* [bpf-next:master 35/79] kernel/bpf/hashtab.c:1292:14: error: call to undeclared function 'arch_cmpxchg_local'; ISO C99 and later do not support implicit function declarations
@ 2026-10-18 12:06 kernel test robot
0 siblings, 0 replies; only message in thread
From: kernel test robot @ 2026-10-18 12:06 UTC (permalink / raw)
To: Josef Bacik; +Cc: llvm, oe-kbuild-all, Alexei Starovoitov
tree: https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next.git master
head: a6303535c2ad9d49598d52556183911f02287791
commit: ccb88db8dac8fabde58656d5d4a33711e89c480a [35/79] bpf: Don't hand out a linked element as extra element
config: hexagon-randconfig-1001-20261018 (https://download.01.org/0day-ci/archive/20261018/202610182048.aEaiBP8W-lkp@intel.com/config)
compiler: clang version 21.1.8 (https://github.com/llvm/llvm-project 2078da43e25a4623cab2d0d60decddf709aaea28)
reproduce (this is a W=1 build): (https://download.01.org/0day-ci/archive/20261018/202610182048.aEaiBP8W-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/202610182048.aEaiBP8W-lkp@intel.com/
All errors (new ones prefixed by >>):
>> kernel/bpf/hashtab.c:1292:14: error: call to undeclared function 'arch_cmpxchg_local'; ISO C99 and later do not support implicit function declarations [-Wimplicit-function-declaration]
1292 | } while (!try_cmpxchg_local(pl_new, &l_new, NULL));
| ^
include/linux/atomic/atomic-instrumented.h:5022:2: note: expanded from macro 'try_cmpxchg_local'
5022 | raw_try_cmpxchg_local(__ai_ptr, __ai_oldp, __VA_ARGS__); \
| ^
include/linux/atomic/atomic-arch-fallback.h:392:9: note: expanded from macro 'raw_try_cmpxchg_local'
392 | ___r = raw_cmpxchg_local((_ptr), ___o, (_new)); \
| ^
include/linux/atomic/atomic-arch-fallback.h:384:27: note: expanded from macro 'raw_cmpxchg_local'
384 | #define raw_cmpxchg_local arch_cmpxchg_local
| ^
>> kernel/bpf/hashtab.c:1292:14: error: incompatible integer to pointer conversion assigning to 'typeof (*(__ai_ptr))' (aka 'struct htab_elem *') from 'int' [-Wint-conversion]
1292 | } while (!try_cmpxchg_local(pl_new, &l_new, NULL));
| ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
include/linux/atomic/atomic-instrumented.h:5022:2: note: expanded from macro 'try_cmpxchg_local'
5022 | raw_try_cmpxchg_local(__ai_ptr, __ai_oldp, __VA_ARGS__); \
| ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
include/linux/atomic/atomic-arch-fallback.h:392:7: note: expanded from macro 'raw_try_cmpxchg_local'
392 | ___r = raw_cmpxchg_local((_ptr), ___o, (_new)); \
| ^ ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
2 errors generated.
vim +/arch_cmpxchg_local +1292 kernel/bpf/hashtab.c
1268
1269 static struct htab_elem *alloc_htab_elem(struct bpf_htab *htab, void *key,
1270 void *value, u32 key_size, u32 hash,
1271 bool percpu, bool onallcpus,
1272 struct htab_elem *old_elem, u64 map_flags)
1273 {
1274 u32 size = htab->map.value_size;
1275 bool prealloc = htab_is_prealloc(htab);
1276 struct htab_elem *l_new, **pl_new;
1277 void __percpu *pptr;
1278
1279 if (prealloc) {
1280 if (old_elem) {
1281 /* if we're updating the existing element,
1282 * use per-cpu extra elems to avoid freelist_pop/push.
1283 * The caller puts old_elem into the slot once it is
1284 * unlinked. Until then the slot is empty for an NMI
1285 * or a kprobe that updates this map on this cpu.
1286 */
1287 pl_new = this_cpu_ptr(htab->extra_elems);
1288 l_new = READ_ONCE(*pl_new);
1289 do {
1290 if (!l_new)
1291 return ERR_PTR(-EBUSY);
> 1292 } while (!try_cmpxchg_local(pl_new, &l_new, NULL));
1293 } else {
1294 struct pcpu_freelist_node *l;
1295
1296 l = __pcpu_freelist_pop(&htab->freelist);
1297 if (!l)
1298 return ERR_PTR(-E2BIG);
1299 l_new = container_of(l, struct htab_elem, fnode);
1300 bpf_map_inc_elem_count(&htab->map);
1301 }
1302 } else {
1303 void *container;
1304
1305 if (is_map_full(htab))
1306 if (!old_elem)
1307 /* when map is full and update() is replacing
1308 * old element, it's ok to allocate, since
1309 * old element will be freed immediately.
1310 * Otherwise return an error
1311 */
1312 return ERR_PTR(-E2BIG);
1313 inc_elem_count(htab);
1314 container = bpf_mem_cache_alloc(&htab->ma);
1315 if (!container) {
1316 l_new = ERR_PTR(-ENOMEM);
1317 goto dec_count;
1318 }
1319 l_new = container + htab->elem_offset;
1320 }
1321
1322 if (htab_has_hash(htab))
1323 memcpy(l_new->key, key, key_size);
1324
1325 if (percpu) {
1326 if (prealloc) {
1327 pptr = htab_elem_get_ptr(l_new, key_size);
1328 } else {
1329 /* alloc_percpu zero-fills */
1330 void *ptr = bpf_mem_cache_alloc(&htab->pcpu_ma);
1331
1332 if (!ptr) {
1333 bpf_mem_cache_free(&htab->ma, htab_elem_container(htab, l_new));
1334 l_new = ERR_PTR(-ENOMEM);
1335 goto dec_count;
1336 }
1337 htab_elem_set_ptr_to_pptr(htab, l_new, ptr);
1338 pptr = *(void __percpu **)ptr;
1339 }
1340
1341 pcpu_init_value(htab, pptr, value, onallcpus, map_flags);
1342
1343 if (!prealloc)
1344 htab_elem_set_ptr(l_new, key_size, pptr);
1345 } else if (fd_htab_map_needs_adjust(htab)) {
1346 size = round_up(size, 8);
1347 memcpy(htab_elem_value(l_new, key_size), value, size);
1348 } else if (map_flags & BPF_F_LOCK) {
1349 copy_map_value_locked(&htab->map,
1350 htab_elem_value(l_new, key_size),
1351 value, false);
1352 } else {
1353 copy_map_value(&htab->map, htab_elem_value(l_new, key_size), value);
1354 }
1355
1356 if (htab_has_hash(htab))
1357 htab_elem_set_hash(l_new, hash);
1358 else
1359 WRITE_ONCE(*(unsigned long *)l_new->key,
1360 htab_zero_extend_key(key, key_size));
1361 return l_new;
1362 dec_count:
1363 dec_elem_count(htab);
1364 return l_new;
1365 }
1366
--
0-DAY CI Kernel Test Service
https://github.com/intel/lkp-tests/wiki
^ permalink raw reply [flat|nested] only message in thread
only message in thread, other threads:[~2026-10-18 12:06 UTC | newest]
Thread overview: (only message) (download: mbox.gz follow: Atom feed
-- links below jump to the message on this page --
2026-10-18 12:06 [bpf-next:master 35/79] kernel/bpf/hashtab.c:1292:14: error: call to undeclared function 'arch_cmpxchg_local'; ISO C99 and later do not support implicit function declarations kernel test robot
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox