Hi Arnd, First bad commit (maybe != root cause): tree: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git master head: 1590a2e1c681b0991bd42c992cabfd380e0338f2 commit: 710ec38b0f633ab3e2581f07a73442d809e28ab0 mm: add dummy can_do_mlock() helper date: 9 months ago config: microblaze-randconfig-r026-20200624 (attached as .config) compiler: microblaze-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 710ec38b0f633ab3e2581f07a73442d809e28ab0 # save the attached .config to linux build tree COMPILER_INSTALL_PATH=$HOME/0day COMPILER=gcc-9.3.0 make.cross ARCH=microblaze If you fix the issue, kindly add following tag as appropriate Reported-by: kernel test robot All errors (new ones prefixed by >>): ERROR: "min_low_pfn" [drivers/block/aoe/aoe.ko] undefined! >> ERROR: "min_low_pfn" [drivers/scsi/qedf/qedf.ko] undefined! --- 0-DAY CI Kernel Test Service, Intel Corporation https://lists.01.org/hyperkitty/list/kbuild-all@lists.01.org