Hi Thomas, kernel test robot noticed the following build errors: [auto build test ERROR on staging/staging-testing] [also build test ERROR on staging/staging-next staging/staging-linus drm/drm-next drm-exynos/exynos-drm-next linus/master v6.13-rc2 next-20241211] [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/Thomas-Zimmermann/fbdev-Fix-recursive-dependencies-wrt-BACKLIGHT_CLASS_DEVICE/20241210-222618 base: staging/staging-testing patch link: https://lore.kernel.org/r/20241210142329.660801-2-tzimmermann%40suse.de patch subject: [PATCH 1/3] fbdev: Fix recursive dependencies wrt BACKLIGHT_CLASS_DEVICE config: loongarch-defconfig (https://download.01.org/0day-ci/archive/20241211/202412112135.pzFeIjEo-lkp@xxxxxxxxx/config) compiler: loongarch64-linux-gcc (GCC) 14.2.0 reproduce (this is a W=1 build): (https://download.01.org/0day-ci/archive/20241211/202412112135.pzFeIjEo-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/202412112135.pzFeIjEo-lkp@xxxxxxxxx/ All errors (new ones prefixed by >>): loongarch64-linux-ld: drivers/video/fbdev/aty/radeon_backlight.o: in function `radeonfb_bl_init': >> radeon_backlight.c:(.text+0x424): undefined reference to `backlight_device_register' loongarch64-linux-ld: drivers/video/fbdev/aty/radeon_backlight.o: in function `radeonfb_bl_exit': >> radeon_backlight.c:(.text+0x560): undefined reference to `backlight_device_unregister' -- 0-DAY CI Kernel Test Service https://github.com/intel/lkp-tests/wiki