Re: [PATCH] virtio_ring: add an error code check in virtqueue_resize

Su Hui <suhui@xxxxxxxxxxxx> · Mon, 23 Oct 2023 11:06:48 +0800





On 2023/10/23 10:53, Xuan Zhuo wrote:
On Mon, 23 Oct 2023 10:51:59 +0800, Su Hui <suhui@xxxxxxxxxxxx> wrote:
On 2023/10/23 10:26, Xuan Zhuo wrote:
Well, what are the cases where it can happen practically?
Device error. Such as vp_active_vq()

Thanks.
Hmm interesting. OK. But do callers know to recover?
No.

So I think WARN + broken is suitable.

Thanks.
Sorry for the late, is the following code okay?

@@ -2739,7 +2739,7 @@ int virtqueue_resize(struct virtqueue *_vq, u32 num,
                       void (*recycle)(struct virtqueue *vq, void *buf))
   {
          struct vring_virtqueue *vq = to_vvq(_vq);
-       int err;
+       int err, err_reset;

          if (num > vq->vq.num_max)
                  return -E2BIG;
@@ -2759,7 +2759,15 @@ int virtqueue_resize(struct virtqueue *_vq, u32 num,
          else
                  err = virtqueue_resize_split(_vq, num);

-       return virtqueue_enable_after_reset(_vq);
+       err_reset = virtqueue_enable_after_reset(_vq);
+
+       if (err) {
No err.

err is not important.
You can remove that.

Emm, I'm a little confused that which code should I remove ?

Thanks.


+               vq->broken = true;
+               WARN_ON(err_reset);
+               return err;
+       }
+
+       return err_reset;
   }

Thanks.
Su Hui







