Hi Song, I love your patch! Perhaps something to improve: [auto build test WARNING on bpf-next/master] url: https://github.com/0day-ci/linux/commits/Song-Liu/introduce-btf_tracing_i... base: https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next.git master config: m68k-defconfig (attached as .config) compiler: m68k-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/44d18dd3ca4645c999b4c0ec9ae232de7... git remote add linux-review https://github.com/0day-ci/linux git fetch --no-tags linux-review Song-Liu/introduce-btf_tracing_ids/20211112-150610 git checkout 44d18dd3ca4645c999b4c0ec9ae232de79648286 # save the attached .config to linux build tree COMPILER_INSTALL_PATH=$HOME/0day COMPILER=gcc-11.2.0 make.cross ARCH=m68k If you fix the issue, kindly add following tag as appropriate Reported-by: kernel test robot <lkp(a)intel.com&gt; All warnings (new ones prefixed by >>): kernel/bpf/task_iter.c: In function 'task_iter_init': 655 | task_reg_info.ctx_arg_info[0].btf_id = &btf_tracing_ids[BTF_TRACING_TYPE_TASK]; | ^ kernel/bpf/task_iter.c:660:51: warning: assignment to 'u32' {aka 'unsigned int'} from 'u32 *' {aka 'unsigned int *'} makes integer from pointer without a cast [-Wint-conversion] 660 | task_file_reg_info.ctx_arg_info[0].btf_id = &btf_tracing_ids[BTF_TRACING_TYPE_TASK]; | ^ kernel/bpf/task_iter.c:661:51: warning: assignment to 'u32' {aka 'unsigned int'} from 'u32 *' {aka 'unsigned int *'} makes integer from pointer without a cast [-Wint-conversion] 661 | task_file_reg_info.ctx_arg_info[1].btf_id = &btf_tracing_ids[BTF_TRACING_TYPE_FILE]; | ^ kernel/bpf/task_iter.c:666:50: warning: assignment to 'u32' {aka 'unsigned int'} from 'u32 *' {aka 'unsigned int *'} makes integer from pointer without a cast [-Wint-conversion] 666 | task_vma_reg_info.ctx_arg_info[0].btf_id = &btf_tracing_ids[BTF_TRACING_TYPE_TASK]; | ^ kernel/bpf/task_iter.c:667:50: warning: assignment to 'u32' {aka 'unsigned int'} from 'u32 *' {aka 'unsigned int *'} makes integer from pointer without a cast [-Wint-conversion] 667 | task_vma_reg_info.ctx_arg_info[1].btf_id = &btf_tracing_ids[BTF_TRACING_TYPE_VMA]; | ^ vim +655 kernel/bpf/task_iter.c 644 645 static int __init task_iter_init(void) 646 { 647 struct mmap_unlock_irq_work *work; 648 int ret, cpu; 649 650 for_each_possible_cpu(cpu) { 651 work = per_cpu_ptr(&mmap_unlock_work, cpu); 652 init_irq_work(&work->irq_work, do_mmap_read_unlock); 653 } 654 --- 0-DAY CI Kernel Test Service, Intel Corporation https://lists.01.org/hyperkitty/list/kbuild-all@lists.01.org