Hi Srinivas, I love your patch! Yet something to improve: [auto build test ERROR on rafael-pm/linux-next] [also build test ERROR on linux/master linus/master v5.16 next-20220114] [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] url: https://github.com/0day-ci/linux/commits/Srinivas-Pandruvada/ACPI-fan-Properly-handle-fine-grain-control/20220114-064818 base: https://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm.git linux-next config: i386-randconfig-a003 (https://download.01.org/0day-ci/archive/20220114/202201141519.esDIoL2I-lkp@xxxxxxxxx/config) compiler: gcc-9 (Debian 9.3.0-22) 9.3.0 reproduce (this is a W=1 build): # https://github.com/0day-ci/linux/commit/f30ef71d0435cd8735ee418eeb0bfc71a58a4554 git remote add linux-review https://github.com/0day-ci/linux git fetch --no-tags linux-review Srinivas-Pandruvada/ACPI-fan-Properly-handle-fine-grain-control/20220114-064818 git checkout f30ef71d0435cd8735ee418eeb0bfc71a58a4554 # save the config file to linux build tree mkdir build_dir make W=1 O=build_dir ARCH=i386 SHELL=/bin/bash If you fix the issue, kindly add following tag as appropriate Reported-by: kernel test robot <lkp@xxxxxxxxx> All errors (new ones prefixed by >>): ld: drivers/acpi/fan.o: in function `fan_get_max_state': >> drivers/acpi/fan.c:100: undefined reference to `__udivdi3' ld: drivers/acpi/fan.o: in function `fan_set_state_acpi4': drivers/acpi/fan.c:222: undefined reference to `__udivdi3' ld: drivers/acpi/fan.o: in function `fan_get_state_acpi4': drivers/acpi/fan.c:160: undefined reference to `__udivdi3' vim +100 drivers/acpi/fan.c 91 92 /* thermal cooling device callbacks */ 93 static int fan_get_max_state(struct thermal_cooling_device *cdev, unsigned long 94 *state) 95 { 96 struct acpi_device *device = cdev->devdata; 97 struct acpi_fan *fan = acpi_driver_data(device); 98 99 if (fan->fif.fine_grain_ctrl) > 100 *state = 100 / fan->fif.step_size; 101 else if (fan->acpi4) 102 *state = fan->fps_count - 1; 103 else 104 *state = 1; 105 106 return 0; 107 } 108 --- 0-DAY CI Kernel Test Service, Intel Corporation https://lists.01.org/hyperkitty/list/kbuild-all@xxxxxxxxxxxx