[PATCH] handle posix message queues with /proc/sys disabled

register_sysctl_table() fails if sysctl support is not compiled into the
kernel.  The POSIX message queue subsystem aborted it's initialization if
register_sysctl_table() fails, and that causes an oops in sys_mq_open().
The patch fixes that by ignoring failures from register_sysctl_table().

Signed-off-by; Manfred Spraul <manfred@colorfullife.com>
Signed-off-by: Adrian Bunk <bunk@stusta.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

ipc/mqueue.c

@@ -1219,11 +1219,8 @@ static int __init init_mqueue_fs(void)
 	if (mqueue_inode_cachep == NULL)
 		return -ENOMEM;
 
+	/* ignore failues - they are not fatal */
 	mq_sysctl_table = register_sysctl_table(mq_sysctl_root, 0);
-	if (!mq_sysctl_table) {
-		error = -ENOMEM;
-		goto out_cache;
-	}
 
 	error = register_filesystem(&mqueue_fs_type);
 	if (error)
@@ -1243,8 +1240,8 @@ static int __init init_mqueue_fs(void)
 out_filesystem:
 	unregister_filesystem(&mqueue_fs_type);
 out_sysctl:
-	unregister_sysctl_table(mq_sysctl_table);
-out_cache:
+	if (mq_sysctl_table)
+		unregister_sysctl_table(mq_sysctl_table);
 	if (kmem_cache_destroy(mqueue_inode_cachep)) {
 		printk(KERN_INFO
 			"mqueue_inode_cache: not all structures were freed\n");