Hi Yangbo, I love your patch! Yet something to improve: [auto build test ERROR on 392c36e5be1dee19ffce8c8ba8f07f90f5aa3f7c] url: https://github.com/0day-ci/linux/commits/Yangbo-Lu/Support-ocelot-PTP-Syn... base: 392c36e5be1dee19ffce8c8ba8f07f90f5aa3f7c config: i386-randconfig-r035-20210416 (attached as .config) compiler: gcc-9 (Debian 9.3.0-22) 9.3.0 reproduce (this is a W=1 build): # https://github.com/0day-ci/linux/commit/7e3d064908a2ecf6287c2eb40e0a36d86... git remote add linux-review https://github.com/0day-ci/linux git fetch --no-tags linux-review Yangbo-Lu/Support-ocelot-PTP-Sync-one-step-timestamping/20210416-203333 git checkout 7e3d064908a2ecf6287c2eb40e0a36d86434f41c # save the attached .config to linux build tree make W=1 W=1 ARCH=i386 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 <<): --- 0-DAY CI Kernel Test Service, Intel Corporation https://lists.01.org/hyperkitty/list/kbuild-all@lists.01.org