tree: https://git.kernel.org/pub/scm/linux/kernel/git/next/linux-next.git master head: 860461e4fcaa76200d2d1a53523e0ff7be92e6e8 commit: 2fa4e4b799e191530edbae4b96b85d4486e55053 [3012/8629] net: pcs: Move XPCS into new PCS subdirectory config: h8300-randconfig-r011-20200917 (attached as .config) compiler: h8300-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 2fa4e4b799e191530edbae4b96b85d4486e55053 # save the attached .config to linux build tree COMPILER_INSTALL_PATH=$HOME/0day COMPILER=gcc-9.3.0 make.cross ARCH=h8300 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 >>): h8300-linux-ld: drivers/net/phy/mdio_devres.o: in function `devm_mdiobus_free': drivers/net/phy/mdio_devres.c:16: undefined reference to `mdiobus_free' h8300-linux-ld: drivers/net/phy/mdio_devres.o: in function `devm_mdiobus_unregister': drivers/net/phy/mdio_devres.c:53: undefined reference to `mdiobus_unregister' h8300-linux-ld: drivers/net/phy/mdio_devres.o: in function `devm_of_mdiobus_register': drivers/net/phy/mdio_devres.c:120: undefined reference to `of_mdiobus_register' h8300-linux-ld: drivers/net/phy/mdio_devres.o: in function `devm_mdiobus_alloc_size': drivers/net/phy/mdio_devres.c:38: undefined reference to `mdiobus_alloc_size' h8300-linux-ld: drivers/net/phy/mdio_devres.o: in function `__devm_mdiobus_register': drivers/net/phy/mdio_devres.c:87: undefined reference to `__mdiobus_register' h8300-linux-ld: drivers/net/phy/mdio-bcm-unimac.o: in function `unimac_mdio_reset': drivers/net/phy/mdio-bcm-unimac.c:181: undefined reference to `mdiobus_read' h8300-linux-ld: drivers/net/phy/mdio-bcm-unimac.o: in function `unimac_mdio_remove': drivers/net/phy/mdio-bcm-unimac.c:305: undefined reference to `mdiobus_unregister' h8300-linux-ld: drivers/net/phy/mdio-bcm-unimac.c:306: undefined reference to `mdiobus_free' h8300-linux-ld: drivers/net/phy/mdio-bcm-unimac.o: in function `mdiobus_alloc': h8300-linux-ld: drivers/net/phy/mdio-bcm-unimac.o: in function `unimac_mdio_probe': drivers/net/phy/mdio-bcm-unimac.c:282: undefined reference to `of_mdiobus_register' h8300-linux-ld: drivers/net/phy/mdio-bcm-unimac.c:295: undefined reference to `mdiobus_free' h8300-linux-ld: drivers/net/phy/mdio-bitbang.o: in function `mdiobus_alloc': h8300-linux-ld: drivers/net/phy/mdio-bitbang.o: in function `free_mdio_bitbang': drivers/net/phy/mdio-bitbang.c:228: undefined reference to `mdiobus_free' h8300-linux-ld: drivers/net/phy/mdio-mvusb.o: in function `mvusb_mdio_disconnect': drivers/net/phy/mdio-mvusb.c:104: undefined reference to `mdiobus_unregister' h8300-linux-ld: drivers/net/phy/mdio-mvusb.o: in function `mvusb_mdio_probe': drivers/net/phy/mdio-mvusb.c:96: undefined reference to `of_mdiobus_register' h8300-linux-ld: drivers/net/pcs/pcs-xpcs.o: in function `xpcs_read': drivers/net/pcs/pcs-xpcs.c:151: undefined reference to `mdiobus_read' h8300-linux-ld: drivers/net/pcs/pcs-xpcs.o: in function `xpcs_write': drivers/net/pcs/pcs-xpcs.c:158: undefined reference to `mdiobus_write' h8300-linux-ld: drivers/net/pcs/pcs-xpcs.o:drivers/net/pcs/pcs-xpcs.c:158: more undefined references to `mdiobus_write' follow # 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 2fa4e4b799e191530edbae4b96b85d4486e55053 vim +320 include/linux/phy.h 00db8189d984d6 Andy Fleming 2005-07-30 316 eb8a54a78e974e Timur Tabi 2012-01-12 317 struct mii_bus *mdiobus_alloc_size(size_t); eb8a54a78e974e Timur Tabi 2012-01-12 318 static inline struct mii_bus *mdiobus_alloc(void) eb8a54a78e974e Timur Tabi 2012-01-12 319 { eb8a54a78e974e Timur Tabi 2012-01-12 @320 return mdiobus_alloc_size(0); eb8a54a78e974e Timur Tabi 2012-01-12 321 } eb8a54a78e974e Timur Tabi 2012-01-12 322 :::::: The code at line 320 was first introduced by commit :::::: eb8a54a78e974e1af3e17fa38bb74d3747c5c1bd phylib: introduce mdiobus_alloc_size() :::::: TO: Timur Tabi <timur(a)freescale.com&gt; :::::: CC: David S. Miller <davem(a)davemloft.net&gt; --- 0-DAY CI Kernel Test Service, Intel Corporation https://lists.01.org/hyperkitty/list/kbuild-all@lists.01.org