Hi Xin,

Thank you for the patch! Yet something to improve:

[auto build test ERROR on net-next/master]

url:    https://github.com/0day-ci/linux/commits/Xin-Long/net-enable-udp-v6-sockets-receiving-v4-packets-with-UDP-GRO/20210111-205115
base:   https://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next.git 73b7a6047971aa6ce4a70fc4901964d14f077171
config: m68k-defconfig (attached as .config)
compiler: m68k-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
        # https://github.com/0day-ci/linux/commit/62229592b4c3e929eeafea82e758dacb2953fbde
        git remote add linux-review https://github.com/0day-ci/linux
        git fetch --no-tags linux-review Xin-Long/net-enable-udp-v6-sockets-receiving-v4-packets-with-UDP-GRO/20210111-205115
        git checkout 62229592b4c3e929eeafea82e758dacb2953fbde
        # save the attached .config to linux build tree
        COMPILER_INSTALL_PATH=$HOME/0day COMPILER=gcc-9.3.0 make.cross ARCH=m68k 

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

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

quoted

ERROR: modpost: "udp_encap_needed_key" [net/ipv6/ipv6.ko] undefined!

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