RE: interrupts across PCI bridge(s) not handled

From: Linus Torvalds
Date: Mon Nov 03 2003 - 16:53:03 EST

On Mon, 3 Nov 2003, Charles Martin wrote:
> I do notice that bus #6, which is the backplane extender,
> has an APIC id of 0, but an APIC #0 was not enumerated. All other
> buses get assigned to the identified APICs of 8, 9 and 10.

Yes. However, I have this suspicion that that is just more confusion by
the BIOS tables.

The reason APIC #0 wasn't enumerated is that it doesn't seem to exist in
the MP tables. So not only does the PIRQ table not contain any information
about that bus, but the MP tables are very silent about it too.

I dunno.. Maybe I'm reading this wrong, but it really looks like your BIOS
tables are just pretty broken.

It would really be interesting to hear whether using ACPI enumeration
fixes it or at least whether the symptoms are different. Especially with
newer hardware, the BIOS people have only ever tested their tables with
Windows, and ACPI will have overridden any MPtable information, so..


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