Re: spurious interrupt with ac kernel but not with vanilla 2.4.9

Luigi Genoni
2001-09-21T17:15:06Z

On Fri, 21 Sep 2001, Alan Cox wrote:

> > I noticed that on the abit kt7A MBs that i have, with via KT133A chipset,
> > after i installed the kernel 2.4.9-ac10 (ac11 and 12 as well),
> > at boot i get this message,
> >
> > Sep 21 11:52:11 DarkStar kernel: ice 00:0b.0
> > Sep 21 11:52:11 DarkStar kernel: spurious 8259A interrupt: IRQ7.
> > immediatelly before scsi adaptec detection and inizzializzation.
>
> Thats indicating an IRQ appeared and vanished. IRQ 7 is the IRQ that happens
> to occur for this.
>
> > I was thinking to an HW problem, but with vanilla 2.4.9 kernel I do not
> > get this message, and the code in arch/i386/kernel/i8259.c that should
> > detect this spurious interrup is just the same on those two kernels.
> > Changes are related to X86_IO_APIC, and I think this is the reason why
> > this spurious interrupt is detected, but I would like to know if i should
> > think I have some HW problem going on that stardard kernels do not detect.
>
> The APIC only applies to multiprocessor boxes unless you are building with
> uniprocessor apic support. Build a non SMP kernel without apic support
> and let me know what that does

yes, i was using a non SMP kernel with both apic and io_apic support
enabled.

actally:

with APIC support
and
without IO_APIC support

I do not get this message again, but I am so sorry, because my processor
has integrated APIC support.

I just made another test on a dual Athlon 1200 Mhz per CPU on an MB with
AMD chipset, and here this problem does not appear.

Thanx

Luigi