Hi Dmitry, I love your patch! Perhaps something to improve: [auto build test WARNING on kees/for-next/pstore] [also build test WARNING on linus/master jeyu/modules-next v5.16-rc8 next-20211224] [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/Dmitry-Torokhov/module-add-in-kernel-support-for-decompressing/20220104-133017 base: https://git.kernel.org/pub/scm/linux/kernel/git/kees/linux.git for-next/pstore config: um-i386_defconfig (https://download.01.org/0day-ci/archive/20220104/202201041739.pqEpumnU-lkp@intel.com/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/dee0e9ca58491575033bc7911dd4fe8f7cea40e4 git remote add linux-review https://github.com/0day-ci/linux git fetch --no-tags linux-review Dmitry-Torokhov/module-add-in-kernel-support-for-decompressing/20220104-133017 git checkout dee0e9ca58491575033bc7911dd4fe8f7cea40e4 # save the config file to linux build tree mkdir build_dir make W=1 O=build_dir ARCH=um SUBARCH=i386 SHELL=/bin/bash If you fix the issue, kindly add following tag as appropriate Reported-by: kernel test robot All warnings (new ones prefixed by >>): In file included from kernel/module.c:61: >> kernel/module-internal.h:42:5: warning: no previous prototype for 'module_decompress' [-Wmissing-prototypes] 42 | int module_decompress(struct load_info *info, const void *buf, size_t size) | ^~~~~~~~~~~~~~~~~ >> kernel/module-internal.h:46:6: warning: no previous prototype for 'module_decompress_cleanup' [-Wmissing-prototypes] 46 | void module_decompress_cleanup(struct load_info *info) | ^~~~~~~~~~~~~~~~~~~~~~~~~ vim +/module_decompress +42 kernel/module-internal.h 37 38 #ifdef CONFIG_MODULE_DECOMPRESS 39 int module_decompress(struct load_info *info, const void *buf, size_t size); 40 void module_decompress_cleanup(struct load_info *info); 41 #else > 42 int module_decompress(struct load_info *info, const void *buf, size_t size) 43 { 44 return -EOPNOTSUPP; 45 } > 46 void module_decompress_cleanup(struct load_info *info) --- 0-DAY CI Kernel Test Service, Intel Corporation https://lists.01.org/hyperkitty/list/kbuild-all@lists.01.org