[luxis1999-iommufd:iommufd-v5.16-rc3 15/25] ERROR: modpost: "vfio_platform_ops" [drivers/vfio/platform/vfio-platform.ko] undefined!

[kernel test robot]

tree:   https://github.com/luxis1999/iommufd iommufd-v5.16-rc3
head:   21c1bb93447d6cced2f486cdb68b92d11f2e664d
commit: efdbba2a0f53aec4a2774306cead86075b7351b4 [15/25] vifo_platform: Use vfio_alloc/put_device()
config: m68k-allmodconfig (https://download.01.org/0day-ci/archive/20211217/202112170050.8LrWj0Aj-lkp@xxxxxxxxx/config)
compiler: m68k-linux-gcc (GCC) 11.2.0
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
        # https://github.com/luxis1999/iommufd/commit/efdbba2a0f53aec4a2774306cead86075b7351b4
        git remote add luxis1999-iommufd https://github.com/luxis1999/iommufd
        git fetch --no-tags luxis1999-iommufd iommufd-v5.16-rc3
        git checkout efdbba2a0f53aec4a2774306cead86075b7351b4
        # save the config file to linux build tree
        mkdir build_dir
        COMPILER_INSTALL_PATH=$HOME/0day COMPILER=gcc-11.2.0 make.cross O=build_dir ARCH=m68k SHELL=/bin/bash

If you fix the issue, kindly add following tag as appropriate
Reported-by: kernel test robot <lkp@xxxxxxxxx>

All errors (new ones prefixed by >>, old ones prefixed by <<):

>> ERROR: modpost: "vfio_platform_ops" [drivers/vfio/platform/vfio-platform.ko] undefined!

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0-DAY CI Kernel Test Service, Intel Corporation
https://lists.01.org/hyperkitty/list/kbuild-all@xxxxxxxxxxxx