[PATCH] futex: init error ckeck

[Akinobu Mita <akinobu.mita@gmail.com>]

This patch checks register_filesystem() and kern_mount() return
values.

Cc: Ingo Molnar <mingo@redhat.com>
Signed-off-by: Akinobu Mita <akinobu.mita@gmail.com>

---
 kernel/futex.c |   10 ++++++++--
 1 file changed, 8 insertions(+), 2 deletions(-)

Index: work-fault-inject/kernel/futex.c
===================================================================
--- work-fault-inject.orig/kernel/futex.c
+++ work-fault-inject/kernel/futex.c
@@ -1857,10 +1857,16 @@ static struct file_system_type futex_fs_
 
 static int __init init(void)
 {
-	unsigned int i;
+	int i = register_filesystem(&futex_fs_type);
+
+	if (i)
+		return i;
 
-	register_filesystem(&futex_fs_type);
 	futex_mnt = kern_mount(&futex_fs_type);
+	if (IS_ERR(futex_mnt)) {
+		unregister_filesystem(&futex_fs_type);
+		return PTR_ERR(futex_mnt);
+	}
 
 	for (i = 0; i < ARRAY_SIZE(futex_queues); i++) {
 		INIT_LIST_HEAD(&futex_queues[i].chain);