Thanks John for the release() reminder...indeed that does get called no matter how my app is closed...exactly what I was looking for! The problem that I am trying to resolve takes place when I rmmod my driver. I get a total system crash with a kernel panic, an oops of 0 and an "In interrupt handler -not syncing- message. My assumption is that (my driver uses irqs and requests and gets handlers) the irq is not being freed for some reason and the handler (that has just been removed by rmmod) is being called and whamo. Am I looking for the correct problem? In release, I try to disable interrupts and free all the irqs that I have requested and I really think that I do that. What am I missing? Do I have to do something to release the irq handler other than free_irq? -- Best regards, David Stroupe Keyed-Up Software 5307 Faireast Court Arlington, Texas 76018-1683 817/557-4903 voice 817/472-0408 fax -- Kernelnewbies: Help each other learn about the Linux kernel. Archive: http://mail.nl.linux.org/kernelnewbies/ FAQ: http://kernelnewbies.org/faq/