Hi John, I love your patch! Perhaps something to improve: [auto build test WARNING on next-20210528] url: https://github.com/0day-ci/linux/commits/John-Ogness/introduce-printk-cpu-lock/20210601-013122 base: 3e029760e6f8ce90c122c267a039ae73b3f1f5a4 config: m68k-allmodconfig (attached as .config) compiler: m68k-linux-gcc (GCC) 9.3.0 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/0day-ci/linux/commit/528abf3d0ab80471d02f4f16cbe97b2eaa918a11 git remote add linux-review https://github.com/0day-ci/linux git fetch --no-tags linux-review John-Ogness/introduce-printk-cpu-lock/20210601-013122 git checkout 528abf3d0ab80471d02f4f16cbe97b2eaa918a11 # save the attached .config to linux build tree COMPILER_INSTALL_PATH=$HOME/0day COMPILER=gcc-9.3.0 make.cross ARCH=m68k If you fix the issue, kindly add following tag as appropriate Reported-by: kernel test robot All warnings (new ones prefixed by >>): lib/dump_stack.c:97: warning: Function parameter or member 'log_lvl' not described in 'dump_stack_lvl' >> lib/dump_stack.c:97: warning: expecting prototype for dump_stack(). Prototype was for dump_stack_lvl() instead vim +97 lib/dump_stack.c ^1da177e4c3f41 Linus Torvalds 2005-04-16 90 196779b9b4ce19 Tejun Heo 2013-04-30 91 /** 196779b9b4ce19 Tejun Heo 2013-04-30 92 * dump_stack - dump the current task information and its stack trace 196779b9b4ce19 Tejun Heo 2013-04-30 93 * 196779b9b4ce19 Tejun Heo 2013-04-30 94 * Architectures can override this implementation by implementing its own. 196779b9b4ce19 Tejun Heo 2013-04-30 95 */ d542aa86de8ad0 Alexander Potapenko 2021-05-26 96 asmlinkage __visible void dump_stack_lvl(const char *log_lvl) ^1da177e4c3f41 Linus Torvalds 2005-04-16 @97 { 528abf3d0ab804 John Ogness 2021-05-31 98 unsigned int cpu_store; d7ce36924344ac Eric Dumazet 2016-02-05 99 unsigned long flags; b58d977432c80e Alex Thorlton 2013-07-03 100 528abf3d0ab804 John Ogness 2021-05-31 101 printk_cpu_lock(&cpu_store, &flags); d542aa86de8ad0 Alexander Potapenko 2021-05-26 102 __dump_stack(log_lvl); 528abf3d0ab804 John Ogness 2021-05-31 103 printk_cpu_unlock(cpu_store, flags); b58d977432c80e Alex Thorlton 2013-07-03 104 } d542aa86de8ad0 Alexander Potapenko 2021-05-26 105 EXPORT_SYMBOL(dump_stack_lvl); d542aa86de8ad0 Alexander Potapenko 2021-05-26 106 --- 0-DAY CI Kernel Test Service, Intel Corporation https://lists.01.org/hyperkitty/list/kbuild-all@lists.01.org