Hi Victor, Thank you for the patch! Yet something to improve: [auto build test ERROR on net-next/master] url: https://github.com/0day-ci/linux/commits/Victor-Stewart/udp-allow-UDP-cms... base: https://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next.git 3db1a3fa98808aa90f95ec3e0fa2fc7abf28f5c9 config: riscv-randconfig-r031-20201216 (attached as .config) compiler: clang version 12.0.0 (https://github.com/llvm/llvm-project 71601d2ac9954cb59c443cb3ae442cb106df35d4) 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 riscv cross compiling tool for clang build # apt-get install binutils-riscv64-linux-gnu # https://github.com/0day-ci/linux/commit/6cce2a0155c3ee2a1550cb3d5e434cc85... git remote add linux-review https://github.com/0day-ci/linux git fetch --no-tags linux-review Victor-Stewart/udp-allow-UDP-cmsghdrs-through-io_uring/20201217-020451 git checkout 6cce2a0155c3ee2a1550cb3d5e434cc85f055a60 # save the attached .config to linux build tree COMPILER_INSTALL_PATH=$HOME/0day COMPILER=clang make.cross ARCH=riscv If you fix the issue, kindly add following tag as appropriate Reported-by: kernel test robot <lkp(a)intel.com&gt; All errors (new ones prefixed by >>): /tmp/leds-blinkm-655475.s: Assembler messages: /tmp/leds-blinkm-655475.s:750: Error: unrecognized opcode `zext.b a2,s2' /tmp/leds-blinkm-655475.s:833: Error: unrecognized opcode `zext.b a2,s2' clang-12: error: assembler command failed with exit code 1 (use -v to see invocation) --- 0-DAY CI Kernel Test Service, Intel Corporation https://lists.01.org/hyperkitty/list/kbuild-all@lists.01.org