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

Pull virtio fix from Michael Tsirkin:
 "A last minute regression fix.

  I thought we did a lot of testing, but a regression still managed to
  sneak in. The fix seems trivial"

* tag 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mst/vhost:
  vhost: allow batching hint without size

drivers/vhost/vhost.c

@@ -1170,7 +1170,9 @@ ssize_t vhost_chr_write_iter(struct vhost_dev *dev,
 		goto done;
 	}
 
-	if (msg.size == 0) {
+	if ((msg.type == VHOST_IOTLB_UPDATE ||
+	     msg.type == VHOST_IOTLB_INVALIDATE) &&
+	     msg.size == 0) {
 		ret = -EINVAL;
 		goto done;
 	}