[sashal-next:mm-next 5/7] arch/loongarch/net/bpf_jit.c:1322:7: error: call to undeclared function '__bpf_address_lookup'; ISO C99 and later do not support implicit function declarations

[sashal-next:mm-next 5/7] arch/loongarch/net/bpf_jit.c:1322:7: error: call to undeclared function '__bpf_address_lookup'; ISO C99 and later do not support implicit function declarations

[kernel test robot]

tree:   https://git.kernel.org/pub/scm/linux/kernel/git/sashal/linux-next.git mm-next
head:   e10a56cdd2c231b8e6e59651bf02e3878ea3cc76
commit: 5c48a0498b4b96a11af18d27ae295822bc40e0c3 [5/7] Merge 'mm-nonmm-unstable' from https://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm (mm-nonmm-unstable)
config: loongarch-randconfig-002-20260105 (https://download.01.org/0day-ci/archive/20260105/202601051241.10hXC1ge-lkp@intel.com/config)
compiler: clang version 22.0.0git (https://github.com/llvm/llvm-project 9b8addffa70cee5b2acc5454712d9cf78ce45710)
rustc: rustc 1.88.0 (6b00bc388 2025-06-23)
reproduce (this is a W=1 build): (https://download.01.org/0day-ci/archive/20260105/202601051241.10hXC1ge-lkp@intel.com/reproduce)

If you fix the issue in a separate patch/commit (i.e. not just a new version of
the same patch/commit), kindly add following tags
| Reported-by: kernel test robot <lkp@intel.com>
| Closes: https://lore.kernel.org/oe-kbuild-all/202601051241.10hXC1ge-lkp@intel.com/

All errors (new ones prefixed by >>):

>> arch/loongarch/net/bpf_jit.c:1322:7: error: call to undeclared function '__bpf_address_lookup'; ISO C99 and later do not support implicit function declarations [-Wimplicit-function-declaration]
    1322 |         if (!__bpf_address_lookup((unsigned long)ip, &size, &offset, namebuf))
         |              ^
   arch/loongarch/net/bpf_jit.c:1322:7: note: did you mean 'bpf_address_lookup'?
   include/linux/filter.h:1378:5: note: 'bpf_address_lookup' declared here
    1378 | int bpf_address_lookup(unsigned long addr, unsigned long *size,
         |     ^
   1 error generated.


vim +/__bpf_address_lookup +1322 arch/loongarch/net/bpf_jit.c

9fbd18cf4c69f51 Chenghao Duan 2025-08-05  1305  
ae4a3160d19cd16 Menglong Dong 2025-11-18  1306  int bpf_arch_text_poke(void *ip, enum bpf_text_poke_type old_t,
ae4a3160d19cd16 Menglong Dong 2025-11-18  1307  		       enum bpf_text_poke_type new_t, void *old_addr,
ae4a3160d19cd16 Menglong Dong 2025-11-18  1308  		       void *new_addr)
9fbd18cf4c69f51 Chenghao Duan 2025-08-05  1309  {
9fbd18cf4c69f51 Chenghao Duan 2025-08-05  1310  	int ret;
ae4a3160d19cd16 Menglong Dong 2025-11-18  1311  	bool is_call;
73721d8676771c6 Chenghao Duan 2025-12-31  1312  	unsigned long size = 0;
73721d8676771c6 Chenghao Duan 2025-12-31  1313  	unsigned long offset = 0;
73721d8676771c6 Chenghao Duan 2025-12-31  1314  	void *image = NULL;
73721d8676771c6 Chenghao Duan 2025-12-31  1315  	char namebuf[KSYM_NAME_LEN];
9fbd18cf4c69f51 Chenghao Duan 2025-08-05  1316  	u32 old_insns[LOONGARCH_LONG_JUMP_NINSNS] = {[0 ... 4] = INSN_NOP};
9fbd18cf4c69f51 Chenghao Duan 2025-08-05  1317  	u32 new_insns[LOONGARCH_LONG_JUMP_NINSNS] = {[0 ... 4] = INSN_NOP};
9fbd18cf4c69f51 Chenghao Duan 2025-08-05  1318  
3d770bd11b94306 Hengqi Chen   2025-10-02  1319  	/* Only poking bpf text is supported. Since kernel function entry
3d770bd11b94306 Hengqi Chen   2025-10-02  1320  	 * is set up by ftrace, we rely on ftrace to poke kernel functions.
3d770bd11b94306 Hengqi Chen   2025-10-02  1321  	 */
73721d8676771c6 Chenghao Duan 2025-12-31 @1322  	if (!__bpf_address_lookup((unsigned long)ip, &size, &offset, namebuf))
9fbd18cf4c69f51 Chenghao Duan 2025-08-05  1323  		return -ENOTSUPP;
9fbd18cf4c69f51 Chenghao Duan 2025-08-05  1324  
73721d8676771c6 Chenghao Duan 2025-12-31  1325  	image = ip - offset;
73721d8676771c6 Chenghao Duan 2025-12-31  1326  
73721d8676771c6 Chenghao Duan 2025-12-31  1327  	/* zero offset means we're poking bpf prog entry */
73721d8676771c6 Chenghao Duan 2025-12-31  1328  	if (offset == 0) {
73721d8676771c6 Chenghao Duan 2025-12-31  1329  		/* skip to the nop instruction in bpf prog entry:
73721d8676771c6 Chenghao Duan 2025-12-31  1330  		 * move t0, ra
73721d8676771c6 Chenghao Duan 2025-12-31  1331  		 * nop
73721d8676771c6 Chenghao Duan 2025-12-31  1332  		 */
73721d8676771c6 Chenghao Duan 2025-12-31  1333  		ip = image + LOONGARCH_INSN_SIZE;
73721d8676771c6 Chenghao Duan 2025-12-31  1334  	}
73721d8676771c6 Chenghao Duan 2025-12-31  1335  
ae4a3160d19cd16 Menglong Dong 2025-11-18  1336  	is_call = old_t == BPF_MOD_CALL;
9fbd18cf4c69f51 Chenghao Duan 2025-08-05  1337  	ret = emit_jump_or_nops(old_addr, ip, old_insns, is_call);
9fbd18cf4c69f51 Chenghao Duan 2025-08-05  1338  	if (ret)
9fbd18cf4c69f51 Chenghao Duan 2025-08-05  1339  		return ret;
9fbd18cf4c69f51 Chenghao Duan 2025-08-05  1340  
9fbd18cf4c69f51 Chenghao Duan 2025-08-05  1341  	if (memcmp(ip, old_insns, LOONGARCH_LONG_JUMP_NBYTES))
9fbd18cf4c69f51 Chenghao Duan 2025-08-05  1342  		return -EFAULT;
9fbd18cf4c69f51 Chenghao Duan 2025-08-05  1343  
ae4a3160d19cd16 Menglong Dong 2025-11-18  1344  	is_call = new_t == BPF_MOD_CALL;
9fbd18cf4c69f51 Chenghao Duan 2025-08-05  1345  	ret = emit_jump_or_nops(new_addr, ip, new_insns, is_call);
9fbd18cf4c69f51 Chenghao Duan 2025-08-05  1346  	if (ret)
9fbd18cf4c69f51 Chenghao Duan 2025-08-05  1347  		return ret;
9fbd18cf4c69f51 Chenghao Duan 2025-08-05  1348  
9fbd18cf4c69f51 Chenghao Duan 2025-08-05  1349  	mutex_lock(&text_mutex);
9fbd18cf4c69f51 Chenghao Duan 2025-08-05  1350  	if (memcmp(ip, new_insns, LOONGARCH_LONG_JUMP_NBYTES))
9fbd18cf4c69f51 Chenghao Duan 2025-08-05  1351  		ret = larch_insn_text_copy(ip, new_insns, LOONGARCH_LONG_JUMP_NBYTES);
9fbd18cf4c69f51 Chenghao Duan 2025-08-05  1352  	mutex_unlock(&text_mutex);
9fbd18cf4c69f51 Chenghao Duan 2025-08-05  1353  
9fbd18cf4c69f51 Chenghao Duan 2025-08-05  1354  	return ret;
9fbd18cf4c69f51 Chenghao Duan 2025-08-05  1355  }
9fbd18cf4c69f51 Chenghao Duan 2025-08-05  1356  

:::::: The code at line 1322 was first introduced by commit
:::::: 73721d8676771c6c7b06d4e636cc053fc76afefd LoongArch: BPF: Enhance the bpf_arch_text_poke() function

:::::: TO: Chenghao Duan <duanchenghao@kylinos.cn>
:::::: CC: Huacai Chen <chenhuacai@loongson.cn>

-- 
0-DAY CI Kernel Test Service
https://github.com/intel/lkp-tests/wiki