Mad, Beautiful Ideas
Broadcom B43 Drivers on Ubuntu

My recent Dell Mini 10 purchase came with a Broadcom BCM4312 Wifi interface. And it worked great...with the Ubuntu 8.04 install that was stock. That wasn't going to work for me. I wanted the (the Alpha) 10.04 install. Shortly after upgrading, however, my Wifi stopped working entirely. So, I found this bug, happy the problem wasn't only me. Hell, for a while, I had to use NDISwrapper to use Wifi at all.

Eventually, I downloaded the compat-wireless package from Linux Wireless, and started running my wireless interface in PIO mode, which worked okay. I could get on the wifi at a handful of places I really needed it (home, office), but not much else. It was a challenge. Hell, I had trouble on our enterprise Wifi, which uses the same SSID across our entire campus. I could get on at a small handful of locations, but not others. No idea why.

Eventually, I was getting fed up with this, so I hit up the Ubuntu forums, and finally found the answer that stabilized my Wifi experience. I had to create a b43.conf file in my /etc/modprobe.d folder, with the following:

 options b43 pio=1 qos=0

Apparently the QOS code was occasionally forcing me to have to take my wireless down and reboot the interface in order to use it. Since that change, my wifi has been almost seamless (I still get intermittent disconnects, but they come right back up, that is either the sign of a hacking attempt, or misproperly configured Wifi, I'm leaning toward the latter). It's been great. And, it seems that in a forthcoming Ubuntu Kernel, the bug should be fixed for real, which I'm really looking forward to. I (and many others) wish that this had been resolved prior to Ubuntu 10.04 shipping, but with any luck, this won't be a regression for 10.10 and beyond.