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Date: Wed, 24 Aug 2011 14:00:10 +1000
From: David Gibson <dwg@au1.ibm.com>
To: "K.Prasad" <prasad@linux.vnet.ibm.com>
Subject: Re: [PATCH 2/2] [PowerPC Book3E] Introduce new ptrace debug feature
	flag
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On Tue, Aug 23, 2011 at 02:57:56PM +0530, K.Prasad wrote:
> On Tue, Aug 23, 2011 at 03:09:31PM +1000, David Gibson wrote:
> > On Fri, Aug 19, 2011 at 01:23:38PM +0530, K.Prasad wrote:
> > > 
> > > While PPC_PTRACE_SETHWDEBUG ptrace flag in PowerPC accepts
> > > PPC_BREAKPOINT_MODE_EXACT mode of breakpoint, the same is not intimated to the
> > > user-space debuggers (like GDB) who may want to use it. Hence we introduce a
> > > new PPC_DEBUG_FEATURE_DATA_BP_EXACT flag which will be populated on the
> > > "features" member of "struct ppc_debug_info" to advertise support for the
> > > same on Book3E PowerPC processors.
> > 
> > I thought the idea was that the BP_EXACT mode was the default - if the
> > new interface was supported at all, then BP_EXACT was always
> > supported.  So, why do you need a new flag?
> > 
> 
> Yes, BP_EXACT was always supported but not advertised through
> PPC_PTRACE_GETHWDBGINFO. We're now doing that.

I can see that.  But you haven't answered why.

-- 
David Gibson			| I'll have my music baroque, and my code
david AT gibson.dropbear.id.au	| minimalist, thank you.  NOT _the_ _other_
				| _way_ _around_!
http://www.ozlabs.org/~dgibson