It's usually considered stupid to lock the same spinlock twice in

close succession. However, for this once we'll just call it "inspired".

But let's decide pair the lock with an unlock anyway, even if it is
boring and "square".

fs/proc/array.c

@@ -322,7 +322,7 @@ int proc_pid_stat(struct task_struct *task, char * buffer)
 	if (task->sighand) {
 		spin_lock_irq(&task->sighand->siglock);
 		collect_sigign_sigcatch(task, &sigign, &sigcatch);
-		spin_lock_irq(&task->sighand->siglock);
+		spin_unlock_irq(&task->sighand->siglock);
 	}
 	read_unlock(&tasklist_lock);