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Date:   Mon, 23 Oct 2023 10:51:59 +0800
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Subject: Re: [PATCH] virtio_ring: add an error code check in virtqueue_resize
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To:     Xuan Zhuo <xuanzhuo@linux.alibaba.com>,
        "Michael S. Tsirkin" <mst@redhat.com>
Cc:     kernel-janitors@vger.kernel.org, linux-kernel@vger.kernel.org,
        virtualization@lists.linux-foundation.org
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From:   Su Hui <suhui@nfschina.com>
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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) {
+               vq->broken = true;
+               WARN_ON(err_reset);
+               return err;
+       }
+
+       return err_reset;
  }

Thanks.
Su Hui