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Date:   Sun, 17 Jul 2022 23:38:25 -0700
From:   Christoph Hellwig <hch@infradead.org>
To:     ming.lei@redhat.com
Cc:     linux-block@vger.kernel.org
Subject: use of the system work queue in ublk
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Hi Ming,

it seems like ublk uses schedule_work to stop the device, which
includes a del_gendisk.  I'm a little fearful this will gets us into
lockdep chains of death once syzbot or Tetsu notice it.

That being said, I don't reall understand the design of
ublk_daemon_monitor_work, which is only used to kick off other
work to start with.