Re: [PATCH v2] x86/tsc: Disable clocksource watchdog for TSC on recent UV

From: kernel test robot
Date: Fri Aug 08 2025 - 02:22:14 EST


Hi Dimitri,

kernel test robot noticed the following build errors:

[auto build test ERROR on tip/x86/core]
[also build test ERROR on tip/master linus/master v6.16 next-20250807]
[cannot apply to tip/auto-latest]
[If your patch is applied to the wrong git tree, kindly drop us a note.
And when submitting patch, we suggest to use '--base' as documented in
https://git-scm.com/docs/git-format-patch#_base_tree_information]

url: https://github.com/intel-lab-lkp/linux/commits/Dimitri-Sivanich/x86-tsc-Disable-clocksource-watchdog-for-TSC-on-recent-UV/20250806-120227
base: tip/x86/core
patch link: https://lore.kernel.org/r/aJH9ke0k0HnL8g6h%40hpe.com
patch subject: [PATCH v2] x86/tsc: Disable clocksource watchdog for TSC on recent UV
config: i386-randconfig-011-20250808 (https://download.01.org/0day-ci/archive/20250808/202508081446.3ZnRCG1T-lkp@xxxxxxxxx/config)
compiler: clang version 20.1.8 (https://github.com/llvm/llvm-project 87f0227cb60147a26a1eeb4fb06e3b505e9c7261)
reproduce (this is a W=1 build): (https://download.01.org/0day-ci/archive/20250808/202508081446.3ZnRCG1T-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/202508081446.3ZnRCG1T-lkp@xxxxxxxxx/

All errors (new ones prefixed by >>):

>> arch/x86/kernel/tsc.c:1264:39: error: call to undeclared function 'is_uvy_hub'; ISO C99 and later do not support implicit function declarations [-Wimplicit-function-declaration]
1264 | (topology_max_packages() <= 4 || is_uvy_hub()))
| ^
arch/x86/kernel/tsc.c:1517:6: error: call to undeclared function 'is_early_uv_system'; ISO C99 and later do not support implicit function declarations [-Wimplicit-function-declaration]
1517 | if (is_early_uv_system())
| ^
2 errors generated.


vim +/is_uvy_hub +1264 arch/x86/kernel/tsc.c

1235
1236 static void __init check_system_tsc_reliable(void)
1237 {
1238 #if defined(CONFIG_MGEODEGX1) || defined(CONFIG_MGEODE_LX) || defined(CONFIG_X86_GENERIC)
1239 if (is_geode_lx()) {
1240 /* RTSC counts during suspend */
1241 #define RTSC_SUSP 0x100
1242 unsigned long res_low, res_high;
1243
1244 rdmsr_safe(MSR_GEODE_BUSCONT_CONF0, &res_low, &res_high);
1245 /* Geode_LX - the OLPC CPU has a very reliable TSC */
1246 if (res_low & RTSC_SUSP)
1247 tsc_clocksource_reliable = 1;
1248 }
1249 #endif
1250 if (boot_cpu_has(X86_FEATURE_TSC_RELIABLE))
1251 tsc_clocksource_reliable = 1;
1252
1253 /*
1254 * Disable the clocksource watchdog when the system has:
1255 * - TSC running at constant frequency
1256 * - TSC which does not stop in C-States
1257 * - the TSC_ADJUST register which allows to detect even minimal
1258 * modifications
1259 * - not more than four packages
1260 */
1261 if (boot_cpu_has(X86_FEATURE_CONSTANT_TSC) &&
1262 boot_cpu_has(X86_FEATURE_NONSTOP_TSC) &&
1263 boot_cpu_has(X86_FEATURE_TSC_ADJUST) &&
> 1264 (topology_max_packages() <= 4 || is_uvy_hub()))
1265 tsc_disable_clocksource_watchdog();
1266 }
1267

--
0-DAY CI Kernel Test Service
https://github.com/intel/lkp-tests/wiki