Re: [PATCH] irq: fix possible null-pointer deref irq_domain_to_irq

[Jamie Iles <jamie@jamieiles.com>]

On Thu, Nov 10, 2011 at 10:53:03AM +0000, Jamie Iles wrote:
> It is optional for an irqdomain to have a to_irq() method, and for
> simple domains they often don't require any operations at all - just
> hwirq to Linux irq translation.  Check we have valid ops before
> dereferencing them.
> 
> Patch originally by Rob Herring.
> 
> Suggested-by: Rob Herring <robherring2@gmail.com>

Naturally git send-email doesn't know how to convert this into a CC, so 
Rob is now CC'd!

Jamie

> Cc: Thomas Gleixner <tglx@linutronix.de>
> Cc: Grant Likely <grant.likely@secretlab.ca>
> Signed-off-by: Jamie Iles <jamie@jamieiles.com>
> ---
> 
> Rob, I can't see that you've already posted this but I didn't want to
> hold Marc's GIC patches up.
> 
>  include/linux/irqdomain.h |    2 +-
>  1 files changed, 1 insertions(+), 1 deletions(-)
> 
> diff --git a/include/linux/irqdomain.h b/include/linux/irqdomain.h
> index 99834e58..78a1e66 100644
> --- a/include/linux/irqdomain.h
> +++ b/include/linux/irqdomain.h
> @@ -74,7 +74,7 @@ struct irq_domain {
>  static inline unsigned int irq_domain_to_irq(struct irq_domain *d,
>  					     unsigned long hwirq)
>  {
> -	if (d->ops->to_irq)
> +	if (d->ops && d->ops->to_irq)
>  		return d->ops->to_irq(d, hwirq);
>  	if (WARN_ON(hwirq < d->hwirq_base))
>  		return 0;
> -- 
> 1.7.4.1
>