Messages in this thread Patch in this message | | | From | Stefan Bader <> | Subject | [PATCH] bcache: prevent crash on changing writeback_running | Date | Tue, 19 Aug 2014 15:01:33 +0200 |
| |
commit a664d0f05a2ec02c8f042db536d84d15d6e19e81 bcache: fix crash on shutdown in passthrough mode
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> --- drivers/md/bcache/writeback.h | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-)
diff --git a/drivers/md/bcache/writeback.h b/drivers/md/bcache/writeback.h index 0a9dab1..073a042 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) -- 1.9.1
| |