From: Shan Hai <shan.hai@xxxxxxxxxx> The writeback thread would exit with a lock held when the cache device is detached via sysfs interface, fix it by releasing the held lock before exiting the while-loop. Signed-off-by: Shan Hai <shan.hai@xxxxxxxxxx> Signed-off-by: Coly Li <colyli@xxxxxxx> Tested-by: Shenghui Wang <shhuiw@xxxxxxxxxxx> Cc: stable@xxxxxxxxxxxxxxx #4.17+ --- drivers/md/bcache/writeback.c | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-) diff --git a/drivers/md/bcache/writeback.c b/drivers/md/bcache/writeback.c index 6be05bd7ca67..08c3a9f9676c 100644 --- a/drivers/md/bcache/writeback.c +++ b/drivers/md/bcache/writeback.c @@ -685,8 +685,10 @@ static int bch_writeback_thread(void *arg) * data on cache. BCACHE_DEV_DETACHING flag is set in * bch_cached_dev_detach(). */ - if (test_bit(BCACHE_DEV_DETACHING, &dc->disk.flags)) + if (test_bit(BCACHE_DEV_DETACHING, &dc->disk.flags)) { + up_write(&dc->writeback_lock); break; + } } up_write(&dc->writeback_lock); -- 2.18.0