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Subject: Re: start_kernel(): bug: interrupts were enabled early
From: Benjamin Herrenschmidt <benh@kernel.crashing.org>
To: Yinghai Lu <yinghai@kernel.org>
Cc: Andrew Morton <akpm@linux-foundation.org>, Rabin Vincent <rabin@rab.in>,
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Date: Thu, 01 Apr 2010 09:31:27 +1100
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On Wed, 2010-03-31 at 13:47 -0700, Yinghai Lu wrote:
> > perhaps the second one isn't needed?  Perhaps no architecture
> requires
> > that local interrupts be disabled across the above initialisations?
>         
> spin_unlock_irq from arm is different from other archs?

No, it's not, it will enable IRQs and thats illegal to do so early
during boot. We've been over that one again and again, the problem is
that people want to keep using that instead of irqsave/restore because
it's a nano-optimisation on x86... oh well...

Cheers,
Ben.