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Date: Tue, 31 Jul 2007 10:06:54 +0200
From: John Sigler <linux.kernel@free.fr>
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Subject: BIOS implementors disabling the LAPIC
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I have several systems here where Linux tells me:
Local APIC disabled by BIOS -- you can enable it with "lapic"

As far as I understand, the Local APIC was integrated directly to the 
CPU 12-15 years ago. Why would a BIOS implementor choose to disable it?

(And what does it mean to "disable" the LAPIC?)

Note: the motherboard does not provide an IO-APIC.

I've ask the kernel to re-enable the LAPIC, and was able to use OProfile 
in hardware counter mode, i.e. it seems to work fine.

Regards.