From: Wei Yongjun <yongjun_wei@trendmicro.com.cn>
Date: Fri, 12 Oct 2012 15:59:42 +0000 (+0100)
Subject: dm mpath: fix check for null mpio in end_io fn
X-Git-Tag: firefly_0821_release~3680^2~1825^2~7
X-Git-Url: http://demsky.eecs.uci.edu/git/?a=commitdiff_plain;ds=inline;h=a71a261f5c39685698f7f1970dc7046b36e132d1;p=firefly-linux-kernel-4.4.55.git

dm mpath: fix check for null mpio in end_io fn

The mpio dereference should be moved below the BUG_ON NULL test
in multipath_end_io().

spatch with a semantic match was used to found this.
(http://coccinelle.lip6.fr/)

Signed-off-by: Wei Yongjun <yongjun_wei@trendmicro.com.cn>
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
---

diff --git a/drivers/md/dm-mpath.c b/drivers/md/dm-mpath.c
index d778563a4ffd..573bd04591bf 100644
--- a/drivers/md/dm-mpath.c
+++ b/drivers/md/dm-mpath.c
@@ -1309,13 +1309,14 @@ static int multipath_end_io(struct dm_target *ti, struct request *clone,
 {
 	struct multipath *m = ti->private;
 	struct dm_mpath_io *mpio = map_context->ptr;
-	struct pgpath *pgpath = mpio->pgpath;
+	struct pgpath *pgpath;
 	struct path_selector *ps;
 	int r;
 
 	BUG_ON(!mpio);
 
 	r  = do_end_io(m, clone, error, mpio);
+	pgpath = mpio->pgpath;
 	if (pgpath) {
 		ps = &pgpath->pg->ps;
 		if (ps->type->end_io)