From mboxrd@z Thu Jan  1 00:00:00 1970
From: Thomas Gleixner <tglx@linutronix.de>
Subject: Re: [ANNOUNCE] 3.6.5-rt15
Date: Thu, 15 Nov 2012 18:59:54 +0100 (CET)
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To: Grant Likely <grant.likely@secretlab.ca>
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On Wed, 14 Nov 2012, Grant Likely wrote:
> Hey Thomas,
> 
> I get a kernel bug when going from rt14 to rt15. It appears that
> preempt_lazy on my ARM platform causes (or exposes) the following
> backtrace on boot. I'm basing this on the only relevant change between
> rt14 and rt15 is the typo fix that enables PREEMPT_LAZY. I also see
> the problem on -rt16 and -rt17.
> 
> (full boot log also attached below)
> 
> The actual backtrace changes every time, but it is always related to
> an rt_spin_lock() call.
> 
> This is on a TI AM3894 platform which is equivalent to a TI8160
> without the DSP. The board support isn't mainlined, but there is
> nothing particularly exotic about the changes. It is primarily device
> drivers and device driver data. Cortex-A8 platform.
> 
> Any thoughts on how to debug this?

Probably by staring at the patch to the ASM code in arch/arm. I bet I
messed that up somehow :)

Thanks,

	tglx