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Subject: Re: [PATCH v3] block/loop: Serialize ioctl operations.
From:   Tetsuo Handa <penguin-kernel@i-love.sakura.ne.jp>
To:     Jens Axboe <axboe@kernel.dk>
Cc:     linux-block@vger.kernel.org, linux-kernel@vger.kernel.org,
        syzbot 
        <syzbot+4684a000d5abdade83fac55b1e7d1f935ef1936e@syzkaller.appspotmail.com>,
        syzbot <syzbot+bf89c128e05dd6c62523@syzkaller.appspotmail.com>
References: <1527297408-4428-1-git-send-email-penguin-kernel@I-love.SAKURA.ne.jp>
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 <748bce03-afda-4ed2-13b3-1fcd01d57770@kernel.dk>
 <9a9209af-c841-6034-4b4f-46d93aa0c037@i-love.sakura.ne.jp>
Message-ID: <92bffcc8-c25d-2297-80b3-24ba99075cd6@i-love.sakura.ne.jp>
Date:   Wed, 11 Jul 2018 23:29:35 +0900
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Since syzbot restarted testing linux-next.git , it is a good chance
to test this patch for unexpected regressions (until you come up with
a good alternative).

On 2018/06/26 23:34, Tetsuo Handa wrote:
> Did you get any idea?
> 
> On 2018/06/05 3:13, Jens Axboe wrote:
>> On 6/4/18 5:19 AM, Tetsuo Handa wrote:
>>> This problem was already ignored for 8 months. Unless we boost priority,
>>> this problem will be ignored for years. Jens, can we test this patch?
>>
>> Sorry, it's just that I _really_ hate this patch. We're making up
>> a weird locking primitive that tracks the process, with a weird
>> unlock helper that only unlocks if it's the process that is
>> holding the mutex.
>>
>> I'll try and think about this a bit, it would be nice if we had
>> a better alternative than the above.
>>