From: Cedric Le Goater <clg@fr.ibm.com>

Add an anonymous union and ((deprecated)) to catch direct usage of the
session field.


Signed-off-by: Andrew Morton <akpm@osdl.org>
---

 include/linux/init_task.h |   11 ++++++-----
 include/linux/sched.h     |    9 +++++++--
 2 files changed, 13 insertions(+), 7 deletions(-)

diff -puN include/linux/init_task.h~add-process_session-helper-routine-deprecate-old-field include/linux/init_task.h
--- a/include/linux/init_task.h~add-process_session-helper-routine-deprecate-old-field
+++ a/include/linux/init_task.h
@@ -57,17 +57,18 @@
 	.cpu_vm_mask	= CPU_MASK_ALL,				\
 }
 
-#define INIT_SIGNALS(sig) {	\
-	.count		= ATOMIC_INIT(1), 		\
+#define INIT_SIGNALS(sig) {						\
+	.count		= ATOMIC_INIT(1), 				\
 	.wait_chldexit	= __WAIT_QUEUE_HEAD_INITIALIZER(sig.wait_chldexit),\
-	.shared_pending	= { 				\
+	.shared_pending	= { 						\
 		.list = LIST_HEAD_INIT(sig.shared_pending.list),	\
-		.signal =  {{0}}}, \
+		.signal =  {{0}}},					\
 	.posix_timers	 = LIST_HEAD_INIT(sig.posix_timers),		\
 	.cpu_timers	= INIT_CPU_TIMERS(sig.cpu_timers),		\
 	.rlim		= INIT_RLIMITS,					\
 	.pgrp		= 1,						\
-	.session	= 1,						\
+	.tty_old_pgrp   = 0,						\
+	{ .session      = 1},						\
 }
 
 extern struct nsproxy init_nsproxy;
diff -puN include/linux/sched.h~add-process_session-helper-routine-deprecate-old-field include/linux/sched.h
--- a/include/linux/sched.h~add-process_session-helper-routine-deprecate-old-field
+++ a/include/linux/sched.h
@@ -435,7 +435,12 @@ struct signal_struct {
 	/* job control IDs */
 	pid_t pgrp;
 	pid_t tty_old_pgrp;
-	pid_t session;
+
+	union {
+		pid_t session __attribute ((deprecated));
+		pid_t __session;
+	};
+
 	/* boolean value for session group leader */
 	int leader;
 
@@ -1045,7 +1050,7 @@ static inline pid_t process_group(struct
 
 static inline pid_t process_session(struct task_struct *tsk)
 {
-	return tsk->signal->session;
+	return tsk->signal->__session;
 }
 
 static inline struct pid *task_pid(struct task_struct *task)
_