git.oblomov.eu Git - linux-2.6/blob - drivers/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 "kvm.h"
  19 #include "x86.h"
  20 #include "irq.h"
  21
  22 #include <linux/kvm.h>
  23 #include <linux/module.h>
  24 #include <linux/errno.h>
  25 #include <linux/percpu.h>
  26 #include <linux/gfp.h>
  27 #include <linux/mm.h>
  28 #include <linux/miscdevice.h>
  29 #include <linux/vmalloc.h>
  30 #include <linux/reboot.h>
  31 #include <linux/debugfs.h>
  32 #include <linux/highmem.h>
  33 #include <linux/file.h>
  34 #include <linux/sysdev.h>
  35 #include <linux/cpu.h>
  36 #include <linux/sched.h>
  37 #include <linux/cpumask.h>
  38 #include <linux/smp.h>
  39 #include <linux/anon_inodes.h>
  40 #include <linux/profile.h>
  41 #include <linux/kvm_para.h>
  42 #include <linux/pagemap.h>
  43 #include <linux/mman.h>
  44
  45 #include <asm/processor.h>
  46 #include <asm/io.h>
  47 #include <asm/uaccess.h>
  48 #include <asm/desc.h>
  49 #include <asm/pgtable.h>
  50
  51 MODULE_AUTHOR("Qumranet");
  52 MODULE_LICENSE("GPL");
  53
  54 DEFINE_SPINLOCK(kvm_lock);
  55 LIST_HEAD(vm_list);
  56
  57 static cpumask_t cpus_hardware_enabled;
  58
  59 struct kmem_cache *kvm_vcpu_cache;
  60 EXPORT_SYMBOL_GPL(kvm_vcpu_cache);
  61
  62 static __read_mostly struct preempt_ops kvm_preempt_ops;
  63
  64 static struct dentry *debugfs_dir;
  65
  66 static long kvm_vcpu_ioctl(struct file *file, unsigned int ioctl,
  67                            unsigned long arg);
  68
  69 static inline int valid_vcpu(int n)
  70 {
  71         return likely(n >= 0 && n < KVM_MAX_VCPUS);
  72 }
  73
  74 /*
  75  * Switches to specified vcpu, until a matching vcpu_put()
  76  */
  77 void vcpu_load(struct kvm_vcpu *vcpu)
  78 {
  79         int cpu;
  80
  81         mutex_lock(&vcpu->mutex);
  82         cpu = get_cpu();
  83         preempt_notifier_register(&vcpu->preempt_notifier);
  84         kvm_arch_vcpu_load(vcpu, cpu);
  85         put_cpu();
  86 }
  87
  88 void vcpu_put(struct kvm_vcpu *vcpu)
  89 {
  90         preempt_disable();
  91         kvm_arch_vcpu_put(vcpu);
  92         preempt_notifier_unregister(&vcpu->preempt_notifier);
  93         preempt_enable();
  94         mutex_unlock(&vcpu->mutex);
  95 }
  96
  97 static void ack_flush(void *_completed)
  98 {
  99 }
 100
 101 void kvm_flush_remote_tlbs(struct kvm *kvm)
 102 {
 103         int i, cpu;
 104         cpumask_t cpus;
 105         struct kvm_vcpu *vcpu;
 106
 107         cpus_clear(cpus);
 108         for (i = 0; i < KVM_MAX_VCPUS; ++i) {
 109                 vcpu = kvm->vcpus[i];
 110                 if (!vcpu)
 111                         continue;
 112                 if (test_and_set_bit(KVM_REQ_TLB_FLUSH, &vcpu->requests))
 113                         continue;
 114                 cpu = vcpu->cpu;
 115                 if (cpu != -1 && cpu != raw_smp_processor_id())
 116                         cpu_set(cpu, cpus);
 117         }
 118         if (cpus_empty(cpus))
 119                 return;
 120         ++kvm->stat.remote_tlb_flush;
 121         smp_call_function_mask(cpus, ack_flush, NULL, 1);
 122 }
 123
 124 int kvm_vcpu_init(struct kvm_vcpu *vcpu, struct kvm *kvm, unsigned id)
 125 {
 126         struct page *page;
 127         int r;
 128
 129         mutex_init(&vcpu->mutex);
 130         vcpu->cpu = -1;
 131         vcpu->kvm = kvm;
 132         vcpu->vcpu_id = id;
 133         init_waitqueue_head(&vcpu->wq);
 134
 135         page = alloc_page(GFP_KERNEL | __GFP_ZERO);
 136         if (!page) {
 137                 r = -ENOMEM;
 138                 goto fail;
 139         }
 140         vcpu->run = page_address(page);
 141
 142         r = kvm_arch_vcpu_init(vcpu);
 143         if (r < 0)
 144                 goto fail_free_run;
 145         return 0;
 146
 147 fail_free_run:
 148         free_page((unsigned long)vcpu->run);
 149 fail:
 150         return r;
 151 }
 152 EXPORT_SYMBOL_GPL(kvm_vcpu_init);
 153
 154 void kvm_vcpu_uninit(struct kvm_vcpu *vcpu)
 155 {
 156         kvm_arch_vcpu_uninit(vcpu);
 157         free_page((unsigned long)vcpu->run);
 158 }
 159 EXPORT_SYMBOL_GPL(kvm_vcpu_uninit);
 160
 161 static struct kvm *kvm_create_vm(void)
 162 {
 163         struct kvm *kvm = kvm_arch_create_vm();
 164
 165         if (IS_ERR(kvm))
 166                 goto out;
 167
 168         kvm->mm = current->mm;
 169         atomic_inc(&kvm->mm->mm_count);
 170         kvm_io_bus_init(&kvm->pio_bus);
 171         mutex_init(&kvm->lock);
 172         kvm_io_bus_init(&kvm->mmio_bus);
 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 kvm->lock.
 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         mutex_lock(&kvm->lock);
 344         r = __kvm_set_memory_region(kvm, mem, user_alloc);
 345         mutex_unlock(&kvm->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 static 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 struct page *gfn_to_page(struct kvm *kvm, gfn_t gfn)
 487 {
 488         struct page *page;
 489
 490         down_read(&current->mm->mmap_sem);
 491         page = __gfn_to_page(kvm, gfn);
 492         up_read(&current->mm->mmap_sem);
 493
 494         return page;
 495 }
 496
 497 EXPORT_SYMBOL_GPL(gfn_to_page);
 498
 499 void kvm_release_page_clean(struct page *page)
 500 {
 501         put_page(page);
 502 }
 503 EXPORT_SYMBOL_GPL(kvm_release_page_clean);
 504
 505 void kvm_release_page_dirty(struct page *page)
 506 {
 507         if (!PageReserved(page))
 508                 SetPageDirty(page);
 509         put_page(page);
 510 }
 511 EXPORT_SYMBOL_GPL(kvm_release_page_dirty);
 512
 513 static int next_segment(unsigned long len, int offset)
 514 {
 515         if (len > PAGE_SIZE - offset)
 516                 return PAGE_SIZE - offset;
 517         else
 518                 return len;
 519 }
 520
 521 int kvm_read_guest_page(struct kvm *kvm, gfn_t gfn, void *data, int offset,
 522                         int len)
 523 {
 524         int r;
 525         unsigned long addr;
 526
 527         addr = gfn_to_hva(kvm, gfn);
 528         if (kvm_is_error_hva(addr))
 529                 return -EFAULT;
 530         r = copy_from_user(data, (void __user *)addr + offset, len);
 531         if (r)
 532                 return -EFAULT;
 533         return 0;
 534 }
 535 EXPORT_SYMBOL_GPL(kvm_read_guest_page);
 536
 537 int kvm_read_guest(struct kvm *kvm, gpa_t gpa, void *data, unsigned long len)
 538 {
 539         gfn_t gfn = gpa >> PAGE_SHIFT;
 540         int seg;
 541         int offset = offset_in_page(gpa);
 542         int ret;
 543
 544         while ((seg = next_segment(len, offset)) != 0) {
 545                 ret = kvm_read_guest_page(kvm, gfn, data, offset, seg);
 546                 if (ret < 0)
 547                         return ret;
 548                 offset = 0;
 549                 len -= seg;
 550                 data += seg;
 551                 ++gfn;
 552         }
 553         return 0;
 554 }
 555 EXPORT_SYMBOL_GPL(kvm_read_guest);
 556
 557 int kvm_write_guest_page(struct kvm *kvm, gfn_t gfn, const void *data,
 558                          int offset, int len)
 559 {
 560         int r;
 561         unsigned long addr;
 562
 563         addr = gfn_to_hva(kvm, gfn);
 564         if (kvm_is_error_hva(addr))
 565                 return -EFAULT;
 566         r = copy_to_user((void __user *)addr + offset, data, len);
 567         if (r)
 568                 return -EFAULT;
 569         mark_page_dirty(kvm, gfn);
 570         return 0;
 571 }
 572 EXPORT_SYMBOL_GPL(kvm_write_guest_page);
 573
 574 int kvm_write_guest(struct kvm *kvm, gpa_t gpa, const void *data,
 575                     unsigned long len)
 576 {
 577         gfn_t gfn = gpa >> PAGE_SHIFT;
 578         int seg;
 579         int offset = offset_in_page(gpa);
 580         int ret;
 581
 582         while ((seg = next_segment(len, offset)) != 0) {
 583                 ret = kvm_write_guest_page(kvm, gfn, data, offset, seg);
 584                 if (ret < 0)
 585                         return ret;
 586                 offset = 0;
 587                 len -= seg;
 588                 data += seg;
 589                 ++gfn;
 590         }
 591         return 0;
 592 }
 593
 594 int kvm_clear_guest_page(struct kvm *kvm, gfn_t gfn, int offset, int len)
 595 {
 596         return kvm_write_guest_page(kvm, gfn, empty_zero_page, offset, len);
 597 }
 598 EXPORT_SYMBOL_GPL(kvm_clear_guest_page);
 599
 600 int kvm_clear_guest(struct kvm *kvm, gpa_t gpa, unsigned long len)
 601 {
 602         gfn_t gfn = gpa >> PAGE_SHIFT;
 603         int seg;
 604         int offset = offset_in_page(gpa);
 605         int ret;
 606
 607         while ((seg = next_segment(len, offset)) != 0) {
 608                 ret = kvm_clear_guest_page(kvm, gfn, offset, seg);
 609                 if (ret < 0)
 610                         return ret;
 611                 offset = 0;
 612                 len -= seg;
 613                 ++gfn;
 614         }
 615         return 0;
 616 }
 617 EXPORT_SYMBOL_GPL(kvm_clear_guest);
 618
 619 void mark_page_dirty(struct kvm *kvm, gfn_t gfn)
 620 {
 621         struct kvm_memory_slot *memslot;
 622
 623         gfn = unalias_gfn(kvm, gfn);
 624         memslot = __gfn_to_memslot(kvm, gfn);
 625         if (memslot && memslot->dirty_bitmap) {
 626                 unsigned long rel_gfn = gfn - memslot->base_gfn;
 627
 628                 /* avoid RMW */
 629                 if (!test_bit(rel_gfn, memslot->dirty_bitmap))
 630                         set_bit(rel_gfn, memslot->dirty_bitmap);
 631         }
 632 }
 633
 634 /*
 635  * The vCPU has executed a HLT instruction with in-kernel mode enabled.
 636  */
 637 void kvm_vcpu_block(struct kvm_vcpu *vcpu)
 638 {
 639         DECLARE_WAITQUEUE(wait, current);
 640
 641         add_wait_queue(&vcpu->wq, &wait);
 642
 643         /*
 644          * We will block until either an interrupt or a signal wakes us up
 645          */
 646         while (!kvm_cpu_has_interrupt(vcpu)
 647                && !signal_pending(current)
 648                && vcpu->mp_state != VCPU_MP_STATE_RUNNABLE
 649                && vcpu->mp_state != VCPU_MP_STATE_SIPI_RECEIVED) {
 650                 set_current_state(TASK_INTERRUPTIBLE);
 651                 vcpu_put(vcpu);
 652                 schedule();
 653                 vcpu_load(vcpu);
 654         }
 655
 656         __set_current_state(TASK_RUNNING);
 657         remove_wait_queue(&vcpu->wq, &wait);
 658 }
 659
 660 void kvm_resched(struct kvm_vcpu *vcpu)
 661 {
 662         if (!need_resched())
 663                 return;
 664         cond_resched();
 665 }
 666 EXPORT_SYMBOL_GPL(kvm_resched);
 667
 668 static struct page *kvm_vcpu_nopage(struct vm_area_struct *vma,
 669                                     unsigned long address,
 670                                     int *type)
 671 {
 672         struct kvm_vcpu *vcpu = vma->vm_file->private_data;
 673         unsigned long pgoff;
 674         struct page *page;
 675
 676         pgoff = ((address - vma->vm_start) >> PAGE_SHIFT) + vma->vm_pgoff;
 677         if (pgoff == 0)
 678                 page = virt_to_page(vcpu->run);
 679         else if (pgoff == KVM_PIO_PAGE_OFFSET)
 680                 page = virt_to_page(vcpu->pio_data);
 681         else
 682                 return NOPAGE_SIGBUS;
 683         get_page(page);
 684         if (type != NULL)
 685                 *type = VM_FAULT_MINOR;
 686
 687         return page;
 688 }
 689
 690 static struct vm_operations_struct kvm_vcpu_vm_ops = {
 691         .nopage = kvm_vcpu_nopage,
 692 };
 693
 694 static int kvm_vcpu_mmap(struct file *file, struct vm_area_struct *vma)
 695 {
 696         vma->vm_ops = &kvm_vcpu_vm_ops;
 697         return 0;
 698 }
 699
 700 static int kvm_vcpu_release(struct inode *inode, struct file *filp)
 701 {
 702         struct kvm_vcpu *vcpu = filp->private_data;
 703
 704         fput(vcpu->kvm->filp);
 705         return 0;
 706 }
 707
 708 static struct file_operations kvm_vcpu_fops = {
 709         .release        = kvm_vcpu_release,
 710         .unlocked_ioctl = kvm_vcpu_ioctl,
 711         .compat_ioctl   = kvm_vcpu_ioctl,
 712         .mmap           = kvm_vcpu_mmap,
 713 };
 714
 715 /*
 716  * Allocates an inode for the vcpu.
 717  */
 718 static int create_vcpu_fd(struct kvm_vcpu *vcpu)
 719 {
 720         int fd, r;
 721         struct inode *inode;
 722         struct file *file;
 723
 724         r = anon_inode_getfd(&fd, &inode, &file,
 725                              "kvm-vcpu", &kvm_vcpu_fops, vcpu);
 726         if (r)
 727                 return r;
 728         atomic_inc(&vcpu->kvm->filp->f_count);
 729         return fd;
 730 }
 731
 732 /*
 733  * Creates some virtual cpus.  Good luck creating more than one.
 734  */
 735 static int kvm_vm_ioctl_create_vcpu(struct kvm *kvm, int n)
 736 {
 737         int r;
 738         struct kvm_vcpu *vcpu;
 739
 740         if (!valid_vcpu(n))
 741                 return -EINVAL;
 742
 743         vcpu = kvm_arch_vcpu_create(kvm, n);
 744         if (IS_ERR(vcpu))
 745                 return PTR_ERR(vcpu);
 746
 747         preempt_notifier_init(&vcpu->preempt_notifier, &kvm_preempt_ops);
 748
 749         r = kvm_arch_vcpu_setup(vcpu);
 750         if (r)
 751                 goto vcpu_destroy;
 752
 753         mutex_lock(&kvm->lock);
 754         if (kvm->vcpus[n]) {
 755                 r = -EEXIST;
 756                 mutex_unlock(&kvm->lock);
 757                 goto vcpu_destroy;
 758         }
 759         kvm->vcpus[n] = vcpu;
 760         mutex_unlock(&kvm->lock);
 761
 762         /* Now it's all set up, let userspace reach it */
 763         r = create_vcpu_fd(vcpu);
 764         if (r < 0)
 765                 goto unlink;
 766         return r;
 767
 768 unlink:
 769         mutex_lock(&kvm->lock);
 770         kvm->vcpus[n] = NULL;
 771         mutex_unlock(&kvm->lock);
 772 vcpu_destroy:
 773         kvm_arch_vcpu_destroy(vcpu);
 774         return r;
 775 }
 776
 777 static int kvm_vcpu_ioctl_set_sigmask(struct kvm_vcpu *vcpu, sigset_t *sigset)
 778 {
 779         if (sigset) {
 780                 sigdelsetmask(sigset, sigmask(SIGKILL)|sigmask(SIGSTOP));
 781                 vcpu->sigset_active = 1;
 782                 vcpu->sigset = *sigset;
 783         } else
 784                 vcpu->sigset_active = 0;
 785         return 0;
 786 }
 787
 788 static long kvm_vcpu_ioctl(struct file *filp,
 789                            unsigned int ioctl, unsigned long arg)
 790 {
 791         struct kvm_vcpu *vcpu = filp->private_data;
 792         void __user *argp = (void __user *)arg;
 793         int r;
 794
 795         if (vcpu->kvm->mm != current->mm)
 796                 return -EIO;
 797         switch (ioctl) {
 798         case KVM_RUN:
 799                 r = -EINVAL;
 800                 if (arg)
 801                         goto out;
 802                 r = kvm_arch_vcpu_ioctl_run(vcpu, vcpu->run);
 803                 break;
 804         case KVM_GET_REGS: {
 805                 struct kvm_regs kvm_regs;
 806
 807                 memset(&kvm_regs, 0, sizeof kvm_regs);
 808                 r = kvm_arch_vcpu_ioctl_get_regs(vcpu, &kvm_regs);
 809                 if (r)
 810                         goto out;
 811                 r = -EFAULT;
 812                 if (copy_to_user(argp, &kvm_regs, sizeof kvm_regs))
 813                         goto out;
 814                 r = 0;
 815                 break;
 816         }
 817         case KVM_SET_REGS: {
 818                 struct kvm_regs kvm_regs;
 819
 820                 r = -EFAULT;
 821                 if (copy_from_user(&kvm_regs, argp, sizeof kvm_regs))
 822                         goto out;
 823                 r = kvm_arch_vcpu_ioctl_set_regs(vcpu, &kvm_regs);
 824                 if (r)
 825                         goto out;
 826                 r = 0;
 827                 break;
 828         }
 829         case KVM_GET_SREGS: {
 830                 struct kvm_sregs kvm_sregs;
 831
 832                 memset(&kvm_sregs, 0, sizeof kvm_sregs);
 833                 r = kvm_arch_vcpu_ioctl_get_sregs(vcpu, &kvm_sregs);
 834                 if (r)
 835                         goto out;
 836                 r = -EFAULT;
 837                 if (copy_to_user(argp, &kvm_sregs, sizeof kvm_sregs))
 838                         goto out;
 839                 r = 0;
 840                 break;
 841         }
 842         case KVM_SET_SREGS: {
 843                 struct kvm_sregs kvm_sregs;
 844
 845                 r = -EFAULT;
 846                 if (copy_from_user(&kvm_sregs, argp, sizeof kvm_sregs))
 847                         goto out;
 848                 r = kvm_arch_vcpu_ioctl_set_sregs(vcpu, &kvm_sregs);
 849                 if (r)
 850                         goto out;
 851                 r = 0;
 852                 break;
 853         }
 854         case KVM_TRANSLATE: {
 855                 struct kvm_translation tr;
 856
 857                 r = -EFAULT;
 858                 if (copy_from_user(&tr, argp, sizeof tr))
 859                         goto out;
 860                 r = kvm_arch_vcpu_ioctl_translate(vcpu, &tr);
 861                 if (r)
 862                         goto out;
 863                 r = -EFAULT;
 864                 if (copy_to_user(argp, &tr, sizeof tr))
 865                         goto out;
 866                 r = 0;
 867                 break;
 868         }
 869         case KVM_DEBUG_GUEST: {
 870                 struct kvm_debug_guest dbg;
 871
 872                 r = -EFAULT;
 873                 if (copy_from_user(&dbg, argp, sizeof dbg))
 874                         goto out;
 875                 r = kvm_arch_vcpu_ioctl_debug_guest(vcpu, &dbg);
 876                 if (r)
 877                         goto out;
 878                 r = 0;
 879                 break;
 880         }
 881         case KVM_SET_SIGNAL_MASK: {
 882                 struct kvm_signal_mask __user *sigmask_arg = argp;
 883                 struct kvm_signal_mask kvm_sigmask;
 884                 sigset_t sigset, *p;
 885
 886                 p = NULL;
 887                 if (argp) {
 888                         r = -EFAULT;
 889                         if (copy_from_user(&kvm_sigmask, argp,
 890                                            sizeof kvm_sigmask))
 891                                 goto out;
 892                         r = -EINVAL;
 893                         if (kvm_sigmask.len != sizeof sigset)
 894                                 goto out;
 895                         r = -EFAULT;
 896                         if (copy_from_user(&sigset, sigmask_arg->sigset,
 897                                            sizeof sigset))
 898                                 goto out;
 899                         p = &sigset;
 900                 }
 901                 r = kvm_vcpu_ioctl_set_sigmask(vcpu, &sigset);
 902                 break;
 903         }
 904         case KVM_GET_FPU: {
 905                 struct kvm_fpu fpu;
 906
 907                 memset(&fpu, 0, sizeof fpu);
 908                 r = kvm_arch_vcpu_ioctl_get_fpu(vcpu, &fpu);
 909                 if (r)
 910                         goto out;
 911                 r = -EFAULT;
 912                 if (copy_to_user(argp, &fpu, sizeof fpu))
 913                         goto out;
 914                 r = 0;
 915                 break;
 916         }
 917         case KVM_SET_FPU: {
 918                 struct kvm_fpu fpu;
 919
 920                 r = -EFAULT;
 921                 if (copy_from_user(&fpu, argp, sizeof fpu))
 922                         goto out;
 923                 r = kvm_arch_vcpu_ioctl_set_fpu(vcpu, &fpu);
 924                 if (r)
 925                         goto out;
 926                 r = 0;
 927                 break;
 928         }
 929         default:
 930                 r = kvm_arch_vcpu_ioctl(filp, ioctl, arg);
 931         }
 932 out:
 933         return r;
 934 }
 935
 936 static long kvm_vm_ioctl(struct file *filp,
 937                            unsigned int ioctl, unsigned long arg)
 938 {
 939         struct kvm *kvm = filp->private_data;
 940         void __user *argp = (void __user *)arg;
 941         int r;
 942
 943         if (kvm->mm != current->mm)
 944                 return -EIO;
 945         switch (ioctl) {
 946         case KVM_CREATE_VCPU:
 947                 r = kvm_vm_ioctl_create_vcpu(kvm, arg);
 948                 if (r < 0)
 949                         goto out;
 950                 break;
 951         case KVM_SET_USER_MEMORY_REGION: {
 952                 struct kvm_userspace_memory_region kvm_userspace_mem;
 953
 954                 r = -EFAULT;
 955                 if (copy_from_user(&kvm_userspace_mem, argp,
 956                                                 sizeof kvm_userspace_mem))
 957                         goto out;
 958
 959                 r = kvm_vm_ioctl_set_memory_region(kvm, &kvm_userspace_mem, 1);
 960                 if (r)
 961                         goto out;
 962                 break;
 963         }
 964         case KVM_GET_DIRTY_LOG: {
 965                 struct kvm_dirty_log log;
 966
 967                 r = -EFAULT;
 968                 if (copy_from_user(&log, argp, sizeof log))
 969                         goto out;
 970                 r = kvm_vm_ioctl_get_dirty_log(kvm, &log);
 971                 if (r)
 972                         goto out;
 973                 break;
 974         }
 975         default:
 976                 r = kvm_arch_vm_ioctl(filp, ioctl, arg);
 977         }
 978 out:
 979         return r;
 980 }
 981
 982 static struct page *kvm_vm_nopage(struct vm_area_struct *vma,
 983                                   unsigned long address,
 984                                   int *type)
 985 {
 986         struct kvm *kvm = vma->vm_file->private_data;
 987         unsigned long pgoff;
 988         struct page *page;
 989
 990         pgoff = ((address - vma->vm_start) >> PAGE_SHIFT) + vma->vm_pgoff;
 991         if (!kvm_is_visible_gfn(kvm, pgoff))
 992                 return NOPAGE_SIGBUS;
 993         /* current->mm->mmap_sem is already held so call lockless version */
 994         page = __gfn_to_page(kvm, pgoff);
 995         if (is_error_page(page)) {
 996                 kvm_release_page_clean(page);
 997                 return NOPAGE_SIGBUS;
 998         }
 999         if (type != NULL)
1000                 *type = VM_FAULT_MINOR;
1001
1002         return page;
1003 }
1004
1005 static struct vm_operations_struct kvm_vm_vm_ops = {
1006         .nopage = kvm_vm_nopage,
1007 };
1008
1009 static int kvm_vm_mmap(struct file *file, struct vm_area_struct *vma)
1010 {
1011         vma->vm_ops = &kvm_vm_vm_ops;
1012         return 0;
1013 }
1014
1015 static struct file_operations kvm_vm_fops = {
1016         .release        = kvm_vm_release,
1017         .unlocked_ioctl = kvm_vm_ioctl,
1018         .compat_ioctl   = kvm_vm_ioctl,
1019         .mmap           = kvm_vm_mmap,
1020 };
1021
1022 static int kvm_dev_ioctl_create_vm(void)
1023 {
1024         int fd, r;
1025         struct inode *inode;
1026         struct file *file;
1027         struct kvm *kvm;
1028
1029         kvm = kvm_create_vm();
1030         if (IS_ERR(kvm))
1031                 return PTR_ERR(kvm);
1032         r = anon_inode_getfd(&fd, &inode, &file, "kvm-vm", &kvm_vm_fops, kvm);
1033         if (r) {
1034                 kvm_destroy_vm(kvm);
1035                 return r;
1036         }
1037
1038         kvm->filp = file;
1039
1040         return fd;
1041 }
1042
1043 static long kvm_dev_ioctl(struct file *filp,
1044                           unsigned int ioctl, unsigned long arg)
1045 {
1046         void __user *argp = (void __user *)arg;
1047         long r = -EINVAL;
1048
1049         switch (ioctl) {
1050         case KVM_GET_API_VERSION:
1051                 r = -EINVAL;
1052                 if (arg)
1053                         goto out;
1054                 r = KVM_API_VERSION;
1055                 break;
1056         case KVM_CREATE_VM:
1057                 r = -EINVAL;
1058                 if (arg)
1059                         goto out;
1060                 r = kvm_dev_ioctl_create_vm();
1061                 break;
1062         case KVM_CHECK_EXTENSION:
1063                 r = kvm_dev_ioctl_check_extension((long)argp);
1064                 break;
1065         case KVM_GET_VCPU_MMAP_SIZE:
1066                 r = -EINVAL;
1067                 if (arg)
1068                         goto out;
1069                 r = 2 * PAGE_SIZE;
1070                 break;
1071         default:
1072                 return kvm_arch_dev_ioctl(filp, ioctl, arg);
1073         }
1074 out:
1075         return r;
1076 }
1077
1078 static struct file_operations kvm_chardev_ops = {
1079         .unlocked_ioctl = kvm_dev_ioctl,
1080         .compat_ioctl   = kvm_dev_ioctl,
1081 };
1082
1083 static struct miscdevice kvm_dev = {
1084         KVM_MINOR,
1085         "kvm",
1086         &kvm_chardev_ops,
1087 };
1088
1089 static void hardware_enable(void *junk)
1090 {
1091         int cpu = raw_smp_processor_id();
1092
1093         if (cpu_isset(cpu, cpus_hardware_enabled))
1094                 return;
1095         cpu_set(cpu, cpus_hardware_enabled);
1096         kvm_arch_hardware_enable(NULL);
1097 }
1098
1099 static void hardware_disable(void *junk)
1100 {
1101         int cpu = raw_smp_processor_id();
1102
1103         if (!cpu_isset(cpu, cpus_hardware_enabled))
1104                 return;
1105         cpu_clear(cpu, cpus_hardware_enabled);
1106         decache_vcpus_on_cpu(cpu);
1107         kvm_arch_hardware_disable(NULL);
1108 }
1109
1110 static int kvm_cpu_hotplug(struct notifier_block *notifier, unsigned long val,
1111                            void *v)
1112 {
1113         int cpu = (long)v;
1114
1115         val &= ~CPU_TASKS_FROZEN;
1116         switch (val) {
1117         case CPU_DYING:
1118                 printk(KERN_INFO "kvm: disabling virtualization on CPU%d\n",
1119                        cpu);
1120                 hardware_disable(NULL);
1121                 break;
1122         case CPU_UP_CANCELED:
1123                 printk(KERN_INFO "kvm: disabling virtualization on CPU%d\n",
1124                        cpu);
1125                 smp_call_function_single(cpu, hardware_disable, NULL, 0, 1);
1126                 break;
1127         case CPU_ONLINE:
1128                 printk(KERN_INFO "kvm: enabling virtualization on CPU%d\n",
1129                        cpu);
1130                 smp_call_function_single(cpu, hardware_enable, NULL, 0, 1);
1131                 break;
1132         }
1133         return NOTIFY_OK;
1134 }
1135
1136 static int kvm_reboot(struct notifier_block *notifier, unsigned long val,
1137                       void *v)
1138 {
1139         if (val == SYS_RESTART) {
1140                 /*
1141                  * Some (well, at least mine) BIOSes hang on reboot if
1142                  * in vmx root mode.
1143                  */
1144                 printk(KERN_INFO "kvm: exiting hardware virtualization\n");
1145                 on_each_cpu(hardware_disable, NULL, 0, 1);
1146         }
1147         return NOTIFY_OK;
1148 }
1149
1150 static struct notifier_block kvm_reboot_notifier = {
1151         .notifier_call = kvm_reboot,
1152         .priority = 0,
1153 };
1154
1155 void kvm_io_bus_init(struct kvm_io_bus *bus)
1156 {
1157         memset(bus, 0, sizeof(*bus));
1158 }
1159
1160 void kvm_io_bus_destroy(struct kvm_io_bus *bus)
1161 {
1162         int i;
1163
1164         for (i = 0; i < bus->dev_count; i++) {
1165                 struct kvm_io_device *pos = bus->devs[i];
1166
1167                 kvm_iodevice_destructor(pos);
1168         }
1169 }
1170
1171 struct kvm_io_device *kvm_io_bus_find_dev(struct kvm_io_bus *bus, gpa_t addr)
1172 {
1173         int i;
1174
1175         for (i = 0; i < bus->dev_count; i++) {
1176                 struct kvm_io_device *pos = bus->devs[i];
1177
1178                 if (pos->in_range(pos, addr))
1179                         return pos;
1180         }
1181
1182         return NULL;
1183 }
1184
1185 void kvm_io_bus_register_dev(struct kvm_io_bus *bus, struct kvm_io_device *dev)
1186 {
1187         BUG_ON(bus->dev_count > (NR_IOBUS_DEVS-1));
1188
1189         bus->devs[bus->dev_count++] = dev;
1190 }
1191
1192 static struct notifier_block kvm_cpu_notifier = {
1193         .notifier_call = kvm_cpu_hotplug,
1194         .priority = 20, /* must be > scheduler priority */
1195 };
1196
1197 static u64 vm_stat_get(void *_offset)
1198 {
1199         unsigned offset = (long)_offset;
1200         u64 total = 0;
1201         struct kvm *kvm;
1202
1203         spin_lock(&kvm_lock);
1204         list_for_each_entry(kvm, &vm_list, vm_list)
1205                 total += *(u32 *)((void *)kvm + offset);
1206         spin_unlock(&kvm_lock);
1207         return total;
1208 }
1209
1210 DEFINE_SIMPLE_ATTRIBUTE(vm_stat_fops, vm_stat_get, NULL, "%llu\n");
1211
1212 static u64 vcpu_stat_get(void *_offset)
1213 {
1214         unsigned offset = (long)_offset;
1215         u64 total = 0;
1216         struct kvm *kvm;
1217         struct kvm_vcpu *vcpu;
1218         int i;
1219
1220         spin_lock(&kvm_lock);
1221         list_for_each_entry(kvm, &vm_list, vm_list)
1222                 for (i = 0; i < KVM_MAX_VCPUS; ++i) {
1223                         vcpu = kvm->vcpus[i];
1224                         if (vcpu)
1225                                 total += *(u32 *)((void *)vcpu + offset);
1226                 }
1227         spin_unlock(&kvm_lock);
1228         return total;
1229 }
1230
1231 DEFINE_SIMPLE_ATTRIBUTE(vcpu_stat_fops, vcpu_stat_get, NULL, "%llu\n");
1232
1233 static struct file_operations *stat_fops[] = {
1234         [KVM_STAT_VCPU] = &vcpu_stat_fops,
1235         [KVM_STAT_VM]   = &vm_stat_fops,
1236 };
1237
1238 static void kvm_init_debug(void)
1239 {
1240         struct kvm_stats_debugfs_item *p;
1241
1242         debugfs_dir = debugfs_create_dir("kvm", NULL);
1243         for (p = debugfs_entries; p->name; ++p)
1244                 p->dentry = debugfs_create_file(p->name, 0444, debugfs_dir,
1245                                                 (void *)(long)p->offset,
1246                                                 stat_fops[p->kind]);
1247 }
1248
1249 static void kvm_exit_debug(void)
1250 {
1251         struct kvm_stats_debugfs_item *p;
1252
1253         for (p = debugfs_entries; p->name; ++p)
1254                 debugfs_remove(p->dentry);
1255         debugfs_remove(debugfs_dir);
1256 }
1257
1258 static int kvm_suspend(struct sys_device *dev, pm_message_t state)
1259 {
1260         hardware_disable(NULL);
1261         return 0;
1262 }
1263
1264 static int kvm_resume(struct sys_device *dev)
1265 {
1266         hardware_enable(NULL);
1267         return 0;
1268 }
1269
1270 static struct sysdev_class kvm_sysdev_class = {
1271         .name = "kvm",
1272         .suspend = kvm_suspend,
1273         .resume = kvm_resume,
1274 };
1275
1276 static struct sys_device kvm_sysdev = {
1277         .id = 0,
1278         .cls = &kvm_sysdev_class,
1279 };
1280
1281 struct page *bad_page;
1282
1283 static inline
1284 struct kvm_vcpu *preempt_notifier_to_vcpu(struct preempt_notifier *pn)
1285 {
1286         return container_of(pn, struct kvm_vcpu, preempt_notifier);
1287 }
1288
1289 static void kvm_sched_in(struct preempt_notifier *pn, int cpu)
1290 {
1291         struct kvm_vcpu *vcpu = preempt_notifier_to_vcpu(pn);
1292
1293         kvm_arch_vcpu_load(vcpu, cpu);
1294 }
1295
1296 static void kvm_sched_out(struct preempt_notifier *pn,
1297                           struct task_struct *next)
1298 {
1299         struct kvm_vcpu *vcpu = preempt_notifier_to_vcpu(pn);
1300
1301         kvm_arch_vcpu_put(vcpu);
1302 }
1303
1304 int kvm_init(void *opaque, unsigned int vcpu_size,
1305                   struct module *module)
1306 {
1307         int r;
1308         int cpu;
1309
1310         kvm_init_debug();
1311
1312         r = kvm_arch_init(opaque);
1313         if (r)
1314                 goto out_fail;
1315
1316         bad_page = alloc_page(GFP_KERNEL | __GFP_ZERO);
1317
1318         if (bad_page == NULL) {
1319                 r = -ENOMEM;
1320                 goto out;
1321         }
1322
1323         r = kvm_arch_hardware_setup();
1324         if (r < 0)
1325                 goto out_free_0;
1326
1327         for_each_online_cpu(cpu) {
1328                 smp_call_function_single(cpu,
1329                                 kvm_arch_check_processor_compat,
1330                                 &r, 0, 1);
1331                 if (r < 0)
1332                         goto out_free_1;
1333         }
1334
1335         on_each_cpu(hardware_enable, NULL, 0, 1);
1336         r = register_cpu_notifier(&kvm_cpu_notifier);
1337         if (r)
1338                 goto out_free_2;
1339         register_reboot_notifier(&kvm_reboot_notifier);
1340
1341         r = sysdev_class_register(&kvm_sysdev_class);
1342         if (r)
1343                 goto out_free_3;
1344
1345         r = sysdev_register(&kvm_sysdev);
1346         if (r)
1347                 goto out_free_4;
1348
1349         /* A kmem cache lets us meet the alignment requirements of fx_save. */
1350         kvm_vcpu_cache = kmem_cache_create("kvm_vcpu", vcpu_size,
1351                                            __alignof__(struct kvm_vcpu),
1352                                            0, NULL);
1353         if (!kvm_vcpu_cache) {
1354                 r = -ENOMEM;
1355                 goto out_free_5;
1356         }
1357
1358         kvm_chardev_ops.owner = module;
1359
1360         r = misc_register(&kvm_dev);
1361         if (r) {
1362                 printk(KERN_ERR "kvm: misc device register failed\n");
1363                 goto out_free;
1364         }
1365
1366         kvm_preempt_ops.sched_in = kvm_sched_in;
1367         kvm_preempt_ops.sched_out = kvm_sched_out;
1368
1369         return 0;
1370
1371 out_free:
1372         kmem_cache_destroy(kvm_vcpu_cache);
1373 out_free_5:
1374         sysdev_unregister(&kvm_sysdev);
1375 out_free_4:
1376         sysdev_class_unregister(&kvm_sysdev_class);
1377 out_free_3:
1378         unregister_reboot_notifier(&kvm_reboot_notifier);
1379         unregister_cpu_notifier(&kvm_cpu_notifier);
1380 out_free_2:
1381         on_each_cpu(hardware_disable, NULL, 0, 1);
1382 out_free_1:
1383         kvm_arch_hardware_unsetup();
1384 out_free_0:
1385         __free_page(bad_page);
1386 out:
1387         kvm_arch_exit();
1388         kvm_exit_debug();
1389 out_fail:
1390         return r;
1391 }
1392 EXPORT_SYMBOL_GPL(kvm_init);
1393
1394 void kvm_exit(void)
1395 {
1396         misc_deregister(&kvm_dev);
1397         kmem_cache_destroy(kvm_vcpu_cache);
1398         sysdev_unregister(&kvm_sysdev);
1399         sysdev_class_unregister(&kvm_sysdev_class);
1400         unregister_reboot_notifier(&kvm_reboot_notifier);
1401         unregister_cpu_notifier(&kvm_cpu_notifier);
1402         on_each_cpu(hardware_disable, NULL, 0, 1);
1403         kvm_arch_hardware_unsetup();
1404         kvm_arch_exit();
1405         kvm_exit_debug();
1406         __free_page(bad_page);
1407 }
1408 EXPORT_SYMBOL_GPL(kvm_exit);