Comment 9 for bug 217659

The panic itself is caused by the following upstream commit:

commit ac019360fe311dd6aa11b358a02eb3a61675882e
Author: Jeff Garzik <email address hidden>
Date: Sat Oct 20 13:45:57 2007 +0200

    [Bluetooth] Eliminate checks for impossible conditions in IRQ handler

    Our info structure and info->hdev is always passed to the IRQ handler,
    so we don't have to worry about these checks in every interrupt.

    Leave a BUG_ON() just to help unwary programmers, but these could
    probably be removed as well.

    Signed-off-by: Jeff Garzik <email address hidden>
    Signed-off-by: Marcel Holtmann <email address hidden>

The change was to remove a check which would print the error message and return by a BUG_ON statement that causes an Oops. Since the error was there before, this seems to be a race that already was there but was handled less fatally. I am not sure whether it is possible for an IRQ to be triggered between pcmcia_request_irq and dtl1_open (which fills the info->hdev) but it somehow sounds like it.