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Date: Fri, 16 Jan 2009 21:26:38 +0000 (GMT)
From: "Maciej W. Rozycki" <macro@linux-mips.org>
To: Jan Beulich <jbeulich@novell.com>
cc: Ingo Molnar <mingo@elte.hu>, tglx@linutronix.de,
       linux-kernel@vger.kernel.org, hpa@zytor.com
Subject: Re: [PATCH] x86: avoid early crash in disable_local_APIC()
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On Fri, 16 Jan 2009, Jan Beulich wrote:

> Is this with a config that has X86_IO_APIC off (i.e. one the practical use of
> which I never understood, and hence easily forget to consider)? Otherwise
> I can't see how that could happen.

 A lot of systems have a P6-class CPU which has a local APIC and no I/O 
APIC in the chipset.  My old laptop was an example of one.  It saves some 
memory to have X86_IO_APIC disabled on such systems, while still being 
able to use the local APIC for the NMI watchdog and PeMo.

  Maciej