Hi Tzu-En, FYI, the error/warning still remains. tree: https://git.kernel.org/pub/scm/linux/kernel/git/next/linux-next.git master head: 148fdf990dee4efd23c1114811b205de9c966680 commit: 0fbc2f0f34cc57e8d6076631733e0095ac031995 [11074/14813] rtw88: add dump firmware fifo support config: arm64-randconfig-r036-20201012 (attached as .config) compiler: clang version 12.0.0 (https://github.com/llvm/llvm-project 9e72d3eaf38f217698f72cb8fdc969a6e72dad3a) 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://git.kernel.org/pub/scm/linux/kernel/git/next/linux-next.git/commi... git remote add linux-next https://git.kernel.org/pub/scm/linux/kernel/git/next/linux-next.git git fetch --no-tags linux-next master git checkout 0fbc2f0f34cc57e8d6076631733e0095ac031995 # 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 >>): if (!rtwdev->chip->fw_fifo_addr) { ~~~~~~~~~~~~~~~^~~~~~~~~~~~ 1 warning generated. vim +1485 drivers/net/wireless/realtek/rtw88/fw.c 1481 1482 int rtw_fw_dump_fifo(struct rtw_dev *rtwdev, u8 fifo_sel, u32 addr, u32 size, 1483 u32 *buffer) 1484 { 1486 rtw_dbg(rtwdev, RTW_DBG_FW, "chip not support dump fw fifo\n"); 1487 return -ENOTSUPP; 1488 } 1489 1490 if (size == 0 || !buffer) 1491 return -EINVAL; 1492 1493 if (size & 0x3) { 1494 rtw_dbg(rtwdev, RTW_DBG_FW, "not 4byte alignment\n"); 1495 return -EINVAL; 1496 } 1497 1498 if (!rtw_fw_dump_check_size(rtwdev, fifo_sel, addr, size)) { 1499 rtw_dbg(rtwdev, RTW_DBG_FW, "fw fifo dump size overflow\n"); 1500 return -EINVAL; 1501 } 1502 1503 rtw_fw_read_fifo(rtwdev, fifo_sel, addr, size, buffer); 1504 1505 return 0; 1506 } 1507 --- 0-DAY CI Kernel Test Service, Intel Corporation https://lists.01.org/hyperkitty/list/kbuild-all@lists.01.org