Can irq conflicts still happen?
 

I'm having a problem with my D-Link DWL g650 wireless card. After it is inserted in my laptop it works fine for a few minutes and then the laptop freezes completely. I'm using the madwifi drivers.

cat /proc/interrupts shows that there are two "yenta", the Radeon graphics
card and ath0 (the nic) on irq 16. Furthermore, if i call ifup on my wired nic,
this is also assigned to irg 16, so that's a total of 5 modules on 1 irq!
I've had the laptop running with the wireless nic for a whole day without
problems, and I noticed that in /proc/interrupts it was listed before the Radeon
in sequence; normally when it locks up it is listed last. Does this have any significance?

Any good ideas on how to resolve this freezing problem?

You could disable PNP in the BIOS. That tends to let linux read the IRQ's and assign them properly.

There is no option for non-pnp OS in the bios. It is a cardbus nic, so it should be handled by the hotplug system. Is there a way to tell
hotplug to prefer or exclude certain irqs for its devices or is this simply not possible?

Problem solved. I tried things like changing the order of module loading and giving pci arguments to the kernel, but this was not the problem at all. I started looking at the network setup and changed the channel of my wireless ad-hoc network to 9 instead of 1, and that
made all the difference. No more lock-ups. So after all the laptop was handling the devices fine even though they were using the same irq.
Why using channel 1 made the whole system freeze I just can't get my head around, but now it just works :)

Thanks for posting back with the solution that worked for you kjeldsen, and congrats on solving the problem. This will be a big help to future readers who might encounter the same issue -- J.W.

Welcome to LQ!