tree: https://git.kernel.org/pub/scm/linux/kernel/git/mcgrof/linux-next.git 20210427-sysfs-fix-races-v4 head: 177cab73f0f242ce77398095d9c54d76d7fa46df commit: 177cab73f0f242ce77398095d9c54d76d7fa46df [3/3] drivers/base/core: refcount kobject and bus on device attribute read / store config: powerpc-randconfig-r002-20210618 (attached as .config) compiler: clang version 13.0.0 (https://github.com/llvm/llvm-project 64720f57bea6a6bf033feef4a5751ab9c0c3b401) 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 # install powerpc cross compiling tool for clang build # apt-get install binutils-powerpc-linux-gnu # https://git.kernel.org/pub/scm/linux/kernel/git/mcgrof/linux-next.git/com... git remote add mcgrof-next https://git.kernel.org/pub/scm/linux/kernel/git/mcgrof/linux-next.git git fetch --no-tags mcgrof-next 20210427-sysfs-fix-races-v4 git checkout 177cab73f0f242ce77398095d9c54d76d7fa46df # save the attached .config to linux build tree COMPILER_INSTALL_PATH=$HOME/0day COMPILER=clang make.cross ARCH=powerpc If you fix the issue, kindly add following tag as appropriate Reported-by: kernel test robot <lkp(a)intel.com&gt; All warnings (new ones prefixed by >>): In file included from drivers/base/bus.c:11: In file included from include/linux/async.h:12: In file included from include/linux/list.h:9: In file included from include/linux/kernel.h:12: In file included from include/linux/bitops.h:32: In file included from arch/powerpc/include/asm/bitops.h:62: arch/powerpc/include/asm/barrier.h:49:9: warning: '__lwsync' macro redefined [-Wmacro-redefined] #define __lwsync() __asm__ __volatile__ (stringify_in_c(LWSYNC) : : :"memory") ^ <built-in>:309:9: note: previous definition is here #define __lwsync __builtin_ppc_lwsync ^ struct bus_type *bus_get(struct bus_type *bus) ^ drivers/base/bus.c:42:1: note: declare 'static' if the function is not intended to be used outside of this translation unit struct bus_type *bus_get(struct bus_type *bus) ^ static void bus_put(struct bus_type *bus) ^ drivers/base/bus.c:51:1: note: declare 'static' if the function is not intended to be used outside of this translation unit void bus_put(struct bus_type *bus) ^ static 3 warnings generated. vim +/bus_get +42 drivers/base/bus.c 34 35 #define DRIVER_ATTR_IGNORE_LOCKDEP(_name, _mode, _show, _store) \ 36 struct driver_attribute driver_attr_##_name = \ 37 __ATTR_IGNORE_LOCKDEP(_name, _mode, _show, _store) 38 39 static int __must_check bus_rescan_devices_helper(struct device *dev, 40 void *data); 41 43 { 44 if (bus) { 45 kset_get(&bus->p->subsys); 46 return bus; 47 } 48 return NULL; 49 } 50 52 { 53 if (bus) 54 kset_put(&bus->p->subsys); 55 } 56 --- 0-DAY CI Kernel Test Service, Intel Corporation https://lists.01.org/hyperkitty/list/kbuild-all@lists.01.org