提交 d7e19bd8 编写于 作者: L Linus Torvalds

Merge tag 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mst/vhost

Pull vhost cleanup and virtio bugfix
 "There's a single change here, fixing a vhost bug where vhost
  initialization fails due to used ring alignment check being too
  strict"

* tag 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mst/vhost:
  vhost: relax used address alignment
  virtio_ring: document alignment requirements
......@@ -713,9 +713,13 @@ long vhost_vring_ioctl(struct vhost_dev *d, int ioctl, void __user *argp)
r = -EFAULT;
break;
}
if ((a.avail_user_addr & (sizeof *vq->avail->ring - 1)) ||
(a.used_user_addr & (sizeof *vq->used->ring - 1)) ||
(a.log_guest_addr & (sizeof *vq->used->ring - 1))) {
/* Make sure it's safe to cast pointers to vring types. */
BUILD_BUG_ON(__alignof__ *vq->avail > VRING_AVAIL_ALIGN_SIZE);
BUILD_BUG_ON(__alignof__ *vq->used > VRING_USED_ALIGN_SIZE);
if ((a.avail_user_addr & (VRING_AVAIL_ALIGN_SIZE - 1)) ||
(a.used_user_addr & (VRING_USED_ALIGN_SIZE - 1)) ||
(a.log_guest_addr & (sizeof(u64) - 1))) {
r = -EINVAL;
break;
}
......
......@@ -101,6 +101,13 @@ struct vring {
struct vring_used *used;
};
/* Alignment requirements for vring elements.
* When using pre-virtio 1.0 layout, these fall out naturally.
*/
#define VRING_AVAIL_ALIGN_SIZE 2
#define VRING_USED_ALIGN_SIZE 4
#define VRING_DESC_ALIGN_SIZE 16
/* The standard layout for the ring is a continuous chunk of memory which looks
* like this. We assume num is a power of 2.
*
......
Markdown is supported
0% .
You are about to add 0 people to the discussion. Proceed with caution.
先完成此消息的编辑!
想要评论请 注册