I'm trying to use a custom compiled kernel on my MythTV box. It's currently running Debian. It uses LVM2 and with the stock kernel, it boots right up. For whatever reason when I compile my own kernel it won't boot. The kernel I'm trying to get to work is a 2.6.11 Debian kernel.

I have inculded LVM support in the kernel. I also ran the mkinitrd command to make an initrd file. I set up lilo to point to the right vmlinuz file and initrd file. But I get the following error when I boot.

Please append a correct "root=" option

It then kernel panics. The root= option should be correct since it is the same root= option that boots the stock 2.6.8 kernel. I just don't understand. Any help would be appreciated.

Is the new root on a lvm2 partition?
If it is its not the standard /dev/hd* device.

Double check to see where your root partition indeed is.