Hi Xu, Thank you for the patch! Perhaps something to improve: [auto build test WARNING on bpf-next/master] url: https://github.com/intel-lab-lkp/linux/commits/Xu-Kuohai/bpf-add-bound-tracking-for-BPF_MOD/20230305-223257 base: https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next.git master patch link: https://lore.kernel.org/r/20230306033119.2634976-2-xukuohai%40huaweicloud.com patch subject: [PATCH bpf-next 1/2] bpf: add bound tracking for BPF_MOD config: arm-randconfig-r025-20230305 (https://download.01.org/0day-ci/archive/20230306/202303060036.zK05OC5M-lkp@xxxxxxxxx/config) compiler: clang version 17.0.0 (https://github.com/llvm/llvm-project 67409911353323ca5edf2049ef0df54132fa1ca7) 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 arm cross compiling tool for clang build # apt-get install binutils-arm-linux-gnueabi # https://github.com/intel-lab-lkp/linux/commit/e66c7bbd32e375af92c776a2b9f51be4c515ad71 git remote add linux-review https://github.com/intel-lab-lkp/linux git fetch --no-tags linux-review Xu-Kuohai/bpf-add-bound-tracking-for-BPF_MOD/20230305-223257 git checkout e66c7bbd32e375af92c776a2b9f51be4c515ad71 # save the config file mkdir build_dir && cp config build_dir/.config COMPILER_INSTALL_PATH=$HOME/0day COMPILER=clang make.cross W=1 O=build_dir ARCH=arm olddefconfig COMPILER_INSTALL_PATH=$HOME/0day COMPILER=clang make.cross W=1 O=build_dir ARCH=arm SHELL=/bin/bash kernel/bpf/ 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/202303060036.zK05OC5M-lkp@xxxxxxxxx/ All warnings (new ones prefixed by >>): kernel/bpf/verifier.c:10298:24: warning: array index 16 is past the end of the array (that has type 'u32[16]' (aka 'unsigned int[16]')) [-Warray-bounds] meta.func_id == special_kfunc_list[KF_bpf_dynptr_slice_rdwr]) { ^ ~~~~~~~~~~~~~~~~~~~~~~~~ kernel/bpf/verifier.c:9150:1: note: array 'special_kfunc_list' declared here BTF_ID_LIST(special_kfunc_list) ^ include/linux/btf_ids.h:207:27: note: expanded from macro 'BTF_ID_LIST' #define BTF_ID_LIST(name) static u32 __maybe_unused name[16]; ^ >> kernel/bpf/verifier.c:11622:13: warning: comparison of distinct pointer types ('typeof ((umax)) *' (aka 'unsigned int *') and 'uint64_t *' (aka 'unsigned long long *')) [-Wcompare-distinct-pointer-types] umax_rem = do_div(umax, val); ^~~~~~~~~~~~~~~~~ include/asm-generic/div64.h:222:28: note: expanded from macro 'do_div' (void)(((typeof((n)) *)0) == ((uint64_t *)0)); \ ~~~~~~~~~~~~~~~~~~ ^ ~~~~~~~~~~~~~~~ kernel/bpf/verifier.c:11622:13: error: incompatible pointer types passing 'u32 *' (aka 'unsigned int *') to parameter of type 'uint64_t *' (aka 'unsigned long long *') [-Werror,-Wincompatible-pointer-types] umax_rem = do_div(umax, val); ^~~~~~~~~~~~~~~~~ include/asm-generic/div64.h:238:22: note: expanded from macro 'do_div' __rem = __div64_32(&(n), __base); \ ^~~~ arch/arm/include/asm/div64.h:24:45: note: passing argument to parameter 'n' here static inline uint32_t __div64_32(uint64_t *n, uint32_t base) ^ >> kernel/bpf/verifier.c:11623:13: warning: comparison of distinct pointer types ('typeof ((umin)) *' (aka 'unsigned int *') and 'uint64_t *' (aka 'unsigned long long *')) [-Wcompare-distinct-pointer-types] umin_rem = do_div(umin, val); ^~~~~~~~~~~~~~~~~ include/asm-generic/div64.h:222:28: note: expanded from macro 'do_div' (void)(((typeof((n)) *)0) == ((uint64_t *)0)); \ ~~~~~~~~~~~~~~~~~~ ^ ~~~~~~~~~~~~~~~ kernel/bpf/verifier.c:11623:13: error: incompatible pointer types passing 'u32 *' (aka 'unsigned int *') to parameter of type 'uint64_t *' (aka 'unsigned long long *') [-Werror,-Wincompatible-pointer-types] umin_rem = do_div(umin, val); ^~~~~~~~~~~~~~~~~ include/asm-generic/div64.h:238:22: note: expanded from macro 'do_div' __rem = __div64_32(&(n), __base); \ ^~~~ arch/arm/include/asm/div64.h:24:45: note: passing argument to parameter 'n' here static inline uint32_t __div64_32(uint64_t *n, uint32_t base) ^ >> kernel/bpf/verifier.c:11622:13: warning: shift count >= width of type [-Wshift-count-overflow] umax_rem = do_div(umax, val); ^~~~~~~~~~~~~~~~~ include/asm-generic/div64.h:234:25: note: expanded from macro 'do_div' } else if (likely(((n) >> 32) == 0)) { \ ^ ~~ include/linux/compiler.h:77:40: note: expanded from macro 'likely' # define likely(x) __builtin_expect(!!(x), 1) ^ kernel/bpf/verifier.c:11623:13: warning: shift count >= width of type [-Wshift-count-overflow] umin_rem = do_div(umin, val); ^~~~~~~~~~~~~~~~~ include/asm-generic/div64.h:234:25: note: expanded from macro 'do_div' } else if (likely(((n) >> 32) == 0)) { \ ^ ~~ include/linux/compiler.h:77:40: note: expanded from macro 'likely' # define likely(x) __builtin_expect(!!(x), 1) ^ 5 warnings and 2 errors generated. vim +11622 kernel/bpf/verifier.c 11606 11607 static void scalar32_min_max_mod(struct bpf_reg_state *dst_reg, 11608 struct bpf_reg_state *src_reg) 11609 { 11610 u32 val = (u32)src_reg->var_off.value; /* src_reg is const */ 11611 u32 umax = dst_reg->u32_max_value; 11612 u32 umin = dst_reg->u32_min_value; 11613 u32 umax_rem, umin_rem; 11614 11615 /* dst_reg is 32-bit truncated when mod32 zero, since 11616 * adjust_scalar_min_max_vals calls zext_32_to_64 to do truncation for 11617 * all alu32 ops, here we do nothing and just return. 11618 */ 11619 if (!val) 11620 return; 11621 11622 umax_rem = do_div(umax, val); 11623 umin_rem = do_div(umin, val); 11624 11625 /* no winding */ 11626 if (umax - umin < val && umin_rem <= umax_rem) { 11627 dst_reg->var_off = tnum_range(umin_rem, umax_rem); 11628 dst_reg->u32_min_value = umin_rem; 11629 dst_reg->u32_max_value = umax_rem; 11630 } else { 11631 dst_reg->var_off = tnum_range(0, val - 1); 11632 dst_reg->u32_min_value = 0; 11633 dst_reg->u32_max_value = val - 1; 11634 } 11635 11636 /* cross the sign boundary */ 11637 if ((s32)dst_reg->u32_min_value > (s32)dst_reg->u32_max_value) { 11638 dst_reg->s32_min_value = S32_MIN; 11639 dst_reg->s32_max_value = S32_MAX; 11640 } else { 11641 dst_reg->s32_min_value = (s32)dst_reg->u32_min_value; 11642 dst_reg->s32_max_value = (s32)dst_reg->u32_max_value; 11643 } 11644 11645 /* mark reg64 unbounded to deduce 64-bit bounds from var_off */ 11646 __mark_reg64_unbounded(dst_reg); 11647 } 11648 -- 0-DAY CI Kernel Test Service https://github.com/intel/lkp-tests
