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Subject: Re: Kernel hang on PS3 with SMP
From: Geoff Levand <geoff@infradead.org>
To: Peter Zijlstra <a.p.zijlstra@chello.nl>
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Date: Fri, 28 Oct 2011 18:33:25 -0700
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Cc: cbe-oss-dev@lists.ozlabs.org, Andre Heider <a.heider@gmail.com>,
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Hi,

On Thu, 2011-10-27 at 18:17 -0700, Geoff Levand wrote: 
> I verified that indeed 317f394160e9beb97d19a84c39b7e5eb3d7815a8
> 'sched: Move the second half of ttwu() to the remote cpu' introduces
> the hang.

After some more digging I found that it seems a short while after
startup ps3_smp_message_pass() gets called with a PPC_MSG_RESCHEDULE,
but then there is no corresponding call to scheduler_ipi() on the target
cpu.

I'll do some more work on it and verify that this is what is actually
happening.

-Geoff