tree: https://github.com/lunn/linux.git v5.6-rc5-net-next-cable-test head: b31a0e1be47110cf03960f7d8514f9f69ad67430 commit: fdd754945bdb1bdf797cb646fe9a7406fc29ed62 [8/22] net: ethtool: netlink: Add support for triggering a cable test config: csky-defconfig (attached as .config) compiler: csky-linux-gcc (GCC) 9.3.0 reproduce: wget https://raw.githubusercontent.com/intel/lkp-tests/master/sbin/make.cross -O ~/bin/make.cross chmod +x ~/bin/make.cross git checkout fdd754945bdb1bdf797cb646fe9a7406fc29ed62 # save the attached .config to linux build tree GCC_VERSION=9.3.0 make.cross ARCH=csky If you fix the issue, kindly add following tag as appropriate Reported-by: kbuild test robot <lkp(a)intel.com&gt; All errors (new ones prefixed by >>): csky-linux-ld: drivers/net/phy/mdio_bus.o: in function `__mdiobus_register': csky-linux-ld: drivers/net/phy/mdio_bus.o: in function `$d': mdio_bus.c:(.text+0x6e0): undefined reference to `mdiobus_setup_mdiodev_from_board_info' csky-linux-ld: drivers/net/phy/fixed_phy.o: in function `fixed_mdio_read': csky-linux-ld: drivers/net/phy/fixed_phy.o: in function `$d': fixed_phy.c:(.text+0x210): undefined reference to `swphy_read_reg' csky-linux-ld: drivers/net/phy/fixed_phy.o: in function `__fixed_phy_register.part.0': csky-linux-ld: drivers/net/phy/fixed_phy.o: in function `fixed_phy_add': fixed_phy.c:(.text+0x446): undefined reference to `swphy_validate_state' csky-linux-ld: drivers/net/phy/fixed_phy.o: in function `$d': fixed_phy.c:(.text+0x47c): undefined reference to `swphy_validate_state' --- 0-DAY CI Kernel Test Service, Intel Corporation https://lists.01.org/hyperkitty/list/kbuild-all@lists.01.org