From mboxrd@z Thu Jan  1 00:00:00 1970
From: David Miller <davem@davemloft.net>
Subject: Re: [Patch] Micrel KS8695 intergrated ethernet driver
Date: Tue, 09 Dec 2008 01:05:29 -0800 (PST)
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From: Christoph Hellwig <hch@infradead.org>
Date: Tue, 9 Dec 2008 03:57:39 -0500

> On Mon, Dec 08, 2008 at 11:05:18AM +0000, Daniel Silverstone wrote:
> > > > +                       mapping = dma_map_single(ksp->dev, skb->data,
> > > > +                                                MAX_RXBUF_SIZE,
> > > > +                                                DMA_FROM_DEVICE);
> > > I take it that dma_map_single() can never fail on ARM?
> > 
> > No it can't. It essentially boils down to some pointer arithmetic on
> > this platform.
> 
> You should check for errors anyway.  The driver might be ported to an
> architecture where it can fail (e.g. the SOC block gets reused), ARM
> variants may come up where it can fail, or people might use the driver
> as an example for their own new driver.

Agreed.