diff --git a/fs/exec.c b/fs/exec.c
index 8fccc276d40d..9f9f931ef949 100644
--- a/fs/exec.c
+++ b/fs/exec.c
@@ -798,7 +798,7 @@ static int de_thread(struct task_struct *tsk)
 	if (!thread_group_leader(tsk)) {
 		leader = tsk->group_leader;
 
-		sig->notify_count = -1;
+		sig->notify_count = -1;	/* for exit_notify() */
 		for (;;) {
 			write_lock_irq(&tasklist_lock);
 			if (likely(leader->exit_state))
diff --git a/kernel/exit.c b/kernel/exit.c
index 413c81ec858e..879ed6e1c883 100644
--- a/kernel/exit.c
+++ b/kernel/exit.c
@@ -877,6 +877,7 @@ static void exit_notify(struct task_struct *tsk, int group_dead)
 		state = EXIT_DEAD;
 	tsk->exit_state = state;
 
+	/* mt-exec, de_thread() is waiting for us */
 	if (thread_group_leader(tsk) &&
 	    tsk->signal->notify_count < 0 &&
 	    tsk->signal->group_exit_task)