I upgraded my system today (usual minor package updates), and have not been able to boot into any 3-0-0-XX kernel since, despite the fact that I was using a 3.0 kernel just fine before today. I checked for questions that covered my problem and I found this question, and I tried the solution, but was still unable to boot. I've also checked for solutions in the Ubuntu bug database but I haven't been able to get any of them to work.
When I boot 3.0.0-14 (or -12 or -13) in recovery, all I get is a line like
rtc_cmos 00:05: setting system clock to <blah>
and nothing happens after that. There's no response to keyboard input, including Ctrl-Alt-Delete.
Does anyone know a solution to this problem? I'm booting in an old 2.6.38 kernel for now, but this will start getting obnoxious after I forget that I have to do this.
The system is indeed totally unresponsive to keyboard input. Neither the Magic SysRq keys nor the Ctrl-Alt-F# will work. Changing video mode at startup also does not work.
There were lots of packages that were upgraded, but the ones that could mess up the boot as far as I could tell would only be the kernel and acipid. I reinstalled those, to no avail.