Cannot use UUID with self-compiled kernel (Hardy)

[Jason Crain]

On Fri, July 25, 2008 5:03 am, Mumia W. wrote:
> Hello. I'm having a problem with a self-compiled kernel. I can't use
> UUID to specify my root partition; however, using "root=/dev/sda8"
> works. When I try to boot using the UUID, I get this:
>
>  > VFS: Cannot open root device "xxxxx" or unknown-block(0,0)
>
> That's somewhat annoying as you can imagine. I triple-checked to be sure
> that my kernel contains everything needed to boot. Here is the boot
> stanza that fails (with the UUID value removed):
>
>  > title        Ubuntu 8.04.1, kernel 2.6.26-beamer1
>  > root        (hd0,7)
>  > kernel        /boot/vmlinuz-2.6.26-beamer1 root=UUID=[...] ro quiet
> splash
>  > quiet
>
> However, this boot stanza succeeds:
>
>  > title        Ubuntu 8.04.1, kernel 2.6.26-beamer1
>  > root        (hd0,7)
>  > kernel        /boot/vmlinuz-2.6.26-beamer1 root=/dev/sda8 ro
>  > boot
>
> It's the UUID that's failing, but I can't find where I can enable UUID's
> in my kernel. Note that I'm not using an initrd--everything should be
> compiled into the kernel.
>

When you run without an initrd, you have to have static /dev entries,
correct?  Or at least enough /dev entries to get the root filesystm
mounted.  The /dev/disk/by-uuid entries are created by udev, and I can't
think of a sensible way they could be created statically.  I suggest
either enable initrd or stick with root=/dev/sda8.