2 spin_unlocks are omitted in the interrupt handler.  Put them there to fix up
deadlocking on UP.
Signed-off-by: Jiri Slaby <jirislaby@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
        port = card->ports + channel;
        if (!(port->flags & ASYNC_INITIALIZED)) {
                outw(0x0000, base+0x04); /* enable interrupts */
+               spin_unlock(&card->card_lock);
                return IRQ_HANDLED;
        }
 
                tty_flip_buffer_push(tty);
        }
        outw(0x0000, base+0x04); /* enable interrupts */
+       spin_unlock(&card->card_lock);
 
        return IRQ_HANDLED;
 }