Are you using the grub .config menu from LL or from another OS? If another OS, a few, notably SolydX and Debian don't update their grub .config files along with the LL upgrade. The two I mention here won't even display kernel options until you update grub for them. If you are not familiar with grub don't try to update the other menus from their respective systems or LL may not boot. If this is your issue let me know. There is a workaround, but it requires returning control of grub to LL first, and being able to boot LL correctly first, and then returning grub control to the other OS, and copying and pasting the corrected grub entries for LL into the other OS grub .config. and removing one command.
TC