I suspect it’s this: “Automated dependency addition to .h and .c files. This is about 790 commits, which are strictly limited to trivial addition of header dependencies. These patches make indirect dependencies explicit, and thus prepare the tree for aggressive removal of cross-dependencies from headers.”

Did a brief scan of the repo. Looks like a lot of it comes from adding new headers. This commit adds +#include <linux/wait_api.h> to 1627 files for instance.

https://git.kernel.org/pub/scm/linux/kernel/git/mingo/tip.gi...