The kernel starts up the first userspace process, which it identifies as 'init'. It loads this from the root filesystem, and must be told where in the root filesystem to look for it. This is usually done as a kernel argument (init=/blah/blah) supplied by the bootloader, or can be a pre-defined kernel argument built into the kernel at compile time. Your error message suggests that either the kernel wasn't told what to look for, or it couldn't locate what was specified when it did look for it.
Last edited by theNbomr; 08-13-2011 at 02:27 PM.