[kbuild-all] [rgushchin:bpf_memcg.7 7/35] include/linux/bpf.h:1257:9: warning: returning 'int' from a function with return type 'void makes pointer from integer without a cast

tree: https://github.com/rgushchin/linux.git bpf_memcg.7 head: d2ca788c20f96de607dc8d3dae47b4a7c6cc3ab5 commit: 7521b59a5c7a4976d908665c1700783564344979 [7/35] bpf: prepare for memcg-based memory accounting for bpf maps config: c6x-randconfig-r005-20201119 (attached as .config) compiler: c6x-elf-gcc (GCC) 9.3.0 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/rgushchin/linux/commit/7521b59a5c7a4976d908665c1700783... git remote add rgushchin https://github.com/rgushchin/linux.git git fetch --no-tags rgushchin bpf_memcg.7 git checkout 7521b59a5c7a4976d908665c1700783564344979 # save the attached .config to linux build tree COMPILER_INSTALL_PATH=$HOME/0day COMPILER=gcc-9.3.0 make.cross ARCH=c6x If you fix the issue, kindly add following tag as appropriate Reported-by: kernel test robot <lkp(a)intel.com&gt; All warnings (new ones prefixed by >>): In file included from kernel/bpf/syscall.c:4: include/linux/bpf.h: In function 'bpf_map_kmalloc_node': include/linux/bpf.h:1257:9: error: implicit declaration of function 'kmalloc_node'; did you mean 'kvmalloc_node'? [-Werror=implicit-function-declaration] 1257 | return kmalloc_node(size, flags, node); | ^~~~~~~~~~~~ | kvmalloc_node 1257 | return kmalloc_node(size, flags, node); | ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ In file included from include/linux/sockptr.h:11, from include/linux/net.h:25, from include/linux/skbuff.h:26, from include/linux/if_ether.h:19, from include/uapi/linux/ethtool.h:19, from include/linux/ethtool.h:18, from include/linux/netdevice.h:37, from include/trace/events/xdp.h:8, from include/linux/bpf_trace.h:5, from kernel/bpf/syscall.c:5: include/linux/slab.h: At top level: include/linux/slab.h:560:30: error: conflicting types for 'kmalloc_node' 560 | static __always_inline void *kmalloc_node(size_t size, gfp_t flags, int node) | ^~~~~~~~~~~~ In file included from kernel/bpf/syscall.c:4: include/linux/bpf.h:1257:9: note: previous implicit declaration of 'kmalloc_node' was here 1257 | return kmalloc_node(size, flags, node); | ^~~~~~~~~~~~ cc1: some warnings being treated as errors -- In file included from kernel/bpf/hashtab.c:5: include/linux/bpf.h: In function 'bpf_map_kmalloc_node': include/linux/bpf.h:1257:9: error: implicit declaration of function 'kmalloc_node'; did you mean 'kvmalloc_node'? [-Werror=implicit-function-declaration] 1257 | return kmalloc_node(size, flags, node); | ^~~~~~~~~~~~ | kvmalloc_node 1257 | return kmalloc_node(size, flags, node); | ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ In file included from include/linux/sockptr.h:11, from include/linux/net.h:25, from include/linux/skbuff.h:26, from include/linux/filter.h:13, from kernel/bpf/hashtab.c:8: include/linux/slab.h: At top level: include/linux/slab.h:560:30: error: conflicting types for 'kmalloc_node' 560 | static __always_inline void *kmalloc_node(size_t size, gfp_t flags, int node) | ^~~~~~~~~~~~ In file included from kernel/bpf/hashtab.c:5: include/linux/bpf.h:1257:9: note: previous implicit declaration of 'kmalloc_node' was here 1257 | return kmalloc_node(size, flags, node); | ^~~~~~~~~~~~ In file included from kernel/bpf/hashtab.c:8: kernel/bpf/hashtab.c: In function 'htab_map_gen_lookup': include/linux/filter.h:345:4: warning: cast between incompatible function types from 'void * (*)(struct bpf_map *, void *)' to 'u64 (*)(u64, u64, u64, u64, u64)' {aka 'long long unsigned int (*)(long long unsigned int, long long unsigned int, long long unsigned int, long long unsigned int, long long unsigned int)'} [-Wcast-function-type] 345 | ((u64 (*)(u64, u64, u64, u64, u64))(x)) | ^ include/linux/filter.h:353:14: note: in definition of macro 'BPF_EMIT_CALL' 353 | .imm = ((FUNC) - __bpf_call_base) }) | ^~~~ kernel/bpf/hashtab.c:653:26: note: in expansion of macro 'BPF_CAST_CALL' 653 | *insn++ = BPF_EMIT_CALL(BPF_CAST_CALL(__htab_map_lookup_elem)); | ^~~~~~~~~~~~~ kernel/bpf/hashtab.c: In function 'htab_lru_map_gen_lookup': include/linux/filter.h:345:4: warning: cast between incompatible function types from 'void * (*)(struct bpf_map *, void *)' to 'u64 (*)(u64, u64, u64, u64, u64)' {aka 'long long unsigned int (*)(long long unsigned int, long long unsigned int, long long unsigned int, long long unsigned int, long long unsigned int)'} [-Wcast-function-type] 345 | ((u64 (*)(u64, u64, u64, u64, u64))(x)) | ^ include/linux/filter.h:353:14: note: in definition of macro 'BPF_EMIT_CALL' 353 | .imm = ((FUNC) - __bpf_call_base) }) | ^~~~ kernel/bpf/hashtab.c:694:26: note: in expansion of macro 'BPF_CAST_CALL' 694 | *insn++ = BPF_EMIT_CALL(BPF_CAST_CALL(__htab_map_lookup_elem)); | ^~~~~~~~~~~~~ kernel/bpf/hashtab.c: In function 'htab_of_map_gen_lookup': include/linux/filter.h:345:4: warning: cast between incompatible function types from 'void * (*)(struct bpf_map *, void *)' to 'u64 (*)(u64, u64, u64, u64, u64)' {aka 'long long unsigned int (*)(long long unsigned int, long long unsigned int, long long unsigned int, long long unsigned int, long long unsigned int)'} [-Wcast-function-type] 345 | ((u64 (*)(u64, u64, u64, u64, u64))(x)) | ^ include/linux/filter.h:353:14: note: in definition of macro 'BPF_EMIT_CALL' 353 | .imm = ((FUNC) - __bpf_call_base) }) | ^~~~ kernel/bpf/hashtab.c:2161:26: note: in expansion of macro 'BPF_CAST_CALL' 2161 | *insn++ = BPF_EMIT_CALL(BPF_CAST_CALL(__htab_map_lookup_elem)); | ^~~~~~~~~~~~~ cc1: some warnings being treated as errors -- In file included from kernel/bpf/disasm.c:6: include/linux/bpf.h: In function 'bpf_map_kmalloc_node': include/linux/bpf.h:1257:9: error: implicit declaration of function 'kmalloc_node'; did you mean 'kvmalloc_node'? [-Werror=implicit-function-declaration] 1257 | return kmalloc_node(size, flags, node); | ^~~~~~~~~~~~ | kvmalloc_node 1257 | return kmalloc_node(size, flags, node); | ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ cc1: some warnings being treated as errors vim +1257 include/linux/bpf.h 1246 1247 #ifdef CONFIG_MEMCG_KMEM 1248 void *bpf_map_kmalloc_node(const struct bpf_map *map, size_t size, gfp_t flags, 1249 int node); 1250 void __percpu *bpf_map_alloc_percpu(const struct bpf_map *map, size_t size, 1251 size_t align, gfp_t gfp); 1252 #else 1253 static inline void * 1254 bpf_map_kmalloc_node(const struct bpf_map *map, size_t size, gfp_t flags, 1255 int node) 1256 { 1258 } 1259 --- 0-DAY CI Kernel Test Service, Intel Corporation https://lists.01.org/hyperkitty/list/kbuild-all@lists.01.org