Hi Ashish, Thank you for the patch! Perhaps something to improve: [auto build test WARNING on tip/x86/core] [also build test WARNING on tip/x86/mm hch-configfs/for-next v5.10-rc4 next-20201117] [cannot apply to swiotlb/linux-next] [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/Ashish-Kalra/swiotlb-Adjust-SWIO... base: https://git.kernel.org/pub/scm/linux/kernel/git/tip/tip.git 238c91115cd05c71447ea071624a4c9fe661f970 config: arm64-randconfig-r036-20201117 (attached as .config) compiler: clang version 12.0.0 (https://github.com/llvm/llvm-project ace9653c11c6308401dcda2e8b26bf97e6e66e30) 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 arm64 cross compiling tool for clang build # apt-get install binutils-aarch64-linux-gnu # https://github.com/0day-ci/linux/commit/ec17437123f45040f2139e36122a4021f... git remote add linux-review https://github.com/0day-ci/linux git fetch --no-tags linux-review Ashish-Kalra/swiotlb-Adjust-SWIOTBL-bounce-buffer-size-for-SEV-guests/20201118-020049 git checkout ec17437123f45040f2139e36122a4021f1fd3b07 # save the attached .config to linux build tree COMPILER_INSTALL_PATH=$HOME/0day COMPILER=clang make.cross ARCH=arm64 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 >>): unsigned long __init __weak arch_swiotlb_adjust(unsigned long size) ^ kernel/dma/swiotlb.c:166:1: note: declare 'static' if the function is not intended to be used outside of this translation unit unsigned long __init __weak arch_swiotlb_adjust(unsigned long size) ^ static kernel/dma/swiotlb.c:305:1: warning: no previous prototype for function 'swiotlb_late_init_with_default_size' [-Wmissing-prototypes] swiotlb_late_init_with_default_size(size_t default_size) ^ kernel/dma/swiotlb.c:304:1: note: declare 'static' if the function is not intended to be used outside of this translation unit int ^ static 2 warnings generated. vim +/arch_swiotlb_adjust +166 kernel/dma/swiotlb.c 165 167 { 168 return 0; 169 } 170 --- 0-DAY CI Kernel Test Service, Intel Corporation https://lists.01.org/hyperkitty/list/kbuild-all@lists.01.org