Re: 2.6.19-rc <-> ThinkPads

Len Brown
2006-11-01T03:18:17Z

The BIOS disables the LAPIC for a reason.
A couple of years ago Linux made the mistake of enabling the LAPIC
that the BIOS disabled, and all hell broke loose.
We fixed that bug about a year ago, but left "lapic"
to force it on for those where forcing it to be enabled actually
works (eg. some folks want the NMI profiling on their IOAPIC-less laptop)

But if you force the lapic to be enabled, you are running the system
in a mode not supported by the manufacturer and you are on your own.

I don't see an indication that this is a bug.
If it used to work and it is important to you,
then run the old software where it used to work --
because chances are good that it worked by accident.

-Len

On Tuesday 31 October 2006 22:01, Adrian Bunk wrote:
> FYI:
>
> Subject : Thinkpad R50p: boot fail with (lapic && on_battery)
> References : http://lkml.org/lkml/2006/10/31/333
> Submitter : Ernst Herzberg <earny@net4u.de>
> Status : submitter was asked to bisect
>
> It seems to be completely unrelated (except that it's also a ThinkPad),
> but it might be worth a try whether a (non-SMP) kernel without APIC
> support fixes the issues after resume.
>
> Hugh, your laptop seems to be a non-SMP laptop.
> Do you have APIC enabled, and if yes does disabling help?
>
> cu
> Adrian
>
>
> VERSION = 2
> PATCHLEVEL = 6
> SUBLEVEL = 19
> EXTRAVERSION = -rc4
> NAME=ThinkPad Killer
>
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