up-to-date: kernel 3.2.54. (Always read current kernel sources!) This topic has maintainer rfree

BuildId is the --build-id option for compiler/linker that result in unique Build ID number being added to the resulting binary like vmlinux into it's vmlinux/asm-notes section.

https://fedoraproject.org/wiki/Releases/FeatureBuildId

To get rid of it e.g. to produce SameKernel builds, edit the main Makefile and change --build-id to =none, as done by the Mempo script in https://github.com/mempo/deterministic-kernel the important part is

sed -i Makefile  -e 's/--build-id/--build-id=none/g' 

targeting the top-level Makefile (seems to work on amd64 builds on debian).

Perhaps certain architectures already remove this --build-id, or remove it along with removing entire .notes section, see vmlinux/asm-notes