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Subject: Re: [RFC/PATCH 5/5] powerpc: Allow ptrace write to pt_regs trap
From: Benjamin Herrenschmidt <benh@kernel.crashing.org>
To: Ulrich Weigand <Ulrich.Weigand@de.ibm.com>
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Date: Wed, 30 May 2007 07:41:40 +1000
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On Tue, 2007-05-29 at 17:41 +0200, Ulrich Weigand wrote:
> This doesn't look sufficient.  If you want GDB to use the save/ 
> restore style means of handling interrupted calls (like i386), 
> at the very least we also need the capability to *write* the 
> orig_gpr3 field, which is currently prohibited.  (I don't know 
> why this is case, though.) 

It's not prohibited afaik ... we allow writing to everything <= MQ (39)
on 32 bits and <= CCR (38) on 64 bits and ORIG_R3 qualifies (34)

Ben.