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Subject: Re: [PROBLEM] nbd requests become stuck when devices watched by
 inotify emit udev uevent changes
To:     Josef Bacik <josef@toxicpanda.com>
CC:     Matthew Ruffell <matthew.ruffell@canonical.com>,
        Jens Axboe <axboe@kernel.dk>,
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From:   "yukuai (C)" <yukuai3@huawei.com>
Message-ID: <e0718adf-fe2a-5f1d-a880-bac72cabfe42@huawei.com>
Date:   Mon, 16 May 2022 20:53:21 +0800
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在 2022/05/16 20:17, Josef Bacik 写道:

>> Hi, Josef
>>
>> This seems to try to fix the same problem that I described here:
>>
>> nbd: fix io hung while disconnecting device
>> https://lists.debian.org/nbd/2022/04/msg00207.html
>>
>> There are still some io that are stuck, which means the devcie is
>> probably still opened. Thus nbd_config_put() can't reach here.
>> I'm afraid this patch can't fix the io hung.
>>
>> Matthew, can you try a test with this patch together with my patch below
>> to comfirm my thought?
>>
>> nbd: don't clear 'NBD_CMD_INFLIGHT' flag if request is not completed
>> https://lists.debian.org/nbd/2022/04/msg00212.html.
>>
> 
> Re-submit this one, but fix it so we just test the bit to see if we need to skip
> it, and change it so we only CLEAR when we're sure we're going to complete the
> request.  Thanks,

Ok, thanks for your advice. I'll send a new version.

BTW, do you have any suggestions on other patches of the patchset?

https://lore.kernel.org/all/20220426130746.885140-1-yukuai3@huawei.com/

Thanks,
Kuai
> 
> Josef
> .
>