Comment 34 for bug 771788

I used a simple script to test the Jockey handler for Nvidia. The result looks like the following:

...
>>> ndb = nvidia.NvidiaDriverBase(b, '173')
>>> print ndb
xorg:nvidia_173([NvidiaDriverBase, nonfree, enabled] NVIDIA accelerated graphics driver)
>>> ndb.used()
False
>>> ndb.enabled()
True
>>> ndb.changed()
False

So it looks like the "changed" attribute is set to False as a default in superclass jockey.handlers.KernelModuleHandler, but there is no way that this value can ever be set to True with the current code. This means that the "used" attribute, that requires that the "changed" and "enabled" properties be True, will never be True.

The documentation for the "changed" property is "Return if the module has been enabled/disabled at least once." I am really not sure what is the dependency between "changed" and "used" makes sense.