Hi Naohiro, First bad commit (maybe != root cause): tree: https://github.com/kdave/btrfs-devel.git ext/aota/zoned-7 head: 17046312f8c0a16a96b4b3a145f4b30be84e6ede commit: d7a064645672c0cb922ca0bc60c687d22f0c1fa4 [132/162] btrfs: implement log-structured superblock for ZONED mode config: sh-allmodconfig (attached as .config) compiler: sh4-linux-gcc (GCC) 9.3.0 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 git checkout d7a064645672c0cb922ca0bc60c687d22f0c1fa4 # save the attached .config to linux build tree COMPILER_INSTALL_PATH=$HOME/0day COMPILER=gcc-9.3.0 make.cross ARCH=sh 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 >>, old ones prefixed by <<): ERROR: modpost: "__delay" [drivers/net/phy/mdio-cavium.ko] undefined! --- 0-DAY CI Kernel Test Service, Intel Corporation https://lists.01.org/hyperkitty/list/kbuild-all@lists.01.org