virt/kvm/kvm_main.c

   1 /*
   2  * Kernel-based Virtual Machine driver for Linux
   3  *
   4  * This module enables machines with Intel VT-x extensions to run virtual
   5  * machines without emulation or binary translation.
   6  *
   7  * Copyright (C) 2006 Qumranet, Inc.
   8  *
   9  * Authors:
  10  *   Avi Kivity   <avi@qumranet.com>
  11  *   Yaniv Kamay  <yaniv@qumranet.com>
  12  *
  13  * This work is licensed under the terms of the GNU GPL, version 2.  See
  14  * the COPYING file in the top-level directory.
  15  *
  16  */
  17
  18 #include "iodev.h"
  19
  20 #include <linux/kvm_host.h>
  21 #include <linux/kvm.h>
  22 #include <linux/module.h>
  23 #include <linux/errno.h>
  24 #include <linux/percpu.h>
  25 #include <linux/gfp.h>
  26 #include <linux/mm.h>
  27 #include <linux/miscdevice.h>
  28 #include <linux/vmalloc.h>
  29 #include <linux/reboot.h>
  30 #include <linux/debugfs.h>
  31 #include <linux/highmem.h>
  32 #include <linux/file.h>
  33 #include <linux/sysdev.h>
  34 #include <linux/cpu.h>
  35 #include <linux/sched.h>
  36 #include <linux/cpumask.h>
  37 #include <linux/smp.h>
  38 #include <linux/anon_inodes.h>
  39 #include <linux/profile.h>
  40 #include <linux/kvm_para.h>
  41 #include <linux/pagemap.h>
  42 #include <linux/mman.h>
  43
  44 #include <asm/processor.h>
  45 #include <asm/io.h>
  46 #include <asm/uaccess.h>
  47 #include <asm/pgtable.h>
  48
  49 MODULE_AUTHOR("Qumranet");
  50 MODULE_LICENSE("GPL");
  51
  52 DEFINE_SPINLOCK(kvm_lock);
  53 LIST_HEAD(vm_list);
  54
  55 static cpumask_t cpus_hardware_enabled;
  56
  57 struct kmem_cache *kvm_vcpu_cache;
  58 EXPORT_SYMBOL_GPL(kvm_vcpu_cache);
  59
  60 static __read_mostly struct preempt_ops kvm_preempt_ops;
  61
  62 static struct dentry *debugfs_dir;
  63
  64 static long kvm_vcpu_ioctl(struct file *file, unsigned int ioctl,
  65                            unsigned long arg);
  66
  67 static inline int valid_vcpu(int n)
  68 {
  69         return likely(n >= 0 && n < KVM_MAX_VCPUS);
  70 }
  71
  72 /*
  73  * Switches to specified vcpu, until a matching vcpu_put()
  74  */
  75 void vcpu_load(struct kvm_vcpu *vcpu)
  76 {
  77         int cpu;
  78
  79         mutex_lock(&vcpu->mutex);
  80         cpu = get_cpu();
  81         preempt_notifier_register(&vcpu->preempt_notifier);
  82         kvm_arch_vcpu_load(vcpu, cpu);
  83         put_cpu();
  84 }
  85
  86 void vcpu_put(struct kvm_vcpu *vcpu)
  87 {
  88         preempt_disable();
  89         kvm_arch_vcpu_put(vcpu);
  90         preempt_notifier_unregister(&vcpu->preempt_notifier);
  91         preempt_enable();
  92         mutex_unlock(&vcpu->mutex);
  93 }
  94
  95 static void ack_flush(void *_completed)
  96 {
  97 }
  98
  99 void kvm_flush_remote_tlbs(struct kvm *kvm)
 100 {
 101         int i, cpu;
 102         cpumask_t cpus;
 103         struct kvm_vcpu *vcpu;
 104
 105         cpus_clear(cpus);
 106         for (i = 0; i < KVM_MAX_VCPUS; ++i) {
 107                 vcpu = kvm->vcpus[i];
 108                 if (!vcpu)
 109                         continue;
 110                 if (test_and_set_bit(KVM_REQ_TLB_FLUSH, &vcpu->requests))
 111                         continue;
 112                 cpu = vcpu->cpu;
 113                 if (cpu != -1 && cpu != raw_smp_processor_id())
 114                         cpu_set(cpu, cpus);
 115         }
 116         if (cpus_empty(cpus))
 117                 return;
 118         ++kvm->stat.remote_tlb_flush;
 119         smp_call_function_mask(cpus, ack_flush, NULL, 1);
 120 }
 121
 122 int kvm_vcpu_init(struct kvm_vcpu *vcpu, struct kvm *kvm, unsigned id)
 123 {
 124         struct page *page;
 125         int r;
 126
 127         mutex_init(&vcpu->mutex);
 128         vcpu->cpu = -1;
 129         vcpu->kvm = kvm;
 130         vcpu->vcpu_id = id;
 131         init_waitqueue_head(&vcpu->wq);
 132
 133         page = alloc_page(GFP_KERNEL | __GFP_ZERO);
 134         if (!page) {
 135                 r = -ENOMEM;
 136                 goto fail;
 137         }
 138         vcpu->run = page_address(page);
 139
 140         r = kvm_arch_vcpu_init(vcpu);
 141         if (r < 0)
 142                 goto fail_free_run;
 143         return 0;
 144
 145 fail_free_run:
 146         free_page((unsigned long)vcpu->run);
 147 fail:
 148         return r;
 149 }
 150 EXPORT_SYMBOL_GPL(kvm_vcpu_init);
 151
 152 void kvm_vcpu_uninit(struct kvm_vcpu *vcpu)
 153 {
 154         kvm_arch_vcpu_uninit(vcpu);
 155         free_page((unsigned long)vcpu->run);
 156 }
 157 EXPORT_SYMBOL_GPL(kvm_vcpu_uninit);
 158
 159 static struct kvm *kvm_create_vm(void)
 160 {
 161         struct kvm *kvm = kvm_arch_create_vm();
 162
 163         if (IS_ERR(kvm))
 164                 goto out;
 165
 166         kvm->mm = current->mm;
 167         atomic_inc(&kvm->mm->mm_count);
 168         spin_lock_init(&kvm->mmu_lock);
 169         kvm_io_bus_init(&kvm->pio_bus);
 170         mutex_init(&kvm->lock);
 171         kvm_io_bus_init(&kvm->mmio_bus);
 172         init_rwsem(&kvm->slots_lock);
 173         spin_lock(&kvm_lock);
 174         list_add(&kvm->vm_list, &vm_list);
 175         spin_unlock(&kvm_lock);
 176 out:
 177         return kvm;
 178 }
 179
 180 /*
 181  * Free any memory in @free but not in @dont.
 182  */
 183 static void kvm_free_physmem_slot(struct kvm_memory_slot *free,
 184                                   struct kvm_memory_slot *dont)
 185 {
 186         if (!dont || free->rmap != dont->rmap)
 187                 vfree(free->rmap);
 188
 189         if (!dont || free->dirty_bitmap != dont->dirty_bitmap)
 190                 vfree(free->dirty_bitmap);
 191
 192         free->npages = 0;
 193         free->dirty_bitmap = NULL;
 194         free->rmap = NULL;
 195 }
 196
 197 void kvm_free_physmem(struct kvm *kvm)
 198 {
 199         int i;
 200
 201         for (i = 0; i < kvm->nmemslots; ++i)
 202                 kvm_free_physmem_slot(&kvm->memslots[i], NULL);
 203 }
 204
 205 static void kvm_destroy_vm(struct kvm *kvm)
 206 {
 207         struct mm_struct *mm = kvm->mm;
 208
 209         spin_lock(&kvm_lock);
 210         list_del(&kvm->vm_list);
 211         spin_unlock(&kvm_lock);
 212         kvm_io_bus_destroy(&kvm->pio_bus);
 213         kvm_io_bus_destroy(&kvm->mmio_bus);
 214         kvm_arch_destroy_vm(kvm);
 215         mmdrop(mm);
 216 }
 217
 218 static int kvm_vm_release(struct inode *inode, struct file *filp)
 219 {
 220         struct kvm *kvm = filp->private_data;
 221
 222         kvm_destroy_vm(kvm);
 223         return 0;
 224 }
 225
 226 /*
 227  * Allocate some memory and give it an address in the guest physical address
 228  * space.
 229  *
 230  * Discontiguous memory is allowed, mostly for framebuffers.
 231  *
 232  * Must be called holding mmap_sem for write.
 233  */
 234 int __kvm_set_memory_region(struct kvm *kvm,
 235                             struct kvm_userspace_memory_region *mem,
 236                             int user_alloc)
 237 {
 238         int r;
 239         gfn_t base_gfn;
 240         unsigned long npages;
 241         unsigned long i;
 242         struct kvm_memory_slot *memslot;
 243         struct kvm_memory_slot old, new;
 244
 245         r = -EINVAL;
 246         /* General sanity checks */
 247         if (mem->memory_size & (PAGE_SIZE - 1))
 248                 goto out;
 249         if (mem->guest_phys_addr & (PAGE_SIZE - 1))
 250                 goto out;
 251         if (mem->slot >= KVM_MEMORY_SLOTS + KVM_PRIVATE_MEM_SLOTS)
 252                 goto out;
 253         if (mem->guest_phys_addr + mem->memory_size < mem->guest_phys_addr)
 254                 goto out;
 255
 256         memslot = &kvm->memslots[mem->slot];
 257         base_gfn = mem->guest_phys_addr >> PAGE_SHIFT;
 258         npages = mem->memory_size >> PAGE_SHIFT;
 259
 260         if (!npages)
 261                 mem->flags &= ~KVM_MEM_LOG_DIRTY_PAGES;
 262
 263         new = old = *memslot;
 264
 265         new.base_gfn = base_gfn;
 266         new.npages = npages;
 267         new.flags = mem->flags;
 268
 269         /* Disallow changing a memory slot's size. */
 270         r = -EINVAL;
 271         if (npages && old.npages && npages != old.npages)
 272                 goto out_free;
 273
 274         /* Check for overlaps */
 275         r = -EEXIST;
 276         for (i = 0; i < KVM_MEMORY_SLOTS; ++i) {
 277                 struct kvm_memory_slot *s = &kvm->memslots[i];
 278
 279                 if (s == memslot)
 280                         continue;
 281                 if (!((base_gfn + npages <= s->base_gfn) ||
 282                       (base_gfn >= s->base_gfn + s->npages)))
 283                         goto out_free;
 284         }
 285
 286         /* Free page dirty bitmap if unneeded */
 287         if (!(new.flags & KVM_MEM_LOG_DIRTY_PAGES))
 288                 new.dirty_bitmap = NULL;
 289
 290         r = -ENOMEM;
 291
 292         /* Allocate if a slot is being created */
 293         if (npages && !new.rmap) {
 294                 new.rmap = vmalloc(npages * sizeof(struct page *));
 295
 296                 if (!new.rmap)
 297                         goto out_free;
 298
 299                 memset(new.rmap, 0, npages * sizeof(*new.rmap));
 300
 301                 new.user_alloc = user_alloc;
 302                 new.userspace_addr = mem->userspace_addr;
 303         }
 304
 305         /* Allocate page dirty bitmap if needed */
 306         if ((new.flags & KVM_MEM_LOG_DIRTY_PAGES) && !new.dirty_bitmap) {
 307                 unsigned dirty_bytes = ALIGN(npages, BITS_PER_LONG) / 8;
 308
 309                 new.dirty_bitmap = vmalloc(dirty_bytes);
 310                 if (!new.dirty_bitmap)
 311                         goto out_free;
 312                 memset(new.dirty_bitmap, 0, dirty_bytes);
 313         }
 314
 315         if (mem->slot >= kvm->nmemslots)
 316                 kvm->nmemslots = mem->slot + 1;
 317
 318         *memslot = new;
 319
 320         r = kvm_arch_set_memory_region(kvm, mem, old, user_alloc);
 321         if (r) {
 322                 *memslot = old;
 323                 goto out_free;
 324         }
 325
 326         kvm_free_physmem_slot(&old, &new);
 327         return 0;
 328
 329 out_free:
 330         kvm_free_physmem_slot(&new, &old);
 331 out:
 332         return r;
 333
 334 }
 335 EXPORT_SYMBOL_GPL(__kvm_set_memory_region);
 336
 337 int kvm_set_memory_region(struct kvm *kvm,
 338                           struct kvm_userspace_memory_region *mem,
 339                           int user_alloc)
 340 {
 341         int r;
 342
 343         down_write(&kvm->slots_lock);
 344         r = __kvm_set_memory_region(kvm, mem, user_alloc);
 345         up_write(&kvm->slots_lock);
 346         return r;
 347 }
 348 EXPORT_SYMBOL_GPL(kvm_set_memory_region);
 349
 350 int kvm_vm_ioctl_set_memory_region(struct kvm *kvm,
 351                                    struct
 352                                    kvm_userspace_memory_region *mem,
 353                                    int user_alloc)
 354 {
 355         if (mem->slot >= KVM_MEMORY_SLOTS)
 356                 return -EINVAL;
 357         return kvm_set_memory_region(kvm, mem, user_alloc);
 358 }
 359
 360 int kvm_get_dirty_log(struct kvm *kvm,
 361                         struct kvm_dirty_log *log, int *is_dirty)
 362 {
 363         struct kvm_memory_slot *memslot;
 364         int r, i;
 365         int n;
 366         unsigned long any = 0;
 367
 368         r = -EINVAL;
 369         if (log->slot >= KVM_MEMORY_SLOTS)
 370                 goto out;
 371
 372         memslot = &kvm->memslots[log->slot];
 373         r = -ENOENT;
 374         if (!memslot->dirty_bitmap)
 375                 goto out;
 376
 377         n = ALIGN(memslot->npages, BITS_PER_LONG) / 8;
 378
 379         for (i = 0; !any && i < n/sizeof(long); ++i)
 380                 any = memslot->dirty_bitmap[i];
 381
 382         r = -EFAULT;
 383         if (copy_to_user(log->dirty_bitmap, memslot->dirty_bitmap, n))
 384                 goto out;
 385
 386         if (any)
 387                 *is_dirty = 1;
 388
 389         r = 0;
 390 out:
 391         return r;
 392 }
 393
 394 int is_error_page(struct page *page)
 395 {
 396         return page == bad_page;
 397 }
 398 EXPORT_SYMBOL_GPL(is_error_page);
 399
 400 static inline unsigned long bad_hva(void)
 401 {
 402         return PAGE_OFFSET;
 403 }
 404
 405 int kvm_is_error_hva(unsigned long addr)
 406 {
 407         return addr == bad_hva();
 408 }
 409 EXPORT_SYMBOL_GPL(kvm_is_error_hva);
 410
 411 static struct kvm_memory_slot *__gfn_to_memslot(struct kvm *kvm, gfn_t gfn)
 412 {
 413         int i;
 414
 415         for (i = 0; i < kvm->nmemslots; ++i) {
 416                 struct kvm_memory_slot *memslot = &kvm->memslots[i];
 417
 418                 if (gfn >= memslot->base_gfn
 419                     && gfn < memslot->base_gfn + memslot->npages)
 420                         return memslot;
 421         }
 422         return NULL;
 423 }
 424
 425 struct kvm_memory_slot *gfn_to_memslot(struct kvm *kvm, gfn_t gfn)
 426 {
 427         gfn = unalias_gfn(kvm, gfn);
 428         return __gfn_to_memslot(kvm, gfn);
 429 }
 430
 431 int kvm_is_visible_gfn(struct kvm *kvm, gfn_t gfn)
 432 {
 433         int i;
 434
 435         gfn = unalias_gfn(kvm, gfn);
 436         for (i = 0; i < KVM_MEMORY_SLOTS; ++i) {
 437                 struct kvm_memory_slot *memslot = &kvm->memslots[i];
 438
 439                 if (gfn >= memslot->base_gfn
 440                     && gfn < memslot->base_gfn + memslot->npages)
 441                         return 1;
 442         }
 443         return 0;
 444 }
 445 EXPORT_SYMBOL_GPL(kvm_is_visible_gfn);
 446
 447 static unsigned long gfn_to_hva(struct kvm *kvm, gfn_t gfn)
 448 {
 449         struct kvm_memory_slot *slot;
 450
 451         gfn = unalias_gfn(kvm, gfn);
 452         slot = __gfn_to_memslot(kvm, gfn);
 453         if (!slot)
 454                 return bad_hva();
 455         return (slot->userspace_addr + (gfn - slot->base_gfn) * PAGE_SIZE);
 456 }
 457
 458 /*
 459  * Requires current->mm->mmap_sem to be held
 460  */
 461 struct page *gfn_to_page(struct kvm *kvm, gfn_t gfn)
 462 {
 463         struct page *page[1];
 464         unsigned long addr;
 465         int npages;
 466
 467         might_sleep();
 468
 469         addr = gfn_to_hva(kvm, gfn);
 470         if (kvm_is_error_hva(addr)) {
 471                 get_page(bad_page);
 472                 return bad_page;
 473         }
 474
 475         npages = get_user_pages(current, current->mm, addr, 1, 1, 1, page,
 476                                 NULL);
 477
 478         if (npages != 1) {
 479                 get_page(bad_page);
 480                 return bad_page;
 481         }
 482
 483         return page[0];
 484 }
 485
 486 EXPORT_SYMBOL_GPL(gfn_to_page);
 487
 488 void kvm_release_page_clean(struct page *page)
 489 {
 490         put_page(page);
 491 }
 492 EXPORT_SYMBOL_GPL(kvm_release_page_clean);
 493
 494 void kvm_release_page_dirty(struct page *page)
 495 {
 496         if (!PageReserved(page))
 497                 SetPageDirty(page);
 498         put_page(page);
 499 }
 500 EXPORT_SYMBOL_GPL(kvm_release_page_dirty);
 501
 502 static int next_segment(unsigned long len, int offset)
 503 {
 504         if (len > PAGE_SIZE - offset)
 505                 return PAGE_SIZE - offset;
 506         else
 507                 return len;
 508 }
 509
 510 int kvm_read_guest_page(struct kvm *kvm, gfn_t gfn, void *data, int offset,
 511                         int len)
 512 {
 513         int r;
 514         unsigned long addr;
 515
 516         addr = gfn_to_hva(kvm, gfn);
 517         if (kvm_is_error_hva(addr))
 518                 return -EFAULT;
 519         r = copy_from_user(data, (void __user *)addr + offset, len);
 520         if (r)
 521                 return -EFAULT;
 522         return 0;
 523 }
 524 EXPORT_SYMBOL_GPL(kvm_read_guest_page);
 525
 526 int kvm_read_guest(struct kvm *kvm, gpa_t gpa, void *data, unsigned long len)
 527 {
 528         gfn_t gfn = gpa >> PAGE_SHIFT;
 529         int seg;
 530         int offset = offset_in_page(gpa);
 531         int ret;
 532
 533         while ((seg = next_segment(len, offset)) != 0) {
 534                 ret = kvm_read_guest_page(kvm, gfn, data, offset, seg);
 535                 if (ret < 0)
 536                         return ret;
 537                 offset = 0;
 538                 len -= seg;
 539                 data += seg;
 540                 ++gfn;
 541         }
 542         return 0;
 543 }
 544 EXPORT_SYMBOL_GPL(kvm_read_guest);
 545
 546 int kvm_read_guest_atomic(struct kvm *kvm, gpa_t gpa, void *data,
 547                           unsigned long len)
 548 {
 549         int r;
 550         unsigned long addr;
 551         gfn_t gfn = gpa >> PAGE_SHIFT;
 552         int offset = offset_in_page(gpa);
 553
 554         addr = gfn_to_hva(kvm, gfn);
 555         if (kvm_is_error_hva(addr))
 556                 return -EFAULT;
 557         r = __copy_from_user_inatomic(data, (void __user *)addr + offset, len);
 558         if (r)
 559                 return -EFAULT;
 560         return 0;
 561 }
 562 EXPORT_SYMBOL(kvm_read_guest_atomic);
 563
 564 int kvm_write_guest_page(struct kvm *kvm, gfn_t gfn, const void *data,
 565                          int offset, int len)
 566 {
 567         int r;
 568         unsigned long addr;
 569
 570         addr = gfn_to_hva(kvm, gfn);
 571         if (kvm_is_error_hva(addr))
 572                 return -EFAULT;
 573         r = copy_to_user((void __user *)addr + offset, data, len);
 574         if (r)
 575                 return -EFAULT;
 576         mark_page_dirty(kvm, gfn);
 577         return 0;
 578 }
 579 EXPORT_SYMBOL_GPL(kvm_write_guest_page);
 580
 581 int kvm_write_guest(struct kvm *kvm, gpa_t gpa, const void *data,
 582                     unsigned long len)
 583 {
 584         gfn_t gfn = gpa >> PAGE_SHIFT;
 585         int seg;
 586         int offset = offset_in_page(gpa);
 587         int ret;
 588
 589         while ((seg = next_segment(len, offset)) != 0) {
 590                 ret = kvm_write_guest_page(kvm, gfn, data, offset, seg);
 591                 if (ret < 0)
 592                         return ret;
 593                 offset = 0;
 594                 len -= seg;
 595                 data += seg;
 596                 ++gfn;
 597         }
 598         return 0;
 599 }
 600
 601 int kvm_clear_guest_page(struct kvm *kvm, gfn_t gfn, int offset, int len)
 602 {
 603         return kvm_write_guest_page(kvm, gfn, empty_zero_page, offset, len);
 604 }
 605 EXPORT_SYMBOL_GPL(kvm_clear_guest_page);
 606
 607 int kvm_clear_guest(struct kvm *kvm, gpa_t gpa, unsigned long len)
 608 {
 609         gfn_t gfn = gpa >> PAGE_SHIFT;
 610         int seg;
 611         int offset = offset_in_page(gpa);
 612         int ret;
 613
 614         while ((seg = next_segment(len, offset)) != 0) {
 615                 ret = kvm_clear_guest_page(kvm, gfn, offset, seg);
 616                 if (ret < 0)
 617                         return ret;
 618                 offset = 0;
 619                 len -= seg;
 620                 ++gfn;
 621         }
 622         return 0;
 623 }
 624 EXPORT_SYMBOL_GPL(kvm_clear_guest);
 625
 626 void mark_page_dirty(struct kvm *kvm, gfn_t gfn)
 627 {
 628         struct kvm_memory_slot *memslot;
 629
 630         gfn = unalias_gfn(kvm, gfn);
 631         memslot = __gfn_to_memslot(kvm, gfn);
 632         if (memslot && memslot->dirty_bitmap) {
 633                 unsigned long rel_gfn = gfn - memslot->base_gfn;
 634
 635                 /* avoid RMW */
 636                 if (!test_bit(rel_gfn, memslot->dirty_bitmap))
 637                         set_bit(rel_gfn, memslot->dirty_bitmap);
 638         }
 639 }
 640
 641 /*
 642  * The vCPU has executed a HLT instruction with in-kernel mode enabled.
 643  */
 644 void kvm_vcpu_block(struct kvm_vcpu *vcpu)
 645 {
 646         DECLARE_WAITQUEUE(wait, current);
 647
 648         add_wait_queue(&vcpu->wq, &wait);
 649
 650         /*
 651          * We will block until either an interrupt or a signal wakes us up
 652          */
 653         while (!kvm_cpu_has_interrupt(vcpu)
 654                && !signal_pending(current)
 655                && !kvm_arch_vcpu_runnable(vcpu)) {
 656                 set_current_state(TASK_INTERRUPTIBLE);
 657                 vcpu_put(vcpu);
 658                 schedule();
 659                 vcpu_load(vcpu);
 660         }
 661
 662         __set_current_state(TASK_RUNNING);
 663         remove_wait_queue(&vcpu->wq, &wait);
 664 }
 665
 666 void kvm_resched(struct kvm_vcpu *vcpu)
 667 {
 668         if (!need_resched())
 669                 return;
 670         cond_resched();
 671 }
 672 EXPORT_SYMBOL_GPL(kvm_resched);
 673
 674 static int kvm_vcpu_fault(struct vm_area_struct *vma, struct vm_fault *vmf)
 675 {
 676         struct kvm_vcpu *vcpu = vma->vm_file->private_data;
 677         struct page *page;
 678
 679         if (vmf->pgoff == 0)
 680                 page = virt_to_page(vcpu->run);
 681 #ifdef CONFIG_X86
 682         else if (vmf->pgoff == KVM_PIO_PAGE_OFFSET)
 683                 page = virt_to_page(vcpu->arch.pio_data);
 684 #endif
 685         else
 686                 return VM_FAULT_SIGBUS;
 687         get_page(page);
 688         vmf->page = page;
 689         return 0;
 690 }
 691
 692 static struct vm_operations_struct kvm_vcpu_vm_ops = {
 693         .fault = kvm_vcpu_fault,
 694 };
 695
 696 static int kvm_vcpu_mmap(struct file *file, struct vm_area_struct *vma)
 697 {
 698         vma->vm_ops = &kvm_vcpu_vm_ops;
 699         return 0;
 700 }
 701
 702 static int kvm_vcpu_release(struct inode *inode, struct file *filp)
 703 {
 704         struct kvm_vcpu *vcpu = filp->private_data;
 705
 706         fput(vcpu->kvm->filp);
 707         return 0;
 708 }
 709
 710 static const struct file_operations kvm_vcpu_fops = {
 711         .release        = kvm_vcpu_release,
 712         .unlocked_ioctl = kvm_vcpu_ioctl,
 713         .compat_ioctl   = kvm_vcpu_ioctl,
 714         .mmap           = kvm_vcpu_mmap,
 715 };
 716
 717 /*
 718  * Allocates an inode for the vcpu.
 719  */
 720 static int create_vcpu_fd(struct kvm_vcpu *vcpu)
 721 {
 722         int fd, r;
 723         struct inode *inode;
 724         struct file *file;
 725
 726         r = anon_inode_getfd(&fd, &inode, &file,
 727                              "kvm-vcpu", &kvm_vcpu_fops, vcpu);
 728         if (r)
 729                 return r;
 730         atomic_inc(&vcpu->kvm->filp->f_count);
 731         return fd;
 732 }
 733
 734 /*
 735  * Creates some virtual cpus.  Good luck creating more than one.
 736  */
 737 static int kvm_vm_ioctl_create_vcpu(struct kvm *kvm, int n)
 738 {
 739         int r;
 740         struct kvm_vcpu *vcpu;
 741
 742         if (!valid_vcpu(n))
 743                 return -EINVAL;
 744
 745         vcpu = kvm_arch_vcpu_create(kvm, n);
 746         if (IS_ERR(vcpu))
 747                 return PTR_ERR(vcpu);
 748
 749         preempt_notifier_init(&vcpu->preempt_notifier, &kvm_preempt_ops);
 750
 751         r = kvm_arch_vcpu_setup(vcpu);
 752         if (r)
 753                 goto vcpu_destroy;
 754
 755         mutex_lock(&kvm->lock);
 756         if (kvm->vcpus[n]) {
 757                 r = -EEXIST;
 758                 mutex_unlock(&kvm->lock);
 759                 goto vcpu_destroy;
 760         }
 761         kvm->vcpus[n] = vcpu;
 762         mutex_unlock(&kvm->lock);
 763
 764         /* Now it's all set up, let userspace reach it */
 765         r = create_vcpu_fd(vcpu);
 766         if (r < 0)
 767                 goto unlink;
 768         return r;
 769
 770 unlink:
 771         mutex_lock(&kvm->lock);
 772         kvm->vcpus[n] = NULL;
 773         mutex_unlock(&kvm->lock);
 774 vcpu_destroy:
 775         kvm_arch_vcpu_destroy(vcpu);
 776         return r;
 777 }
 778
 779 static int kvm_vcpu_ioctl_set_sigmask(struct kvm_vcpu *vcpu, sigset_t *sigset)
 780 {
 781         if (sigset) {
 782                 sigdelsetmask(sigset, sigmask(SIGKILL)|sigmask(SIGSTOP));
 783                 vcpu->sigset_active = 1;
 784                 vcpu->sigset = *sigset;
 785         } else
 786                 vcpu->sigset_active = 0;
 787         return 0;
 788 }
 789
 790 static long kvm_vcpu_ioctl(struct file *filp,
 791                            unsigned int ioctl, unsigned long arg)
 792 {
 793         struct kvm_vcpu *vcpu = filp->private_data;
 794         void __user *argp = (void __user *)arg;
 795         int r;
 796
 797         if (vcpu->kvm->mm != current->mm)
 798                 return -EIO;
 799         switch (ioctl) {
 800         case KVM_RUN:
 801                 r = -EINVAL;
 802                 if (arg)
 803                         goto out;
 804                 r = kvm_arch_vcpu_ioctl_run(vcpu, vcpu->run);
 805                 break;
 806         case KVM_GET_REGS: {
 807                 struct kvm_regs kvm_regs;
 808
 809                 memset(&kvm_regs, 0, sizeof kvm_regs);
 810                 r = kvm_arch_vcpu_ioctl_get_regs(vcpu, &kvm_regs);
 811                 if (r)
 812                         goto out;
 813                 r = -EFAULT;
 814                 if (copy_to_user(argp, &kvm_regs, sizeof kvm_regs))
 815                         goto out;
 816                 r = 0;
 817                 break;
 818         }
 819         case KVM_SET_REGS: {
 820                 struct kvm_regs kvm_regs;
 821
 822                 r = -EFAULT;
 823                 if (copy_from_user(&kvm_regs, argp, sizeof kvm_regs))
 824                         goto out;
 825                 r = kvm_arch_vcpu_ioctl_set_regs(vcpu, &kvm_regs);
 826                 if (r)
 827                         goto out;
 828                 r = 0;
 829                 break;
 830         }
 831         case KVM_GET_SREGS: {
 832                 struct kvm_sregs kvm_sregs;
 833
 834                 memset(&kvm_sregs, 0, sizeof kvm_sregs);
 835                 r = kvm_arch_vcpu_ioctl_get_sregs(vcpu, &kvm_sregs);
 836                 if (r)
 837                         goto out;
 838                 r = -EFAULT;
 839                 if (copy_to_user(argp, &kvm_sregs, sizeof kvm_sregs))
 840                         goto out;
 841                 r = 0;
 842                 break;
 843         }
 844         case KVM_SET_SREGS: {
 845                 struct kvm_sregs kvm_sregs;
 846
 847                 r = -EFAULT;
 848                 if (copy_from_user(&kvm_sregs, argp, sizeof kvm_sregs))
 849                         goto out;
 850                 r = kvm_arch_vcpu_ioctl_set_sregs(vcpu, &kvm_sregs);
 851                 if (r)
 852                         goto out;
 853                 r = 0;
 854                 break;
 855         }
 856         case KVM_TRANSLATE: {
 857                 struct kvm_translation tr;
 858
 859                 r = -EFAULT;
 860                 if (copy_from_user(&tr, argp, sizeof tr))
 861                         goto out;
 862                 r = kvm_arch_vcpu_ioctl_translate(vcpu, &tr);
 863                 if (r)
 864                         goto out;
 865                 r = -EFAULT;
 866                 if (copy_to_user(argp, &tr, sizeof tr))
 867                         goto out;
 868                 r = 0;
 869                 break;
 870         }
 871         case KVM_DEBUG_GUEST: {
 872                 struct kvm_debug_guest dbg;
 873
 874                 r = -EFAULT;
 875                 if (copy_from_user(&dbg, argp, sizeof dbg))
 876                         goto out;
 877                 r = kvm_arch_vcpu_ioctl_debug_guest(vcpu, &dbg);
 878                 if (r)
 879                         goto out;
 880                 r = 0;
 881                 break;
 882         }
 883         case KVM_SET_SIGNAL_MASK: {
 884                 struct kvm_signal_mask __user *sigmask_arg = argp;
 885                 struct kvm_signal_mask kvm_sigmask;
 886                 sigset_t sigset, *p;
 887
 888                 p = NULL;
 889                 if (argp) {
 890                         r = -EFAULT;
 891                         if (copy_from_user(&kvm_sigmask, argp,
 892                                            sizeof kvm_sigmask))
 893                                 goto out;
 894                         r = -EINVAL;
 895                         if (kvm_sigmask.len != sizeof sigset)
 896                                 goto out;
 897                         r = -EFAULT;
 898                         if (copy_from_user(&sigset, sigmask_arg->sigset,
 899                                            sizeof sigset))
 900                                 goto out;
 901                         p = &sigset;
 902                 }
 903                 r = kvm_vcpu_ioctl_set_sigmask(vcpu, &sigset);
 904                 break;
 905         }
 906         case KVM_GET_FPU: {
 907                 struct kvm_fpu fpu;
 908
 909                 memset(&fpu, 0, sizeof fpu);
 910                 r = kvm_arch_vcpu_ioctl_get_fpu(vcpu, &fpu);
 911                 if (r)
 912                         goto out;
 913                 r = -EFAULT;
 914                 if (copy_to_user(argp, &fpu, sizeof fpu))
 915                         goto out;
 916                 r = 0;
 917                 break;
 918         }
 919         case KVM_SET_FPU: {
 920                 struct kvm_fpu fpu;
 921
 922                 r = -EFAULT;
 923                 if (copy_from_user(&fpu, argp, sizeof fpu))
 924                         goto out;
 925                 r = kvm_arch_vcpu_ioctl_set_fpu(vcpu, &fpu);
 926                 if (r)
 927                         goto out;
 928                 r = 0;
 929                 break;
 930         }
 931         default:
 932                 r = kvm_arch_vcpu_ioctl(filp, ioctl, arg);
 933         }
 934 out:
 935         return r;
 936 }
 937
 938 static long kvm_vm_ioctl(struct file *filp,
 939                            unsigned int ioctl, unsigned long arg)
 940 {
 941         struct kvm *kvm = filp->private_data;
 942         void __user *argp = (void __user *)arg;
 943         int r;
 944
 945         if (kvm->mm != current->mm)
 946                 return -EIO;
 947         switch (ioctl) {
 948         case KVM_CREATE_VCPU:
 949                 r = kvm_vm_ioctl_create_vcpu(kvm, arg);
 950                 if (r < 0)
 951                         goto out;
 952                 break;
 953         case KVM_SET_USER_MEMORY_REGION: {
 954                 struct kvm_userspace_memory_region kvm_userspace_mem;
 955
 956                 r = -EFAULT;
 957                 if (copy_from_user(&kvm_userspace_mem, argp,
 958                                                 sizeof kvm_userspace_mem))
 959                         goto out;
 960
 961                 r = kvm_vm_ioctl_set_memory_region(kvm, &kvm_userspace_mem, 1);
 962                 if (r)
 963                         goto out;
 964                 break;
 965         }
 966         case KVM_GET_DIRTY_LOG: {
 967                 struct kvm_dirty_log log;
 968
 969                 r = -EFAULT;
 970                 if (copy_from_user(&log, argp, sizeof log))
 971                         goto out;
 972                 r = kvm_vm_ioctl_get_dirty_log(kvm, &log);
 973                 if (r)
 974                         goto out;
 975                 break;
 976         }
 977         default:
 978                 r = kvm_arch_vm_ioctl(filp, ioctl, arg);
 979         }
 980 out:
 981         return r;
 982 }
 983
 984 static int kvm_vm_fault(struct vm_area_struct *vma, struct vm_fault *vmf)
 985 {
 986         struct kvm *kvm = vma->vm_file->private_data;
 987         struct page *page;
 988
 989         if (!kvm_is_visible_gfn(kvm, vmf->pgoff))
 990                 return VM_FAULT_SIGBUS;
 991         page = gfn_to_page(kvm, vmf->pgoff);
 992         if (is_error_page(page)) {
 993                 kvm_release_page_clean(page);
 994                 return VM_FAULT_SIGBUS;
 995         }
 996         vmf->page = page;
 997         return 0;
 998 }
 999
1000 static struct vm_operations_struct kvm_vm_vm_ops = {
1001         .fault = kvm_vm_fault,
1002 };
1003
1004 static int kvm_vm_mmap(struct file *file, struct vm_area_struct *vma)
1005 {
1006         vma->vm_ops = &kvm_vm_vm_ops;
1007         return 0;
1008 }
1009
1010 static const struct file_operations kvm_vm_fops = {
1011         .release        = kvm_vm_release,
1012         .unlocked_ioctl = kvm_vm_ioctl,
1013         .compat_ioctl   = kvm_vm_ioctl,
1014         .mmap           = kvm_vm_mmap,
1015 };
1016
1017 static int kvm_dev_ioctl_create_vm(void)
1018 {
1019         int fd, r;
1020         struct inode *inode;
1021         struct file *file;
1022         struct kvm *kvm;
1023
1024         kvm = kvm_create_vm();
1025         if (IS_ERR(kvm))
1026                 return PTR_ERR(kvm);
1027         r = anon_inode_getfd(&fd, &inode, &file, "kvm-vm", &kvm_vm_fops, kvm);
1028         if (r) {
1029                 kvm_destroy_vm(kvm);
1030                 return r;
1031         }
1032
1033         kvm->filp = file;
1034
1035         return fd;
1036 }
1037
1038 static long kvm_dev_ioctl(struct file *filp,
1039                           unsigned int ioctl, unsigned long arg)
1040 {
1041         void __user *argp = (void __user *)arg;
1042         long r = -EINVAL;
1043
1044         switch (ioctl) {
1045         case KVM_GET_API_VERSION:
1046                 r = -EINVAL;
1047                 if (arg)
1048                         goto out;
1049                 r = KVM_API_VERSION;
1050                 break;
1051         case KVM_CREATE_VM:
1052                 r = -EINVAL;
1053                 if (arg)
1054                         goto out;
1055                 r = kvm_dev_ioctl_create_vm();
1056                 break;
1057         case KVM_CHECK_EXTENSION:
1058                 r = kvm_dev_ioctl_check_extension((long)argp);
1059                 break;
1060         case KVM_GET_VCPU_MMAP_SIZE:
1061                 r = -EINVAL;
1062                 if (arg)
1063                         goto out;
1064                 r = PAGE_SIZE;     /* struct kvm_run */
1065 #ifdef CONFIG_X86
1066                 r += PAGE_SIZE;    /* pio data page */
1067 #endif
1068                 break;
1069         default:
1070                 return kvm_arch_dev_ioctl(filp, ioctl, arg);
1071         }
1072 out:
1073         return r;
1074 }
1075
1076 static struct file_operations kvm_chardev_ops = {
1077         .unlocked_ioctl = kvm_dev_ioctl,
1078         .compat_ioctl   = kvm_dev_ioctl,
1079 };
1080
1081 static struct miscdevice kvm_dev = {
1082         KVM_MINOR,
1083         "kvm",
1084         &kvm_chardev_ops,
1085 };
1086
1087 static void hardware_enable(void *junk)
1088 {
1089         int cpu = raw_smp_processor_id();
1090
1091         if (cpu_isset(cpu, cpus_hardware_enabled))
1092                 return;
1093         cpu_set(cpu, cpus_hardware_enabled);
1094         kvm_arch_hardware_enable(NULL);
1095 }
1096
1097 static void hardware_disable(void *junk)
1098 {
1099         int cpu = raw_smp_processor_id();
1100
1101         if (!cpu_isset(cpu, cpus_hardware_enabled))
1102                 return;
1103         cpu_clear(cpu, cpus_hardware_enabled);
1104         decache_vcpus_on_cpu(cpu);
1105         kvm_arch_hardware_disable(NULL);
1106 }
1107
1108 static int kvm_cpu_hotplug(struct notifier_block *notifier, unsigned long val,
1109                            void *v)
1110 {
1111         int cpu = (long)v;
1112
1113         val &= ~CPU_TASKS_FROZEN;
1114         switch (val) {
1115         case CPU_DYING:
1116                 printk(KERN_INFO "kvm: disabling virtualization on CPU%d\n",
1117                        cpu);
1118                 hardware_disable(NULL);
1119                 break;
1120         case CPU_UP_CANCELED:
1121                 printk(KERN_INFO "kvm: disabling virtualization on CPU%d\n",
1122                        cpu);
1123                 smp_call_function_single(cpu, hardware_disable, NULL, 0, 1);
1124                 break;
1125         case CPU_ONLINE:
1126                 printk(KERN_INFO "kvm: enabling virtualization on CPU%d\n",
1127                        cpu);
1128                 smp_call_function_single(cpu, hardware_enable, NULL, 0, 1);
1129                 break;
1130         }
1131         return NOTIFY_OK;
1132 }
1133
1134 static int kvm_reboot(struct notifier_block *notifier, unsigned long val,
1135                       void *v)
1136 {
1137         if (val == SYS_RESTART) {
1138                 /*
1139                  * Some (well, at least mine) BIOSes hang on reboot if
1140                  * in vmx root mode.
1141                  */
1142                 printk(KERN_INFO "kvm: exiting hardware virtualization\n");
1143                 on_each_cpu(hardware_disable, NULL, 0, 1);
1144         }
1145         return NOTIFY_OK;
1146 }
1147
1148 static struct notifier_block kvm_reboot_notifier = {
1149         .notifier_call = kvm_reboot,
1150         .priority = 0,
1151 };
1152
1153 void kvm_io_bus_init(struct kvm_io_bus *bus)
1154 {
1155         memset(bus, 0, sizeof(*bus));
1156 }
1157
1158 void kvm_io_bus_destroy(struct kvm_io_bus *bus)
1159 {
1160         int i;
1161
1162         for (i = 0; i < bus->dev_count; i++) {
1163                 struct kvm_io_device *pos = bus->devs[i];
1164
1165                 kvm_iodevice_destructor(pos);
1166         }
1167 }
1168
1169 struct kvm_io_device *kvm_io_bus_find_dev(struct kvm_io_bus *bus, gpa_t addr)
1170 {
1171         int i;
1172
1173         for (i = 0; i < bus->dev_count; i++) {
1174                 struct kvm_io_device *pos = bus->devs[i];
1175
1176                 if (pos->in_range(pos, addr))
1177                         return pos;
1178         }
1179
1180         return NULL;
1181 }
1182
1183 void kvm_io_bus_register_dev(struct kvm_io_bus *bus, struct kvm_io_device *dev)
1184 {
1185         BUG_ON(bus->dev_count > (NR_IOBUS_DEVS-1));
1186
1187         bus->devs[bus->dev_count++] = dev;
1188 }
1189
1190 static struct notifier_block kvm_cpu_notifier = {
1191         .notifier_call = kvm_cpu_hotplug,
1192         .priority = 20, /* must be > scheduler priority */
1193 };
1194
1195 static int vm_stat_get(void *_offset, u64 *val)
1196 {
1197         unsigned offset = (long)_offset;
1198         struct kvm *kvm;
1199
1200         *val = 0;
1201         spin_lock(&kvm_lock);
1202         list_for_each_entry(kvm, &vm_list, vm_list)
1203                 *val += *(u32 *)((void *)kvm + offset);
1204         spin_unlock(&kvm_lock);
1205         return 0;
1206 }
1207
1208 DEFINE_SIMPLE_ATTRIBUTE(vm_stat_fops, vm_stat_get, NULL, "%llu\n");
1209
1210 static int vcpu_stat_get(void *_offset, u64 *val)
1211 {
1212         unsigned offset = (long)_offset;
1213         struct kvm *kvm;
1214         struct kvm_vcpu *vcpu;
1215         int i;
1216
1217         *val = 0;
1218         spin_lock(&kvm_lock);
1219         list_for_each_entry(kvm, &vm_list, vm_list)
1220                 for (i = 0; i < KVM_MAX_VCPUS; ++i) {
1221                         vcpu = kvm->vcpus[i];
1222                         if (vcpu)
1223                                 *val += *(u32 *)((void *)vcpu + offset);
1224                 }
1225         spin_unlock(&kvm_lock);
1226         return 0;
1227 }
1228
1229 DEFINE_SIMPLE_ATTRIBUTE(vcpu_stat_fops, vcpu_stat_get, NULL, "%llu\n");
1230
1231 static struct file_operations *stat_fops[] = {
1232         [KVM_STAT_VCPU] = &vcpu_stat_fops,
1233         [KVM_STAT_VM]   = &vm_stat_fops,
1234 };
1235
1236 static void kvm_init_debug(void)
1237 {
1238         struct kvm_stats_debugfs_item *p;
1239
1240         debugfs_dir = debugfs_create_dir("kvm", NULL);
1241         for (p = debugfs_entries; p->name; ++p)
1242                 p->dentry = debugfs_create_file(p->name, 0444, debugfs_dir,
1243                                                 (void *)(long)p->offset,
1244                                                 stat_fops[p->kind]);
1245 }
1246
1247 static void kvm_exit_debug(void)
1248 {
1249         struct kvm_stats_debugfs_item *p;
1250
1251         for (p = debugfs_entries; p->name; ++p)
1252                 debugfs_remove(p->dentry);
1253         debugfs_remove(debugfs_dir);
1254 }
1255
1256 static int kvm_suspend(struct sys_device *dev, pm_message_t state)
1257 {
1258         hardware_disable(NULL);
1259         return 0;
1260 }
1261
1262 static int kvm_resume(struct sys_device *dev)
1263 {
1264         hardware_enable(NULL);
1265         return 0;
1266 }
1267
1268 static struct sysdev_class kvm_sysdev_class = {
1269         .name = "kvm",
1270         .suspend = kvm_suspend,
1271         .resume = kvm_resume,
1272 };
1273
1274 static struct sys_device kvm_sysdev = {
1275         .id = 0,
1276         .cls = &kvm_sysdev_class,
1277 };
1278
1279 struct page *bad_page;
1280
1281 static inline
1282 struct kvm_vcpu *preempt_notifier_to_vcpu(struct preempt_notifier *pn)
1283 {
1284         return container_of(pn, struct kvm_vcpu, preempt_notifier);
1285 }
1286
1287 static void kvm_sched_in(struct preempt_notifier *pn, int cpu)
1288 {
1289         struct kvm_vcpu *vcpu = preempt_notifier_to_vcpu(pn);
1290
1291         kvm_arch_vcpu_load(vcpu, cpu);
1292 }
1293
1294 static void kvm_sched_out(struct preempt_notifier *pn,
1295                           struct task_struct *next)
1296 {
1297         struct kvm_vcpu *vcpu = preempt_notifier_to_vcpu(pn);
1298
1299         kvm_arch_vcpu_put(vcpu);
1300 }
1301
1302 int kvm_init(void *opaque, unsigned int vcpu_size,
1303                   struct module *module)
1304 {
1305         int r;
1306         int cpu;
1307
1308         kvm_init_debug();
1309
1310         r = kvm_arch_init(opaque);
1311         if (r)
1312                 goto out_fail;
1313
1314         bad_page = alloc_page(GFP_KERNEL | __GFP_ZERO);
1315
1316         if (bad_page == NULL) {
1317                 r = -ENOMEM;
1318                 goto out;
1319         }
1320
1321         r = kvm_arch_hardware_setup();
1322         if (r < 0)
1323                 goto out_free_0;
1324
1325         for_each_online_cpu(cpu) {
1326                 smp_call_function_single(cpu,
1327                                 kvm_arch_check_processor_compat,
1328                                 &r, 0, 1);
1329                 if (r < 0)
1330                         goto out_free_1;
1331         }
1332
1333         on_each_cpu(hardware_enable, NULL, 0, 1);
1334         r = register_cpu_notifier(&kvm_cpu_notifier);
1335         if (r)
1336                 goto out_free_2;
1337         register_reboot_notifier(&kvm_reboot_notifier);
1338
1339         r = sysdev_class_register(&kvm_sysdev_class);
1340         if (r)
1341                 goto out_free_3;
1342
1343         r = sysdev_register(&kvm_sysdev);
1344         if (r)
1345                 goto out_free_4;
1346
1347         /* A kmem cache lets us meet the alignment requirements of fx_save. */
1348         kvm_vcpu_cache = kmem_cache_create("kvm_vcpu", vcpu_size,
1349                                            __alignof__(struct kvm_vcpu),
1350                                            0, NULL);
1351         if (!kvm_vcpu_cache) {
1352                 r = -ENOMEM;
1353                 goto out_free_5;
1354         }
1355
1356         kvm_chardev_ops.owner = module;
1357
1358         r = misc_register(&kvm_dev);
1359         if (r) {
1360                 printk(KERN_ERR "kvm: misc device register failed\n");
1361                 goto out_free;
1362         }
1363
1364         kvm_preempt_ops.sched_in = kvm_sched_in;
1365         kvm_preempt_ops.sched_out = kvm_sched_out;
1366
1367         return 0;
1368
1369 out_free:
1370         kmem_cache_destroy(kvm_vcpu_cache);
1371 out_free_5:
1372         sysdev_unregister(&kvm_sysdev);
1373 out_free_4:
1374         sysdev_class_unregister(&kvm_sysdev_class);
1375 out_free_3:
1376         unregister_reboot_notifier(&kvm_reboot_notifier);
1377         unregister_cpu_notifier(&kvm_cpu_notifier);
1378 out_free_2:
1379         on_each_cpu(hardware_disable, NULL, 0, 1);
1380 out_free_1:
1381         kvm_arch_hardware_unsetup();
1382 out_free_0:
1383         __free_page(bad_page);
1384 out:
1385         kvm_arch_exit();
1386         kvm_exit_debug();
1387 out_fail:
1388         return r;
1389 }
1390 EXPORT_SYMBOL_GPL(kvm_init);
1391
1392 void kvm_exit(void)
1393 {
1394         misc_deregister(&kvm_dev);
1395         kmem_cache_destroy(kvm_vcpu_cache);
1396         sysdev_unregister(&kvm_sysdev);
1397         sysdev_class_unregister(&kvm_sysdev_class);
1398         unregister_reboot_notifier(&kvm_reboot_notifier);
1399         unregister_cpu_notifier(&kvm_cpu_notifier);
1400         on_each_cpu(hardware_disable, NULL, 0, 1);
1401         kvm_arch_hardware_unsetup();
1402         kvm_arch_exit();
1403         kvm_exit_debug();
1404         __free_page(bad_page);
1405 }
1406 EXPORT_SYMBOL_GPL(kvm_exit);