tree:   https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git master
head:   a96bfed64c8986d6404e553f18203cae1f5ac7e6
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/?id=78e60bbbe8e8f614b6a453d8a780d9e6f77749a8
        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@intel.com>

All errors (new ones prefixed by >>):

   libbpf: failed to find BTF for extern 'tcp_reno_cong_avoid' [38] section: -2
>> Error: failed to open BPF object file: No such file or directory
--
   libbpf: failed to find BTF for extern 'tcp_cong_avoid_ai' [27] section: -2
>> Error: failed to open BPF object file: No such file or directory

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0-DAY CI Kernel Test Service, Intel Corporation
https://lists.01.org/hyperkitty/list/kbuild-all@lists.01.org