Hi Cong, I love your patch! Yet something to improve: [auto build test ERROR on bpf-next/master] url: https://github.com/0day-ci/linux/commits/Cong-Wang/sock_map-clean-up-and-... base: https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next.git master config: arm64-randconfig-r016-20210209 (attached as .config) compiler: clang version 12.0.0 (https://github.com/llvm/llvm-project c9439ca36342fb6013187d0a69aef92736951476) 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 # install arm64 cross compiling tool for clang build # apt-get install binutils-aarch64-linux-gnu # https://github.com/0day-ci/linux/commit/db0537152e20e7b3606cb5c5d6938077c... git remote add linux-review https://github.com/0day-ci/linux git fetch --no-tags linux-review Cong-Wang/sock_map-clean-up-and-refactor-code-for-BPF_SK_SKB_VERDICT/20210210-103313 git checkout db0537152e20e7b3606cb5c5d6938077c78b9341 # save the attached .config to linux build tree COMPILER_INSTALL_PATH=$HOME/0day COMPILER=clang make.cross ARCH=arm64 If you fix the issue, kindly add following tag as appropriate Reported-by: kernel test robot <lkp(a)intel.com&gt; All errors (new ones prefixed by >>): In file included from kernel/bpf/btf.c:22: struct skb_bpf_ext *ext = skb_ext_find(skb, SKB_EXT_BPF); ^ struct skb_bpf_ext *ext = skb_ext_find(skb, SKB_EXT_BPF); ^ include/linux/skmsg.h:474:28: error: implicit declaration of function 'skb_ext_find' [-Werror,-Wimplicit-function-declaration] struct skb_bpf_ext *ext = skb_ext_find(skb, SKB_EXT_BPF); ^ include/linux/skmsg.h:474:46: error: use of undeclared identifier 'SKB_EXT_BPF' struct skb_bpf_ext *ext = skb_ext_find(skb, SKB_EXT_BPF); ^ include/linux/skmsg.h:482:28: error: implicit declaration of function 'skb_ext_find' [-Werror,-Wimplicit-function-declaration] struct skb_bpf_ext *ext = skb_ext_find(skb, SKB_EXT_BPF); ^ include/linux/skmsg.h:482:46: error: use of undeclared identifier 'SKB_EXT_BPF' struct skb_bpf_ext *ext = skb_ext_find(skb, SKB_EXT_BPF); ^ include/linux/skmsg.h:490:28: error: implicit declaration of function 'skb_ext_find' [-Werror,-Wimplicit-function-declaration] struct skb_bpf_ext *ext = skb_ext_find(skb, SKB_EXT_BPF); ^ include/linux/skmsg.h:490:46: error: use of undeclared identifier 'SKB_EXT_BPF' struct skb_bpf_ext *ext = skb_ext_find(skb, SKB_EXT_BPF); ^ 8 errors generated. Kconfig warnings: (for reference only) WARNING: unmet direct dependencies detected for NET_SOCK_MSG Depends on NET Selected by - BPF_SYSCALL vim +/skb_ext_find +466 include/linux/skmsg.h 461 462 #if IS_ENABLED(CONFIG_NET_SOCK_MSG) 463 static inline 464 bool skb_bpf_ext_ingress(const struct sk_buff *skb) 465 { 467 468 return ext->flags & BPF_F_INGRESS; 469 } 470 --- 0-DAY CI Kernel Test Service, Intel Corporation https://lists.01.org/hyperkitty/list/kbuild-all@lists.01.org