reproduce:
        # https://git.kernel.org/pub/scm/linux/kernel/git/bristot/linux.git/commit/?id=4ab413bca202fe480bb9fb8e6e1e6a556d50b0c5
        git remote add bristot git://git.kernel.org/pub/scm/linux/kernel/git/bristot/linux
        git fetch --no-tags bristot tracing_makefiles
        git checkout 4ab413bca202fe480bb9fb8e6e1e6a556d50b0c5
        make W=1 O=/tmp/kselftest headers
        make W=1 O=/tmp/kselftest -C tools/testing/selftests
        make W=1 O=/tmp/kselftest -C tools/testing/selftests/bpf