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Message-ID: <46aee820-6c01-ed8a-613b-5c57258d749e@nfschina.com>
Date:   Mon, 23 Oct 2023 11:06:48 +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>
Cc:     kernel-janitors@vger.kernel.org, linux-kernel@vger.kernel.org,
        virtualization@lists.linux-foundation.org,
        "Michael S. Tsirkin" <mst@redhat.com>
From:   Su Hui <suhui@nfschina.com>
In-Reply-To: <1698029596.5404413-3-xuanzhuo@linux.alibaba.com>
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On 2023/10/23 10:53, Xuan Zhuo wrote:
> On Mon, 23 Oct 2023 10:51:59 +0800, Su Hui <suhui@nfschina.com> 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
>>