diff options
Diffstat (limited to 'virt/kvm/kvm_main.c')
| -rw-r--r-- | virt/kvm/kvm_main.c | 49 |
1 files changed, 27 insertions, 22 deletions
diff --git a/virt/kvm/kvm_main.c b/virt/kvm/kvm_main.c index 556e3efe5325..22cdb960660a 100644 --- a/virt/kvm/kvm_main.c +++ b/virt/kvm/kvm_main.c @@ -467,6 +467,7 @@ static struct kvm *kvm_create_vm(void) if (!kvm->buses[i]) goto out_err; } + spin_lock_init(&kvm->mmu_lock); r = kvm_init_mmu_notifier(kvm); if (r) @@ -474,7 +475,6 @@ static struct kvm *kvm_create_vm(void) kvm->mm = current->mm; atomic_inc(&kvm->mm->mm_count); - spin_lock_init(&kvm->mmu_lock); kvm_eventfd_init(kvm); mutex_init(&kvm->lock); mutex_init(&kvm->irq_lock); @@ -648,7 +648,10 @@ int __kvm_set_memory_region(struct kvm *kvm, goto out; if (mem->guest_phys_addr & (PAGE_SIZE - 1)) goto out; - if (user_alloc && (mem->userspace_addr & (PAGE_SIZE - 1))) + /* We can read the guest memory with __xxx_user() later on. */ + if (user_alloc && + ((mem->userspace_addr & (PAGE_SIZE - 1)) || + !access_ok(VERIFY_WRITE, mem->userspace_addr, mem->memory_size))) goto out; if (mem->slot >= KVM_MEMORY_SLOTS + KVM_PRIVATE_MEM_SLOTS) goto out; @@ -996,23 +999,6 @@ out: return size; } -int memslot_id(struct kvm *kvm, gfn_t gfn) -{ - int i; - struct kvm_memslots *slots = kvm_memslots(kvm); - struct kvm_memory_slot *memslot = NULL; - - for (i = 0; i < slots->nmemslots; ++i) { - memslot = &slots->memslots[i]; - - if (gfn >= memslot->base_gfn - && gfn < memslot->base_gfn + memslot->npages) - break; - } - - return memslot - slots->memslots; -} - static unsigned long gfn_to_hva_many(struct kvm_memory_slot *slot, gfn_t gfn, gfn_t *nr_pages) { @@ -1037,6 +1023,17 @@ static pfn_t get_fault_pfn(void) return fault_pfn; } +int get_user_page_nowait(struct task_struct *tsk, struct mm_struct *mm, + unsigned long start, int write, struct page **page) +{ + int flags = FOLL_TOUCH | FOLL_NOWAIT | FOLL_HWPOISON | FOLL_GET; + + if (write) + flags |= FOLL_WRITE; + + return __get_user_pages(tsk, mm, start, 1, flags, page, NULL, NULL); +} + static inline int check_user_page_hwpoison(unsigned long addr) { int rc, flags = FOLL_TOUCH | FOLL_HWPOISON | FOLL_WRITE; @@ -1070,7 +1067,14 @@ static pfn_t hva_to_pfn(struct kvm *kvm, unsigned long addr, bool atomic, if (writable) *writable = write_fault; - npages = get_user_pages_fast(addr, 1, write_fault, page); + if (async) { + down_read(¤t->mm->mmap_sem); + npages = get_user_page_nowait(current, current->mm, + addr, write_fault, page); + up_read(¤t->mm->mmap_sem); + } else + npages = get_user_pages_fast(addr, 1, write_fault, + page); /* map read fault as writable if possible */ if (unlikely(!write_fault) && npages == 1) { @@ -1093,7 +1097,8 @@ static pfn_t hva_to_pfn(struct kvm *kvm, unsigned long addr, bool atomic, return get_fault_pfn(); down_read(¤t->mm->mmap_sem); - if (check_user_page_hwpoison(addr)) { + if (npages == -EHWPOISON || + (!async && check_user_page_hwpoison(addr))) { up_read(¤t->mm->mmap_sem); get_page(hwpoison_page); return page_to_pfn(hwpoison_page); @@ -1281,7 +1286,7 @@ int kvm_read_guest_page(struct kvm *kvm, gfn_t gfn, void *data, int offset, addr = gfn_to_hva(kvm, gfn); if (kvm_is_error_hva(addr)) return -EFAULT; - r = copy_from_user(data, (void __user *)addr + offset, len); + r = __copy_from_user(data, (void __user *)addr + offset, len); if (r) return -EFAULT; return 0; |