diff options
| author | Stefan Bader <stefan.bader@canonical.com> | 2015-11-29 18:44:49 -0800 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2016-03-03 15:07:09 -0800 |
| commit | 9e761c1b436d04823baa161c294fddc524750015 (patch) | |
| tree | a565e419a9a912cf1d30ae5cf3c9c0e7b42f90fe /drivers/md | |
| parent | b38798df6cca121e0df4c6a500408070eba24264 (diff) | |
bcache: prevent crash on changing writeback_running
commit 8d16ce540c94c9d366eb36fc91b7154d92d6397b upstream.
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>
Signed-off-by: Jens Axboe <axboe@fb.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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) |