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Subject: Re: CONFIG_PROVE_LOCKING broken on 83xx (and all of powerpc?)
From: Benjamin Herrenschmidt <benh@kernel.crashing.org>
To: "Ira W. Snyder" <iws@ovro.caltech.edu>
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On Wed, 2010-09-08 at 19:52 -0700, Ira W. Snyder wrote:
> 
> I will attempt to get the debugger to stop at start_kernel. I'm having
> trouble driving the JTAG debugger (a BDI2000). I have used Denx's
> guide
> [1] in the past, but the section on debugging the kernel itself is now
> missing.
> 
> [1] http://www.denx.de/wiki/view/DULG/DebuggingLinuxKernel
> 
> I'll keep trying. 

start_kernel might be too late...

You can also hack thing :-) Like in the asm, before machine_init(),
stick something in the DABR and put a HW breakpoint with the BDI2000 on
the Data Access exception handler to "catch" when it faults.

Ben.