[arnd-playground:ptp-1588-optional 1/1] (.text.__sock_recv_timestamp+0x3b8): undefined reference to `ptp_convert_timestamp'

[kernel test robot]

tree:   https://git.kernel.org/pub/scm/linux/kernel/git/arnd/playground.git ptp-1588-optional
head:   3f69b7366cfd4b2c048c76be5299b38066933ee1
commit: 3f69b7366cfd4b2c048c76be5299b38066933ee1 [1/1] ethernet: fix PTP_1588_CLOCK dependencies
config: mips-allmodconfig (attached as .config)
compiler: mips-linux-gcc (GCC) 10.3.0
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://git.kernel.org/pub/scm/linux/kernel/git/arnd/playground.git/commit/?id=3f69b7366cfd4b2c048c76be5299b38066933ee1
        git remote add arnd-playground https://git.kernel.org/pub/scm/linux/kernel/git/arnd/playground.git
        git fetch --no-tags arnd-playground ptp-1588-optional
        git checkout 3f69b7366cfd4b2c048c76be5299b38066933ee1
        # save the attached .config to linux build tree
        mkdir build_dir
        COMPILER_INSTALL_PATH=$HOME/0day COMPILER=gcc-10.3.0 make.cross O=build_dir ARCH=mips 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 >>):

   mips-linux-ld: net/socket.o: in function `__sock_recv_timestamp':
>> (.text.__sock_recv_timestamp+0x3b8): undefined reference to `ptp_convert_timestamp'
   mips-linux-ld: net/ethtool/common.o: in function `ethtool_get_phc_vclocks':
>> (.text.ethtool_get_phc_vclocks+0x98): undefined reference to `ptp_get_vclocks_index'

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

Attachment: .config.gz
Description: application/gzip