Re: APIC problem report

[Ingo Molnar <mingo@elte.hu>]

* Christopher Schramm <debian@shakaweb.org> wrote:

> Thanks for the quick replay, Ingo!
>
> Following your request, I installed Debian 5.0. Had to use noapic 
> again for getting the boot media to work (think it utilizes 
> 2.6.26).
>
> The kernel panic is the same for all three systems: "not syncing: 
> IO-APIC + timer doesn't work!".
>
> The installed system had the same problem (2.6.26 again), then I 
> compiled 2.6.28.8 (with default config). Booting that one with 
> APIC enabled throws the known "MP-BIOS bug" message, but then 
> continues booting - no kernel panic.
>
> I will try Knoppix' kernel config and your git code, when I find 
> some spare time.

By the looks of it, chances are that various APIC fixes and 
robustization patches might have fixed your problem:

 691874f: x86: I/O APIC: timer through 8259A second-chance
 03be750: x86: I/O APIC: keep the timer IRQ masked during set-up
 24742ec: x86: I/O APIC: unmask the second-chance timer interrupt
 d11d579: x86: I/O APIC: AEOI timer acknowledgement clean-ups

These first showed up in v2.6.27. Which would match your reported 
symptoms of v2.6.26 failig and 2.6.28 working. The bootup warning
about a BIOS problem is still there because there is an underlying 
problem - we just work it around and fall back more robustly.

	Ingo