From mboxrd@z Thu Jan  1 00:00:00 1970
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Subject: Re: CONFIG_FRAME_POINTER [was [PATCH] x86: BUILD_IRQ say .text]
From: Benjamin Herrenschmidt <benh@kernel.crashing.org>
To: Hugh Dickins <hugh@veritas.com>
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	<20080724104459.GI28817@elte.hu>
	<Pine.LNX.4.64.0807251839190.20617@blonde.site>
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Date: Sat, 26 Jul 2008 07:46:13 +1000
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Cc: Linuxppc-dev@ozlabs.org, Ingo Molnar <mingo@elte.hu>,
	the arch/x86 maintainers <x86@kernel.org>,
	linux-kernel@vger.kernel.org, Mike Travis <travis@sgi.com>
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On Fri, 2008-07-25 at 19:45 +0100, Hugh Dickins wrote:
> 
> I've Cc'ed Ben and linuxppc-dev because I wonder if they're aware
> that several options (I got it from LATENCYTOP, but I think LOCKDEP
> and FTRACE and some others) are doing a "select FRAME_POINTER",
> which forces CONFIG_FRAME_POINTER=y on PowerPC, even though
> FRAME_POINTER is not an option offered on PowerPC.  The
> resulting kernels appear to run okay, but I was surprised.

Because the option just does nothing for us ? :-) We always have frame
pointers on powerpc except in some case for leaf functions. I don't know
if the option has any actual effect on the later, but I don't think we
have a case where doing either way would break things.

Cheers,
Ben.