Re: lockup with voluntary preempt R0 and VP, KP, etc, disabled

From: Ingo Molnar
Date: Fri Sep 03 2004 - 05:37:28 EST



* Florian Schmidt <mista.tapas@xxxxxxx> wrote:

> > best would be to enable the NMI watchdog (nmi_watchdog=1 (or 2) boot
> > option) - check that it's working via the attached lockupcli.c
> > userspace code (run it as root). To have an NMI watchdog you need
> > APIC/IOAPIC support in the .config.
>
> Hmm, my local APIC kinda sux and i had all kinds of trouble using it
> [ERR count went up, stuff didn't work; XT-PIC always worked very well
> here]. So i'm kinda reluctant to compile with APIC. I suppose i can
> compile with it but turn it off via boot option? Or does the watchdog
> need a APIC that actually does stuff?

in theory you should be able to boot with just the local APIC enabled
and "nmi_watchdog=2" and get a working NMI watchdog. You'll still have
the normal PIC IRQ handling.

Ingo
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