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..MP-BIOS bug: 8254 timer not connected to IO-APIC

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H_TeXMeX_H:
Upon booting FC5 I get the following message:

..MP-BIOS bug: 8254 timer not connected to IO-APIC

What does this mean ? ... I've googled it, but I still don't know what it means. As far as I know everything works fine on FC5, but this message bothers me ... it wasn't there on FC4.

This is on my notebook
2.8 Ghz Pentium 4
1 GB RAM
GeForce 4 420 Go
SiS chipset

Richard Harris:
I just installed FC5 on an AMD 2200 and got the same error. You find out anything yet?

H_TeXMeX_H:
I submitted a bug report some time ago:

https://bugzilla.redhat.com/bugzilla/show_bug.cgi?id=187411

H_TeXMeX_H:
This bug is definitely caused by the BIOS ... updating it may or may not help depending on what the manufacturers decide to update.

H_TeXMeX_H:
I got a question:

Well, I've been looking at the kernel sources recently tring to see what goes wrong. It looks like the error is generated within a function in linux-2.6.1.x/arch/i386/kernel/io_apic.c called check_timer. The error only gets printed if pin1 is anything but -1 and the function timer_irq_works returns zero indicating that the timer IRQs are "defunct". There is a comment about this function (timer_irq_works):

There is a nasty bug in some older SMP boards, their mptable lies
about the timer IRQ. We do the following to work around the situation:

- timer IRQ defaults to IO-APIC IRQ
- if this function detects that timer IRQs are defunct, then we fall
back to ISA timer IRQs

I think this shouldn't happen because I don't have an older SMP board ... any ideas ?

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