So I made a textbook error, and after I had got everything else working nicely on 12.04, thought I would try to upgrade my Nvidia drivers to "current", since that was recommended, in the hope it would improve 3D performance.
Slight problem: I can no longer boot my kernel. The error reads, in part:
Kernel panic - not syncing: VFS: Unable to mount root fs on unknown-block(0,0) PID: 1, comm: swapper/0 Not tainted 3.2.0-31-generic #50-Ubuntu
That's followed by a call trace, which I'd rather not have to retype by hand unless it's necessary.
Recovery mode also does not work, giving the same error, but preceded by a whole dump of text. The two extra lines which precede the error above look interesting:
VFS: Cannot open root device "UUID=[long string of hex]" or unknown-block(0,0) Please append a correct "root=" boot option; here are the available partitions:
followed by the same kernel panic message as above.
It's not a disk or filesystem error, as if I choose the previous kernel or a LiveCD it mounts fine.
Most of the suggestions I can find seem to revolve around purging the Nvidia drivers, but they tend to assume that users are able to boot the kernel, at least in text mode. Is there anything I can do via e.g. chroot or something?
Are the Nvidia drivers even involved, or is that just a coincidence? The root partition is on an Nvidia RAID device, but I don't know whether that is significant.
Thanks in advance for any help.