KVM: Disable pagefaults during copy_from_user_inatomic()

[mv-sheeva.git] / virt / kvm / kvm_main.c

diff --git a/virt/kvm/kvm_main.c b/virt/kvm/kvm_main.c
index b2e12893e3f4d4b0f39d64ff733333171e3a0dfb..cf6df5167af62fd0f9b89b2e52f10aacab4a181f 100644 (file)
--- a/virt/kvm/kvm_main.c
+++ b/virt/kvm/kvm_main.c
@@ -554,7 +554,9 @@ int kvm_read_guest_atomic(struct kvm *kvm, gpa_t gpa, void *data,
        addr = gfn_to_hva(kvm, gfn);
        if (kvm_is_error_hva(addr))
                return -EFAULT;
+       pagefault_disable();
        r = __copy_from_user_inatomic(data, (void __user *)addr + offset, len);
+       pagefault_enable();
        if (r)
                return -EFAULT;
        return 0;
@@ -678,8 +680,10 @@ static int kvm_vcpu_fault(struct vm_area_struct *vma, struct vm_fault *vmf)
 
        if (vmf->pgoff == 0)
                page = virt_to_page(vcpu->run);
+#ifdef CONFIG_X86
        else if (vmf->pgoff == KVM_PIO_PAGE_OFFSET)
                page = virt_to_page(vcpu->arch.pio_data);
+#endif
        else
                return VM_FAULT_SIGBUS;
        get_page(page);
@@ -705,7 +709,7 @@ static int kvm_vcpu_release(struct inode *inode, struct file *filp)
        return 0;
 }
 
-static struct file_operations kvm_vcpu_fops = {
+static const struct file_operations kvm_vcpu_fops = {
        .release        = kvm_vcpu_release,
        .unlocked_ioctl = kvm_vcpu_ioctl,
        .compat_ioctl   = kvm_vcpu_ioctl,
@@ -1005,7 +1009,7 @@ static int kvm_vm_mmap(struct file *file, struct vm_area_struct *vma)
        return 0;
 }
 
-static struct file_operations kvm_vm_fops = {
+static const struct file_operations kvm_vm_fops = {
        .release        = kvm_vm_release,
        .unlocked_ioctl = kvm_vm_ioctl,
        .compat_ioctl   = kvm_vm_ioctl,
@@ -1059,7 +1063,10 @@ static long kvm_dev_ioctl(struct file *filp,
                r = -EINVAL;
                if (arg)
                        goto out;
-               r = 2 * PAGE_SIZE;
+               r = PAGE_SIZE;     /* struct kvm_run */
+#ifdef CONFIG_X86
+               r += PAGE_SIZE;    /* pio data page */
+#endif
                break;
        default:
                return kvm_arch_dev_ioctl(filp, ioctl, arg);