From 7e5c1e830b2310359a4cfbbf89895dde4abd996a Mon Sep 17 00:00:00 2001
From: Milan Broz <mbroz@redhat.com>
Date: Fri, 8 Feb 2008 02:09:49 +0000
Subject: [PATCH] dm: add missing memory barrier to dm_suspend

Add memory barrier to fix atomic_read of pending value.

Signed-off-by: Milan Broz <mbroz@redhat.com>
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
---
 drivers/md/dm.c | 1 +
 1 file changed, 1 insertion(+)

diff --git a/drivers/md/dm.c b/drivers/md/dm.c
index f2d24eb3208..466a6bf0742 100644
--- a/drivers/md/dm.c
+++ b/drivers/md/dm.c
@@ -1410,6 +1410,7 @@ int dm_suspend(struct mapped_device *md, unsigned suspend_flags)
 	while (1) {
 		set_current_state(TASK_INTERRUPTIBLE);
 
+		smp_mb();
 		if (!atomic_read(&md->pending) || signal_pending(current))
 			break;