The patch below does not apply to the 4.14-stable tree. If someone wants it applied there, or to any other stable or longterm tree, then please email the backport, including the original git commit id to stable@vger.kernel.org.

thanks,

greg k-h

------------------ original commit in Linus's tree ------------------

From f54d801dda14942dbefa00541d10603015b7859c Mon Sep 17 00:00:00 2001

From: Coly Li colyli@suse.de Date: Fri, 28 Jun 2019 19:59:44 +0800 Subject: [PATCH] bcache: destroy dc->writeback_write_wq if failed to create dc->writeback_thread

Commit 9baf30972b55 ("bcache: fix for gc and write-back race") added a new work queue dc->writeback_write_wq, but forgot to destroy it in the error condition when creating dc->writeback_thread failed.

This patch destroys dc->writeback_write_wq if kthread_create() returns error pointer to dc->writeback_thread, then a memory leak is avoided.

Fixes: 9baf30972b55 ("bcache: fix for gc and write-back race") Signed-off-by: Coly Li colyli@suse.de Cc: stable@vger.kernel.org Signed-off-by: Jens Axboe axboe@kernel.dk

diff --git a/drivers/md/bcache/writeback.c b/drivers/md/bcache/writeback.c index 262f7ef20992..21081febcb59 100644 --- a/drivers/md/bcache/writeback.c +++ b/drivers/md/bcache/writeback.c @@ -833,6 +833,7 @@ int bch_cached_dev_writeback_start(struct cached_dev *dc) "bcache_writeback"); if (IS_ERR(dc->writeback_thread)) { cached_dev_put(dc); + destroy_workqueue(dc->writeback_write_wq); return PTR_ERR(dc->writeback_thread); } dc->writeback_running = true;