[9fans] usb and dns suddenly not working

["Joel C. Salomon" <joelcsalomon@gmail.com>]

"But I didn't change anything!"

I've checked /rc/bin/termrc against my local history and the version
up on sources (via the web interface), and cannot find any significant
differences -- in fact, I've reverted to a previous version and the
problem remained.

Both USB and internet connectivity have suddenly stopped working on my
laptop.  When I run usbstart, I get
  usb/usbmouse: /dev/usb/1/ep0data: '/dev/usb/1/ep0data' does not exist

More critically, no matter what I do, I get
  % ip/ping google.com
  ip/ping: couldn't dial icmp!google.com!1: cs: temporary failure:
dns: dns failure
To make this problem more fun to diagnose, I can't copy files off my
laptop *except* via the network -- which used to work!

Does this problem sound familiar to someone?

--Joel