tree: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git master head: 449dc8c97089a6e09fb2dac4d92b1b7ac0eb7c1e commit: 69cea0d45a618ad4ae74f36386ef1af5128b2b19 dm mpath: changes from initial m->flags locking audit date: 4 weeks ago config: arm-randconfig-m031-20200808 (attached as .config) compiler: arm-linux-gnueabi-gcc (GCC) 9.3.0 If you fix the issue, kindly add following tag as appropriate Reported-by: kernel test robot <lkp(a)intel.com&gt; New smatch warnings: drivers/md/dm-mpath.c:432 choose_pgpath() error: double unlocked 'm->lock' (orig line 402) Old smatch warnings: drivers/md/dm-mpath.c:443 choose_pgpath() error: double unlocked 'm->lock' (orig line 389) drivers/md/dm-mpath.c:593 __map_bio() error: double unlocked 'm->lock' (orig line 589) drivers/md/dm-mpath.c:1574 pg_init_done() error: double unlocked 'm->lock' (orig line 1527) vim +432 drivers/md/dm-mpath.c 378 379 static struct pgpath *choose_pgpath(struct multipath *m, size_t nr_bytes) 380 { 381 unsigned long flags; 382 struct priority_group *pg; 383 struct pgpath *pgpath; 384 unsigned bypassed = 1; 385 386 if (!atomic_read(&m->nr_valid_paths)) { 387 spin_lock_irqsave(&m->lock, flags); 388 clear_bit(MPATHF_QUEUE_IO, &m->flags); 389 spin_unlock_irqrestore(&m->lock, flags); 390 goto failed; 391 } 392 393 /* Were we instructed to switch PG? */ 394 if (READ_ONCE(m->next_pg)) { 395 spin_lock_irqsave(&m->lock, flags); 396 pg = m->next_pg; 397 if (!pg) { 398 spin_unlock_irqrestore(&m->lock, flags); 399 goto check_current_pg; 400 } 401 m->next_pg = NULL; 403 pgpath = choose_path_in_pg(m, pg, nr_bytes); 404 if (!IS_ERR_OR_NULL(pgpath)) 405 return pgpath; 406 } 407 408 /* Don't change PG until it has no remaining paths */ 409 check_current_pg: 410 pg = READ_ONCE(m->current_pg); 411 if (pg) { 412 pgpath = choose_path_in_pg(m, pg, nr_bytes); 413 if (!IS_ERR_OR_NULL(pgpath)) 414 return pgpath; 415 } 416 417 /* 418 * Loop through priority groups until we find a valid path. 419 * First time we skip PGs marked 'bypassed'. 420 * Second time we only try the ones we skipped, but set 421 * pg_init_delay_retry so we do not hammer controllers. 422 */ 423 do { 424 list_for_each_entry(pg, &m->priority_groups, list) { 425 if (pg->bypassed == !!bypassed) 426 continue; 427 pgpath = choose_path_in_pg(m, pg, nr_bytes); 428 if (!IS_ERR_OR_NULL(pgpath)) { 429 if (!bypassed) { 430 spin_lock_irqsave(&m->lock, flags); 431 set_bit(MPATHF_PG_INIT_DELAY_RETRY, &m->flags); 433 } 434 return pgpath; 435 } 436 } 437 } while (bypassed--); 438 439 failed: 440 spin_lock_irqsave(&m->lock, flags); 441 m->current_pgpath = NULL; 442 m->current_pg = NULL; 443 spin_unlock_irqrestore(&m->lock, flags); 444 445 return NULL; 446 } 447 --- 0-DAY CI Kernel Test Service, Intel Corporation https://lists.01.org/hyperkitty/list/kbuild-all@lists.01.org