I don't think I have any.
Check if some superIO has not irq9 configured.
Generally IRQ9 is used as ACPI SCI int. Just pressing the power button generates the IRQ for example. To make it work you need:
- Set IRQ9 in chipset as ACPI IRQ
I don't know where I would do this. I'm assuming you mean southbridge when you say chipset.
Yes. Maybe it is hardcoded in chip (IRQ9).
9: 1 276 15 99709 IO-APIC-fasteoi acpi
Huh quite big number. Is it from coreboot or legacy BIOS? Maybe some ACPI GP timer is generating the IRQ9?
Rudolf