[mythtv-users] DMA problems again

[Torsten Schenkel]

On Mon, 2004-01-12 at 16:26, Craig Meyer wrote:
> 1) Acpi and Apic are two different things. Apic is used primarly on newer
> and SMP machines for the purpose of stearing extra IRQ's. It allows newer
> computers to use over 16 IRQS and SMP machines to make intterupt requests
> with both processors. ACPI is support for extra power extensions for
> better power saving etc.... If your having a DMA problem, shut off APIC
> and not ACPI.

ACK

> 2) Someone mentioned before in this thread that the 2.4 series kernel does
> not have support for shutting off APIC durring the boot sequence. He is
> mistaken, this is not just a 2.6 series option. I have been forced to use
> that boot option on my BP6 SMP machine for over a year now with a 2.4
> series kernel because otherwise the machine simply will not run Linux
> correctly. I have never recompiled the kernel for this system. If you
> can't find the command, write me personally and I will check my lilo.conf
> for the correct append mesg (note: I think its noapic)


That someone's me :-)

And there's two sorts of APIC support in the kernel:

1. APIC for SMP, that's what you can disable via the noapic option
2. Local APIC for single processors, that's what you can't disable via
boot parameter in kernels 2.4.xx

The second is the option nolapic which is a new boot option with the
2.6. kernels.

I guess now we should have it puzzled out.

BTW, its local APIC that causes trouble with the NForce2.

Torsten
-- 
Walkthrough: MythTV on Epia with PVR350 using Debian:
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