He's not asking for that. He's an experienced Android kernel hacker. He knows the difference between kernel and userland. He's informing B&N that their kernel source is incomplete. B&N is required by the GPL to release the full source of the kernel, build instructions and everything they compile directly into it (read: not 'apps') in order for another developer to be able to compile the full kernel. All of that is required by the GPL. If you don't follow it, you're not permitted to redistribute works under the license.