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Subject: Re: [BUG] 2.6.25-rc5-mm1 kernel panic with "Exception: 501 " on
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From: Benjamin Herrenschmidt <benh@kernel.crashing.org>
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> Beats me.  Maybe we're still enabling interrupts too early.  But the new
> semaphore code got fixed (didn't it?)

Won't lockdep/irqtrace warn if that happens ? You don't yet have the
lockdep patches for ppc64 (I'm still trying to find out why they break
iSeries) but it should warn of such a spurrious IRQ enable on other
archs too... At least, from a quick look at the code, it -seems- that it
does have such a test.

Cheers,
Ben.