[kbuild-all] Error: failed to open BPF object file: No such file or directory

Hi Martin, FYI, the error/warning still remains. tree: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git master head: 7426cedc7dad67bf3c71ea6cc29ab7822e1a453f commit: 78e60bbbe8e8f614b6a453d8a780d9e6f77749a8 bpf: selftests: Bpf_cubic and bpf_dctcp calling kernel functions date: 3 months ago config: x86_64-rhel-8.3-kselftests (attached as .config) compiler: gcc-9 (Debian 9.3.0-22) 9.3.0 reproduce (this is a W=1 build): # https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit... git remote add linus https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git git fetch --no-tags linus master git checkout 78e60bbbe8e8f614b6a453d8a780d9e6f77749a8 # save the attached .config to linux build tree make W=1 ARCH=x86_64 If you fix the issue, kindly add following tag as appropriate Reported-by: kernel test robot <lkp(a)intel.com&gt; All errors (new ones prefixed by >>): libbpf: failed to find BTF for extern 'tcp_cong_avoid_ai' [27] section: -2 -- libbpf: failed to find BTF for extern 'tcp_reno_cong_avoid' [38] section: -2 --- 0-DAY CI Kernel Test Service, Intel Corporation https://lists.01.org/hyperkitty/list/kbuild-all@lists.01.org