Hi Song, I love your patch! Yet something to improve: [auto build test ERROR on bpf-next/master] url: https://github.com/0day-ci/linux/commits/Song-Liu/bpf-introduce-bpf_get_b... base: https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next.git master config: riscv-randconfig-r025-20210825 (attached as .config) compiler: riscv64-linux-gcc (GCC) 11.2.0 reproduce (this is a W=1 build): wget https://raw.githubusercontent.com/intel/lkp-tests/master/sbin/make.cross -O ~/bin/make.cross chmod +x ~/bin/make.cross # https://github.com/0day-ci/linux/commit/e32271f38de34ebc8cc48176d9f1f0972... git remote add linux-review https://github.com/0day-ci/linux git fetch --no-tags linux-review Song-Liu/bpf-introduce-bpf_get_branch_trace/20210824-140315 git checkout e32271f38de34ebc8cc48176d9f1f0972182414e # save the attached .config to linux build tree mkdir build_dir COMPILER_INSTALL_PATH=$HOME/0day COMPILER=gcc-11.2.0 make.cross O=build_dir ARCH=riscv SHELL=/bin/bash 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 >>): riscv64-linux-ld: kernel/bpf/trampoline.o: in function `__bpf_prog_enter': --- 0-DAY CI Kernel Test Service, Intel Corporation https://lists.01.org/hyperkitty/list/kbuild-all@lists.01.org