[<prev] [next>] [thread-next>] [day] [month] [year] [list]
Message-Id: <20230628010756.70649-1-yukuai1@huaweicloud.com>
Date: Wed, 28 Jun 2023 09:07:54 +0800
From: Yu Kuai <yukuai1@...weicloud.com>
To: xni@...hat.com, logang@...tatee.com, hch@....de, song@...nel.org,
shli@...com
Cc: linux-raid@...r.kernel.org, linux-kernel@...r.kernel.org,
yukuai3@...wei.com, yukuai1@...weicloud.com, yi.zhang@...wei.com,
yangerkun@...wwe.com
Subject: [PATCH -next v2 0/2] md/raid5-cache: fix a deadlock in r5l_exit_log()
From: Yu Kuai <yukuai3@...wei.com>
Changes in v2:
- remove a now unused local variable in patch 2;
Commit b13015af94cf ("md/raid5-cache: Clear conf->log after finishing
work") introduce a new problem:
// caller hold reconfig_mutex
r5l_exit_log
flush_work(&log->disable_writeback_work)
r5c_disable_writeback_async
wait_event
/*
* conf->log is not NULL, and mddev_trylock()
* will fail, wait_event() can never pass.
*/
conf->log = NULL
patch 1 revert this patch, an patch 2 fix the original problem in a
different way.
Noted this problem is just found by code review, and I think this is
probably the reason that some mdadm tests is broken.
Yu Kuai (2):
md/raid5-cache: Revert "md/raid5-cache: Clear conf->log after
finishing work"
md/raid5-cache: fix null-ptr-deref in r5l_reclaim_thread()
drivers/md/raid5-cache.c | 25 ++++++++++---------------
1 file changed, 10 insertions(+), 15 deletions(-)
--
2.39.2
Powered by blists - more mailing lists