Hi Lorenzo,

Thank you for the patch! Perhaps something to improve:

[auto build test WARNING on bpf-next/master]

url:    https://github.com/0day-ci/linux/commits/Lorenzo-Fontana/tools-lib-bpf-bpf_program__insns-allow-to-retrieve-insns-in-libbpf/20210714-023628
base:   https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next.git master
config: x86_64-rhel-8.3-kselftests (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/999d9928ec3dd02a08da121d1377392681c84e51
        git remote add linux-review https://github.com/0day-ci/linux
        git fetch --no-tags linux-review Lorenzo-Fontana/tools-lib-bpf-bpf_program__insns-allow-to-retrieve-insns-in-libbpf/20210714-023628
        git checkout 999d9928ec3dd02a08da121d1377392681c84e51
        # save the attached .config to linux build tree
        make W=1 ARCH=x86_64 

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

All warnings (new ones prefixed by >>):

   Warning: Kernel ABI header at 'tools/include/uapi/linux/bpf.h' differs from latest version at 'include/uapi/linux/bpf.h'
   Warning: Kernel ABI header at 'tools/include/uapi/linux/netlink.h' differs from latest version at 'include/uapi/linux/netlink.h'
   Warning: Kernel ABI header at 'tools/include/uapi/linux/if_link.h' differs from latest version at 'include/uapi/linux/if_link.h'
   In file included from netlink.c:9:
   usr/include/linux/if_ether.h:169:1: warning: packed attribute is unnecessary for 'ethhdr' [-Wpacked]
     169 | } __attribute__((packed));
         | ^
   In file included from tools/include/uapi/linux/ethtool.h:19,
                    from xsk.c:18:
   usr/include/linux/if_ether.h:169:1: warning: packed attribute is unnecessary for 'ethhdr' [-Wpacked]
     169 | } __attribute__((packed));
         | ^
   In file included from tools/include/uapi/linux/ethtool.h:19,
                    from xsk.c:18:
   usr/include/linux/if_ether.h:169:1: warning: packed attribute is unnecessary for 'ethhdr' [-Wpacked]
     169 | } __attribute__((packed));
         | ^
   In file included from netlink.c:9:
   usr/include/linux/if_ether.h:169:1: warning: packed attribute is unnecessary for 'ethhdr' [-Wpacked]
     169 | } __attribute__((packed));
         | ^
>> Warning: Num of global symbols in /tools/build/libbpf/sharedobjs/libbpf-in.o (319) does NOT match with num of versioned symbols in /tools/build/libbpf/libbpf.so (318). Please make sure all LIBBPF_API symbols are versioned in libbpf.map.
   make[2]: *** [Makefile:186: check_abi] Error 1
   make[2]: Target 'all_cmd' not remade because of errors.

---
0-DAY CI Kernel Test Service, Intel Corporation
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