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Date: Wed, 20 Aug 2008 17:44:41 -0400 (EDT)
From: Steven Rostedt <rostedt@goodmis.org>
To: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Subject: Re: ftrace introduces instability into kernel 2.6.27(-rc2,-rc3)
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Cc: Eran Liberty <liberty@extricom.com>,
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On Thu, 21 Aug 2008, Benjamin Herrenschmidt wrote:

> 
> > > As you can see, it restores r1 -before- it pops r24..r31 off
> > > the stack ! I let you imagine what happens if an interrupt happens
> > > just in between those two instructions (mr and lmw). We don't do
> > > redzones on our ABI, so basically, the registers end up corrupted
> > > by the interrupt.
> > 
> > Ouch!  You've disassembled this without -pg too, and it does not have this 
> > bug? What version of gcc do you have?
> 
> Oops, should have mentioned it ;-)
> 
> 4.2.3 (Ubuntu 4.2.3-2ubuntu7)

I'm running a 4.3.1 (Debian 4.3.1-2) on my powerbook. Perhaps the issue is 
already taken care of.

-- Steve