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Subject: Re: PowerPC BUG: using smp_processor_id() in preemptible code
From: Benjamin Herrenschmidt <benh@kernel.crashing.org>
To: Peter Zijlstra <a.p.zijlstra@chello.nl>
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Date: Fri, 25 Feb 2011 08:23:26 +1100
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Cc: linuxppc-dev@lists.ozlabs.org, Jeremy Fitzhardinge <jeremy@goop.org>,
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On Thu, 2011-02-24 at 22:07 +0100, Peter Zijlstra wrote:
> 
> Lovely problem :-), benh mentioned it on IRC, but I never got around
> to
> finding the email thread, thanks for the CC.
> 
> > What would be better for 2.6.38 and 2.6.37-stable?  Moving that call
> to
> > vunmap_page_range back under vb->lock, or the partial-Peter-patch
> below?
> > And then what should be done for 2.6.39?
> 
> I think you'll also need the arch/powerpc/kernel/process.c changes
> that
> cause context switches to flush the tlb_batch queues.

I don't think that's needed here as there shall be no batching happening
on the vmalloc space, but it can't hurt to merge it regardless :-)

Cheers,
Ben.