR0_EL1); 1881 kvm_nvhe_sym(id_aa64pfr1_el1_sys_val) = read_sanitised_ftr_reg(SYS_ID_AA64PFR1_EL1); 1882 kvm_nvhe_sym(id_aa64isar0_el1_sys_val) = read_sanitised_ftr_reg(SYS_ID_AA64ISAR0_EL1); 1883 kvm_nvhe_sym(id_aa64isar1_el1_sys_val) = read_sanitised_ftr_reg(SYS_ID_AA64ISAR1_EL1); 1884 kvm_nvhe_sym(id_aa64isar2_el1_sys_val) = read_sanitised_ftr_reg(SYS_ID_AA64ISAR2_EL1); 1885 kvm_nvhe_sym(id_aa64mmfr0_el1_sys_val) = read_sanitised_ftr_reg(SYS_ID_AA64MMFR0_EL1); 1886 kvm_nvhe_sym(id_aa64mmfr1_el1_sys_val) = read_sanitised_ftr_reg(SYS_ID_AA64MMFR1_EL1); 1887 kvm_nvhe_sym(id_aa64mmfr2_el1_sys_val) = read_sanitised_ftr_reg(SYS_ID_AA64MMFR2_EL1); 1888 1889 ret = create_hyp_mappings(addr, addr + hyp_mem_size, PAGE_HYP); 1890 if (ret) 1891 return ret; 1892 1893 ret = do_pkvm_init(hyp_va_bits); 1894 if (ret) 1895 return ret; 1896 1897 free_hyp_pgds(); 1898 1899 return 0; 1900 } 1901 1902 /** 1903 * Inits Hyp-mode on all online CPUs 1904 */ 1905 static int init_hyp_mode(void) 1906 { 1907 u32 hyp_va_bits; 1908 int cpu; 1909 int err = -ENOMEM; 1910 1911 /* 1912 * The protected Hyp-mode cannot be initialized if the memory pool 1913 * allocation has failed. 1914 */ 1915 if (is_protected_kvm_enabled() && !hyp_mem_base) 1916 goto out_err; 1917 1918 /* 1919 * Allocate Hyp PGD and setup Hyp identity mapping 1920 */ 1921 err = kvm_mmu_init(&hyp_va_bits); 1922 if (err) 1923 goto out_err; 1924 1925 /* 1926 * Allocate stack pages for Hypervisor-mode 1927 */ 1928 for_each_possible_cpu(cpu) { 1929 unsigned long stack_page; 1930 1931 stack_page = __get_free_page(GFP_KERNEL); 1932 if (!stack_page) { 1933 err = -ENOMEM; 1934 goto out_err; 1935 } 1936 1937 per_cpu(kvm_arm_hyp_stack_page, cpu) = stack_page; 1938 } 1939 1940 /* 1941 * Allocate and initialize pages for Hypervisor-mode percpu regions. 1942 */ 1943 for_each_possible_cpu(cpu) { 1944 struct page *page; 1945 void *page_addr; 1946 1947 page = alloc_pages(GFP_KERNEL, nvhe_percpu_order()); 1948 if (!page) { 1949 err = -ENOMEM; 1950 goto out_err; 1951 } 1952 1953 page_addr = page_address(page); 1954 memcpy(page_addr, CHOOSE_NVHE_SYM(__per_cpu_start), nvhe_percpu_size()); 1955 kvm_arm_hyp_percpu_base[cpu] = (unsigned long)page_addr; 1956 } 1957 1958 /* 1959 * Map the Hyp-code called directly from the host 1960 */ 1961 err = create_hyp_mappings(kvm_ksym_ref(__hyp_text_start), 1962 kvm_ksym_ref(__hyp_text_end), PAGE_HYP_EXEC); 1963 if (err) { 1964 kvm_err("Cannot map world-switch code\n"); 1965 goto out_err; 1966 } 1967 1968 err = create_hyp_mappings(kvm_ksym_ref(__hyp_rodata_start), 1969 kvm_ksym_ref(__hyp_rodata_end), PAGE_HYP_RO); 1970 if (err) { 1971 kvm_err("Cannot map .hyp.rodata section\n"); 1972 goto out_err; 1973 } 1974 1975 err = create_hyp_mappings(kvm_ksym_ref(__start_rodata), 1976 kvm_ksym_ref(__end_rodata), PAGE_HYP_RO); 1977 if (err) { 1978 kvm_err("Cannot map rodata section\n"); 1979 goto out_err; 1980 } 1981 1982 /* 1983 * .hyp.bss is guaranteed to be placed at the beginning of the .bss 1984 * section thanks to an assertion in the linker script. Map it RW and 1985 * the rest of .bss RO. 1986 */ 1987 err = create_hyp_mappings(kvm_ksym_ref(__hyp_bss_start), 1988 kvm_ksym_ref(__hyp_bss_end), PAGE_HYP); 1989 if (err) { 1990 kvm_err("Cannot map hyp bss section: %d\n", err); 1991 goto out_err; 1992 } 1993 1994 err = create_hyp_mappings(kvm_ksym_ref(__hyp_bss_end), 1995 kvm_ksym_ref(__bss_stop), PAGE_HYP_RO); 1996 if (err) { 1997 kvm_err("Cannot map bss section\n"); 1998 goto out_err; 1999 } 2000 2001 /* 2002 * Map the Hyp stack pages 2003 */ 2004 for_each_possible_cpu(cpu) { 2005 struct kvm_nvhe_init_params *params = per_cpu_ptr_nvhe_sym(kvm_init_params, cpu); 2006 char *stack_page = (char *)per_cpu(kvm_arm_hyp_stack_page, cpu); 2007 unsigned long hyp_addr; 2008 2009 /* 2010 * Allocate a contiguous HYP private VA range for the stack 2011 * and guard page. The allocation is also aligned based on 2012 * the order of its size. 2013 */ 2014 err = hyp_alloc_private_va_range(PAGE_SIZE * 2, &hyp_addr); 2015 if (err) { 2016 kvm_err("Cannot allocate hyp stack guard page\n"); 2017 goto out_err; 2018 } 2019 2020 /* 2021 * Since the stack grows downwards, map the stack to the page 2022 * at the higher address and leave the lower guard page 2023 * unbacked. 2024 * 2025 * Any valid stack address now has the PAGE_SHIFT bit as 1 2026 * and addresses corresponding to the guard page have the 2027 * PAGE_SHIFT bit as 0 - this is used for overflow detection. 2028 */ 2029 err = __create_hyp_mappings(hyp_addr + PAGE_SIZE, PAGE_SIZE, 2030 __pa(stack_page), PAGE_HYP); 2031 if (err) { 2032 kvm_err("Cannot map hyp stack\n"); 2033 goto out_err; 2034 } 2035 2036 /* 2037 * Save the stack PA in nvhe_init_params. This will be needed 2038 * to recreate the stack mapping in protected nVHE mode. 2039 * __hyp_pa() won't do the right thing there, since the stack 2040 * has been mapped in the flexible private VA space. 2041 */ 2042 params->stack_pa = __pa(stack_page); 2043 2044 params->stack_hyp_va = hyp_addr + (2 * PAGE_SIZE); 2045 } 2046 2047 for_each_possible_cpu(cpu) { 2048 char *percpu_begin = (char *)kvm_arm_hyp_percpu_base[cpu]; 2049 char *percpu_end = percpu_begin + nvhe_percpu_size(); 2050 2051 /* Map Hyp percpu pages */ 2052 err = create_hyp_mappings(percpu_begin, percpu_end, PAGE_HYP); 2053 if (err) { 2054 kvm_err("Cannot map hyp percpu region\n"); 2055 goto out_err; 2056 } 2057 2058 /* Prepare the CPU initialization parameters */ 2059 cpu_prepare_hyp_mode(cpu); 2060 } 2061 2062 if (is_protected_kvm_enabled()) { 2063 init_cpu_logical_map(); 2064 2065 if (!init_psci_relay()) { 2066 err = -ENODEV; 2067 goto out_err; 2068 } 2069 } 2070 2071 if (is_protected_kvm_enabled()) { 2072 err = kvm_hyp_init_protection(hyp_va_bits); 2073 if (err) { 2074 kvm_err("Failed to init hyp memory protection\n"); 2075 goto out_err; 2076 } 2077 } 2078 2079 return 0; 2080 2081 out_err: 2082 teardown_hyp_mode(); 2083 kvm_err("error initializing Hyp mode: %d\n", err); 2084 return err; 2085 } 2086 2087 static void _kvm_host_prot_finalize(void *arg) 2088 { 2089 int *err = arg; 2090 2091 if (WARN_ON(kvm_call_hyp_nvhe(__pkvm_prot_finalize))) 2092 WRITE_ONCE(*err, -EINVAL); 2093 } 2094 2095 static int pkvm_drop_host_privileges(void) 2096 { 2097 int ret = 0; 2098 2099 /* 2100 * Flip the static key upfront as that may no longer be possible 2101 * once the host stage 2 is installed. 2102 */ 2103 static_branch_enable(&kvm_protected_mode_initialized); 2104 on_each_cpu(_kvm_host_prot_finalize, &ret, 1); 2105 return ret; 2106 } 2107 2108 static int finalize_hyp_mode(void) 2109 { 2110 if (!is_protected_kvm_enabled()) 2111 return 0; 2112 2113 /* 2114 * Exclude HYP sections from kmemleak so that they don't get peeked 2115 * at, which would end badly once inaccessible. 2116 */ 2117 kmemleak_free_part(__hyp_bss_start, __hyp_bss_end - __hyp_bss_start); 2118 kmemleak_free_part(__va(hyp_mem_base), hyp_mem_size); 2119 return pkvm_drop_host_privileges(); 2120 } 2121 2122 struct kvm_vcpu *kvm_mpidr_to_vcpu(struct kvm *kvm, unsigned long mpidr) 2123 { 2124 struct kvm_vcpu *vcpu; 2125 unsigned long i; 2126 2127 mpidr &= MPIDR_HWID_BITMASK; 2128 kvm_for_each_vcpu(i, vcpu, kvm) { 2129 if (mpidr == kvm_vcpu_get_mpidr_aff(vcpu)) 2130 return vcpu; 2131 } 2132 return NULL; 2133 } 2134 2135 bool kvm_arch_has_irq_bypass(void) 2136 { 2137 return true; 2138 } 2139 2140 int kvm_arch_irq_bypass_add_producer(struct irq_bypass_consumer *cons, 2141 struct irq_bypass_producer *prod) 2142 { 2143 struct kvm_kernel_irqfd *irqfd = 2144 container_of(cons, struct kvm_kernel_irqfd, consumer); 2145 2146 return kvm_vgic_v4_set_forwarding(irqfd->kvm, prod->irq, 2147 &irqfd->irq_entry); 2148 } 2149 void kvm_arch_irq_bypass_del_producer(struct irq_bypass_consumer *cons, 2150 struct irq_bypass_producer *prod) 2151 { 2152 struct kvm_kernel_irqfd *irqfd = 2153 container_of(cons, struct kvm_kernel_irqfd, consumer); 2154 2155 kvm_vgic_v4_unset_forwarding(irqfd->kvm, prod->irq, 2156 &irqfd->irq_entry); 2157 } 2158 2159 void kvm_arch_irq_bypass_stop(struct irq_bypass_consumer *cons) 2160 { 2161 struct kvm_kernel_irqfd *irqfd = 2162 container_of(cons, struct kvm_kernel_irqfd, consumer); 2163 2164 kvm_arm_halt_guest(irqfd->kvm); 2165 } 2166 2167 void kvm_arch_irq_bypass_start(struct irq_bypass_consumer *cons) 2168 { 2169 struct kvm_kernel_irqfd *irqfd = 2170 container_of(cons, struct kvm_kernel_irqfd, consumer); 2171 2172 kvm_arm_resume_guest(irqfd->kvm); 2173 } 2174 2175 /** 2176 * Initialize Hyp-mode and memory mappings on all CPUs. 2177 */ 2178 int kvm_arch_init(void *opaque) 2179 { 2180 int err; 2181 bool in_hyp_mode; 2182 2183 if (!is_hyp_mode_available()) { 2184 kvm_info("HYP mode not available\n"); 2185 return -ENODEV; 2186 } 2187 2188 if (kvm_get_mode() == KVM_MODE_NONE) { 2189 kvm_info("KVM disabled from command line\n"); 2190 return -ENODEV; 2191 } 2192 2193 err = kvm_sys_reg_table_init(); 2194 if (err) { 2195 kvm_info("Error initializing system register tables"); 2196 return err; 2197 } 2198 2199 in_hyp_mode = is_kernel_in_hyp_mode(); 2200 2201 if (cpus_have_final_cap(ARM64_WORKAROUND_DEVICE_LOAD_ACQUIRE) || 2202 cpus_have_final_cap(ARM64_WORKAROUND_1508412)) 2203 kvm_info("Guests without required CPU erratum workarounds can deadlock system!\n" \ 2204 "Only trusted guests should be used on this system.\n"); 2205 2206 err = kvm_set_ipa_limit(); 2207 if (err) 2208 return err; 2209 2210 err = kvm_arm_init_sve(); 2211 if (err) 2212 return err; 2213 2214 err = kvm_arm_vmid_alloc_init(); 2215 if (err) { 2216 kvm_err("Failed to initialize VMID allocator.\n"); 2217 return err; 2218 } 2219 2220 if (!in_hyp_mode) { 2221 err = init_hyp_mode(); 2222 if (err) 2223 goto out_err; 2224 } 2225 2226 err = kvm_init_vector_slots(); 2227 if (err) { 2228 kvm_err("Cannot initialise vector slots\n"); 2229 goto out_err; 2230 } 2231 2232 err = init_subsystems(); 2233 if (err) 2234 goto out_hyp; 2235 2236 if (!in_hyp_mode) { 2237 err = finalize_hyp_mode(); 2238 if (err) { 2239 kvm_err("Failed to finalize Hyp protection\n"); 2240 goto out_hyp; 2241 } 2242 } 2243 2244 if (is_protected_kvm_enabled()) { 2245 kvm_info("Protected nVHE mode initialized successfully\n"); 2246 } else if (in_hyp_mode) { 2247 kvm_info("VHE mode initialized successfully\n"); 2248 } else { 2249 kvm_info("Hyp mode initialized successfully\n"); 2250 } 2251 2252 return 0; 2253 2254 out_hyp: 2255 hyp_cpu_pm_exit(); 2256 if (!in_hyp_mode) 2257 teardown_hyp_mode(); 2258 out_err: 2259 kvm_arm_vmid_alloc_free(); 2260 return err; 2261 } 2262 2263 /* NOP: Compiling as a module not supported */ 2264 void kvm_arch_exit(void) 2265 { 2266 kvm_unregister_perf_callbacks(); 2267 } 2268 2269 static int __init early_kvm_mode_cfg(char *arg) 2270 { 2271 if (!arg) 2272 return -EINVAL; 2273 2274 if (strcmp(arg, "protected") == 0) { 2275 if (!is_kernel_in_hyp_mode()) 2276 kvm_mode = KVM_MODE_PROTECTED; 2277 else 2278 pr_warn_once("Protected KVM not available with VHE\n"); 2279 2280 return 0; 2281 } 2282 2283 if (strcmp(arg, "nvhe") == 0 && !WARN_ON(is_kernel_in_hyp_mode())) { 2284 kvm_mode = KVM_MODE_DEFAULT; 2285 return 0; 2286 } 2287 2288 if (strcmp(arg, "none") == 0) { 2289 kvm_mode = KVM_MODE_NONE; 2290 return 0; 2291 } 2292 2293 return -EINVAL; 2294 } 2295 early_param("kvm-arm.mode", early_kvm_mode_cfg); 2296 2297 enum kvm_mode kvm_get_mode(void) 2298 { 2299 return kvm_mode; 2300 } 2301 2302 static int arm_init(void) 2303 { 2304 int rc = kvm_init(NULL, sizeof(struct kvm_vcpu), 0, THIS_MODULE); 2305 return rc; 2306 } 2307 2308 module_init(arm_init); 2309