Subject: Re: [PATCH v3 05/10] net/fec: add dual fec support for mx28

From: Shawn Guo <[email-masked]>
Date: Fri, 7 Jan 2011 15:00:57 +0800

Hi Uwe,

On Thu, Jan 06, 2011 at 08:10:47AM +0100, Uwe Kleine-König wrote:
> Hello Shawn,
[...]
> > > > +     /*
> > > > +      * enet-mac reset will reset mac address registers too,
> > > > +      * so need to reconfigure it.
> > > > +      */
> > > > +     if (fec_is_enetmac) {
> > > > +             memcpy(&temp_mac, dev->dev_addr, ETH_ALEN);
> > 		  ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
> > > > +             writel(cpu_to_be32(temp_mac[0]), fep->hwp + FEC_ADDR_LOW);
> > > > +             writel(cpu_to_be32(temp_mac[1]), fep->hwp + FEC_ADDR_HIGH);
> > > where is the value saved to temp_mac[]?  For me it looks you write
> > > uninitialized data into the mac registers.
> > 
> > memcpy above.
> oops.  right.  I looked for something like
> 
> 	temp_mac[0] = dev->dev_addr[0] << $shiftfor0 | ...
> 
> which AFAIK is what you want here.  memcpy is sensible to (at least)
> endian issues.  If you ask me factor out the setting of the mac address
> in probe to a function and use that here, too.
> 
The memcpy of mac address is being widely used in fec and other
network drivers, and I do not prefer to change something so common
in this patch set.

-- 
Regards,
Shawn