Hi Lingpeng,

Thank you for the patch! Yet something to improve:

[auto build test ERROR on bpf-next/master]
[also build test ERROR on bpf/master]
[cannot apply to v5.5]
[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/Lingpeng-Chen/bpf-Add-sock-ops-get-netns-helpers/20200207-212755
base:   https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next.git master
config: h8300-randconfig-a001-20200207 (attached as .config)
compiler: h8300-linux-gcc (GCC) 7.5.0
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=7.5.0 make.cross ARCH=h8300 

If you fix the issue, kindly add following tag
Reported-by: kbuild test robot <lkp@intel.com>

All errors (new ones prefixed by >>):

   In file included from arch/h8300/include/asm/atomic.h:7:0,
                    from include/linux/atomic.h:7,
                    from include/asm-generic/bitops/lock.h:5,
                    from arch/h8300/include/asm/bitops.h:170,
                    from include/linux/bitops.h:26,
                    from include/linux/kernel.h:12,
                    from include/linux/list.h:9,
                    from include/linux/module.h:12,
                    from net/core/filter.c:20:
   net/core/filter.c: In function 'bpf_clear_redirect_map':
   arch/h8300/include/asm/cmpxchg.h:54:3: warning: value computed is not used [-Wunused-value]
     ((__typeof__(*(ptr)))__cmpxchg_local_generic((ptr),   \
     ~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
               (unsigned long)(o), \
               ~~~~~~~~~~~~~~~~~~~~~
               (unsigned long)(n), \
               ~~~~~~~~~~~~~~~~~~~~~
               sizeof(*(ptr))))
               ~~~~~~~~~~~~~~~~
   include/asm-generic/cmpxchg.h:106:28: note: in expansion of macro 'cmpxchg_local'
    #define cmpxchg(ptr, o, n) cmpxchg_local((ptr), (o), (n))
                               ^~~~~~~~~~~~~
   net/core/filter.c:3516:4: note: in expansion of macro 'cmpxchg'
       cmpxchg(&ri->map, map, NULL);
       ^~~~~~~
   net/core/filter.c: In function '____bpf_sock_ops_get_netns':
>> net/core/filter.c:4430:19: error: 'possible_net_t {aka struct <anonymous>}' has no member named 'net'
     return sk->sk_net.net->ns.inum;
                      ^

vim +4430 net/core/filter.c

  4423	
  4424	BPF_CALL_1(bpf_sock_ops_get_netns, struct bpf_sock_ops_kern *, bpf_sock)
  4425	{
  4426		struct sock *sk = bpf_sock->sk;
  4427	
  4428		if (!IS_ENABLED(CONFIG_NET_NS))
  4429			return 0;
> 4430		return sk->sk_net.net->ns.inum;
  4431	}
  4432	

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