Last night I thought it would be fun to try to suspend my laptop with the 3G USB modem still plugged in and connected. This morning when I woke it up I had no keyboard.
Ctrl+Alt+F1 worked to switch to a text console (when I pressed it twice). The text console wasn't garbled, which was nice. killall gnome-settings-daemon or gnome-screensaver didn't fix anything. Suspending and resuming again didn't fix things either (not that there's any reason why it should). When I noticed that Ctrl+Alt+Backspace didn't work in X, I realized this wasn't an X grab issue.
/var/log/Xorg.0.log has a series of errors like this:
(EE) AT Translated Set 2 keyboard: Device has changed - disabling. (WW) AT Translated Set 2 keyboard: Release failed (Invalid argument)
Sadly, there are no timestamps. I think this was printed once on resume, and then once on every VT switch.
xinput still lists "AT Translated Set 2 Keyboard" among its devices.
I remember now -- before suspending I had used
sudo showkeys -s
in an xterm (trying to see the scan code of the ThinkVantage button). Could've
mucked up the keyboard mode?
Alt+SysRq+R (raw mode) didn't help, even when followed by more VT switches. I think I'm gonna restart the X server. Or reboot the whole PC, Ubuntu notifier is showing its reboot icon again...
Meta: I wrote this post on March 6, and then decided it wasn't interesting enough to post. And then posted it accidentally on March 20.
Update: looks like bug 327175.