On boot, Debian shows a prompt: wait 5 seconds, or hit enter for a shell prompt. On my system, if I hit enter I get a shell prompt but none of the commands work (everything: not found). Anyway, if I then exit the shell, it eventually says cramfs: wrong magic and kernel panic: unable to mount root fs blah.
But if I don't drop to the shell, don't touch anything, it still says cramfs: wrong magic, but boots anyway without any panics. What's going on?