From: Pingfan Liu <piliu@redhat.com>
Date: Wed, 15 Feb 2023 11:23:40 +0000 (+0800)
Subject: dm: add cond_resched() to dm_wq_work()
X-Git-Tag: v6.1.16~98
X-Git-Url: https://www.infradead.org/git/?a=commitdiff_plain;h=7f093695b49a0e46d2f1ad0c641dd04f8d20acd9;p=users%2Fdwmw2%2Flinux.git

dm: add cond_resched() to dm_wq_work()

commit 0ca44fcef241768fd25ee763b3d203b9852f269b upstream.

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

Cc: stable@vger.kernel.org
Signed-off-by: Pingfan Liu <piliu@redhat.com>
Acked-by: Ming Lei <ming.lei@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---

diff --git a/drivers/md/dm.c b/drivers/md/dm.c
index c9d034c952a4e..212441671554c 100644
--- a/drivers/md/dm.c
+++ b/drivers/md/dm.c
@@ -2578,6 +2578,7 @@ static void dm_wq_work(struct work_struct *work)
 			break;
 
 		submit_bio_noacct(bio);
+		cond_resched();
 	}
 }