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Subject: Re: ftrace introduces instability into kernel 2.6.27(-rc2,-rc3)
From: Benjamin Herrenschmidt <benh@kernel.crashing.org>
To: Steven Rostedt <rostedt@goodmis.org>
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Date: Tue, 19 Aug 2008 14:17:11 +1000
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Cc: "Paul E. McKenney" <paulmck@linux.vnet.ibm.com>,
	Mathieu Desnoyers <mathieu.desnoyers@polymtl.ca>,
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On Mon, 2008-08-18 at 23:12 -0400, Steven Rostedt wrote:
> On Tue, 19 Aug 2008, Benjamin Herrenschmidt wrote:
> 
> > Ok, so i did a patch, but it doesn't fix the problem. So
> > there's something else whacking on the stack frames.
> 
> Is it 32 bit or 64?  I've tested the 64 bit quite a bit, but not so much 
> the 32 (my powerbook is not usually that stable).

32-bit. Reproduced on powerbook by a user, 440, 750, ...

> You might want to look at the entry.S mcount code too.

Yeah, I had a look, nothing obviously bad there, but I may just
have missed it :-)

Ben.