CC: [email protected] BCC: [email protected] CC: "GNU/Weeb Mailing List" <[email protected]> CC: [email protected] TO: Borislav Petkov <[email protected]> CC: Kees Cook <[email protected]>
tree: https://github.com/ammarfaizi2/linux-block bp/bp/rc0+ head: 2d784fc7295963360594f3de64446aa32841c694 commit: c3b9dcd01973935375ca9d0c67044bea7333d4ef [6/11] x86/cpu: Allow feature bit names from /proc/cpuinfo in clearcpuid= :::::: branch date: 4 hours ago :::::: commit date: 5 hours ago config: i386-randconfig-m021-20220328 (https://download.01.org/0day-ci/archive/20220329/[email protected]/config) compiler: gcc-9 (Ubuntu 9.4.0-1ubuntu1~20.04.1) 9.4.0 If you fix the issue, kindly add following tag as appropriate Reported-by: kernel test robot <[email protected]> Reported-by: Dan Carpenter <[email protected]> smatch warnings: arch/x86/kernel/cpu/common.c:1418 cpu_parse_early_param() warn: potential spectre issue 'x86_cap_flags' [w] (local cap) vim +/x86_cap_flags +1418 arch/x86/kernel/cpu/common.c 1ef5423a55c2ac Mike Hommey 2020-09-22 1385 1ef5423a55c2ac Mike Hommey 2020-09-22 1386 if (cmdline_find_option_bool(boot_command_line, "noxsave")) 1ef5423a55c2ac Mike Hommey 2020-09-22 1387 setup_clear_cpu_cap(X86_FEATURE_XSAVE); 1ef5423a55c2ac Mike Hommey 2020-09-22 1388 1ef5423a55c2ac Mike Hommey 2020-09-22 1389 if (cmdline_find_option_bool(boot_command_line, "noxsaveopt")) 1ef5423a55c2ac Mike Hommey 2020-09-22 1390 setup_clear_cpu_cap(X86_FEATURE_XSAVEOPT); 1ef5423a55c2ac Mike Hommey 2020-09-22 1391 1ef5423a55c2ac Mike Hommey 2020-09-22 1392 if (cmdline_find_option_bool(boot_command_line, "noxsaves")) 1ef5423a55c2ac Mike Hommey 2020-09-22 1393 setup_clear_cpu_cap(X86_FEATURE_XSAVES); 1ef5423a55c2ac Mike Hommey 2020-09-22 1394 1ef5423a55c2ac Mike Hommey 2020-09-22 1395 arglen = cmdline_find_option(boot_command_line, "clearcpuid", arg, sizeof(arg)); 1ef5423a55c2ac Mike Hommey 2020-09-22 1396 if (arglen <= 0) 1ef5423a55c2ac Mike Hommey 2020-09-22 1397 return; 1ef5423a55c2ac Mike Hommey 2020-09-22 1398 1ef5423a55c2ac Mike Hommey 2020-09-22 1399 pr_info("Clearing CPUID bits:"); 1ef5423a55c2ac Mike Hommey 2020-09-22 1400 c3b9dcd0197393 Borislav Petkov 2022-01-27 1401 while (argptr) { c3b9dcd0197393 Borislav Petkov 2022-01-27 1402 bool found __maybe_unused = false; c3b9dcd0197393 Borislav Petkov 2022-01-27 1403 unsigned int bit; c3b9dcd0197393 Borislav Petkov 2022-01-27 1404 c3b9dcd0197393 Borislav Petkov 2022-01-27 1405 opt = strsep(&argptr, ","); c3b9dcd0197393 Borislav Petkov 2022-01-27 1406 c3b9dcd0197393 Borislav Petkov 2022-01-27 1407 /* c3b9dcd0197393 Borislav Petkov 2022-01-27 1408 * Handle naked numbers first for feature flags which don't c3b9dcd0197393 Borislav Petkov 2022-01-27 1409 * have names. c3b9dcd0197393 Borislav Petkov 2022-01-27 1410 */ c3b9dcd0197393 Borislav Petkov 2022-01-27 1411 if (!kstrtouint(opt, 10, &bit)) { c3b9dcd0197393 Borislav Petkov 2022-01-27 1412 if (bit < NCAPINTS * 32) { 1ef5423a55c2ac Mike Hommey 2020-09-22 1413 c3b9dcd0197393 Borislav Petkov 2022-01-27 1414 /* empty-string, i.e., ""-defined feature flags */ c3b9dcd0197393 Borislav Petkov 2022-01-27 1415 if (!x86_cap_flags[bit]) c3b9dcd0197393 Borislav Petkov 2022-01-27 1416 pr_cont(" " X86_CAP_FMT_NUM, x86_cap_flag_num(bit)); c3b9dcd0197393 Borislav Petkov 2022-01-27 1417 else 1ef5423a55c2ac Mike Hommey 2020-09-22 @1418 pr_cont(" " X86_CAP_FMT, x86_cap_flag(bit)); c3b9dcd0197393 Borislav Petkov 2022-01-27 1419 c3b9dcd0197393 Borislav Petkov 2022-01-27 1420 setup_clear_cpu_cap(bit); c3b9dcd0197393 Borislav Petkov 2022-01-27 1421 taint++; c3b9dcd0197393 Borislav Petkov 2022-01-27 1422 } c3b9dcd0197393 Borislav Petkov 2022-01-27 1423 /* c3b9dcd0197393 Borislav Petkov 2022-01-27 1424 * The assumption is that there are no feature names with only c3b9dcd0197393 Borislav Petkov 2022-01-27 1425 * numbers in the name thus go to the next argument. c3b9dcd0197393 Borislav Petkov 2022-01-27 1426 */ c3b9dcd0197393 Borislav Petkov 2022-01-27 1427 continue; c3b9dcd0197393 Borislav Petkov 2022-01-27 1428 } c3b9dcd0197393 Borislav Petkov 2022-01-27 1429 :::::: The code at line 1418 was first introduced by commit :::::: 1ef5423a55c2ac6f1361811efe75b6e46d1023ed x86/fpu: Handle FPU-related and clearcpuid command line arguments earlier :::::: TO: Mike Hommey <[email protected]> :::::: CC: Borislav Petkov <[email protected]> -- 0-DAY CI Kernel Test Service https://01.org/lkp _______________________________________________ kbuild mailing list -- [email protected] To unsubscribe send an email to [email protected]
