This patch (as1148) adds a new "snoop" message to usbfs when a device
file is opened, identifying the process responsible.  This comes in
extremely handy when trying to determine which program is doing some
unwanted USB access.
Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
        smp_wmb();
        list_add_tail(&ps->list, &dev->filelist);
        file->private_data = ps;
+       snoop(&dev->dev, "opened by process %d: %s\n", task_pid_nr(current),
+                       current->comm);
  out:
        if (ret) {
                kfree(ps);