IRQ / interrupt conflict issues with megaraid and Linux

Ever since Linux kernels beyond 2.6.24.3, I've been unable to boot my HP Netserver LH3.

It gives a kernel panic with a variety of messages that always include "common_interrupt+0x38/0x39"

I tried everything from updating the BIOS and firmware, to myriads of differing kernel configurations (at 4 hours per compile, imagine the agony).

I also tried booting with every combination of the kernel boot parameters acpi=off, noapic, nolapic, irqpoll, etc that I could imagine. No dice.

In final desperation, I began unplugging PCI cards one by one before finally disconnecting the SDLT drive from the Netraid SCSI. Et voila!

It seems that in later kernels or versions of udev, sharing the SCSI bus with the LH3 drives causes conflicts.

I have an additional AHA SCSI card in the machine, so will try connecting the SDLT to that and see how it goes.