[PATCH 4/5] firmware: fix detecting error on register_reboot_notifier()

["Luis R. Rodriguez" <mcgrof@kernel.org>]

register_reboot_notifier() can fail, detect this and address this
failure. This has been broken since v3.11, however the chances of
this failing here is really low.

Fixes: fe304143b0c3d ("firmware: Avoid deadlock of usermodehelper lock at shutdown")
Signed-off-by: Luis R. Rodriguez <mcgrof@kernel.org>
---
 drivers/base/firmware_class.c | 9 ++++++++-
 1 file changed, 8 insertions(+), 1 deletion(-)

diff --git a/drivers/base/firmware_class.c b/drivers/base/firmware_class.c
index 3340a17e0499..7ab54f2b032f 100644
--- a/drivers/base/firmware_class.c
+++ b/drivers/base/firmware_class.c
@@ -1860,8 +1860,15 @@ static int __init firmware_class_init(void)
 	if (ret)
 		return ret;
 
-	register_reboot_notifier(&fw_shutdown_nb);
+	ret = register_reboot_notifier(&fw_shutdown_nb);
+	if (ret)
+		goto out;
+
 	return register_sysfs_loader();
+
+out:
+	unregister_fw_pm_ops();
+	return ret;
 }
 
 static void __exit firmware_class_exit(void)
-- 
2.15.0