Hi Tony, I love your patch! Perhaps something to improve: [auto build test WARNING on tty/tty-testing] [also build test WARNING on tty/tty-next tty/tty-linus rafael-pm/linux-next usb/usb-testing usb/usb-next usb/usb-linus linus/master v6.3-rc1 next-20230309] [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/Tony-Lindgren/serial-core-Start-managing-serial-controllers-to-enable-runtime-PM/20230309-170149 base: https://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty.git tty-testing patch link: https://lore.kernel.org/r/20230309085713.57700-1-tony%40atomide.com patch subject: [PATCH v6 1/1] serial: core: Start managing serial controllers to enable runtime PM config: i386-allnoconfig (https://download.01.org/0day-ci/archive/20230310/202303100833.lk1UVhcR-lkp@xxxxxxxxx/config) compiler: clang version 14.0.6 (https://github.com/llvm/llvm-project f28c006a5895fc0e329fe15fead81e37457cb1d1) reproduce (this is a W=1 build): wget https://raw.githubusercontent.com/intel/lkp-tests/master/sbin/make.cross -O ~/bin/make.cross chmod +x ~/bin/make.cross # https://github.com/intel-lab-lkp/linux/commit/08f76f28e32bcd3c093e4af349b0e1b60328395e git remote add linux-review https://github.com/intel-lab-lkp/linux git fetch --no-tags linux-review Tony-Lindgren/serial-core-Start-managing-serial-controllers-to-enable-runtime-PM/20230309-170149 git checkout 08f76f28e32bcd3c093e4af349b0e1b60328395e # save the config file mkdir build_dir && cp config build_dir/.config COMPILER_INSTALL_PATH=$HOME/0day COMPILER=clang make.cross W=1 O=build_dir ARCH=i386 olddefconfig COMPILER_INSTALL_PATH=$HOME/0day COMPILER=clang make.cross W=1 O=build_dir ARCH=i386 SHELL=/bin/bash drivers/tty/serial/ If you fix the issue, kindly add following tag where applicable | Reported-by: kernel test robot <lkp@xxxxxxxxx> | Link: https://lore.kernel.org/oe-kbuild-all/202303100833.lk1UVhcR-lkp@xxxxxxxxx/ All warnings (new ones prefixed by >>): >> drivers/tty/serial/serial_ctrl.c:17:34: warning: unused variable 'serial_ctrl_pm' [-Wunused-const-variable] static DEFINE_RUNTIME_DEV_PM_OPS(serial_ctrl_pm, NULL, NULL, NULL); ^ 1 warning generated. vim +/serial_ctrl_pm +17 drivers/tty/serial/serial_ctrl.c 16 > 17 static DEFINE_RUNTIME_DEV_PM_OPS(serial_ctrl_pm, NULL, NULL, NULL); 18 -- 0-DAY CI Kernel Test Service https://github.com/intel/lkp-tests