From mboxrd@z Thu Jan  1 00:00:00 1970
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Subject: Re: INFO: rcu detected stall in blkdev_ioctl
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From: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Message-ID: <18608105-31d3-3d77-ccbb-a25bbe7e55e6@I-love.SAKURA.ne.jp>
Date: Sat, 28 Apr 2018 17:57:35 +0900
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Like I noted in a patch at

https://groups.google.com/d/msg/syzkaller-bugs/2Rw8-OM6IbM/PzdobV8kAgAJ

loop module is not thread safe. Can we use more global lock?