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Subject: Re: Fix small race in 44x tlbie function
From: Benjamin Herrenschmidt <benh@kernel.crashing.org>
To: Kumar Gala <galak@kernel.crashing.org>
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Date: Thu, 09 Aug 2007 17:01:31 +1000
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Cc: Todd Inglett <tinglett@us.ibm.com>, linuxppc-dev@ozlabs.org,
	Paul Mackerras <paulus@samba.org>, Volkmar Uhlig <vuhlig@us.ibm.com>,
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On Thu, 2007-08-09 at 01:35 -0500, Kumar Gala wrote:
> >>>> Did you actually see this happen?
> >>>
> >>> Yes.
> >>
> >> When?
> >>
> >> We don't have critical wired to anything, I don't expect watchdog to
> >> cause another fault.. so just wondering.
> >
> > On debug (trace) interrupts on blue gene.
> 
> Do you know why the debug code caused a fault?

Sure, it may access vmalloc space for example, which can cause a TLB
miss...

Ben.