The bug was reported to https://bugzilla.kernel.org/show_bug.cgi?id=76901. Currently, Mika asked for the support to apply his patch, which adds more debug messages to the suspected function, and get the dmesg log. I've submitted the dmesg for his diagnosis.
** Bug watch added: Linux Kernel Bug Tracker #76901 http://bugzilla.kernel.org/show_bug.cgi?id=76901 -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/1290189 Title: Unable to hotplug ExpressCard in 12.04.4 To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/linux-lts-saucy/+bug/1290189/+subscriptions -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs