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/errno.h> 10 #include <linux/err.h> 11 #include <linux/kvm_host.h> 12 #include <linux/list.h> 13 #include <linux/module.h> 14 #include <linux/vmalloc.h> 15 #include <linux/fs.h> 16 #include <linux/mman.h> 17 #include <linux/sched.h> 18 #include <linux/kvm.h> 19 #include <linux/kvm_irqfd.h> 20 #include <linux/irqbypass.h> 21 #include <linux/sched/stat.h> 22 #include <trace/events/kvm.h> 23 24 #define CREATE_TRACE_POINTS 25 #include "trace_arm.h" 26 27 #include <linux/uaccess.h> 28 #include <asm/ptrace.h> 29 #include <asm/mman.h> 30 #include <asm/tlbflush.h> 31 #include <asm/cacheflush.h> 32 #include <asm/cpufeature.h> 33 #include <asm/virt.h> 34 #include <asm/kvm_arm.h> 35 #include <asm/kvm_asm.h> 36 #include <asm/kvm_mmu.h> 37 #include <asm/kvm_emulate.h> 38 #include <asm/kvm_coproc.h> 39 #include <asm/sections.h> 40 41 #include <kvm/arm_hypercalls.h> 42 #include <kvm/arm_pmu.h> 43 #include <kvm/arm_psci.h> 44 45 #ifdef REQUIRES_VIRT 46 __asm__(".arch_extension virt"); 47 #endif 48 49 DECLARE_KVM_HYP_PER_CPU(unsigned long, kvm_hyp_vector); 50 51 static DEFINE_PER_CPU(unsigned long, kvm_arm_hyp_stack_page); 52 unsigned long kvm_arm_hyp_percpu_base[NR_CPUS]; 53 54 /* The VMID used in the VTTBR */ 55 static atomic64_t kvm_vmid_gen = ATOMIC64_INIT(1); 56 static u32 kvm_next_vmid; 57 static DEFINE_SPINLOCK(kvm_vmid_lock); 58 59 static bool vgic_present; 60 61 static DEFINE_PER_CPU(unsigned char, kvm_arm_hardware_enabled); 62 DEFINE_STATIC_KEY_FALSE(userspace_irqchip_in_use); 63 64 int kvm_arch_vcpu_should_kick(struct kvm_vcpu *vcpu) 65 { 66 return kvm_vcpu_exiting_guest_mode(vcpu) == IN_GUEST_MODE; 67 } 68 69 int kvm_arch_hardware_setup(void *opaque) 70 { 71 return 0; 72 } 73 74 int kvm_arch_check_processor_compat(void *opaque) 75 { 76 return 0; 77 } 78 79 int kvm_vm_ioctl_enable_cap(struct kvm *kvm, 80 struct kvm_enable_cap *cap) 81 { 82 int r; 83 84 if (cap->flags) 85 return -EINVAL; 86 87 switch (cap->cap) { 88 case KVM_CAP_ARM_NISV_TO_USER: 89 r = 0; 90 kvm->arch.return_nisv_io_abort_to_user = true; 91 break; 92 default: 93 r = -EINVAL; 94 break; 95 } 96 97 return r; 98 } 99 100 static int kvm_arm_default_max_vcpus(void) 101 { 102 return vgic_present ? kvm_vgic_get_max_vcpus() : KVM_MAX_VCPUS; 103 } 104 105 static void set_default_csv2(struct kvm *kvm) 106 { 107 /* 108 * The default is to expose CSV2 == 1 if the HW isn't affected. 109 * Although this is a per-CPU feature, we make it global because 110 * asymmetric systems are just a nuisance. 111 * 112 * Userspace can override this as long as it doesn't promise 113 * the impossible. 114 */ 115 if (arm64_get_spectre_v2_state() == SPECTRE_UNAFFECTED) 116 kvm->arch.pfr0_csv2 = 1; 117 } 118 119 /** 120 * kvm_arch_init_vm - initializes a VM data structure 121 * @kvm: pointer to the KVM struct 122 */ 123 int kvm_arch_init_vm(struct kvm *kvm, unsigned long type) 124 { 125 int ret; 126 127 ret = kvm_arm_setup_stage2(kvm, type); 128 if (ret) 129 return ret; 130 131 ret = kvm_init_stage2_mmu(kvm, &kvm->arch.mmu); 132 if (ret) 133 return ret; 134 135 ret = create_hyp_mappings(kvm, kvm + 1, PAGE_HYP); 136 if (ret) 137 goto out_free_stage2_pgd; 138 139 kvm_vgic_early_init(kvm); 140 141 /* The maximum number of VCPUs is limited by the host's GIC model */ 142 kvm->arch.max_vcpus = kvm_arm_default_max_vcpus(); 143 144 set_default_csv2(kvm); 145 146 return ret; 147 out_free_stage2_pgd: 148 kvm_free_stage2_pgd(&kvm->arch.mmu); 149 return ret; 150 } 151 152 vm_fault_t kvm_arch_vcpu_fault(struct kvm_vcpu *vcpu, struct vm_fault *vmf) 153 { 154 return VM_FAULT_SIGBUS; 155 } 156 157 158 /** 159 * kvm_arch_destroy_vm - destroy the VM data structure 160 * @kvm: pointer to the KVM struct 161 */ 162 void kvm_arch_destroy_vm(struct kvm *kvm) 163 { 164 int i; 165 166 bitmap_free(kvm->arch.pmu_filter); 167 168 kvm_vgic_destroy(kvm); 169 170 for (i = 0; i < KVM_MAX_VCPUS; ++i) { 171 if (kvm->vcpus[i]) { 172 kvm_vcpu_destroy(kvm->vcpus[i]); 173 kvm->vcpus[i] = NULL; 174 } 175 } 176 atomic_set(&kvm->online_vcpus, 0); 177 } 178 179 int kvm_vm_ioctl_check_extension(struct kvm *kvm, long ext) 180 { 181 int r; 182 switch (ext) { 183 case KVM_CAP_IRQCHIP: 184 r = vgic_present; 185 break; 186 case KVM_CAP_IOEVENTFD: 187 case KVM_CAP_DEVICE_CTRL: 188 case KVM_CAP_USER_MEMORY: 189 case KVM_CAP_SYNC_MMU: 190 case KVM_CAP_DESTROY_MEMORY_REGION_WORKS: 191 case KVM_CAP_ONE_REG: 192 case KVM_CAP_ARM_PSCI: 193 case KVM_CAP_ARM_PSCI_0_2: 194 case KVM_CAP_READONLY_MEM: 195 case KVM_CAP_MP_STATE: 196 case KVM_CAP_IMMEDIATE_EXIT: 197 case KVM_CAP_VCPU_EVENTS: 198 case KVM_CAP_ARM_IRQ_LINE_LAYOUT_2: 199 case KVM_CAP_ARM_NISV_TO_USER: 200 case KVM_CAP_ARM_INJECT_EXT_DABT: 201 r = 1; 202 break; 203 case KVM_CAP_ARM_SET_DEVICE_ADDR: 204 r = 1; 205 break; 206 case KVM_CAP_NR_VCPUS: 207 r = num_online_cpus(); 208 break; 209 case KVM_CAP_MAX_VCPUS: 210 case KVM_CAP_MAX_VCPU_ID: 211 if (kvm) 212 r = kvm->arch.max_vcpus; 213 else 214 r = kvm_arm_default_max_vcpus(); 215 break; 216 case KVM_CAP_MSI_DEVID: 217 if (!kvm) 218 r = -EINVAL; 219 else 220 r = kvm->arch.vgic.msis_require_devid; 221 break; 222 case KVM_CAP_ARM_USER_IRQ: 223 /* 224 * 1: EL1_VTIMER, EL1_PTIMER, and PMU. 225 * (bump this number if adding more devices) 226 */ 227 r = 1; 228 break; 229 case KVM_CAP_STEAL_TIME: 230 r = kvm_arm_pvtime_supported(); 231 break; 232 default: 233 r = kvm_arch_vm_ioctl_check_extension(kvm, ext); 234 break; 235 } 236 return r; 237 } 238 239 long kvm_arch_dev_ioctl(struct file *filp, 240 unsigned int ioctl, unsigned long arg) 241 { 242 return -EINVAL; 243 } 244 245 struct kvm *kvm_arch_alloc_vm(void) 246 { 247 if (!has_vhe()) 248 return kzalloc(sizeof(struct kvm), GFP_KERNEL); 249 250 return vzalloc(sizeof(struct kvm)); 251 } 252 253 void kvm_arch_free_vm(struct kvm *kvm) 254 { 255 if (!has_vhe()) 256 kfree(kvm); 257 else 258 vfree(kvm); 259 } 260 261 int kvm_arch_vcpu_precreate(struct kvm *kvm, unsigned int id) 262 { 263 if (irqchip_in_kernel(kvm) && vgic_initialized(kvm)) 264 return -EBUSY; 265 266 if (id >= kvm->arch.max_vcpus) 267 return -EINVAL; 268 269 return 0; 270 } 271 272 int kvm_arch_vcpu_create(struct kvm_vcpu *vcpu) 273 { 274 int err; 275 276 /* Force users to call KVM_ARM_VCPU_INIT */ 277 vcpu->arch.target = -1; 278 bitmap_zero(vcpu->arch.features, KVM_VCPU_MAX_FEATURES); 279 280 vcpu->arch.mmu_page_cache.gfp_zero = __GFP_ZERO; 281 282 /* Set up the timer */ 283 kvm_timer_vcpu_init(vcpu); 284 285 kvm_pmu_vcpu_init(vcpu); 286 287 kvm_arm_reset_debug_ptr(vcpu); 288 289 kvm_arm_pvtime_vcpu_init(&vcpu->arch); 290 291 vcpu->arch.hw_mmu = &vcpu->kvm->arch.mmu; 292 293 err = kvm_vgic_vcpu_init(vcpu); 294 if (err) 295 return err; 296 297 return create_hyp_mappings(vcpu, vcpu + 1, PAGE_HYP); 298 } 299 300 void kvm_arch_vcpu_postcreate(struct kvm_vcpu *vcpu) 301 { 302 } 303 304 void kvm_arch_vcpu_destroy(struct kvm_vcpu *vcpu) 305 { 306 if (vcpu->arch.has_run_once && unlikely(!irqchip_in_kernel(vcpu->kvm))) 307 static_branch_dec(&userspace_irqchip_in_use); 308 309 kvm_mmu_free_memory_cache(&vcpu->arch.mmu_page_cache); 310 kvm_timer_vcpu_terminate(vcpu); 311 kvm_pmu_vcpu_destroy(vcpu); 312 313 kvm_arm_vcpu_destroy(vcpu); 314 } 315 316 int kvm_cpu_has_pending_timer(struct kvm_vcpu *vcpu) 317 { 318 return kvm_timer_is_pending(vcpu); 319 } 320 321 void kvm_arch_vcpu_blocking(struct kvm_vcpu *vcpu) 322 { 323 /* 324 * If we're about to block (most likely because we've just hit a 325 * WFI), we need to sync back the state of the GIC CPU interface 326 * so that we have the latest PMR and group enables. This ensures 327 * that kvm_arch_vcpu_runnable has up-to-date data to decide 328 * whether we have pending interrupts. 329 * 330 * For the same reason, we want to tell GICv4 that we need 331 * doorbells to be signalled, should an interrupt become pending. 332 */ 333 preempt_disable(); 334 kvm_vgic_vmcr_sync(vcpu); 335 vgic_v4_put(vcpu, true); 336 preempt_enable(); 337 } 338 339 void kvm_arch_vcpu_unblocking(struct kvm_vcpu *vcpu) 340 { 341 preempt_disable(); 342 vgic_v4_load(vcpu); 343 preempt_enable(); 344 } 345 346 void kvm_arch_vcpu_load(struct kvm_vcpu *vcpu, int cpu) 347 { 348 struct kvm_s2_mmu *mmu; 349 int *last_ran; 350 351 mmu = vcpu->arch.hw_mmu; 352 last_ran = this_cpu_ptr(mmu->last_vcpu_ran); 353 354 /* 355 * We might get preempted before the vCPU actually runs, but 356 * over-invalidation doesn't affect correctness. 357 */ 358 if (*last_ran != vcpu->vcpu_id) { 359 kvm_call_hyp(__kvm_tlb_flush_local_vmid, mmu); 360 *last_ran = vcpu->vcpu_id; 361 } 362 363 vcpu->cpu = cpu; 364 365 kvm_vgic_load(vcpu); 366 kvm_timer_vcpu_load(vcpu); 367 if (has_vhe()) 368 kvm_vcpu_load_sysregs_vhe(vcpu); 369 kvm_arch_vcpu_load_fp(vcpu); 370 kvm_vcpu_pmu_restore_guest(vcpu); 371 if (kvm_arm_is_pvtime_enabled(&vcpu->arch)) 372 kvm_make_request(KVM_REQ_RECORD_STEAL, vcpu); 373 374 if (single_task_running()) 375 vcpu_clear_wfx_traps(vcpu); 376 else 377 vcpu_set_wfx_traps(vcpu); 378 379 if (vcpu_has_ptrauth(vcpu)) 380 vcpu_ptrauth_disable(vcpu); 381 } 382 383 void kvm_arch_vcpu_put(struct kvm_vcpu *vcpu) 384 { 385 kvm_arch_vcpu_put_fp(vcpu); 386 if (has_vhe()) 387 kvm_vcpu_put_sysregs_vhe(vcpu); 388 kvm_timer_vcpu_put(vcpu); 389 kvm_vgic_put(vcpu); 390 kvm_vcpu_pmu_restore_host(vcpu); 391 392 vcpu->cpu = -1; 393 } 394 395 static void vcpu_power_off(struct kvm_vcpu *vcpu) 396 { 397 vcpu->arch.power_off = true; 398 kvm_make_request(KVM_REQ_SLEEP, vcpu); 399 kvm_vcpu_kick(vcpu); 400 } 401 402 int kvm_arch_vcpu_ioctl_get_mpstate(struct kvm_vcpu *vcpu, 403 struct kvm_mp_state *mp_state) 404 { 405 if (vcpu->arch.power_off) 406 mp_state->mp_state = KVM_MP_STATE_STOPPED; 407 else 408 mp_state->mp_state = KVM_MP_STATE_RUNNABLE; 409 410 return 0; 411 } 412 413 int kvm_arch_vcpu_ioctl_set_mpstate(struct kvm_vcpu *vcpu, 414 struct kvm_mp_state *mp_state) 415 { 416 int ret = 0; 417 418 switch (mp_state->mp_state) { 419 case KVM_MP_STATE_RUNNABLE: 420 vcpu->arch.power_off = false; 421 break; 422 case KVM_MP_STATE_STOPPED: 423 vcpu_power_off(vcpu); 424 break; 425 default: 426 ret = -EINVAL; 427 } 428 429 return ret; 430 } 431 432 /** 433 * kvm_arch_vcpu_runnable - determine if the vcpu can be scheduled 434 * @v: The VCPU pointer 435 * 436 * If the guest CPU is not waiting for interrupts or an interrupt line is 437 * asserted, the CPU is by definition runnable. 438 */ 439 int kvm_arch_vcpu_runnable(struct kvm_vcpu *v) 440 { 441 bool irq_lines = *vcpu_hcr(v) & (HCR_VI | HCR_VF); 442 return ((irq_lines || kvm_vgic_vcpu_pending_irq(v)) 443 && !v->arch.power_off && !v->arch.pause); 444 } 445 446 bool kvm_arch_vcpu_in_kernel(struct kvm_vcpu *vcpu) 447 { 448 return vcpu_mode_priv(vcpu); 449 } 450 451 /* Just ensure a guest exit from a particular CPU */ 452 static void exit_vm_noop(void *info) 453 { 454 } 455 456 void force_vm_exit(const cpumask_t *mask) 457 { 458 preempt_disable(); 459 smp_call_function_many(mask, exit_vm_noop, NULL, true); 460 preempt_enable(); 461 } 462 463 /** 464 * need_new_vmid_gen - check that the VMID is still valid 465 * @vmid: The VMID to check 466 * 467 * return true if there is a new generation of VMIDs being used 468 * 469 * The hardware supports a limited set of values with the value zero reserved 470 * for the host, so we check if an assigned value belongs to a previous 471 * generation, which requires us to assign a new value. If we're the first to 472 * use a VMID for the new generation, we must flush necessary caches and TLBs 473 * on all CPUs. 474 */ 475 static bool need_new_vmid_gen(struct kvm_vmid *vmid) 476 { 477 u64 current_vmid_gen = atomic64_read(&kvm_vmid_gen); 478 smp_rmb(); /* Orders read of kvm_vmid_gen and kvm->arch.vmid */ 479 return unlikely(READ_ONCE(vmid->vmid_gen) != current_vmid_gen); 480 } 481 482 /** 483 * update_vmid - Update the vmid with a valid VMID for the current generation 484 * @vmid: The stage-2 VMID information struct 485 */ 486 static void update_vmid(struct kvm_vmid *vmid) 487 { 488 if (!need_new_vmid_gen(vmid)) 489 return; 490 491 spin_lock(&kvm_vmid_lock); 492 493 /* 494 * We need to re-check the vmid_gen here to ensure that if another vcpu 495 * already allocated a valid vmid for this vm, then this vcpu should 496 * use the same vmid. 497 */ 498 if (!need_new_vmid_gen(vmid)) { 499 spin_unlock(&kvm_vmid_lock); 500 return; 501 } 502 503 /* First user of a new VMID generation? */ 504 if (unlikely(kvm_next_vmid == 0)) { 505 atomic64_inc(&kvm_vmid_gen); 506 kvm_next_vmid = 1; 507 508 /* 509 * On SMP we know no other CPUs can use this CPU's or each 510 * other's VMID after force_vm_exit returns since the 511 * kvm_vmid_lock blocks them from reentry to the guest. 512 */ 513 force_vm_exit(cpu_all_mask); 514 /* 515 * Now broadcast TLB + ICACHE invalidation over the inner 516 * shareable domain to make sure all data structures are 517 * clean. 518 */ 519 kvm_call_hyp(__kvm_flush_vm_context); 520 } 521 522 vmid->vmid = kvm_next_vmid; 523 kvm_next_vmid++; 524 kvm_next_vmid &= (1 << kvm_get_vmid_bits()) - 1; 525 526 smp_wmb(); 527 WRITE_ONCE(vmid->vmid_gen, atomic64_read(&kvm_vmid_gen)); 528 529 spin_unlock(&kvm_vmid_lock); 530 } 531 532 static int kvm_vcpu_first_run_init(struct kvm_vcpu *vcpu) 533 { 534 struct kvm *kvm = vcpu->kvm; 535 int ret = 0; 536 537 if (likely(vcpu->arch.has_run_once)) 538 return 0; 539 540 if (!kvm_arm_vcpu_is_finalized(vcpu)) 541 return -EPERM; 542 543 vcpu->arch.has_run_once = true; 544 545 if (likely(irqchip_in_kernel(kvm))) { 546 /* 547 * Map the VGIC hardware resources before running a vcpu the 548 * first time on this VM. 549 */ 550 if (unlikely(!vgic_ready(kvm))) { 551 ret = kvm_vgic_map_resources(kvm); 552 if (ret) 553 return ret; 554 } 555 } else { 556 /* 557 * Tell the rest of the code that there are userspace irqchip 558 * VMs in the wild. 559 */ 560 static_branch_inc(&userspace_irqchip_in_use); 561 } 562 563 ret = kvm_timer_enable(vcpu); 564 if (ret) 565 return ret; 566 567 ret = kvm_arm_pmu_v3_enable(vcpu); 568 569 return ret; 570 } 571 572 bool kvm_arch_intc_initialized(struct kvm *kvm) 573 { 574 return vgic_initialized(kvm); 575 } 576 577 void kvm_arm_halt_guest(struct kvm *kvm) 578 { 579 int i; 580 struct kvm_vcpu *vcpu; 581 582 kvm_for_each_vcpu(i, vcpu, kvm) 583 vcpu->arch.pause = true; 584 kvm_make_all_cpus_request(kvm, KVM_REQ_SLEEP); 585 } 586 587 void kvm_arm_resume_guest(struct kvm *kvm) 588 { 589 int i; 590 struct kvm_vcpu *vcpu; 591 592 kvm_for_each_vcpu(i, vcpu, kvm) { 593 vcpu->arch.pause = false; 594 rcuwait_wake_up(kvm_arch_vcpu_get_wait(vcpu)); 595 } 596 } 597 598 static void vcpu_req_sleep(struct kvm_vcpu *vcpu) 599 { 600 struct rcuwait *wait = kvm_arch_vcpu_get_wait(vcpu); 601 602 rcuwait_wait_event(wait, 603 (!vcpu->arch.power_off) &&(!vcpu->arch.pause), 604 TASK_INTERRUPTIBLE); 605 606 if (vcpu->arch.power_off || vcpu->arch.pause) { 607 /* Awaken to handle a signal, request we sleep again later. */ 608 kvm_make_request(KVM_REQ_SLEEP, vcpu); 609 } 610 611 /* 612 * Make sure we will observe a potential reset request if we've 613 * observed a change to the power state. Pairs with the smp_wmb() in 614 * kvm_psci_vcpu_on(). 615 */ 616 smp_rmb(); 617 } 618 619 static int kvm_vcpu_initialized(struct kvm_vcpu *vcpu) 620 { 621 return vcpu->arch.target >= 0; 622 } 623 624 static void check_vcpu_requests(struct kvm_vcpu *vcpu) 625 { 626 if (kvm_request_pending(vcpu)) { 627 if (kvm_check_request(KVM_REQ_SLEEP, vcpu)) 628 vcpu_req_sleep(vcpu); 629 630 if (kvm_check_request(KVM_REQ_VCPU_RESET, vcpu)) 631 kvm_reset_vcpu(vcpu); 632 633 /* 634 * Clear IRQ_PENDING requests that were made to guarantee 635 * that a VCPU sees new virtual interrupts. 636 */ 637 kvm_check_request(KVM_REQ_IRQ_PENDING, vcpu); 638 639 if (kvm_check_request(KVM_REQ_RECORD_STEAL, vcpu)) 640 kvm_update_stolen_time(vcpu); 641 642 if (kvm_check_request(KVM_REQ_RELOAD_GICv4, vcpu)) { 643 /* The distributor enable bits were changed */ 644 preempt_disable(); 645 vgic_v4_put(vcpu, false); 646 vgic_v4_load(vcpu); 647 preempt_enable(); 648 } 649 } 650 } 651 652 /** 653 * kvm_arch_vcpu_ioctl_run - the main VCPU run function to execute guest code 654 * @vcpu: The VCPU pointer 655 * 656 * This function is called through the VCPU_RUN ioctl called from user space. It 657 * will execute VM code in a loop until the time slice for the process is used 658 * or some emulation is needed from user space in which case the function will 659 * return with return value 0 and with the kvm_run structure filled in with the 660 * required data for the requested emulation. 661 */ 662 int kvm_arch_vcpu_ioctl_run(struct kvm_vcpu *vcpu) 663 { 664 struct kvm_run *run = vcpu->run; 665 int ret; 666 667 if (unlikely(!kvm_vcpu_initialized(vcpu))) 668 return -ENOEXEC; 669 670 ret = kvm_vcpu_first_run_init(vcpu); 671 if (ret) 672 return ret; 673 674 if (run->exit_reason == KVM_EXIT_MMIO) { 675 ret = kvm_handle_mmio_return(vcpu); 676 if (ret) 677 return ret; 678 } 679 680 if (run->immediate_exit) 681 return -EINTR; 682 683 vcpu_load(vcpu); 684 685 kvm_sigset_activate(vcpu); 686 687 ret = 1; 688 run->exit_reason = KVM_EXIT_UNKNOWN; 689 while (ret > 0) { 690 /* 691 * Check conditions before entering the guest 692 */ 693 cond_resched(); 694 695 update_vmid(&vcpu->arch.hw_mmu->vmid); 696 697 check_vcpu_requests(vcpu); 698 699 /* 700 * Preparing the interrupts to be injected also 701 * involves poking the GIC, which must be done in a 702 * non-preemptible context. 703 */ 704 preempt_disable(); 705 706 kvm_pmu_flush_hwstate(vcpu); 707 708 local_irq_disable(); 709 710 kvm_vgic_flush_hwstate(vcpu); 711 712 /* 713 * Exit if we have a signal pending so that we can deliver the 714 * signal to user space. 715 */ 716 if (signal_pending(current)) { 717 ret = -EINTR; 718 run->exit_reason = KVM_EXIT_INTR; 719 } 720 721 /* 722 * If we're using a userspace irqchip, then check if we need 723 * to tell a userspace irqchip about timer or PMU level 724 * changes and if so, exit to userspace (the actual level 725 * state gets updated in kvm_timer_update_run and 726 * kvm_pmu_update_run below). 727 */ 728 if (static_branch_unlikely(&userspace_irqchip_in_use)) { 729 if (kvm_timer_should_notify_user(vcpu) || 730 kvm_pmu_should_notify_user(vcpu)) { 731 ret = -EINTR; 732 run->exit_reason = KVM_EXIT_INTR; 733 } 734 } 735 736 /* 737 * Ensure we set mode to IN_GUEST_MODE after we disable 738 * interrupts and before the final VCPU requests check. 739 * See the comment in kvm_vcpu_exiting_guest_mode() and 740 * Documentation/virt/kvm/vcpu-requests.rst 741 */ 742 smp_store_mb(vcpu->mode, IN_GUEST_MODE); 743 744 if (ret <= 0 || need_new_vmid_gen(&vcpu->arch.hw_mmu->vmid) || 745 kvm_request_pending(vcpu)) { 746 vcpu->mode = OUTSIDE_GUEST_MODE; 747 isb(); /* Ensure work in x_flush_hwstate is committed */ 748 kvm_pmu_sync_hwstate(vcpu); 749 if (static_branch_unlikely(&userspace_irqchip_in_use)) 750 kvm_timer_sync_user(vcpu); 751 kvm_vgic_sync_hwstate(vcpu); 752 local_irq_enable(); 753 preempt_enable(); 754 continue; 755 } 756 757 kvm_arm_setup_debug(vcpu); 758 759 /************************************************************** 760 * Enter the guest 761 */ 762 trace_kvm_entry(*vcpu_pc(vcpu)); 763 guest_enter_irqoff(); 764 765 ret = kvm_call_hyp_ret(__kvm_vcpu_run, vcpu); 766 767 vcpu->mode = OUTSIDE_GUEST_MODE; 768 vcpu->stat.exits++; 769 /* 770 * Back from guest 771 *************************************************************/ 772 773 kvm_arm_clear_debug(vcpu); 774 775 /* 776 * We must sync the PMU state before the vgic state so 777 * that the vgic can properly sample the updated state of the 778 * interrupt line. 779 */ 780 kvm_pmu_sync_hwstate(vcpu); 781 782 /* 783 * Sync the vgic state before syncing the timer state because 784 * the timer code needs to know if the virtual timer 785 * interrupts are active. 786 */ 787 kvm_vgic_sync_hwstate(vcpu); 788 789 /* 790 * Sync the timer hardware state before enabling interrupts as 791 * we don't want vtimer interrupts to race with syncing the 792 * timer virtual interrupt state. 793 */ 794 if (static_branch_unlikely(&userspace_irqchip_in_use)) 795 kvm_timer_sync_user(vcpu); 796 797 kvm_arch_vcpu_ctxsync_fp(vcpu); 798 799 /* 800 * We may have taken a host interrupt in HYP mode (ie 801 * while executing the guest). This interrupt is still 802 * pending, as we haven't serviced it yet! 803 * 804 * We're now back in SVC mode, with interrupts 805 * disabled. Enabling the interrupts now will have 806 * the effect of taking the interrupt again, in SVC 807 * mode this time. 808 */ 809 local_irq_enable(); 810 811 /* 812 * We do local_irq_enable() before calling guest_exit() so 813 * that if a timer interrupt hits while running the guest we 814 * account that tick as being spent in the guest. We enable 815 * preemption after calling guest_exit() so that if we get 816 * preempted we make sure ticks after that is not counted as 817 * guest time. 818 */ 819 guest_exit(); 820 trace_kvm_exit(ret, kvm_vcpu_trap_get_class(vcpu), *vcpu_pc(vcpu)); 821 822 /* Exit types that need handling before we can be preempted */ 823 handle_exit_early(vcpu, ret); 824 825 preempt_enable(); 826 827 /* 828 * The ARMv8 architecture doesn't give the hypervisor 829 * a mechanism to prevent a guest from dropping to AArch32 EL0 830 * if implemented by the CPU. If we spot the guest in such 831 * state and that we decided it wasn't supposed to do so (like 832 * with the asymmetric AArch32 case), return to userspace with 833 * a fatal error. 834 */ 835 if (!system_supports_32bit_el0() && vcpu_mode_is_32bit(vcpu)) { 836 /* 837 * As we have caught the guest red-handed, decide that 838 * it isn't fit for purpose anymore by making the vcpu 839 * invalid. The VMM can try and fix it by issuing a 840 * KVM_ARM_VCPU_INIT if it really wants to. 841 */ 842 vcpu->arch.target = -1; 843 ret = ARM_EXCEPTION_IL; 844 } 845 846 ret = handle_exit(vcpu, ret); 847 } 848 849 /* Tell userspace about in-kernel device output levels */ 850 if (unlikely(!irqchip_in_kernel(vcpu->kvm))) { 851 kvm_timer_update_run(vcpu); 852 kvm_pmu_update_run(vcpu); 853 } 854 855 kvm_sigset_deactivate(vcpu); 856 857 vcpu_put(vcpu); 858 return ret; 859 } 860 861 static int vcpu_interrupt_line(struct kvm_vcpu *vcpu, int number, bool level) 862 { 863 int bit_index; 864 bool set; 865 unsigned long *hcr; 866 867 if (number == KVM_ARM_IRQ_CPU_IRQ) 868 bit_index = __ffs(HCR_VI); 869 else /* KVM_ARM_IRQ_CPU_FIQ */ 870 bit_index = __ffs(HCR_VF); 871 872 hcr = vcpu_hcr(vcpu); 873 if (level) 874 set = test_and_set_bit(bit_index, hcr); 875 else 876 set = test_and_clear_bit(bit_index, hcr); 877 878 /* 879 * If we didn't change anything, no need to wake up or kick other CPUs 880 */ 881 if (set == level) 882 return 0; 883 884 /* 885 * The vcpu irq_lines field was updated, wake up sleeping VCPUs and 886 * trigger a world-switch round on the running physical CPU to set the 887 * virtual IRQ/FIQ fields in the HCR appropriately. 888 */ 889 kvm_make_request(KVM_REQ_IRQ_PENDING, vcpu); 890 kvm_vcpu_kick(vcpu); 891 892 return 0; 893 } 894 895 int kvm_vm_ioctl_irq_line(struct kvm *kvm, struct kvm_irq_level *irq_level, 896 bool line_status) 897 { 898 u32 irq = irq_level->irq; 899 unsigned int irq_type, vcpu_idx, irq_num; 900 int nrcpus = atomic_read(&kvm->online_vcpus); 901 struct kvm_vcpu *vcpu = NULL; 902 bool level = irq_level->level; 903 904 irq_type = (irq >> KVM_ARM_IRQ_TYPE_SHIFT) & KVM_ARM_IRQ_TYPE_MASK; 905 vcpu_idx = (irq >> KVM_ARM_IRQ_VCPU_SHIFT) & KVM_ARM_IRQ_VCPU_MASK; 906 vcpu_idx += ((irq >> KVM_ARM_IRQ_VCPU2_SHIFT) & KVM_ARM_IRQ_VCPU2_MASK) * (KVM_ARM_IRQ_VCPU_MASK + 1); 907 irq_num = (irq >> KVM_ARM_IRQ_NUM_SHIFT) & KVM_ARM_IRQ_NUM_MASK; 908 909 trace_kvm_irq_line(irq_type, vcpu_idx, irq_num, irq_level->level); 910 911 switch (irq_type) { 912 case KVM_ARM_IRQ_TYPE_CPU: 913 if (irqchip_in_kernel(kvm)) 914 return -ENXIO; 915 916 if (vcpu_idx >= nrcpus) 917 return -EINVAL; 918 919 vcpu = kvm_get_vcpu(kvm, vcpu_idx); 920 if (!vcpu) 921 return -EINVAL; 922 923 if (irq_num > KVM_ARM_IRQ_CPU_FIQ) 924 return -EINVAL; 925 926 return vcpu_interrupt_line(vcpu, irq_num, level); 927 case KVM_ARM_IRQ_TYPE_PPI: 928 if (!irqchip_in_kernel(kvm)) 929 return -ENXIO; 930 931 if (vcpu_idx >= nrcpus) 932 return -EINVAL; 933 934 vcpu = kvm_get_vcpu(kvm, vcpu_idx); 935 if (!vcpu) 936 return -EINVAL; 937 938 if (irq_num < VGIC_NR_SGIS || irq_num >= VGIC_NR_PRIVATE_IRQS) 939 return -EINVAL; 940 941 return kvm_vgic_inject_irq(kvm, vcpu->vcpu_id, irq_num, level, NULL); 942 case KVM_ARM_IRQ_TYPE_SPI: 943 if (!irqchip_in_kernel(kvm)) 944 return -ENXIO; 945 946 if (irq_num < VGIC_NR_PRIVATE_IRQS) 947 return -EINVAL; 948 949 return kvm_vgic_inject_irq(kvm, 0, irq_num, level, NULL); 950 } 951 952 return -EINVAL; 953 } 954 955 static int kvm_vcpu_set_target(struct kvm_vcpu *vcpu, 956 const struct kvm_vcpu_init *init) 957 { 958 unsigned int i, ret; 959 int phys_target = kvm_target_cpu(); 960 961 if (init->target != phys_target) 962 return -EINVAL; 963 964 /* 965 * Secondary and subsequent calls to KVM_ARM_VCPU_INIT must 966 * use the same target. 967 */ 968 if (vcpu->arch.target != -1 && vcpu->arch.target != init->target) 969 return -EINVAL; 970 971 /* -ENOENT for unknown features, -EINVAL for invalid combinations. */ 972 for (i = 0; i < sizeof(init->features) * 8; i++) { 973 bool set = (init->features[i / 32] & (1 << (i % 32))); 974 975 if (set && i >= KVM_VCPU_MAX_FEATURES) 976 return -ENOENT; 977 978 /* 979 * Secondary and subsequent calls to KVM_ARM_VCPU_INIT must 980 * use the same feature set. 981 */ 982 if (vcpu->arch.target != -1 && i < KVM_VCPU_MAX_FEATURES && 983 test_bit(i, vcpu->arch.features) != set) 984 return -EINVAL; 985 986 if (set) 987 set_bit(i, vcpu->arch.features); 988 } 989 990 vcpu->arch.target = phys_target; 991 992 /* Now we know what it is, we can reset it. */ 993 ret = kvm_reset_vcpu(vcpu); 994 if (ret) { 995 vcpu->arch.target = -1; 996 bitmap_zero(vcpu->arch.features, KVM_VCPU_MAX_FEATURES); 997 } 998 999 return ret; 1000 } 1001 1002 static int kvm_arch_vcpu_ioctl_vcpu_init(struct kvm_vcpu *vcpu, 1003 struct kvm_vcpu_init *init) 1004 { 1005 int ret; 1006 1007 ret = kvm_vcpu_set_target(vcpu, init); 1008 if (ret) 1009 return ret; 1010 1011 /* 1012 * Ensure a rebooted VM will fault in RAM pages and detect if the 1013 * guest MMU is turned off and flush the caches as needed. 1014 * 1015 * S2FWB enforces all memory accesses to RAM being cacheable, 1016 * ensuring that the data side is always coherent. We still 1017 * need to invalidate the I-cache though, as FWB does *not* 1018 * imply CTR_EL0.DIC. 1019 */ 1020 if (vcpu->arch.has_run_once) { 1021 if (!cpus_have_final_cap(ARM64_HAS_STAGE2_FWB)) 1022 stage2_unmap_vm(vcpu->kvm); 1023 else 1024 __flush_icache_all(); 1025 } 1026 1027 vcpu_reset_hcr(vcpu); 1028 1029 /* 1030 * Handle the "start in power-off" case. 1031 */ 1032 if (test_bit(KVM_ARM_VCPU_POWER_OFF, vcpu->arch.features)) 1033 vcpu_power_off(vcpu); 1034 else 1035 vcpu->arch.power_off = false; 1036 1037 return 0; 1038 } 1039 1040 static int kvm_arm_vcpu_set_attr(struct kvm_vcpu *vcpu, 1041 struct kvm_device_attr *attr) 1042 { 1043 int ret = -ENXIO; 1044 1045 switch (attr->group) { 1046 default: 1047 ret = kvm_arm_vcpu_arch_set_attr(vcpu, attr); 1048 break; 1049 } 1050 1051 return ret; 1052 } 1053 1054 static int kvm_arm_vcpu_get_attr(struct kvm_vcpu *vcpu, 1055 struct kvm_device_attr *attr) 1056 { 1057 int ret = -ENXIO; 1058 1059 switch (attr->group) { 1060 default: 1061 ret = kvm_arm_vcpu_arch_get_attr(vcpu, attr); 1062 break; 1063 } 1064 1065 return ret; 1066 } 1067 1068 static int kvm_arm_vcpu_has_attr(struct kvm_vcpu *vcpu, 1069 struct kvm_device_attr *attr) 1070 { 1071 int ret = -ENXIO; 1072 1073 switch (attr->group) { 1074 default: 1075 ret = kvm_arm_vcpu_arch_has_attr(vcpu, attr); 1076 break; 1077 } 1078 1079 return ret; 1080 } 1081 1082 static int kvm_arm_vcpu_get_events(struct kvm_vcpu *vcpu, 1083 struct kvm_vcpu_events *events) 1084 { 1085 memset(events, 0, sizeof(*events)); 1086 1087 return __kvm_arm_vcpu_get_events(vcpu, events); 1088 } 1089 1090 static int kvm_arm_vcpu_set_events(struct kvm_vcpu *vcpu, 1091 struct kvm_vcpu_events *events) 1092 { 1093 int i; 1094 1095 /* check whether the reserved field is zero */ 1096 for (i = 0; i < ARRAY_SIZE(events->reserved); i++) 1097 if (events->reserved[i]) 1098 return -EINVAL; 1099 1100 /* check whether the pad field is zero */ 1101 for (i = 0; i < ARRAY_SIZE(events->exception.pad); i++) 1102 if (events->exception.pad[i]) 1103 return -EINVAL; 1104 1105 return __kvm_arm_vcpu_set_events(vcpu, events); 1106 } 1107 1108 long kvm_arch_vcpu_ioctl(struct file *filp, 1109 unsigned int ioctl, unsigned long arg) 1110 { 1111 struct kvm_vcpu *vcpu = filp->private_data; 1112 void __user *argp = (void __user *)arg; 1113 struct kvm_device_attr attr; 1114 long r; 1115 1116 switch (ioctl) { 1117 case KVM_ARM_VCPU_INIT: { 1118 struct kvm_vcpu_init init; 1119 1120 r = -EFAULT; 1121 if (copy_from_user(&init, argp, sizeof(init))) 1122 break; 1123 1124 r = kvm_arch_vcpu_ioctl_vcpu_init(vcpu, &init); 1125 break; 1126 } 1127 case KVM_SET_ONE_REG: 1128 case KVM_GET_ONE_REG: { 1129 struct kvm_one_reg reg; 1130 1131 r = -ENOEXEC; 1132 if (unlikely(!kvm_vcpu_initialized(vcpu))) 1133 break; 1134 1135 r = -EFAULT; 1136 if (copy_from_user(®, argp, sizeof(reg))) 1137 break; 1138 1139 if (ioctl == KVM_SET_ONE_REG) 1140 r = kvm_arm_set_reg(vcpu, ®); 1141 else 1142 r = kvm_arm_get_reg(vcpu, ®); 1143 break; 1144 } 1145 case KVM_GET_REG_LIST: { 1146 struct kvm_reg_list __user *user_list = argp; 1147 struct kvm_reg_list reg_list; 1148 unsigned n; 1149 1150 r = -ENOEXEC; 1151 if (unlikely(!kvm_vcpu_initialized(vcpu))) 1152 break; 1153 1154 r = -EPERM; 1155 if (!kvm_arm_vcpu_is_finalized(vcpu)) 1156 break; 1157 1158 r = -EFAULT; 1159 if (copy_from_user(®_list, user_list, sizeof(reg_list))) 1160 break; 1161 n = reg_list.n; 1162 reg_list.n = kvm_arm_num_regs(vcpu); 1163 if (copy_to_user(user_list, ®_list, sizeof(reg_list))) 1164 break; 1165 r = -E2BIG; 1166 if (n < reg_list.n) 1167 break; 1168 r = kvm_arm_copy_reg_indices(vcpu, user_list->reg); 1169 break; 1170 } 1171 case KVM_SET_DEVICE_ATTR: { 1172 r = -EFAULT; 1173 if (copy_from_user(&attr, argp, sizeof(attr))) 1174 break; 1175 r = kvm_arm_vcpu_set_attr(vcpu, &attr); 1176 break; 1177 } 1178 case KVM_GET_DEVICE_ATTR: { 1179 r = -EFAULT; 1180 if (copy_from_user(&attr, argp, sizeof(attr))) 1181 break; 1182 r = kvm_arm_vcpu_get_attr(vcpu, &attr); 1183 break; 1184 } 1185 case KVM_HAS_DEVICE_ATTR: { 1186 r = -EFAULT; 1187 if (copy_from_user(&attr, argp, sizeof(attr))) 1188 break; 1189 r = kvm_arm_vcpu_has_attr(vcpu, &attr); 1190 break; 1191 } 1192 case KVM_GET_VCPU_EVENTS: { 1193 struct kvm_vcpu_events events; 1194 1195 if (kvm_arm_vcpu_get_events(vcpu, &events)) 1196 return -EINVAL; 1197 1198 if (copy_to_user(argp, &events, sizeof(events))) 1199 return -EFAULT; 1200 1201 return 0; 1202 } 1203 case KVM_SET_VCPU_EVENTS: { 1204 struct kvm_vcpu_events events; 1205 1206 if (copy_from_user(&events, argp, sizeof(events))) 1207 return -EFAULT; 1208 1209 return kvm_arm_vcpu_set_events(vcpu, &events); 1210 } 1211 case KVM_ARM_VCPU_FINALIZE: { 1212 int what; 1213 1214 if (!kvm_vcpu_initialized(vcpu)) 1215 return -ENOEXEC; 1216 1217 if (get_user(what, (const int __user *)argp)) 1218 return -EFAULT; 1219 1220 return kvm_arm_vcpu_finalize(vcpu, what); 1221 } 1222 default: 1223 r = -EINVAL; 1224 } 1225 1226 return r; 1227 } 1228 1229 void kvm_arch_sync_dirty_log(struct kvm *kvm, struct kvm_memory_slot *memslot) 1230 { 1231 1232 } 1233 1234 void kvm_arch_flush_remote_tlbs_memslot(struct kvm *kvm, 1235 struct kvm_memory_slot *memslot) 1236 { 1237 kvm_flush_remote_tlbs(kvm); 1238 } 1239 1240 static int kvm_vm_ioctl_set_device_addr(struct kvm *kvm, 1241 struct kvm_arm_device_addr *dev_addr) 1242 { 1243 unsigned long dev_id, type; 1244 1245 dev_id = (dev_addr->id & KVM_ARM_DEVICE_ID_MASK) >> 1246 KVM_ARM_DEVICE_ID_SHIFT; 1247 type = (dev_addr->id & KVM_ARM_DEVICE_TYPE_MASK) >> 1248 KVM_ARM_DEVICE_TYPE_SHIFT; 1249 1250 switch (dev_id) { 1251 case KVM_ARM_DEVICE_VGIC_V2: 1252 if (!vgic_present) 1253 return -ENXIO; 1254 return kvm_vgic_addr(kvm, type, &dev_addr->addr, true); 1255 default: 1256 return -ENODEV; 1257 } 1258 } 1259 1260 long kvm_arch_vm_ioctl(struct file *filp, 1261 unsigned int ioctl, unsigned long arg) 1262 { 1263 struct kvm *kvm = filp->private_data; 1264 void __user *argp = (void __user *)arg; 1265 1266 switch (ioctl) { 1267 case KVM_CREATE_IRQCHIP: { 1268 int ret; 1269 if (!vgic_present) 1270 return -ENXIO; 1271 mutex_lock(&kvm->lock); 1272 ret = kvm_vgic_create(kvm, KVM_DEV_TYPE_ARM_VGIC_V2); 1273 mutex_unlock(&kvm->lock); 1274 return ret; 1275 } 1276 case KVM_ARM_SET_DEVICE_ADDR: { 1277 struct kvm_arm_device_addr dev_addr; 1278 1279 if (copy_from_user(&dev_addr, argp, sizeof(dev_addr))) 1280 return -EFAULT; 1281 return kvm_vm_ioctl_set_device_addr(kvm, &dev_addr); 1282 } 1283 case KVM_ARM_PREFERRED_TARGET: { 1284 int err; 1285 struct kvm_vcpu_init init; 1286 1287 err = kvm_vcpu_preferred_target(&init); 1288 if (err) 1289 return err; 1290 1291 if (copy_to_user(argp, &init, sizeof(init))) 1292 return -EFAULT; 1293 1294 return 0; 1295 } 1296 default: 1297 return -EINVAL; 1298 } 1299 } 1300 1301 static unsigned long nvhe_percpu_size(void) 1302 { 1303 return (unsigned long)CHOOSE_NVHE_SYM(__per_cpu_end) - 1304 (unsigned long)CHOOSE_NVHE_SYM(__per_cpu_start); 1305 } 1306 1307 static unsigned long nvhe_percpu_order(void) 1308 { 1309 unsigned long size = nvhe_percpu_size(); 1310 1311 return size ? get_order(size) : 0; 1312 } 1313 1314 static int kvm_map_vectors(void) 1315 { 1316 /* 1317 * SV2 = ARM64_SPECTRE_V2 1318 * HEL2 = ARM64_HARDEN_EL2_VECTORS 1319 * 1320 * !SV2 + !HEL2 -> use direct vectors 1321 * SV2 + !HEL2 -> use hardened vectors in place 1322 * !SV2 + HEL2 -> allocate one vector slot and use exec mapping 1323 * SV2 + HEL2 -> use hardened vectors and use exec mapping 1324 */ 1325 if (cpus_have_const_cap(ARM64_SPECTRE_V2)) { 1326 __kvm_bp_vect_base = kvm_ksym_ref(__bp_harden_hyp_vecs); 1327 __kvm_bp_vect_base = kern_hyp_va(__kvm_bp_vect_base); 1328 } 1329 1330 if (cpus_have_const_cap(ARM64_HARDEN_EL2_VECTORS)) { 1331 phys_addr_t vect_pa = __pa_symbol(__bp_harden_hyp_vecs); 1332 unsigned long size = __BP_HARDEN_HYP_VECS_SZ; 1333 1334 /* 1335 * Always allocate a spare vector slot, as we don't 1336 * know yet which CPUs have a BP hardening slot that 1337 * we can reuse. 1338 */ 1339 __kvm_harden_el2_vector_slot = atomic_inc_return(&arm64_el2_vector_last_slot); 1340 BUG_ON(__kvm_harden_el2_vector_slot >= BP_HARDEN_EL2_SLOTS); 1341 return create_hyp_exec_mappings(vect_pa, size, 1342 &__kvm_bp_vect_base); 1343 } 1344 1345 return 0; 1346 } 1347 1348 static void cpu_init_hyp_mode(void) 1349 { 1350 phys_addr_t pgd_ptr; 1351 unsigned long hyp_stack_ptr; 1352 unsigned long vector_ptr; 1353 unsigned long tpidr_el2; 1354 struct arm_smccc_res res; 1355 1356 /* Switch from the HYP stub to our own HYP init vector */ 1357 __hyp_set_vectors(kvm_get_idmap_vector()); 1358 1359 /* 1360 * Calculate the raw per-cpu offset without a translation from the 1361 * kernel's mapping to the linear mapping, and store it in tpidr_el2 1362 * so that we can use adr_l to access per-cpu variables in EL2. 1363 */ 1364 tpidr_el2 = (unsigned long)this_cpu_ptr_nvhe_sym(__per_cpu_start) - 1365 (unsigned long)kvm_ksym_ref(CHOOSE_NVHE_SYM(__per_cpu_start)); 1366 1367 pgd_ptr = kvm_mmu_get_httbr(); 1368 hyp_stack_ptr = __this_cpu_read(kvm_arm_hyp_stack_page) + PAGE_SIZE; 1369 hyp_stack_ptr = kern_hyp_va(hyp_stack_ptr); 1370 vector_ptr = (unsigned long)kern_hyp_va(kvm_ksym_ref(__kvm_hyp_host_vector)); 1371 1372 /* 1373 * Call initialization code, and switch to the full blown HYP code. 1374 * If the cpucaps haven't been finalized yet, something has gone very 1375 * wrong, and hyp will crash and burn when it uses any 1376 * cpus_have_const_cap() wrapper. 1377 */ 1378 BUG_ON(!system_capabilities_finalized()); 1379 arm_smccc_1_1_hvc(KVM_HOST_SMCCC_FUNC(__kvm_hyp_init), 1380 pgd_ptr, tpidr_el2, hyp_stack_ptr, vector_ptr, &res); 1381 WARN_ON(res.a0 != SMCCC_RET_SUCCESS); 1382 1383 /* 1384 * Disabling SSBD on a non-VHE system requires us to enable SSBS 1385 * at EL2. 1386 */ 1387 if (this_cpu_has_cap(ARM64_SSBS) && 1388 arm64_get_spectre_v4_state() == SPECTRE_VULNERABLE) { 1389 kvm_call_hyp_nvhe(__kvm_enable_ssbs); 1390 } 1391 } 1392 1393 static void cpu_hyp_reset(void) 1394 { 1395 if (!is_kernel_in_hyp_mode()) 1396 __hyp_reset_vectors(); 1397 } 1398 1399 static void cpu_hyp_reinit(void) 1400 { 1401 kvm_init_host_cpu_context(&this_cpu_ptr_hyp_sym(kvm_host_data)->host_ctxt); 1402 1403 cpu_hyp_reset(); 1404 1405 *this_cpu_ptr_hyp_sym(kvm_hyp_vector) = (unsigned long)kvm_get_hyp_vector(); 1406 1407 if (is_kernel_in_hyp_mode()) 1408 kvm_timer_init_vhe(); 1409 else 1410 cpu_init_hyp_mode(); 1411 1412 kvm_arm_init_debug(); 1413 1414 if (vgic_present) 1415 kvm_vgic_init_cpu_hardware(); 1416 } 1417 1418 static void _kvm_arch_hardware_enable(void *discard) 1419 { 1420 if (!__this_cpu_read(kvm_arm_hardware_enabled)) { 1421 cpu_hyp_reinit(); 1422 __this_cpu_write(kvm_arm_hardware_enabled, 1); 1423 } 1424 } 1425 1426 int kvm_arch_hardware_enable(void) 1427 { 1428 _kvm_arch_hardware_enable(NULL); 1429 return 0; 1430 } 1431 1432 static void _kvm_arch_hardware_disable(void *discard) 1433 { 1434 if (__this_cpu_read(kvm_arm_hardware_enabled)) { 1435 cpu_hyp_reset(); 1436 __this_cpu_write(kvm_arm_hardware_enabled, 0); 1437 } 1438 } 1439 1440 void kvm_arch_hardware_disable(void) 1441 { 1442 _kvm_arch_hardware_disable(NULL); 1443 } 1444 1445 #ifdef CONFIG_CPU_PM 1446 static int hyp_init_cpu_pm_notifier(struct notifier_block *self, 1447 unsigned long cmd, 1448 void *v) 1449 { 1450 /* 1451 * kvm_arm_hardware_enabled is left with its old value over 1452 * PM_ENTER->PM_EXIT. It is used to indicate PM_EXIT should 1453 * re-enable hyp. 1454 */ 1455 switch (cmd) { 1456 case CPU_PM_ENTER: 1457 if (__this_cpu_read(kvm_arm_hardware_enabled)) 1458 /* 1459 * don't update kvm_arm_hardware_enabled here 1460 * so that the hardware will be re-enabled 1461 * when we resume. See below. 1462 */ 1463 cpu_hyp_reset(); 1464 1465 return NOTIFY_OK; 1466 case CPU_PM_ENTER_FAILED: 1467 case CPU_PM_EXIT: 1468 if (__this_cpu_read(kvm_arm_hardware_enabled)) 1469 /* The hardware was enabled before suspend. */ 1470 cpu_hyp_reinit(); 1471 1472 return NOTIFY_OK; 1473 1474 default: 1475 return NOTIFY_DONE; 1476 } 1477 } 1478 1479 static struct notifier_block hyp_init_cpu_pm_nb = { 1480 .notifier_call = hyp_init_cpu_pm_notifier, 1481 }; 1482 1483 static void __init hyp_cpu_pm_init(void) 1484 { 1485 cpu_pm_register_notifier(&hyp_init_cpu_pm_nb); 1486 } 1487 static void __init hyp_cpu_pm_exit(void) 1488 { 1489 cpu_pm_unregister_notifier(&hyp_init_cpu_pm_nb); 1490 } 1491 #else 1492 static inline void hyp_cpu_pm_init(void) 1493 { 1494 } 1495 static inline void hyp_cpu_pm_exit(void) 1496 { 1497 } 1498 #endif 1499 1500 static int init_common_resources(void) 1501 { 1502 return kvm_set_ipa_limit(); 1503 } 1504 1505 static int init_subsystems(void) 1506 { 1507 int err = 0; 1508 1509 /* 1510 * Enable hardware so that subsystem initialisation can access EL2. 1511 */ 1512 on_each_cpu(_kvm_arch_hardware_enable, NULL, 1); 1513 1514 /* 1515 * Register CPU lower-power notifier 1516 */ 1517 hyp_cpu_pm_init(); 1518 1519 /* 1520 * Init HYP view of VGIC 1521 */ 1522 err = kvm_vgic_hyp_init(); 1523 switch (err) { 1524 case 0: 1525 vgic_present = true; 1526 break; 1527 case -ENODEV: 1528 case -ENXIO: 1529 vgic_present = false; 1530 err = 0; 1531 break; 1532 default: 1533 goto out; 1534 } 1535 1536 /* 1537 * Init HYP architected timer support 1538 */ 1539 err = kvm_timer_hyp_init(vgic_present); 1540 if (err) 1541 goto out; 1542 1543 kvm_perf_init(); 1544 kvm_coproc_table_init(); 1545 1546 out: 1547 on_each_cpu(_kvm_arch_hardware_disable, NULL, 1); 1548 1549 return err; 1550 } 1551 1552 static void teardown_hyp_mode(void) 1553 { 1554 int cpu; 1555 1556 free_hyp_pgds(); 1557 for_each_possible_cpu(cpu) { 1558 free_page(per_cpu(kvm_arm_hyp_stack_page, cpu)); 1559 free_pages(kvm_arm_hyp_percpu_base[cpu], nvhe_percpu_order()); 1560 } 1561 } 1562 1563 /** 1564 * Inits Hyp-mode on all online CPUs 1565 */ 1566 static int init_hyp_mode(void) 1567 { 1568 int cpu; 1569 int err = 0; 1570 1571 /* 1572 * Allocate Hyp PGD and setup Hyp identity mapping 1573 */ 1574 err = kvm_mmu_init(); 1575 if (err) 1576 goto out_err; 1577 1578 /* 1579 * Allocate stack pages for Hypervisor-mode 1580 */ 1581 for_each_possible_cpu(cpu) { 1582 unsigned long stack_page; 1583 1584 stack_page = __get_free_page(GFP_KERNEL); 1585 if (!stack_page) { 1586 err = -ENOMEM; 1587 goto out_err; 1588 } 1589 1590 per_cpu(kvm_arm_hyp_stack_page, cpu) = stack_page; 1591 } 1592 1593 /* 1594 * Allocate and initialize pages for Hypervisor-mode percpu regions. 1595 */ 1596 for_each_possible_cpu(cpu) { 1597 struct page *page; 1598 void *page_addr; 1599 1600 page = alloc_pages(GFP_KERNEL, nvhe_percpu_order()); 1601 if (!page) { 1602 err = -ENOMEM; 1603 goto out_err; 1604 } 1605 1606 page_addr = page_address(page); 1607 memcpy(page_addr, CHOOSE_NVHE_SYM(__per_cpu_start), nvhe_percpu_size()); 1608 kvm_arm_hyp_percpu_base[cpu] = (unsigned long)page_addr; 1609 } 1610 1611 /* 1612 * Map the Hyp-code called directly from the host 1613 */ 1614 err = create_hyp_mappings(kvm_ksym_ref(__hyp_text_start), 1615 kvm_ksym_ref(__hyp_text_end), PAGE_HYP_EXEC); 1616 if (err) { 1617 kvm_err("Cannot map world-switch code\n"); 1618 goto out_err; 1619 } 1620 1621 err = create_hyp_mappings(kvm_ksym_ref(__start_rodata), 1622 kvm_ksym_ref(__end_rodata), PAGE_HYP_RO); 1623 if (err) { 1624 kvm_err("Cannot map rodata section\n"); 1625 goto out_err; 1626 } 1627 1628 err = create_hyp_mappings(kvm_ksym_ref(__bss_start), 1629 kvm_ksym_ref(__bss_stop), PAGE_HYP_RO); 1630 if (err) { 1631 kvm_err("Cannot map bss section\n"); 1632 goto out_err; 1633 } 1634 1635 err = kvm_map_vectors(); 1636 if (err) { 1637 kvm_err("Cannot map vectors\n"); 1638 goto out_err; 1639 } 1640 1641 /* 1642 * Map the Hyp stack pages 1643 */ 1644 for_each_possible_cpu(cpu) { 1645 char *stack_page = (char *)per_cpu(kvm_arm_hyp_stack_page, cpu); 1646 err = create_hyp_mappings(stack_page, stack_page + PAGE_SIZE, 1647 PAGE_HYP); 1648 1649 if (err) { 1650 kvm_err("Cannot map hyp stack\n"); 1651 goto out_err; 1652 } 1653 } 1654 1655 /* 1656 * Map Hyp percpu pages 1657 */ 1658 for_each_possible_cpu(cpu) { 1659 char *percpu_begin = (char *)kvm_arm_hyp_percpu_base[cpu]; 1660 char *percpu_end = percpu_begin + nvhe_percpu_size(); 1661 1662 err = create_hyp_mappings(percpu_begin, percpu_end, PAGE_HYP); 1663 1664 if (err) { 1665 kvm_err("Cannot map hyp percpu region\n"); 1666 goto out_err; 1667 } 1668 } 1669 1670 return 0; 1671 1672 out_err: 1673 teardown_hyp_mode(); 1674 kvm_err("error initializing Hyp mode: %d\n", err); 1675 return err; 1676 } 1677 1678 static void check_kvm_target_cpu(void *ret) 1679 { 1680 *(int *)ret = kvm_target_cpu(); 1681 } 1682 1683 struct kvm_vcpu *kvm_mpidr_to_vcpu(struct kvm *kvm, unsigned long mpidr) 1684 { 1685 struct kvm_vcpu *vcpu; 1686 int i; 1687 1688 mpidr &= MPIDR_HWID_BITMASK; 1689 kvm_for_each_vcpu(i, vcpu, kvm) { 1690 if (mpidr == kvm_vcpu_get_mpidr_aff(vcpu)) 1691 return vcpu; 1692 } 1693 return NULL; 1694 } 1695 1696 bool kvm_arch_has_irq_bypass(void) 1697 { 1698 return true; 1699 } 1700 1701 int kvm_arch_irq_bypass_add_producer(struct irq_bypass_consumer *cons, 1702 struct irq_bypass_producer *prod) 1703 { 1704 struct kvm_kernel_irqfd *irqfd = 1705 container_of(cons, struct kvm_kernel_irqfd, consumer); 1706 1707 return kvm_vgic_v4_set_forwarding(irqfd->kvm, prod->irq, 1708 &irqfd->irq_entry); 1709 } 1710 void kvm_arch_irq_bypass_del_producer(struct irq_bypass_consumer *cons, 1711 struct irq_bypass_producer *prod) 1712 { 1713 struct kvm_kernel_irqfd *irqfd = 1714 container_of(cons, struct kvm_kernel_irqfd, consumer); 1715 1716 kvm_vgic_v4_unset_forwarding(irqfd->kvm, prod->irq, 1717 &irqfd->irq_entry); 1718 } 1719 1720 void kvm_arch_irq_bypass_stop(struct irq_bypass_consumer *cons) 1721 { 1722 struct kvm_kernel_irqfd *irqfd = 1723 container_of(cons, struct kvm_kernel_irqfd, consumer); 1724 1725 kvm_arm_halt_guest(irqfd->kvm); 1726 } 1727 1728 void kvm_arch_irq_bypass_start(struct irq_bypass_consumer *cons) 1729 { 1730 struct kvm_kernel_irqfd *irqfd = 1731 container_of(cons, struct kvm_kernel_irqfd, consumer); 1732 1733 kvm_arm_resume_guest(irqfd->kvm); 1734 } 1735 1736 /** 1737 * Initialize Hyp-mode and memory mappings on all CPUs. 1738 */ 1739 int kvm_arch_init(void *opaque) 1740 { 1741 int err; 1742 int ret, cpu; 1743 bool in_hyp_mode; 1744 1745 if (!is_hyp_mode_available()) { 1746 kvm_info("HYP mode not available\n"); 1747 return -ENODEV; 1748 } 1749 1750 in_hyp_mode = is_kernel_in_hyp_mode(); 1751 1752 if (!in_hyp_mode && kvm_arch_requires_vhe()) { 1753 kvm_pr_unimpl("CPU unsupported in non-VHE mode, not initializing\n"); 1754 return -ENODEV; 1755 } 1756 1757 if (cpus_have_final_cap(ARM64_WORKAROUND_DEVICE_LOAD_ACQUIRE) || 1758 cpus_have_final_cap(ARM64_WORKAROUND_1508412)) 1759 kvm_info("Guests without required CPU erratum workarounds can deadlock system!\n" \ 1760 "Only trusted guests should be used on this system.\n"); 1761 1762 for_each_online_cpu(cpu) { 1763 smp_call_function_single(cpu, check_kvm_target_cpu, &ret, 1); 1764 if (ret < 0) { 1765 kvm_err("Error, CPU %d not supported!\n", cpu); 1766 return -ENODEV; 1767 } 1768 } 1769 1770 err = init_common_resources(); 1771 if (err) 1772 return err; 1773 1774 err = kvm_arm_init_sve(); 1775 if (err) 1776 return err; 1777 1778 if (!in_hyp_mode) { 1779 err = init_hyp_mode(); 1780 if (err) 1781 goto out_err; 1782 } 1783 1784 err = init_subsystems(); 1785 if (err) 1786 goto out_hyp; 1787 1788 if (in_hyp_mode) 1789 kvm_info("VHE mode initialized successfully\n"); 1790 else 1791 kvm_info("Hyp mode initialized successfully\n"); 1792 1793 return 0; 1794 1795 out_hyp: 1796 hyp_cpu_pm_exit(); 1797 if (!in_hyp_mode) 1798 teardown_hyp_mode(); 1799 out_err: 1800 return err; 1801 } 1802 1803 /* NOP: Compiling as a module not supported */ 1804 void kvm_arch_exit(void) 1805 { 1806 kvm_perf_teardown(); 1807 } 1808 1809 static int arm_init(void) 1810 { 1811 int rc = kvm_init(NULL, sizeof(struct kvm_vcpu), 0, THIS_MODULE); 1812 return rc; 1813 } 1814 1815 module_init(arm_init); 1816