lkml.org 
[lkml]   [2014]   [Aug]   [19]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
Patch in this message
/
From
Subject[PATCH] bcache: prevent crash on changing writeback_running
Date
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


\
 
 \ /
  Last update: 2014-08-19 15:21    [W:0.051 / U:1.808 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site