Hi Taehee, Thank you for the patch! Perhaps something to improve: [auto build test WARNING on net-next/master] url: https://github.com/0day-ci/linux/commits/Taehee-Yoo/mld-change-context-fr... base: https://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next.git 3c5a2fd042d0bfac71a2dfb99515723d318df47b config: x86_64-randconfig-s022-20210214 (attached as .config) compiler: gcc-9 (Debian 9.3.0-15) 9.3.0 reproduce: # apt-get install sparse # sparse version: v0.6.3-215-g0fb77bb6-dirty # https://github.com/0day-ci/linux/commit/5a21fa32b1401aa428cd0249ee5b02ddb... git remote add linux-review https://github.com/0day-ci/linux git fetch --no-tags linux-review Taehee-Yoo/mld-change-context-from-atomic-to-sleepable/20210214-015930 git checkout 5a21fa32b1401aa428cd0249ee5b02ddb12cff60 # save the attached .config to linux build tree make W=1 C=1 CF='-fdiagnostic-prefix -D__CHECK_ENDIAN__' ARCH=x86_64 If you fix the issue, kindly add following tag as appropriate Reported-by: kernel test robot <lkp(a)intel.com&gt; "sparse warnings: (new ones prefixed by >>)" >> net/ipv6/mcast.c:430:17: sparse: sparse: incompatible types in comparison expression (different address spaces): >> net/ipv6/mcast.c:430:17: sparse: struct ip6_sf_socklist [noderef] __rcu * >> net/ipv6/mcast.c:430:17: sparse: struct ip6_sf_socklist * net/ipv6/mcast.c: note: in included file: include/net/mld.h:32:43: sparse: sparse: array of flexible structures net/ipv6/mcast.c:257:25: sparse: sparse: context imbalance in 'ip6_mc_find_dev_rcu' - different lock contexts for basic block net/ipv6/mcast.c:447:9: sparse: sparse: context imbalance in 'ip6_mc_source' - unexpected unlock net/ipv6/mcast.c:536:9: sparse: sparse: context imbalance in 'ip6_mc_msfilter' - unexpected unlock net/ipv6/mcast.c:583:21: sparse: sparse: context imbalance in 'ip6_mc_msfget' - unexpected unlock net/ipv6/mcast.c:2724:25: sparse: sparse: context imbalance in 'igmp6_mc_get_next' - unexpected unlock net/ipv6/mcast.c:2746:9: sparse: sparse: context imbalance in 'igmp6_mc_get_idx' - wrong count at exit net/ipv6/mcast.c:2773:9: sparse: sparse: context imbalance in 'igmp6_mc_seq_stop' - unexpected unlock net/ipv6/mcast.c:2845:31: sparse: sparse: context imbalance in 'igmp6_mcf_get_next' - unexpected unlock net/ipv6/mcast.c:2877:9: sparse: sparse: context imbalance in 'igmp6_mcf_get_idx' - wrong count at exit net/ipv6/mcast.c:2894:9: sparse: sparse: context imbalance in 'igmp6_mcf_seq_next' - wrong count at exit net/ipv6/mcast.c:2907:17: sparse: sparse: context imbalance in 'igmp6_mcf_seq_stop' - unexpected unlock vim +430 net/ipv6/mcast.c 325 326 int ip6_mc_source(int add, int omode, struct sock *sk, 327 struct group_source_req *pgsr) 328 { 329 struct in6_addr *source, *group; 330 struct ipv6_mc_socklist *pmc; 331 struct inet6_dev *idev; 332 struct ipv6_pinfo *inet6 = inet6_sk(sk); 333 struct ip6_sf_socklist *psl; 334 struct net *net = sock_net(sk); 335 int i, j, rv; 336 int leavegroup = 0; 337 int err; 338 339 source = &((struct sockaddr_in6 *)&pgsr->gsr_source)->sin6_addr; 340 group = &((struct sockaddr_in6 *)&pgsr->gsr_group)->sin6_addr; 341 342 if (!ipv6_addr_is_multicast(group)) 343 return -EINVAL; 344 345 rcu_read_lock(); 346 idev = ip6_mc_find_dev_rcu(net, group, pgsr->gsr_interface); 347 if (!idev) { 348 rcu_read_unlock(); 349 return -ENODEV; 350 } 351 352 err = -EADDRNOTAVAIL; 353 354 for_each_pmc_rcu(inet6, pmc) { 355 if (pgsr->gsr_interface && pmc->ifindex != pgsr->gsr_interface) 356 continue; 357 if (ipv6_addr_equal(&pmc->addr, group)) 358 break; 359 } 360 if (!pmc) { /* must have a prior join */ 361 err = -EINVAL; 362 goto done; 363 } 364 /* if a source filter was set, must be the same mode as before */ 365 if (rcu_access_pointer(pmc->sflist)) { 366 if (pmc->sfmode != omode) { 367 err = -EINVAL; 368 goto done; 369 } 370 } else if (pmc->sfmode != omode) { 371 /* allow mode switches for empty-set filters */ 372 ip6_mc_add_src(idev, group, omode, 0, NULL, 0); 373 ip6_mc_del_src(idev, group, pmc->sfmode, 0, NULL, 0); 374 pmc->sfmode = omode; 375 } 376 377 psl = rtnl_dereference(pmc->sflist); 378 if (!add) { 379 if (!psl) 380 goto done; /* err = -EADDRNOTAVAIL */ 381 rv = !0; 382 for (i = 0; i < psl->sl_count; i++) { 383 rv = !ipv6_addr_equal(&psl->sl_addr[i], source); 384 if (rv == 0) 385 break; 386 } 387 if (rv) /* source not found */ 388 goto done; /* err = -EADDRNOTAVAIL */ 389 390 /* special case - (INCLUDE, empty) == LEAVE_GROUP */ 391 if (psl->sl_count == 1 && omode == MCAST_INCLUDE) { 392 leavegroup = 1; 393 goto done; 394 } 395 396 /* update the interface filter */ 397 ip6_mc_del_src(idev, group, omode, 1, source, 1); 398 399 for (j = i+1; j < psl->sl_count; j++) 400 psl->sl_addr[j-1] = psl->sl_addr[j]; 401 psl->sl_count--; 402 err = 0; 403 goto done; 404 } 405 /* else, add a new source to the filter */ 406 407 if (psl && psl->sl_count >= sysctl_mld_max_msf) { 408 err = -ENOBUFS; 409 goto done; 410 } 411 if (!psl || psl->sl_count == psl->sl_max) { 412 struct ip6_sf_socklist *newpsl; 413 int count = IP6_SFBLOCK; 414 415 if (psl) 416 count += psl->sl_max; 417 newpsl = sock_kmalloc(sk, IP6_SFLSIZE(count), GFP_ATOMIC); 418 if (!newpsl) { 419 err = -ENOBUFS; 420 goto done; 421 } 422 newpsl->sl_max = count; 423 newpsl->sl_count = count - IP6_SFBLOCK; 424 if (psl) { 425 for (i = 0; i < psl->sl_count; i++) 426 newpsl->sl_addr[i] = psl->sl_addr[i]; 427 atomic_sub(IP6_SFLSIZE(psl->sl_max), &sk->sk_omem_alloc); 428 kfree_rcu(psl, rcu); 429 } > 430 rcu_assign_pointer(psl, newpsl); 431 rcu_assign_pointer(pmc->sflist, psl); 432 } 433 rv = 1; /* > 0 for insert logic below if sl_count is 0 */ 434 for (i = 0; i < psl->sl_count; i++) { 435 rv = !ipv6_addr_equal(&psl->sl_addr[i], source); 436 if (rv == 0) /* There is an error in the address. */ 437 goto done; 438 } 439 for (j = psl->sl_count-1; j >= i; j--) 440 psl->sl_addr[j+1] = psl->sl_addr[j]; 441 psl->sl_addr[i] = *source; 442 psl->sl_count++; 443 err = 0; 444 /* update the interface list */ 445 ip6_mc_add_src(idev, group, omode, 1, source, 1); 446 done: 447 read_unlock_bh(&idev->lock); 448 rcu_read_unlock(); 449 if (leavegroup) 450 err = ipv6_sock_mc_drop(sk, pgsr->gsr_interface, group); 451 return err; 452 } 453 --- 0-DAY CI Kernel Test Service, Intel Corporation https://lists.01.org/hyperkitty/list/kbuild-all@lists.01.org