asix driver module in ubuntu-based images causes system hang on ifdown

So for a while I've been chasing problems in networking, mostly trying to find
a USB dongle that supports AP master mode. It turns out that part of my frustration
has been related to *wired* ethernet, specifically dongles that use the asix driver

Using two different Ubunutu-based RCN images:
and also a maverick image from 2 or 3 weeks ago, I've found that any wired
ethernet dongle that uses the asix driver module will work just fine until you
try to ifdown the interface -- then you get a hard lock up. (My frustration was
that I kept attributing this to WiFi driver problems, since otherwise the wired
ethernet seemed to work just fine, so I thought the wired side was solid.)

So in the mean time I've switched to a different wired ethernet dongle, but it
seems like there should be no reason that the asix driver in the Ubuntu arm
repos should be having problems -- but it does.