tree: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git master head: 449dc8c97089a6e09fb2dac4d92b1b7ac0eb7c1e commit: a271a89c6e4773478b1c4f8213dfe8351ea66723 dm mpath: take m->lock spinlock when testing QUEUE_IF_NO_PATH 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:1682 multipath_end_io_bio() error: double unlocked 'm->lock' (orig line 1675) drivers/md/dm-mpath.c:1988 multipath_prepare_ioctl() error: double unlocked 'm->lock' (orig line 1977) Old smatch warnings: drivers/md/dm-mpath.c:432 choose_pgpath() error: double unlocked 'm->lock' (orig line 402) 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 +1682 drivers/md/dm-mpath.c ^1da177e4c3f41 Linus Torvalds 2005-04-16 1647 4e4cbee93d5613 Christoph Hellwig 2017-06-03 1648 static int multipath_end_io_bio(struct dm_target *ti, struct bio *clone, 4e4cbee93d5613 Christoph Hellwig 2017-06-03 1649 blk_status_t *error) 76e33fe4e2c436 Mike Snitzer 2016-05-19 1650 { 14ef1e48269dde Christoph Hellwig 2017-06-03 1651 struct multipath *m = ti->private; 14ef1e48269dde Christoph Hellwig 2017-06-03 1652 struct dm_mpath_io *mpio = get_mpio_from_bio(clone); 14ef1e48269dde Christoph Hellwig 2017-06-03 1653 struct pgpath *pgpath = mpio->pgpath; 76e33fe4e2c436 Mike Snitzer 2016-05-19 1654 unsigned long flags; 1be56909845889 Christoph Hellwig 2017-06-03 1655 int r = DM_ENDIO_DONE; 76e33fe4e2c436 Mike Snitzer 2016-05-19 1656 a1275677f8cd06 Keith Busch 2018-01-09 1657 if (!*error || !blk_path_error(*error)) 14ef1e48269dde Christoph Hellwig 2017-06-03 1658 goto done; 76e33fe4e2c436 Mike Snitzer 2016-05-19 1659 14ef1e48269dde Christoph Hellwig 2017-06-03 1660 if (pgpath) 14ef1e48269dde Christoph Hellwig 2017-06-03 1661 fail_path(pgpath); 76e33fe4e2c436 Mike Snitzer 2016-05-19 1662 a271a89c6e4773 Mike Snitzer 2020-06-10 1663 if (!atomic_read(&m->nr_valid_paths)) { a271a89c6e4773 Mike Snitzer 2020-06-10 1664 spin_lock_irqsave(&m->lock, flags); a271a89c6e4773 Mike Snitzer 2020-06-10 1665 if (!test_bit(MPATHF_QUEUE_IF_NO_PATH, &m->flags)) { a862e4e2154289 Mike Snitzer 2020-05-26 1666 if (__must_push_back(m)) { c1fd0abee0d52e Mike Snitzer 2017-12-07 1667 r = DM_ENDIO_REQUEUE; c1fd0abee0d52e Mike Snitzer 2017-12-07 1668 } else { 18a482f5245cc8 Christoph Hellwig 2017-05-15 1669 dm_report_EIO(m); 4e4cbee93d5613 Christoph Hellwig 2017-06-03 1670 *error = BLK_STS_IOERR; c1fd0abee0d52e Mike Snitzer 2017-12-07 1671 } a271a89c6e4773 Mike Snitzer 2020-06-10 1672 spin_unlock_irqrestore(&m->lock, flags); 14ef1e48269dde Christoph Hellwig 2017-06-03 1673 goto done; 18a482f5245cc8 Christoph Hellwig 2017-05-15 1674 } a271a89c6e4773 Mike Snitzer 2020-06-10 @1675 spin_unlock_irqrestore(&m->lock, flags); a271a89c6e4773 Mike Snitzer 2020-06-10 1676 } 76e33fe4e2c436 Mike Snitzer 2016-05-19 1677 76e33fe4e2c436 Mike Snitzer 2016-05-19 1678 spin_lock_irqsave(&m->lock, flags); 76e33fe4e2c436 Mike Snitzer 2016-05-19 1679 bio_list_add(&m->queued_bios, clone); 76e33fe4e2c436 Mike Snitzer 2016-05-19 1680 if (!test_bit(MPATHF_QUEUE_IO, &m->flags)) 76e33fe4e2c436 Mike Snitzer 2016-05-19 1681 queue_work(kmultipathd, &m->process_queued_bios); 69cea0d45a618a Mike Snitzer 2020-06-10 @1682 spin_unlock_irqrestore(&m->lock, flags); 76e33fe4e2c436 Mike Snitzer 2016-05-19 1683 1be56909845889 Christoph Hellwig 2017-06-03 1684 r = DM_ENDIO_INCOMPLETE; 14ef1e48269dde Christoph Hellwig 2017-06-03 1685 done: 76e33fe4e2c436 Mike Snitzer 2016-05-19 1686 if (pgpath) { 14ef1e48269dde Christoph Hellwig 2017-06-03 1687 struct path_selector *ps = &pgpath->pg->ps; 14ef1e48269dde Christoph Hellwig 2017-06-03 1688 76e33fe4e2c436 Mike Snitzer 2016-05-19 1689 if (ps->type->end_io) 087615bf3acdaf Gabriel Krisman Bertazi 2020-04-30 1690 ps->type->end_io(ps, &pgpath->path, mpio->nr_bytes, 087615bf3acdaf Gabriel Krisman Bertazi 2020-04-30 1691 dm_start_time_ns_from_clone(clone)); 76e33fe4e2c436 Mike Snitzer 2016-05-19 1692 } 76e33fe4e2c436 Mike Snitzer 2016-05-19 1693 1be56909845889 Christoph Hellwig 2017-06-03 1694 return r; 76e33fe4e2c436 Mike Snitzer 2016-05-19 1695 } 76e33fe4e2c436 Mike Snitzer 2016-05-19 1696 :::::: The code at line 1682 was first introduced by commit :::::: 69cea0d45a618ad4ae74f36386ef1af5128b2b19 dm mpath: changes from initial m->flags locking audit :::::: TO: Mike Snitzer <snitzer(a)redhat.com&gt; :::::: CC: Mike Snitzer <snitzer(a)redhat.com&gt; --- 0-DAY CI Kernel Test Service, Intel Corporation https://lists.01.org/hyperkitty/list/kbuild-all@lists.01.org