From: David Howells <dhowells@redhat.com>

Make key_serial() an inline function rather than a macro if CONFIG_KEYS=y. 
This prevents double evaluation of the key pointer and also provides better
type checking.

Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
---

 include/linux/key.h |    5 ++++-
 1 file changed, 4 insertions(+), 1 deletion(-)

diff -puN include/linux/key.h~keys-make-key_serial-a-function-if-config_keys=y include/linux/key.h
--- a/include/linux/key.h~keys-make-key_serial-a-function-if-config_keys=y
+++ a/include/linux/key.h
@@ -264,7 +264,10 @@ extern int keyring_add_key(struct key *k
 
 extern struct key *key_lookup(key_serial_t id);
 
-#define key_serial(key) ((key) ? (key)->serial : 0)
+static inline key_serial_t key_serial(struct key *key)
+{
+	return key ? key->serial : 0;
+}
 
 #ifdef CONFIG_SYSCTL
 extern ctl_table key_sysctls[];
_