Comment 6 for bug 687692

To avoid restarting, you should be able to recover wifi by executing the following commands:
sudo rmmod r8192se_pci
sudo modprobe r8192se_pci

However, sometimes (and I can't seem to figure any pattern to it) the modprobe command will completely lock up my system. Also, you will lose wifi again. I wind up executing these commands many times per hour.