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Date:   Thu, 13 May 2010 09:17:13 -0700
From:   David Daney <david.s.daney@gmail.com>
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To:     Ralf Baechle <ralf@linux-mips.org>
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Subject: Re: [PATCH 9/9] tracing: MIPS: cleanup of the address space checking
References: <cover.1273669419.git.wuzhangjin@gmail.com> <86404e31ca5c4c33b785bad7f6223ac775f4f879.1273669419.git.wuzhangjin@gmail.com> <4BEAE19D.40502@gmail.com> <20100513161357.GA5810@linux-mips.org>
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On 05/13/2010 09:13 AM, Ralf Baechle wrote:
> On Wed, May 12, 2010 at 10:13:01AM -0700, David Daney wrote:
>
>> The kernel is always compiled with -msym32, so the patch is a bit pointless.
>
> Not quite true.  Some systems only have enough memory for the exception
> vectors in the low 512MB of physical address space, so these can't use
> an -msym32 kernel.
>
> My general impression is that hardware designers "design" address maps by
> throwing darts over their shoulder after a few pints ;-)
>

Well it was mostly a rhetorical point.  Of course -msym32 is not 
universal, but it is more common than not I would say.  Because of that, 
we should take a few more minutes and figure out how to make ftrace work 
well with it.

David Daney