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Subject: Re: [PATCH 7/7] powerpc/64/kdump: Use ppc_save_regs() in
	crash_setup_regs()
From: Benjamin Herrenschmidt <benh@kernel.crashing.org>
To: avorontsov@ru.mvista.com
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Date: Wed, 07 Jan 2009 16:11:08 +1100
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On Wed, 2009-01-07 at 07:04 +0300, Anton Vorontsov wrote:
> AFAICS it saves r1:
> 
>        PPC_STL r0,0*SZL(r3)
>        PPC_STL r2,2*SZL(r3)
>        PPC_STL r3,3*SZL(r3)
>        ...
>        /* go up one stack frame for SP */
>        PPC_LL  r4,0(r1)
>        PPC_STL r4,1*SZL(r3)
> 
> This fact is mentioned in the patch description:
> 
>  NOTE: The old regs dump implementation was capturing SP (r1) directly
>  as is, so you could see crash_kexec() function on top of the
> back-trace.
>  But ppc_save_regs() goes up one stack frame, so you'll not see it
>  anymore, at the top-level you'll see who actually triggered the crash
>  dump instead.
> 
> Do you see anything wrong in such behaviour?

No, just me being a bit blind looking at too many patches today :-)

Cheers,
Ben.