[openib-general] Disabling IRQ #201 message

[Roland Dreier]

    Robert> I'm debugging some code that is reading files in
    Robert> /sys/class/infiniband/.  Other than that the HCA isn't
    Robert> doing anything at all. The dropped interrupt occurs
    Robert> whether or not I am doing anything. I can reboot the
    Robert> machine and just let it sit there and the message will
    Robert> occur after a while. After the message, files which
    Robert> require interacting with the HCA
    Robert> e.g. /sys/class/infiniband/mthca0/ports/1/state become
    Robert> unreadable. Read calls block for a long time and finally
    Robert> timeout with an EOF indication.

I think I may see a kernel bug that can cause this.  In the meantime
booting with the "noirqdebug" kernel option should work around the
problem.

 - R.