From mboxrd@z Thu Jan  1 00:00:00 1970
From: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Subject: Re: [RFC 1/3] hvc_console: rework setup to replace irq functions
	with callbacks
Date: Mon, 13 Oct 2008 19:36:12 +1100
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>  	if (--hp->count == 0) {
> -		if (hp->ops->notifier_del)
> -			hp->ops->notifier_del(hp, hp->data);
> -
>  		/* We are done with the tty pointer now. */
>  		hp->tty = NULL;
>  		spin_unlock_irqrestore(&hp->lock, flags);
>  
> +		if (hp->ops->notifier_del)
> +			hp->ops->notifier_del(hp, hp->data);
> +

I will try. Of course the risk here is that the interrupt happens
after we set hp->tty to NULL, so we probably need to check within the
interrupt handler for a NULL tty. I haven't checked if that's the case
(I'm not in front of the code right now).

Ben.