tree: git://git.kraxel.org/linux drm-qemu-next head: c84adb304c100cb9555f64f49c1d84a01fac3616 commit: a0308938ec81cd0dca9d75833ec0dd1b8708917e [6/8] virtio: add dma-buf support for exported objects config: microblaze-randconfig-r021-20200818 (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 a0308938ec81cd0dca9d75833ec0dd1b8708917e # 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 <lkp(a)intel.com&gt; All errors (new ones prefixed by >>, old ones prefixed by <<): WARNING: modpost: missing MODULE_LICENSE() in drivers/virtio/virtio_dma_buf.o ERROR: modpost: "min_low_pfn" [net/9p/9pnet_virtio.ko] undefined! ERROR: modpost: "min_low_pfn" [net/sunrpc/xprtrdma/rpcrdma.ko] undefined! ERROR: modpost: "min_low_pfn" [drivers/rpmsg/virtio_rpmsg_bus.ko] undefined! ERROR: modpost: "min_low_pfn" [drivers/tty/serial/fsl_lpuart.ko] undefined! ERROR: modpost: "min_low_pfn" [crypto/ccm.ko] undefined! --- 0-DAY CI Kernel Test Service, Intel Corporation https://lists.01.org/hyperkitty/list/kbuild-all@lists.01.org