From f03449f8829a218e9518fb455d0e5305aa1784a5 Mon Sep 17 00:00:00 2001
From: Oleg Nesterov <oleg@redhat.com>
Date: Thu, 2 Apr 2009 16:57:58 -0700
Subject: [PATCH] --- yaml --- r: 139679 b: refs/heads/master c:
 90bc8d8b1a38f1ab131a2399a202e1889db95de8 h: refs/heads/master i:   139677:
 a0d66c63f1aa22c12209f6fc9eb99a7766a53c32   139675:
 3c87c74b584b8d62b11427e1acaf7da352869989   139671:
 369ba4b5fa30125bcc7a68bf7439475d5e8f8613   139663:
 10a3cebea39bf5deb6e0092b2502aa85101d51e7   139647:
 138eab6fee5c199db58315c9ea06863436a038a3 v: v3

---
 [refs]              |  2 +-
 trunk/kernel/exit.c | 30 ++++++++++++++++++------------
 2 files changed, 19 insertions(+), 13 deletions(-)

diff --git a/[refs] b/[refs]
index b5f041de964e..47cb8fd8f56e 100644
--- a/[refs]
+++ b/[refs]
@@ -1,2 +1,2 @@
 ---
-refs/heads/master: 6d7b2f5f9e88902b19f91d0c8a7ef58a5455f1a2
+refs/heads/master: 90bc8d8b1a38f1ab131a2399a202e1889db95de8
diff --git a/trunk/kernel/exit.c b/trunk/kernel/exit.c
index 167e1e3ad7c6..0c06b9efae3b 100644
--- a/trunk/kernel/exit.c
+++ b/trunk/kernel/exit.c
@@ -1417,6 +1417,18 @@ static int wait_task_zombie(struct task_struct *p, int options,
 	return retval;
 }
 
+static int *task_stopped_code(struct task_struct *p, bool ptrace)
+{
+	if (ptrace) {
+		if (task_is_stopped_or_traced(p))
+			return &p->exit_code;
+	} else {
+		if (p->signal->flags & SIGNAL_STOP_STOPPED)
+			return &p->signal->group_exit_code;
+	}
+	return NULL;
+}
+
 /*
  * Handle sys_wait4 work for one task in state TASK_STOPPED.  We hold
  * read_lock(&tasklist_lock) on entry.  If we return zero, we still hold
@@ -1427,7 +1439,7 @@ static int wait_task_stopped(int ptrace, struct task_struct *p,
 			     int options, struct siginfo __user *infop,
 			     int __user *stat_addr, struct rusage __user *ru)
 {
-	int retval, exit_code, why;
+	int retval, exit_code, *p_code, why;
 	uid_t uid = 0; /* unneeded, required by compiler */
 	pid_t pid;
 
@@ -1437,22 +1449,16 @@ static int wait_task_stopped(int ptrace, struct task_struct *p,
 	exit_code = 0;
 	spin_lock_irq(&p->sighand->siglock);
 
-	if (unlikely(!task_is_stopped_or_traced(p)))
-		goto unlock_sig;
-
-	if (!ptrace && p->signal->group_stop_count > 0)
-		/*
-		 * A group stop is in progress and this is the group leader.
-		 * We won't report until all threads have stopped.
-		 */
+	p_code = task_stopped_code(p, ptrace);
+	if (unlikely(!p_code))
 		goto unlock_sig;
 
-	exit_code = p->exit_code;
+	exit_code = *p_code;
 	if (!exit_code)
 		goto unlock_sig;
 
 	if (!unlikely(options & WNOWAIT))
-		p->exit_code = 0;
+		*p_code = 0;
 
 	/* don't need the RCU readlock here as we're holding a spinlock */
 	uid = __task_cred(p)->uid;
@@ -1608,7 +1614,7 @@ static int wait_consider_task(struct task_struct *parent, int ptrace,
 	 */
 	*notask_error = 0;
 
-	if (task_is_stopped_or_traced(p))
+	if (task_stopped_code(p, ptrace))
 		return wait_task_stopped(ptrace, p, options,
 					 infop, stat_addr, ru);