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Date: Tue, 2 Aug 2016 22:31:25 -0500
From: Josh Poimboeuf <jpoimboe@redhat.com>
To: Steven Rostedt <rostedt@goodmis.org>
Cc: Thomas Gleixner <tglx@linutronix.de>, Ingo Molnar <mingo@kernel.org>,
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        Byungchul Park <byungchul.park@lge.com>
Subject: Re: [PATCH 05/19] x86/dumpstack: fix function graph tracing stack
 dump reliability issues
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On Tue, Aug 02, 2016 at 11:21:04PM -0400, Steven Rostedt wrote:
> On Tue, 2 Aug 2016 23:18:57 -0400
> Steven Rostedt <rostedt@goodmis.org> wrote:
> 
> > On Tue, 2 Aug 2016 22:12:33 -0500
> > Josh Poimboeuf <jpoimboe@redhat.com> wrote:
> > 
> > 
> > > Sounds good.  I was thinking I could also add a similar define to
> > > indicate whether an arch passes the return address stack pointer to
> > > ftrace_push_return_trace().  HAVE_FUNCTION_GRAPH_RET_ADDR_PTR?
> > >   
> > 
> > If you are making this function global, might as well make all pass
> > that pointer when you do the conversion. I don't think we need a define
> > to differentiate it.
> > 
> 
> Bah, I was thinking of your ftrace_graph_ret_addr() function. /me needs
> to go to bed.
> 
> Anyway, if we have to add a parameter, we probably need to update all
> the callers anyway. We do need to add a parameter for this, right?

Yeah, we do need to add a parameter to ftrace_push_return_trace().  But
callers which don't implement it could just pass zero like they do with
'fp'.

-- 
Josh