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Date: Thu, 12 Jun 2014 17:15:13 -0500
From: Segher Boessenkool <segher@kernel.crashing.org>
To: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Subject: Re: power and percpu: Could we move the paca into the percpu area?
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Cc: Tejun Heo <htejun@gmail.com>, linuxppc-dev@lists.ozlabs.org,
 Christoph Lameter <cl@gentwo.org>
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On Fri, Jun 13, 2014 at 07:57:08AM +1000, Benjamin Herrenschmidt wrote:
> On Thu, 2014-06-12 at 07:26 -0500, Segher Boessenkool wrote:
> > But, indeed, it does look like GCC doesn't use it.  It seems to me
> > that
> > some ABI forbade userland (or non-libraries or whatever) from using
> > it.
> > I'll see what I can find out.
> 
> I can still use -ffixed-cr5 for safety no ?

Yes, definitely, and in fact you have to if GCC changes to not have cr5
fixed by default (which may or may not happen).  It will be good
documentation in either case :-)


Segher