dm: add cond_resched() to dm_wq_requeue_work()

Otherwise the while() loop in dm_wq_requeue_work() can result in a
"dead loop" on systems that have preemption disabled. This is
particularly problematic on single cpu systems.

Fixes: 8b211aaccb915 ("dm: add two stage requeue mechanism")
Cc: stable@vger.kernel.org
Signed-off-by: Mike Snitzer <snitzer@kernel.org>

1 files changed, 1 insertions, 0 deletions

diff --git a/drivers/md/dm.c b/drivers/md/dm.c
index 15b91959e433..adb002b8648d 100644
--- a/drivers/md/dm.c
+++ b/drivers/md/dm.c
@@ -1009,6 +1009,7 @@ static void dm_wq_requeue_work(struct work_struct *work)
 		io->next = NULL;
 		__dm_io_complete(io, false);
 		io = next;
+		cond_resched();
 	}
 }