Hi Jakub,

Thank you for the patch! Yet something to improve:

[auto build test ERROR on bpf-next/master]
[also build test ERROR on bpf/master net/master net-next/master linus/master ipvs/master v5.5-rc5 next-20200110]
[if your patch is applied to the wrong git tree, please drop us a note to help
improve the system. BTW, we also suggest to use '--base' option to specify the
base tree in git format-patch, please see https://stackoverflow.com/a/37406982]

url:    https://github.com/0day-ci/linux/commits/Jakub-Sitnicki/Extend-SOCKMAP-to-store-listening-sockets/20200111-045213
base:   https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next.git master
config: arc-defconfig (attached as .config)
compiler: arc-elf-gcc (GCC) 9.2.0
reproduce:
        wget https://raw.githubusercontent.com/intel/lkp-tests/master/sbin/make.cross -O ~/bin/make.cross
        chmod +x ~/bin/make.cross
        # save the attached .config to linux build tree
        GCC_VERSION=9.2.0 make.cross ARCH=arc 

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

All errors (new ones prefixed by >>):

   arc-elf-ld: net/ipv4/tcp_minisocks.o: in function `tcp_create_openreq_child':
   tcp_minisocks.c:(.text+0x474): undefined reference to `tcp_bpf_clone'

quoted

arc-elf-ld: tcp_minisocks.c:(.text+0x474): undefined reference to `tcp_bpf_clone'

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0-DAY kernel test infrastructure                 Open Source Technology Center
https://lists.01.org/hyperkitty/list/kbuild-all@lists.01.org Intel Corporation