From mboxrd@z Thu Jan  1 00:00:00 1970
From: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Subject: Re: start_kernel(): bug: interrupts were enabled early
Date: Thu, 01 Apr 2010 09:37:51 +1100
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To: "H. Peter Anvin" <hpa@zytor.com>
Cc: Christoph Lameter <cl@linux-foundation.org>, Matthew Wilcox <matthew@wil.cx>, Yinghai Lu <yinghai@kernel.org>, Andrew Morton <akpm@linux-foundation.org>, Rabin Vincent <rabin@rab.in>, lkml <linux-kernel@vger.kernel.org>, penberg@cs.helsinki.fi, linux-arch@vger.kernel.org

On Wed, 2010-03-31 at 14:57 -0700, H. Peter Anvin wrote:
> 
> The question still remains what the incremental cost is of doing
> irqsave/irqrestore. 

The only other option is to have local_irq_enable() check a global
(system_state ?) before enabling. Almost as gross ...

Cheers,
Ben.