[PATCH] __group_complete_signal: remove bogus BUG_ON

Commit e56d090

   [PATCH] RCU signal handling

made this BUG_ON() unsafe. This code runs under ->siglock,
while switch_exec_pids() takes tasklist_lock.

Signed-off-by: Oleg Nesterov <oleg@tv-sign.ru>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

kernel/signal.c

@@ -868,7 +868,6 @@ __group_complete_signal(int sig, struct task_struct *p)
 		if (t == NULL)
 			/* restart balancing at this thread */
 			t = p->signal->curr_target = p;
-		BUG_ON(t->tgid != p->tgid);
 
 		while (!wants_signal(sig, t)) {
 			t = next_thread(t);