Re: [RFC/PATCH 5/5] powerpc: Allow ptrace write to pt_regs trap

Benjamin Herrenschmidt [off-list ref] wrote on 05/29/2007 
11:41:40 PM:

On Tue, 2007-05-29 at 17:41 +0200, Ulrich Weigand wrote:

quoted

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)

Um?  I see this in the PTRACE_POKEUSR case in arch_ptrace:

                if (index == PT_ORIG_R3)
                        break;



Mit freundlichen Gruessen / Best Regards

Ulrich Weigand

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