reproduce: git remote add lwn git://git.lwn.net/linux.git git fetch lwn docs-next git checkout lwn/docs-next b4 shazam https://lore.kernel.org/r/50830030-dca7-4c43-bcc8-449c7cfa9fbb@gmail.com make menuconfig # enable CONFIG_COMPILE_TEST, CONFIG_WARN_MISSING_DOCUMENTS, CONFIG_WARN_ABI_ERRORS # install Sphinx 3.4.3 make htmldocs