From 1035a22105381f0a5e1f362ba976910b593dbe6a Mon Sep 17 00:00:00 2001
From: Oleg Nesterov <oleg@tv-sign.ru>
Date: Fri, 8 Dec 2006 02:36:07 -0800
Subject: [PATCH] --- yaml --- r: 43492 b: refs/heads/master c:
 915935041281c64589e2b7fe38437be22567fb6f h: refs/heads/master v: v3

---
 [refs]                |  2 +-
 trunk/fs/proc/array.c | 16 ++++------------
 2 files changed, 5 insertions(+), 13 deletions(-)

diff --git a/[refs] b/[refs]
index 1b7dd3bb4aec..3eaddc700479 100644
--- a/[refs]
+++ b/[refs]
@@ -1,2 +1,2 @@
 ---
-refs/heads/master: 24ec839c431eb79bb8f6abc00c4e1eb3b8c4d517
+refs/heads/master: 915935041281c64589e2b7fe38437be22567fb6f
diff --git a/trunk/fs/proc/array.c b/trunk/fs/proc/array.c
index 25e917fb4739..b0cd014a39bd 100644
--- a/trunk/fs/proc/array.c
+++ b/trunk/fs/proc/array.c
@@ -346,20 +346,13 @@ static int do_task_stat(struct task_struct *task, char * buffer, int whole)
 	sigemptyset(&sigcatch);
 	cutime = cstime = utime = stime = cputime_zero;
 
-	mutex_lock(&tty_mutex);
 	rcu_read_lock();
 	if (lock_task_sighand(task, &flags)) {
 		struct signal_struct *sig = task->signal;
-		struct tty_struct *tty = sig->tty;
-
-		if (tty) {
-			/*
-			 * sig->tty is not stable, but tty_mutex
-			 * protects us from release_dev(tty)
-			 */
-			barrier();
-			tty_pgrp = tty->pgrp;
-			tty_nr = new_encode_dev(tty_devnum(tty));
+
+		if (sig->tty) {
+			tty_pgrp = sig->tty->pgrp;
+			tty_nr = new_encode_dev(tty_devnum(sig->tty));
 		}
 
 		num_threads = atomic_read(&sig->count);
@@ -395,7 +388,6 @@ static int do_task_stat(struct task_struct *task, char * buffer, int whole)
 		unlock_task_sighand(task, &flags);
 	}
 	rcu_read_unlock();
-	mutex_unlock(&tty_mutex);
 
 	if (!whole || num_threads<2)
 		wchan = get_wchan(task);