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Date:   Mon, 12 Jul 2021 07:27:40 +0200
From:   Christoph Hellwig <hch@lst.de>
To:     Hillf Danton <hdanton@sina.com>
Cc:     syzbot <syzbot+118992efda475c16dfb0@syzkaller.appspotmail.com>,
        axboe@kernel.dk, hch@lst.de, linux-block@vger.kernel.org,
        linux-kernel@vger.kernel.org, syzkaller-bugs@googlegroups.com,
        Desmond Cheong Zhi Xi <desmondcheongzx@gmail.com>
Subject: Re: [syzbot] possible deadlock in loop_add
Message-ID: <20210712052740.GA8599@lst.de>
References: <000000000000ec01e405c6c2cee3@google.com> <20210710131638.605-1-hdanton@sina.com>
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On Sat, Jul 10, 2021 at 09:16:38PM +0800, Hillf Danton wrote:
> To break the lock chain, un/register blkdev without mtd_table_mutex held.

Yes, Desmond Cheong Zhi Xi sent pretty much the same patch on June 18th
(mtd: break circular locks in register_mtd_blktrans), but it did not get
picked up.