Hi Yafang, kernel test robot noticed the following build errors: [auto build test ERROR on bpf-next/master] url: https://github.com/intel-lab-lkp/linux/commits/Yafang-Shao/bpf-Add-__rcu_read_-lock-unlock-into-btf-id-deny-list/20230417-235009 base: https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next.git master patch link: https://lore.kernel.org/r/20230417154737.12740-6-laoar.shao%40gmail.com patch subject: [PATCH bpf-next 5/6] bpf: Improve tracing recursion prevention mechanism config: loongarch-defconfig (https://download.01.org/0day-ci/archive/20230418/202304180736.cWjpwhs6-lkp@xxxxxxxxx/config) compiler: loongarch64-linux-gcc (GCC) 12.1.0 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/intel-lab-lkp/linux/commit/ac84d2623c0469a703245030f2b23612ab4505dd git remote add linux-review https://github.com/intel-lab-lkp/linux git fetch --no-tags linux-review Yafang-Shao/bpf-Add-__rcu_read_-lock-unlock-into-btf-id-deny-list/20230417-235009 git checkout ac84d2623c0469a703245030f2b23612ab4505dd # save the config file mkdir build_dir && cp config build_dir/.config COMPILER_INSTALL_PATH=$HOME/0day COMPILER=gcc-12.1.0 make.cross W=1 O=build_dir ARCH=loongarch olddefconfig COMPILER_INSTALL_PATH=$HOME/0day COMPILER=gcc-12.1.0 make.cross W=1 O=build_dir ARCH=loongarch SHELL=/bin/bash If you fix the issue, kindly add following tag where applicable | Reported-by: kernel test robot <lkp@xxxxxxxxx> | Link: https://lore.kernel.org/oe-kbuild-all/202304180736.cWjpwhs6-lkp@xxxxxxxxx/ All errors (new ones prefixed by >>): kernel/bpf/trampoline.c: In function '__bpf_prog_enter_recur': >> kernel/bpf/trampoline.c:848:15: error: implicit declaration of function 'test_recursion_try_acquire' [-Werror=implicit-function-declaration] 848 | bit = test_recursion_try_acquire(_THIS_IP_, _RET_IP_); | ^~~~~~~~~~~~~~~~~~~~~~~~~~ kernel/bpf/trampoline.c: In function '__bpf_prog_exit_recur': >> kernel/bpf/trampoline.c:896:9: error: implicit declaration of function 'test_recursion_release'; did you mean 'dev_recursion_level'? [-Werror=implicit-function-declaration] 896 | test_recursion_release(run_ctx->recursion_bit); | ^~~~~~~~~~~~~~~~~~~~~~ | dev_recursion_level cc1: some warnings being treated as errors vim +/test_recursion_try_acquire +848 kernel/bpf/trampoline.c 828 829 /* The logic is similar to bpf_prog_run(), but with an explicit 830 * rcu_read_lock() and migrate_disable() which are required 831 * for the trampoline. The macro is split into 832 * call __bpf_prog_enter 833 * call prog->bpf_func 834 * call __bpf_prog_exit 835 * 836 * __bpf_prog_enter returns: 837 * 0 - skip execution of the bpf prog 838 * 1 - execute bpf prog 839 * [2..MAX_U64] - execute bpf prog and record execution time. 840 * This is start time. 841 */ 842 static u64 notrace __bpf_prog_enter_recur(struct bpf_prog *prog, struct bpf_tramp_run_ctx *run_ctx) 843 __acquires(RCU) 844 { 845 int bit; 846 847 rcu_read_lock(); > 848 bit = test_recursion_try_acquire(_THIS_IP_, _RET_IP_); 849 run_ctx->recursion_bit = bit; 850 if (bit < 0) { 851 preempt_disable_notrace(); 852 bpf_prog_inc_misses_counter(prog); 853 preempt_enable_notrace(); 854 return 0; 855 } 856 857 migrate_disable(); 858 859 run_ctx->saved_run_ctx = bpf_set_run_ctx(&run_ctx->run_ctx); 860 return bpf_prog_start_time(); 861 } 862 863 static void notrace update_prog_stats(struct bpf_prog *prog, 864 u64 start) 865 { 866 struct bpf_prog_stats *stats; 867 868 if (static_branch_unlikely(&bpf_stats_enabled_key) && 869 /* static_key could be enabled in __bpf_prog_enter* 870 * and disabled in __bpf_prog_exit*. 871 * And vice versa. 872 * Hence check that 'start' is valid. 873 */ 874 start > NO_START_TIME) { 875 unsigned long flags; 876 877 stats = this_cpu_ptr(prog->stats); 878 flags = u64_stats_update_begin_irqsave(&stats->syncp); 879 u64_stats_inc(&stats->cnt); 880 u64_stats_add(&stats->nsecs, sched_clock() - start); 881 u64_stats_update_end_irqrestore(&stats->syncp, flags); 882 } 883 } 884 885 static void notrace __bpf_prog_exit_recur(struct bpf_prog *prog, u64 start, 886 struct bpf_tramp_run_ctx *run_ctx) 887 __releases(RCU) 888 { 889 if (run_ctx->recursion_bit < 0) 890 goto out; 891 892 bpf_reset_run_ctx(run_ctx->saved_run_ctx); 893 894 update_prog_stats(prog, start); 895 migrate_enable(); > 896 test_recursion_release(run_ctx->recursion_bit); 897 898 out: 899 rcu_read_unlock(); 900 } 901 -- 0-DAY CI Kernel Test Service https://github.com/intel/lkp-tests
