Hi Yonghong, I love your patch! Perhaps something to improve: [auto build test WARNING on bpf-next/master] url: https://github.com/intel-lab-lkp/linux/commits/Yonghong-Song/bpf-Add-64bit-enum-value-support/20220502-030301 base: https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next.git master config: i386-randconfig-m021 (https://download.01.org/0day-ci/archive/20220504/202205040133.jd7yTwg5-lkp@xxxxxxxxx/config) compiler: gcc-11 (Debian 11.2.0-20) 11.2.0 If you fix the issue, kindly add following tag as appropriate Reported-by: kernel test robot <lkp@xxxxxxxxx> New smatch warnings: tools/lib/bpf/relo_core.c:348 bpf_core_fields_are_compat() warn: if(); Old smatch warnings: tools/lib/bpf/relo_core.c:349 bpf_core_fields_are_compat() warn: if(); vim +348 tools/lib/bpf/relo_core.c 314 315 /* Check two types for compatibility for the purpose of field access 316 * relocation. const/volatile/restrict and typedefs are skipped to ensure we 317 * are relocating semantically compatible entities: 318 * - any two STRUCTs/UNIONs are compatible and can be mixed; 319 * - any two FWDs are compatible, if their names match (modulo flavor suffix); 320 * - any two PTRs are always compatible; 321 * - for ENUMs, names should be the same (ignoring flavor suffix) or at 322 * least one of enums should be anonymous; 323 * - for ENUMs, check sizes, names are ignored; 324 * - for INT, size and signedness are ignored; 325 * - any two FLOATs are always compatible; 326 * - for ARRAY, dimensionality is ignored, element types are checked for 327 * compatibility recursively; 328 * - everything else shouldn't be ever a target of relocation. 329 * These rules are not set in stone and probably will be adjusted as we get 330 * more experience with using BPF CO-RE relocations. 331 */ 332 static int bpf_core_fields_are_compat(const struct btf *local_btf, 333 __u32 local_id, 334 const struct btf *targ_btf, 335 __u32 targ_id) 336 { 337 const struct btf_type *local_type, *targ_type; 338 339 recur: 340 local_type = skip_mods_and_typedefs(local_btf, local_id, &local_id); 341 targ_type = skip_mods_and_typedefs(targ_btf, targ_id, &targ_id); 342 if (!local_type || !targ_type) 343 return -EINVAL; 344 345 if (btf_is_composite(local_type) && btf_is_composite(targ_type)) 346 return 1; 347 if (btf_kind(local_type) != btf_kind(targ_type)) { > 348 if (btf_is_enum(local_type) && btf_is_enum64(targ_type)) ; 349 else if (btf_is_enum64(local_type) && btf_is_enum(targ_type)) ; 350 else return 0; 351 } 352 353 switch (btf_kind(local_type)) { 354 case BTF_KIND_PTR: 355 case BTF_KIND_FLOAT: 356 return 1; 357 case BTF_KIND_FWD: 358 case BTF_KIND_ENUM: 359 case BTF_KIND_ENUM64: { 360 const char *local_name, *targ_name; 361 size_t local_len, targ_len; 362 363 local_name = btf__name_by_offset(local_btf, 364 local_type->name_off); 365 targ_name = btf__name_by_offset(targ_btf, targ_type->name_off); 366 local_len = bpf_core_essential_name_len(local_name); 367 targ_len = bpf_core_essential_name_len(targ_name); 368 /* one of them is anonymous or both w/ same flavor-less names */ 369 return local_len == 0 || targ_len == 0 || 370 (local_len == targ_len && 371 strncmp(local_name, targ_name, local_len) == 0); 372 } 373 case BTF_KIND_INT: 374 /* just reject deprecated bitfield-like integers; all other 375 * integers are by default compatible between each other 376 */ 377 return btf_int_offset(local_type) == 0 && 378 btf_int_offset(targ_type) == 0; 379 case BTF_KIND_ARRAY: 380 local_id = btf_array(local_type)->type; 381 targ_id = btf_array(targ_type)->type; 382 goto recur; 383 default: 384 return 0; 385 } 386 } 387 -- 0-DAY CI Kernel Test Service https://01.org/lkp
