Hi Zhi, I love your patch! Perhaps something to improve: [auto build test WARNING on drm-tip/drm-tip] [also build test WARNING on next-20220127] [cannot apply to drm-intel/for-linux-next hch-configfs/for-next v5.17-rc1] [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/Zhi-Wang/i915-gvt-Introduce-the-mmio_table-c-to-support-VFIO-new-mdev-API/20220127-200727 base: git://anongit.freedesktop.org/drm/drm-tip drm-tip config: x86_64-randconfig-a005 (https://download.01.org/0day-ci/archive/20220128/202201280121.YX5gboDp-lkp@xxxxxxxxx/config) compiler: clang version 14.0.0 (https://github.com/llvm/llvm-project f32dccb9a43b02ce4e540d6ba5dbbdb188f2dc7d) 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/533f92651a7a56481a053f1e04dc5a5ec024ffb9 git remote add linux-review https://github.com/0day-ci/linux git fetch --no-tags linux-review Zhi-Wang/i915-gvt-Introduce-the-mmio_table-c-to-support-VFIO-new-mdev-API/20220127-200727 git checkout 533f92651a7a56481a053f1e04dc5a5ec024ffb9 # save the config file to linux build tree mkdir build_dir COMPILER_INSTALL_PATH=$HOME/0day COMPILER=clang make.cross W=1 O=build_dir ARCH=x86_64 SHELL=/bin/bash drivers/gpu/ If you fix the issue, kindly add following tag as appropriate Reported-by: kernel test robot <lkp@xxxxxxxxx> All warnings (new ones prefixed by >>): >> drivers/gpu/drm/i915/gvt/handlers.c:45:6: warning: no previous prototype for function 'intel_gvt_match_device' [-Wmissing-prototypes] bool intel_gvt_match_device(struct intel_gvt *gvt, ^ drivers/gpu/drm/i915/gvt/handlers.c:45:1: note: declare 'static' if the function is not intended to be used outside of this translation unit bool intel_gvt_match_device(struct intel_gvt *gvt, ^ static 1 warning generated. vim +/intel_gvt_match_device +45 drivers/gpu/drm/i915/gvt/handlers.c 12d14cc43b3470 Zhi Wang 2016-08-30 44 12d14cc43b3470 Zhi Wang 2016-08-30 @45 bool intel_gvt_match_device(struct intel_gvt *gvt, 12d14cc43b3470 Zhi Wang 2016-08-30 46 unsigned long device) 12d14cc43b3470 Zhi Wang 2016-08-30 47 { 533f92651a7a56 Zhi Wang 2022-01-27 48 return intel_gvt_get_device_type(gvt->gt->i915) & device; 12d14cc43b3470 Zhi Wang 2016-08-30 49 } 12d14cc43b3470 Zhi Wang 2016-08-30 50 --- 0-DAY CI Kernel Test Service, Intel Corporation https://lists.01.org/hyperkitty/list/kbuild-all@xxxxxxxxxxxx