Hi Keqian, Thank you for the patch! Yet something to improve: [auto build test ERROR on vfio/next] [also build test ERROR on linux/master linus/master v5.12-rc7 next-20210413] [If your patch is applied to the wrong git tree, kindly drop us a note. And when submitting patch, we suggest to use '--base' as documented in https://git-scm.com/docs/git-format-patch] url: https://github.com/0day-ci/linux/commits/Keqian-Zhu/vfio-iommu_type1-Impl... base: https://github.com/awilliam/linux-vfio.git next config: arm-randconfig-r015-20210413 (attached as .config) compiler: arm-linux-gnueabi-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 # https://github.com/0day-ci/linux/commit/3005ed21d06a3ed861847529f08c3d881... git remote add linux-review https://github.com/0day-ci/linux git fetch --no-tags linux-review Keqian-Zhu/vfio-iommu_type1-Implement-dirty-log-tracking-based-on-IOMMU-HWDBM/20210413-171632 git checkout 3005ed21d06a3ed861847529f08c3d8814013399 # save the attached .config to linux build tree COMPILER_INSTALL_PATH=$HOME/0day COMPILER=gcc-9.3.0 make.cross ARCH=arm 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 >>): drivers/vfio/vfio_iommu_type1.c: In function 'vfio_group_supports_hwdbm': 2270 | enum iommu_dev_features feat = IOMMU_DEV_FEAT_HWDBM; | ^~~~~~~~~~~~~~~~~~~~ | IOMMU_DEV_FEAT_SVA drivers/vfio/vfio_iommu_type1.c:2270:33: note: each undeclared identifier is reported only once for each function it appears in vim +2270 drivers/vfio/vfio_iommu_type1.c 2267 2268 static bool vfio_group_supports_hwdbm(struct vfio_group *group) 2269 { 2271 2272 return !iommu_group_for_each_dev(group->iommu_group, &feat, 2273 vfio_dev_enable_feature); 2274 } 2275 --- 0-DAY CI Kernel Test Service, Intel Corporation https://lists.01.org/hyperkitty/list/kbuild-all@lists.01.org