[BUG] 2.6.25-rc5-mm1 kernel panic with "Exception: 501 " on powerpc

[Benjamin Herrenschmidt]

> 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.