Hi Charlie, kernel test robot noticed the following build warnings: [auto build test WARNING on 4cece764965020c22cff7665b18a012006359095] url: https://github.com/intel-lab-lkp/linux/commits/Charlie-Jenkins/dt-bindings-riscv-Add-vendorid-and-archid/20240412-121709 base: 4cece764965020c22cff7665b18a012006359095 patch link: https://lore.kernel.org/r/20240411-dev-charlie-support_thead_vector_6_9-v1-6-4af9815ec746%40rivosinc.com patch subject: [PATCH 06/19] riscv: Extend cpufeature.c to detect vendor extensions config: riscv-defconfig (https://download.01.org/0day-ci/archive/20240412/202404122206.TkXKhj29-lkp@xxxxxxxxx/config) compiler: clang version 19.0.0git (https://github.com/llvm/llvm-project 8b3b4a92adee40483c27f26c478a384cd69c6f05) reproduce (this is a W=1 build): (https://download.01.org/0day-ci/archive/20240412/202404122206.TkXKhj29-lkp@xxxxxxxxx/reproduce) If you fix the issue in a separate patch/commit (i.e. not just a new version of the same patch/commit), kindly add following tags | Reported-by: kernel test robot <lkp@xxxxxxxxx> | Closes: https://lore.kernel.org/oe-kbuild-all/202404122206.TkXKhj29-lkp@xxxxxxxxx/ All warnings (new ones prefixed by >>): In file included from arch/riscv/kernel/cpufeature.c:20: In file included from arch/riscv/include/asm/cacheflush.h:9: In file included from include/linux/mm.h:2208: include/linux/vmstat.h:522:36: warning: arithmetic between different enumeration types ('enum node_stat_item' and 'enum lru_list') [-Wenum-enum-conversion] 522 | return node_stat_name(NR_LRU_BASE + lru) + 3; // skip "nr_" | ~~~~~~~~~~~ ^ ~~~ >> arch/riscv/kernel/cpufeature.c:395:4: warning: label followed by a declaration is a C23 extension [-Wc23-extensions] 395 | bool found; | ^ 2 warnings generated. vim +395 arch/riscv/kernel/cpufeature.c 370 371 static void __init riscv_parse_isa_string(unsigned long *this_hwcap, struct riscv_isainfo *isainfo, 372 struct riscv_isainfo *isavendorinfo, unsigned long vendorid, 373 unsigned long *isa2hwcap, const char *isa) 374 { 375 /* 376 * For all possible cpus, we have already validated in 377 * the boot process that they at least contain "rv" and 378 * whichever of "32"/"64" this kernel supports, and so this 379 * section can be skipped. 380 */ 381 isa += 4; 382 383 while (*isa) { 384 const char *ext = isa++; 385 const char *ext_end = isa; 386 bool ext_long = false, ext_err = false; 387 struct riscv_isainfo *selected_isainfo = isainfo; 388 const struct riscv_isa_ext_data *selected_riscv_isa_ext = riscv_isa_ext; 389 size_t selected_riscv_isa_ext_count = riscv_isa_ext_count; 390 unsigned int id_offset = 0; 391 392 switch (*ext) { 393 case 'x': 394 case 'X': > 395 bool found; 396 397 found = get_isa_vendor_ext(vendorid, 398 &selected_riscv_isa_ext, 399 &selected_riscv_isa_ext_count); 400 selected_isainfo = isavendorinfo; 401 id_offset = RISCV_ISA_VENDOR_EXT_BASE; 402 if (!found) { 403 pr_warn("No associated vendor extensions with vendor id: %lx\n", 404 vendorid); 405 for (; *isa && *isa != '_'; ++isa) 406 ; 407 ext_err = true; 408 break; 409 } 410 fallthrough; 411 case 's': 412 /* 413 * Workaround for invalid single-letter 's' & 'u' (QEMU). 414 * No need to set the bit in riscv_isa as 's' & 'u' are 415 * not valid ISA extensions. It works unless the first 416 * multi-letter extension in the ISA string begins with 417 * "Su" and is not prefixed with an underscore. 418 */ 419 if (ext[-1] != '_' && ext[1] == 'u') { 420 ++isa; 421 ext_err = true; 422 break; 423 } 424 fallthrough; 425 case 'S': 426 case 'z': 427 case 'Z': 428 /* 429 * Before attempting to parse the extension itself, we find its end. 430 * As multi-letter extensions must be split from other multi-letter 431 * extensions with an "_", the end of a multi-letter extension will 432 * either be the null character or the "_" at the start of the next 433 * multi-letter extension. 434 * 435 * Next, as the extensions version is currently ignored, we 436 * eliminate that portion. This is done by parsing backwards from 437 * the end of the extension, removing any numbers. This may be a 438 * major or minor number however, so the process is repeated if a 439 * minor number was found. 440 * 441 * ext_end is intended to represent the first character *after* the 442 * name portion of an extension, but will be decremented to the last 443 * character itself while eliminating the extensions version number. 444 * A simple re-increment solves this problem. 445 */ 446 ext_long = true; 447 for (; *isa && *isa != '_'; ++isa) 448 if (unlikely(!isalnum(*isa))) 449 ext_err = true; 450 451 ext_end = isa; 452 if (unlikely(ext_err)) 453 break; 454 455 if (!isdigit(ext_end[-1])) 456 break; 457 458 while (isdigit(*--ext_end)) 459 ; 460 461 if (tolower(ext_end[0]) != 'p' || !isdigit(ext_end[-1])) { 462 ++ext_end; 463 break; 464 } 465 466 while (isdigit(*--ext_end)) 467 ; 468 469 ++ext_end; 470 break; 471 default: 472 /* 473 * Things are a little easier for single-letter extensions, as they 474 * are parsed forwards. 475 * 476 * After checking that our starting position is valid, we need to 477 * ensure that, when isa was incremented at the start of the loop, 478 * that it arrived at the start of the next extension. 479 * 480 * If we are already on a non-digit, there is nothing to do. Either 481 * we have a multi-letter extension's _, or the start of an 482 * extension. 483 * 484 * Otherwise we have found the current extension's major version 485 * number. Parse past it, and a subsequent p/minor version number 486 * if present. The `p` extension must not appear immediately after 487 * a number, so there is no fear of missing it. 488 * 489 */ 490 if (unlikely(!isalpha(*ext))) { 491 ext_err = true; 492 break; 493 } 494 495 if (!isdigit(*isa)) 496 break; 497 498 while (isdigit(*++isa)) 499 ; 500 501 if (tolower(*isa) != 'p') 502 break; 503 504 if (!isdigit(*++isa)) { 505 --isa; 506 break; 507 } 508 509 while (isdigit(*++isa)) 510 ; 511 512 break; 513 } 514 515 /* 516 * The parser expects that at the start of an iteration isa points to the 517 * first character of the next extension. As we stop parsing an extension 518 * on meeting a non-alphanumeric character, an extra increment is needed 519 * where the succeeding extension is a multi-letter prefixed with an "_". 520 */ 521 if (*isa == '_') 522 ++isa; 523 524 if (unlikely(ext_err)) 525 continue; 526 if (!ext_long) { 527 int nr = tolower(*ext) - 'a'; 528 529 if (riscv_isa_extension_check(nr)) { 530 *this_hwcap |= isa2hwcap[nr]; 531 set_bit(nr, isainfo->isa); 532 } 533 } else { 534 for (int i = 0; i < selected_riscv_isa_ext_count; i++) 535 match_isa_ext(&selected_riscv_isa_ext[i], ext, 536 ext_end, selected_isainfo, 537 id_offset); 538 } 539 } 540 } 541 -- 0-DAY CI Kernel Test Service https://github.com/intel/lkp-tests/wiki