diff options
| author | Stefan Bader <stefan.bader@canonical.com> | 2015-11-29 18:44:49 -0800 |
|---|---|---|
| committer | Sasha Levin <sasha.levin@oracle.com> | 2016-02-01 14:53:56 -0500 |
| commit | ad148665b58dcd0a4336188ce4a2194d7f353c5f (patch) | |
| tree | f2573d39a011f52431c92b830e4d8545735cacb1 /drivers/md | |
| parent | d5402134c27d66e83295ae2961772b89bc6a50bc (diff) | |
bcache: prevent crash on changing writeback_running
[ Upstream commit 8d16ce540c94c9d366eb36fc91b7154d92d6397b ]
Added a safeguard in the shutdown case. At least while not being
attached it is also possible to trigger a kernel bug by writing into
writeback_running. This change adds the same check before trying to
wake up the thread for that case.
Signed-off-by: Stefan Bader <stefan.bader@canonical.com>
Cc: Kent Overstreet <kent.overstreet@gmail.com>
Cc: stable@vger.kernel.org
Signed-off-by: Jens Axboe <axboe@fb.com>
Signed-off-by: Sasha Levin <sasha.levin@oracle.com>
Diffstat (limited to 'drivers/md')
| -rw-r--r-- | drivers/md/bcache/writeback.h | 3 |
1 files changed, 2 insertions, 1 deletions
diff --git a/drivers/md/bcache/writeback.h b/drivers/md/bcache/writeback.h index 0a9dab187b79..073a042aed24 100644 --- a/drivers/md/bcache/writeback.h +++ b/drivers/md/bcache/writeback.h @@ -63,7 +63,8 @@ static inline bool should_writeback(struct cached_dev *dc, struct bio *bio, static inline void bch_writeback_queue(struct cached_dev *dc) { - wake_up_process(dc->writeback_thread); + if (!IS_ERR_OR_NULL(dc->writeback_thread)) + wake_up_process(dc->writeback_thread); } static inline void bch_writeback_add(struct cached_dev *dc) |