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Date: Fri, 14 Dec 2007 22:39:17 -0800
From: Greg KH <gregkh@suse.de>
To: Benjamin Herrenschmidt <benh@kernel.crashing.org>,
	Kay Sievers <kay.sievers@vrfy.org>
Subject: Re: Fix Firmware class name collision
Message-ID: <20071215063917.GA14942@suse.de>
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Cc: PowerPC dev list <Linuxppc-dev@ozlabs.org>,
	Markus Rechberger <markus.rechberger@amd.com>,
	Timur Tabi <timur@freescale.com>
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On Sat, Dec 15, 2007 at 05:14:29PM +1100, Benjamin Herrenschmidt wrote:
> 
> On Fri, 2007-12-14 at 14:40 -0800, Greg KH wrote:
> > On Tue, Dec 04, 2007 at 07:28:00PM -0600, Timur Tabi wrote:
> > > Scott Wood wrote:
> > >
> > >> The physical address certainly is useful when you have more than one 
> > >> device of the same name.
> > >
> > > What I meant was that the physical address isn't helpful by itself.
> > >
> > >> So then you'd get "firmware-ucc.e01024".  What if there's another ucc at  
> > >> e0102480?  For devices with longer names, you'd have even less precision 
> > >> in the address.
> > >
> > > Maybe we need to consider a more sophisticated algorithm, one that 
> > > guarantees that the device name in its entirety is preserved?  Either that, 
> > > or replace the physical address with something shorter, like the offset to 
> > > the root node only?  That way, ucc.e0102400 because just ucc.2400.
> > 
> > You should do something :)
> > 
> > In the near future (2.6.26) there will not be a limit on the size of the
> > file name, so we should not have this problem anymore.
> 
> Not even .25 ? damn ! Any way that fix can be fastracked ? This
> limitation has been a major PITA for some time now (this is just -one-
> example where it gets in the way).

I'll let Kay answer that, last he said, it involves a _lot_ of changes
throughout the kernel :(

thanks,

greg k-h