From: Cornelia Huck <cornelia.huck@de.ibm.com>
Date: Mon, 4 Dec 2006 14:40:54 +0000 (+0100)
Subject: [S390] cio: Make ccw_dev_id_is_equal() more robust.
X-Git-Tag: v2.6.20-rc1~34^2~40^2~15^2~6
X-Git-Url: https://err.no/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=ce26a8532fd062ccd3f3c589a4be269a2dc20f00;p=linux-2.6

[S390] cio: Make ccw_dev_id_is_equal() more robust.

Using memcmp to compare ccw_dev_id implies that the whole structure (incl.
padding) has always been completely initialized to sane values. Comparing
the structures field by field doesn't make such assumptions.

Signed-off-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
---

diff --git a/include/asm-s390/cio.h b/include/asm-s390/cio.h
index cabd5bb74b..d927850309 100644
--- a/include/asm-s390/cio.h
+++ b/include/asm-s390/cio.h
@@ -278,7 +278,10 @@ struct ccw_dev_id {
 static inline int ccw_dev_id_is_equal(struct ccw_dev_id *dev_id1,
 				      struct ccw_dev_id *dev_id2)
 {
-	return !memcmp(dev_id1, dev_id2, sizeof(struct ccw_dev_id));
+	if ((dev_id1->ssid == dev_id2->ssid) &&
+	    (dev_id1->devno == dev_id2->devno))
+		return 1;
+	return 0;
 }
 
 extern int diag210(struct diag210 *addr);