Dev loop5: unable to read RDB block 1
 loop5: AHDI p1 p2
loop5: partition table partially beyond EOD, truncated
loop5: p1 start 4278648832 is beyond EOD, truncated
INFO: task kworker/u4:5:4725 blocked for more than 140 seconds.
      Not tainted 4.9.123-g520d10d3 #29
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
kworker/u4:5    D25736  4725      2 0x00000000
Workqueue: netns cleanup_net
 ffff8801caafe000 ffff88019e682a00 ffff8801c795e4c0 ffff8801c6dfe000
 ffff8801db321c18 ffff8801ceca7770 ffffffff839f0ebd ffff8801ceca7710
 ffffffff81f2125c ffff8801ceca7828 00ffffff812306aa ffff8801db3224e8
Call Trace:
 [<ffffffff839f24bf>] schedule+0x7f/0x1b0 kernel/sched/core.c:3553
 [<ffffffff839fe8d1>] schedule_timeout+0x861/0xf70 kernel/time/timer.c:1768
 [<ffffffff839f5683>] do_wait_for_common kernel/sched/completion.c:75 [inline]
 [<ffffffff839f5683>] __wait_for_common kernel/sched/completion.c:93 [inline]
 [<ffffffff839f5683>] wait_for_common kernel/sched/completion.c:101 [inline]
 [<ffffffff839f5683>] wait_for_completion+0x203/0x2e0 kernel/sched/completion.c:122
 [<ffffffff811a00c6>] kthread_stop+0xa6/0x5d0 kernel/kthread.c:519
 [<ffffffff830ff3fe>] pg_net_exit+0x3de/0x6e0 net/core/pktgen.c:3923
 [<ffffffff83060f20>] ops_exit_list.isra.6+0xb0/0x160 net/core/net_namespace.c:136
 [<ffffffff83063df1>] cleanup_net+0x321/0x630 net/core/net_namespace.c:473
 [<ffffffff8118f461>] process_one_work+0x7e1/0x1500 kernel/workqueue.c:2092
 [<ffffffff81190256>] worker_thread+0xd6/0x10a0 kernel/workqueue.c:2226
 [<ffffffff8119f3cd>] kthread+0x26d/0x300 kernel/kthread.c:211
 [<ffffffff83a01f5c>] ret_from_fork+0x5c/0x70 arch/x86/entry/entry_64.S:373

Showing all locks held in the system:
2 locks held by kworker/u4:0/6:
 #0:  ("events_unbound"){.+.+.+}, at: [<ffffffff8118f36e>] work_static include/linux/workqueue.h:186 [inline]
 #0:  ("events_unbound"){.+.+.+}, at: [<ffffffff8118f36e>] set_work_data kernel/workqueue.c:617 [inline]
 #0:  ("events_unbound"){.+.+.+}, at: [<ffffffff8118f36e>] set_work_pool_and_clear_pending kernel/workqueue.c:644 [inline]
 #0:  ("events_unbound"){.+.+.+}, at: [<ffffffff8118f36e>] process_one_work+0x6ee/0x1500 kernel/workqueue.c:2085
 #1:  ((&sub_info->work)){+.+.+.}, at: [<ffffffff8118f3a8>] process_one_work+0x728/0x1500 kernel/workqueue.c:2089
2 locks held by kworker/u4:1/22:
 #0:  ("events_unbound"){.+.+.+}, at: [<ffffffff8118f36e>] work_static include/linux/workqueue.h:186 [inline]
 #0:  ("events_unbound"){.+.+.+}, at: [<ffffffff8118f36e>] set_work_data kernel/workqueue.c:617 [inline]
 #0:  ("events_unbound"){.+.+.+}, at: [<ffffffff8118f36e>] set_work_pool_and_clear_pending kernel/workqueue.c:644 [inline]
 #0:  ("events_unbound"){.+.+.+}, at: [<ffffffff8118f36e>] process_one_work+0x6ee/0x1500 kernel/workqueue.c:2085
 #1:  ((&sub_info->work)){+.+.+.}, at: [<ffffffff8118f3a8>] process_one_work+0x728/0x1500 kernel/workqueue.c:2089
1 lock held by kworker/dying/24:
 #0:  ((task_exit_notifier).rwsem){.+.+..}, at: [<ffffffff811a5138>] __blocking_notifier_call_chain kernel/notifier.c:316 [inline]
 #0:  ((task_exit_notifier).rwsem){.+.+..}, at: [<ffffffff811a5138>] blocking_notifier_call_chain+0x68/0xa0 kernel/notifier.c:328
2 locks held by kworker/u4:2/157:
 #0:  ("events_unbound"){.+.+.+}, at: [<ffffffff8118f36e>] work_static include/linux/workqueue.h:186 [inline]
 #0:  ("events_unbound"){.+.+.+}, at: [<ffffffff8118f36e>] set_work_data kernel/workqueue.c:617 [inline]
 #0:  ("events_unbound"){.+.+.+}, at: [<ffffffff8118f36e>] set_work_pool_and_clear_pending kernel/workqueue.c:644 [inline]
 #0:  ("events_unbound"){.+.+.+}, at: [<ffffffff8118f36e>] process_one_work+0x6ee/0x1500 kernel/workqueue.c:2085
 #1:  ((&sub_info->work)){+.+.+.}, at: [<ffffffff8118f3a8>] process_one_work+0x728/0x1500 kernel/workqueue.c:2089
2 locks held by khungtaskd/519:
 #0:  (rcu_read_lock){......}, at: [<ffffffff81368a9c>] check_hung_uninterruptible_tasks kernel/hung_task.c:168 [inline]
 #0:  (rcu_read_lock){......}, at: [<ffffffff81368a9c>] watchdog+0x11c/0xa20 kernel/hung_task.c:239
 #1:  (tasklist_lock){.+.?..}, at: [<ffffffff81428308>] debug_show_all_locks+0x79/0x218 kernel/locking/lockdep.c:4336
2 locks held by kworker/u4:3/1676:
 #0:  ("events_unbound"){.+.+.+}, at: [<ffffffff8118f36e>] work_static include/linux/workqueue.h:186 [inline]
 #0:  ("events_unbound"){.+.+.+}, at: [<ffffffff8118f36e>] set_work_data kernel/workqueue.c:617 [inline]
 #0:  ("events_unbound"){.+.+.+}, at: [<ffffffff8118f36e>] set_work_pool_and_clear_pending kernel/workqueue.c:644 [inline]
 #0:  ("events_unbound"){.+.+.+}, at: [<ffffffff8118f36e>] process_one_work+0x6ee/0x1500 kernel/workqueue.c:2085
 #1:  ((&sub_info->work)){+.+.+.}, at: [<ffffffff8118f3a8>] process_one_work+0x728/0x1500 kernel/workqueue.c:2089
2 locks held by getty/3695:
 #0:  (&tty->ldisc_sem){++++++}, at: [<ffffffff839fff62>] ldsem_down_read+0x32/0x40 drivers/tty/tty_ldsem.c:367
 #1:  (&ldata->atomic_read_lock){+.+...}, at: [<ffffffff821253c2>] n_tty_read+0x202/0x16e0 drivers/tty/n_tty.c:2142
1 lock held by syz-executor5/3785:
 #0:  ((task_exit_notifier).rwsem){.+.+..}, at: [<ffffffff811a5138>] __blocking_notifier_call_chain kernel/notifier.c:316 [inline]
 #0:  ((task_exit_notifier).rwsem){.+.+..}, at: [<ffffffff811a5138>] blocking_notifier_call_chain+0x68/0xa0 kernel/notifier.c:328
1 lock held by syz-executor0/3789:
 #0:  ((task_exit_notifier).rwsem){.+.+..}, at: [<ffffffff811a5138>] __blocking_notifier_call_chain kernel/notifier.c:316 [inline]
 #0:  ((task_exit_notifier).rwsem){.+.+..}, at: [<ffffffff811a5138>] blocking_notifier_call_chain+0x68/0xa0 kernel/notifier.c:328
2 locks held by kworker/u4:4/4027:
 #0:  ("events_unbound"){.+.+.+}, at: [<ffffffff8118f36e>] work_static include/linux/workqueue.h:186 [inline]
 #0:  ("events_unbound"){.+.+.+}, at: [<ffffffff8118f36e>] set_work_data kernel/workqueue.c:617 [inline]
 #0:  ("events_unbound"){.+.+.+}, at: [<ffffffff8118f36e>] set_work_pool_and_clear_pending kernel/workqueue.c:644 [inline]
 #0:  ("events_unbound"){.+.+.+}, at: [<ffffffff8118f36e>] process_one_work+0x6ee/0x1500 kernel/workqueue.c:2085
 #1:  ((&sub_info->work)){+.+.+.}, at: [<ffffffff8118f3a8>] process_one_work+0x728/0x1500 kernel/workqueue.c:2089
3 locks held by kworker/u4:5/4725:
 #0:  ("%s""netns"){.+.+.+}, at: [<ffffffff8118f36e>] work_static include/linux/workqueue.h:186 [inline]
 #0:  ("%s""netns"){.+.+.+}, at: [<ffffffff8118f36e>] set_work_data kernel/workqueue.c:617 [inline]
 #0:  ("%s""netns"){.+.+.+}, at: [<ffffffff8118f36e>] set_work_pool_and_clear_pending kernel/workqueue.c:644 [inline]
 #0:  ("%s""netns"){.+.+.+}, at: [<ffffffff8118f36e>] process_one_work+0x6ee/0x1500 kernel/workqueue.c:2085
 #1:  (net_cleanup_work){+.+.+.}, at: [<ffffffff8118f3a8>] process_one_work+0x728/0x1500 kernel/workqueue.c:2089
 #2:  (net_mutex){+.+.+.}, at: [<ffffffff83063c0f>] cleanup_net+0x13f/0x630 net/core/net_namespace.c:439
2 locks held by kworker/u4:7/5330:
 #0:  ("events_unbound"){.+.+.+}, at: [<ffffffff8118f36e>] work_static include/linux/workqueue.h:186 [inline]
 #0:  ("events_unbound"){.+.+.+}, at: [<ffffffff8118f36e>] set_work_data kernel/workqueue.c:617 [inline]
 #0:  ("events_unbound"){.+.+.+}, at: [<ffffffff8118f36e>] set_work_pool_and_clear_pending kernel/workqueue.c:644 [inline]
 #0:  ("events_unbound"){.+.+.+}, at: [<ffffffff8118f36e>] process_one_work+0x6ee/0x1500 kernel/workqueue.c:2085
 #1:  ((&sub_info->work)){+.+.+.}, at: [<ffffffff8118f3a8>] process_one_work+0x728/0x1500 kernel/workqueue.c:2089
1 lock held by syz-executor4/7664:
 #0:  ((task_exit_notifier).rwsem){.+.+..}, at: [<ffffffff811a5138>] __blocking_notifier_call_chain kernel/notifier.c:316 [inline]
 #0:  ((task_exit_notifier).rwsem){.+.+..}, at: [<ffffffff811a5138>] blocking_notifier_call_chain+0x68/0xa0 kernel/notifier.c:328
1 lock held by syz-executor1/13500:
 #0:  ((task_exit_notifier).rwsem){.+.+..}, at: [<ffffffff811a5138>] __blocking_notifier_call_chain kernel/notifier.c:316 [inline]
 #0:  ((task_exit_notifier).rwsem){.+.+..}, at: [<ffffffff811a5138>] blocking_notifier_call_chain+0x68/0xa0 kernel/notifier.c:328
2 locks held by kworker/u4:8/15346:
 #0:  ("events_unbound"){.+.+.+}, at: [<ffffffff8118f36e>] work_static include/linux/workqueue.h:186 [inline]
 #0:  ("events_unbound"){.+.+.+}, at: [<ffffffff8118f36e>] set_work_data kernel/workqueue.c:617 [inline]
 #0:  ("events_unbound"){.+.+.+}, at: [<ffffffff8118f36e>] set_work_pool_and_clear_pending kernel/workqueue.c:644 [inline]
 #0:  ("events_unbound"){.+.+.+}, at: [<ffffffff8118f36e>] process_one_work+0x6ee/0x1500 kernel/workqueue.c:2085
 #1:  ((&sub_info->work)){+.+.+.}, at: [<ffffffff8118f3a8>] process_one_work+0x728/0x1500 kernel/workqueue.c:2089
1 lock held by syz-executor6/16768:
 #0:  ((task_exit_notifier).rwsem){.+.+..}, at: [<ffffffff811a5138>] __blocking_notifier_call_chain kernel/notifier.c:316 [inline]
 #0:  ((task_exit_notifier).rwsem){.+.+..}, at: [<ffffffff811a5138>] blocking_notifier_call_chain+0x68/0xa0 kernel/notifier.c:328
2 locks held by kworker/u4:9/19164:
 #0:  ("events_unbound"){.+.+.+}, at: [<ffffffff8118f36e>] work_static include/linux/workqueue.h:186 [inline]
 #0:  ("events_unbound"){.+.+.+}, at: [<ffffffff8118f36e>] set_work_data kernel/workqueue.c:617 [inline]
 #0:  ("events_unbound"){.+.+.+}, at: [<ffffffff8118f36e>] set_work_pool_and_clear_pending kernel/workqueue.c:644 [inline]
 #0:  ("events_unbound"){.+.+.+}, at: [<ffffffff8118f36e>] process_one_work+0x6ee/0x1500 kernel/workqueue.c:2085
 #1:  ((&sub_info->work)){+.+.+.}, at: [<ffffffff8118f3a8>] process_one_work+0x728/0x1500 kernel/workqueue.c:2089
1 lock held by syz-executor7/19517:
 #0:  ((task_exit_notifier).rwsem){.+.+..}, at: [<ffffffff811a5138>] __blocking_notifier_call_chain kernel/notifier.c:316 [inline]
 #0:  ((task_exit_notifier).rwsem){.+.+..}, at: [<ffffffff811a5138>] blocking_notifier_call_chain+0x68/0xa0 kernel/notifier.c:328
1 lock held by syz-executor3/23576:
 #0:  ((task_exit_notifier).rwsem){.+.+..}, at: [<ffffffff811a5138>] __blocking_notifier_call_chain kernel/notifier.c:316 [inline]
 #0:  ((task_exit_notifier).rwsem){.+.+..}, at: [<ffffffff811a5138>] blocking_notifier_call_chain+0x68/0xa0 kernel/notifier.c:328
1 lock held by syz-executor2/24249:
 #0:  ((task_exit_notifier).rwsem){.+.+..}, at: [<ffffffff811a5138>] __blocking_notifier_call_chain kernel/notifier.c:316 [inline]
 #0:  ((task_exit_notifier).rwsem){.+.+..}, at: [<ffffffff811a5138>] blocking_notifier_call_chain+0x68/0xa0 kernel/notifier.c:328
1 lock held by kpktgend_0/28058:
 #0:  ((task_exit_notifier).rwsem){.+.+..}, at: [<ffffffff811a5138>] __blocking_notifier_call_chain kernel/notifier.c:316 [inline]
 #0:  ((task_exit_notifier).rwsem){.+.+..}, at: [<ffffffff811a5138>] blocking_notifier_call_chain+0x68/0xa0 kernel/notifier.c:328
1 lock held by kpktgend_1/28059:
 #0:  ((task_exit_notifier).rwsem){.+.+..}, at: [<ffffffff811a5138>] __blocking_notifier_call_chain kernel/notifier.c:316 [inline]
 #0:  ((task_exit_notifier).rwsem){.+.+..}, at: [<ffffffff811a5138>] blocking_notifier_call_chain+0x68/0xa0 kernel/notifier.c:328
1 lock held by syz-executor1/28119:
 #0:  ((task_exit_notifier).rwsem){.+.+..}, at: [<ffffffff811a5138>] __blocking_notifier_call_chain kernel/notifier.c:316 [inline]
 #0:  ((task_exit_notifier).rwsem){.+.+..}, at: [<ffffffff811a5138>] blocking_notifier_call_chain+0x68/0xa0 kernel/notifier.c:328
1 lock held by syz-executor1/28124:
 #0:  ((task_exit_notifier).rwsem){.+.+..}, at: [<ffffffff811a5138>] __blocking_notifier_call_chain kernel/notifier.c:316 [inline]
 #0:  ((task_exit_notifier).rwsem){.+.+..}, at: [<ffffffff811a5138>] blocking_notifier_call_chain+0x68/0xa0 kernel/notifier.c:328
1 lock held by syz-executor1/28133:
 #0:  ((task_exit_notifier).rwsem){.+.+..}, at: [<ffffffff811a5138>] __blocking_notifier_call_chain kernel/notifier.c:316 [inline]
 #0:  ((task_exit_notifier).rwsem){.+.+..}, at: [<ffffffff811a5138>] blocking_notifier_call_chain+0x68/0xa0 kernel/notifier.c:328
1 lock held by syz-executor1/28144:
 #0:  ((task_exit_notifier).rwsem){.+.+..}, at: [<ffffffff811a5138>] __blocking_notifier_call_chain kernel/notifier.c:316 [inline]
 #0:  ((task_exit_notifier).rwsem){.+.+..}, at: [<ffffffff811a5138>] blocking_notifier_call_chain+0x68/0xa0 kernel/notifier.c:328
1 lock held by syz-executor1/28190:
 #0:  ((task_exit_notifier).rwsem){.+.+..}, at: [<ffffffff811a5138>] __blocking_notifier_call_chain kernel/notifier.c:316 [inline]
 #0:  ((task_exit_notifier).rwsem){.+.+..}, at: [<ffffffff811a5138>] blocking_notifier_call_chain+0x68/0xa0 kernel/notifier.c:328
1 lock held by syz-executor1/28201:
 #0:  ((task_exit_notifier).rwsem){.+.+..}, at: [<ffffffff811a5138>] __blocking_notifier_call_chain kernel/notifier.c:316 [inline]
 #0:  ((task_exit_notifier).rwsem){.+.+..}, at: [<ffffffff811a5138>] blocking_notifier_call_chain+0x68/0xa0 kernel/notifier.c:328
1 lock held by syz-executor1/28204:
 #0:  ((task_exit_notifier).rwsem){.+.+..}, at: [<ffffffff811a5138>] __blocking_notifier_call_chain kernel/notifier.c:316 [inline]
 #0:  ((task_exit_notifier).rwsem){.+.+..}, at: [<ffffffff811a5138>] blocking_notifier_call_chain+0x68/0xa0 kernel/notifier.c:328
1 lock held by syz-executor6/28164:
 #0:  ((task_exit_notifier).rwsem){.+.+..}, at: [<ffffffff811a5138>] __blocking_notifier_call_chain kernel/notifier.c:316 [inline]
 #0:  ((task_exit_notifier).rwsem){.+.+..}, at: [<ffffffff811a5138>] blocking_notifier_call_chain+0x68/0xa0 kernel/notifier.c:328
1 lock held by syz-executor6/28166:
 #0:  ((task_exit_notifier).rwsem){.+.+..}, at: [<ffffffff811a5138>] __blocking_notifier_call_chain kernel/notifier.c:316 [inline]
 #0:  ((task_exit_notifier).rwsem){.+.+..}, at: [<ffffffff811a5138>] blocking_notifier_call_chain+0x68/0xa0 kernel/notifier.c:328
1 lock held by syz-executor6/28186:
 #0:  ((task_exit_notifier).rwsem){.+.+..}, at: [<ffffffff811a5138>] __blocking_notifier_call_chain kernel/notifier.c:316 [inline]
 #0:  ((task_exit_notifier).rwsem){.+.+..}, at: [<ffffffff811a5138>] blocking_notifier_call_chain+0x68/0xa0 kernel/notifier.c:328
1 lock held by syz-executor6/28208:
 #0:  ((task_exit_notifier).rwsem){.+.+..}, at: [<ffffffff811a5138>] __blocking_notifier_call_chain kernel/notifier.c:316 [inline]
 #0:  ((task_exit_notifier).rwsem){.+.+..}, at: [<ffffffff811a5138>] blocking_notifier_call_chain+0x68/0xa0 kernel/notifier.c:328
1 lock held by syz-executor2/28165:
 #0:  ((task_exit_notifier).rwsem){.+.+..}, at: [<ffffffff811a5138>] __blocking_notifier_call_chain kernel/notifier.c:316 [inline]
 #0:  ((task_exit_notifier).rwsem){.+.+..}, at: [<ffffffff811a5138>] blocking_notifier_call_chain+0x68/0xa0 kernel/notifier.c:328
1 lock held by syz-executor2/28181:
 #0:  ((task_exit_notifier).rwsem){.+.+..}, at: [<ffffffff811a5138>] __blocking_notifier_call_chain kernel/notifier.c:316 [inline]
 #0:  ((task_exit_notifier).rwsem){.+.+..}, at: [<ffffffff811a5138>] blocking_notifier_call_chain+0x68/0xa0 kernel/notifier.c:328
1 lock held by syz-executor2/28193:
 #0:  ((task_exit_notifier).rwsem){.+.+..}, at: [<ffffffff811a5138>] __blocking_notifier_call_chain kernel/notifier.c:316 [inline]
 #0:  ((task_exit_notifier).rwsem){.+.+..}, at: [<ffffffff811a5138>] blocking_notifier_call_chain+0x68/0xa0 kernel/notifier.c:328
1 lock held by syz-executor2/28215:
 #0:  ((task_exit_notifier).rwsem){.+.+..}, at: [<ffffffff811a5138>] __blocking_notifier_call_chain kernel/notifier.c:316 [inline]
 #0:  ((task_exit_notifier).rwsem){.+.+..}, at: [<ffffffff811a5138>] blocking_notifier_call_chain+0x68/0xa0 kernel/notifier.c:328
1 lock held by syz-executor2/28217:
 #0:  ((task_exit_notifier).rwsem){.+.+..}, at: [<ffffffff811a5138>] __blocking_notifier_call_chain kernel/notifier.c:316 [inline]
 #0:  ((task_exit_notifier).rwsem){.+.+..}, at: [<ffffffff811a5138>] blocking_notifier_call_chain+0x68/0xa0 kernel/notifier.c:328
1 lock held by syz-executor3/28167:
 #0:  (&bdev->bd_mutex){+.+.+.}, at: [<ffffffff816368ba>] blkdev_put+0x2a/0x560 fs/block_dev.c:1621
2 locks held by syz-executor3/28168:
 #0:  (&bdev->bd_mutex){+.+.+.}, at: [<ffffffff81635c3c>] __blkdev_get+0x10c/0xd60 fs/block_dev.c:1268
 #1:  (loop_index_mutex){+.+.+.}, at: [<ffffffff825cbb6b>] lo_open+0x1b/0xa0 drivers/block/loop.c:1564
1 lock held by syz-executor3/28198:
 #0:  ((task_exit_notifier).rwsem){.+.+..}, at: [<ffffffff811a5138>] __blocking_notifier_call_chain kernel/notifier.c:316 [inline]
 #0:  ((task_exit_notifier).rwsem){.+.+..}, at: [<ffffffff811a5138>] blocking_notifier_call_chain+0x68/0xa0 kernel/notifier.c:328
1 lock held by syz-executor3/28210:
 #0:  (&bdev->bd_mutex){+.+.+.}, at: [<ffffffff81635c3c>] __blkdev_get+0x10c/0xd60 fs/block_dev.c:1268
1 lock held by syz-executor3/28211:
 #0:  ((task_exit_notifier).rwsem){.+.+..}, at: [<ffffffff811a5138>] __blocking_notifier_call_chain kernel/notifier.c:316 [inline]
 #0:  ((task_exit_notifier).rwsem){.+.+..}, at: [<ffffffff811a5138>] blocking_notifier_call_chain+0x68/0xa0 kernel/notifier.c:328
1 lock held by syz-executor4/28169:
 #0:  ((task_exit_notifier).rwsem){.+.+..}, at: [<ffffffff811a5138>] __blocking_notifier_call_chain kernel/notifier.c:316 [inline]
 #0:  ((task_exit_notifier).rwsem){.+.+..}, at: [<ffffffff811a5138>] blocking_notifier_call_chain+0x68/0xa0 kernel/notifier.c:328
1 lock held by syz-executor4/28171:
 #0:  ((task_exit_notifier).rwsem){.+.+..}, at: [<ffffffff811a5138>] __blocking_notifier_call_chain kernel/notifier.c:316 [inline]
 #0:  ((task_exit_notifier).rwsem){.+.+..}, at: [<ffffffff811a5138>] blocking_notifier_call_chain+0x68/0xa0 kernel/notifier.c:328
1 lock held by syz-executor5/28173:
 #0:  ((task_exit_notifier).rwsem){.+.+..}, at: [<ffffffff811a5138>] __blocking_notifier_call_chain kernel/notifier.c:316 [inline]
 #0:  ((task_exit_notifier).rwsem){.+.+..}, at: [<ffffffff811a5138>] blocking_notifier_call_chain+0x68/0xa0 kernel/notifier.c:328
2 locks held by syz-executor5/28177:
 #0:  (&lo->lo_ctl_mutex/1){+.+.+.}, at: [<ffffffff825d0b7c>] lo_ioctl+0x8c/0x1690 drivers/block/loop.c:1353
 #1:  (&bdev->bd_mutex){+.+.+.}, at: [<ffffffff81e5bd0e>] blkdev_reread_part+0x1e/0x40 block/ioctl.c:189
1 lock held by syz-executor5/28191:
 #0:  (&bdev->bd_mutex){+.+.+.}, at: [<ffffffff81635c3c>] __blkdev_get+0x10c/0xd60 fs/block_dev.c:1268
1 lock held by syz-executor5/28212:
 #0:  ((task_exit_notifier).rwsem){.+.+..}, at: [<ffffffff811a5138>] __blocking_notifier_call_chain kernel/notifier.c:316 [inline]
 #0:  ((task_exit_notifier).rwsem){.+.+..}, at: [<ffffffff811a5138>] blocking_notifier_call_chain+0x68/0xa0 kernel/notifier.c:328
1 lock held by syz-executor5/28213:
 #0:  ((task_exit_notifier).rwsem){.+.+..}, at: [<ffffffff811a5138>] __blocking_notifier_call_chain kernel/notifier.c:316 [inline]
 #0:  ((task_exit_notifier).rwsem){.+.+..}, at: [<ffffffff811a5138>] blocking_notifier_call_chain+0x68/0xa0 kernel/notifier.c:328
1 lock held by loop6/28176:
 #0:  ((task_exit_notifier).rwsem){.+.+..}, at: [<ffffffff811a5138>] __blocking_notifier_call_chain kernel/notifier.c:316 [inline]
 #0:  ((task_exit_notifier).rwsem){.+.+..}, at: [<ffffffff811a5138>] blocking_notifier_call_chain+0x68/0xa0 kernel/notifier.c:328
1 lock held by syz-executor7/28178:
 #0:  ((task_exit_notifier).rwsem){.+.+..}, at: [<ffffffff811a5138>] __blocking_notifier_call_chain kernel/notifier.c:316 [inline]
 #0:  ((task_exit_notifier).rwsem){.+.+..}, at: [<ffffffff811a5138>] blocking_notifier_call_chain+0x68/0xa0 kernel/notifier.c:328
1 lock held by syz-executor7/28183:
 #0:  ((task_exit_notifier).rwsem){.+.+..}, at: [<ffffffff811a5138>] __blocking_notifier_call_chain kernel/notifier.c:316 [inline]
 #0:  ((task_exit_notifier).rwsem){.+.+..}, at: [<ffffffff811a5138>] blocking_notifier_call_chain+0x68/0xa0 kernel/notifier.c:328
1 lock held by syz-executor7/28199:
 #0:  ((task_exit_notifier).rwsem){.+.+..}, at: [<ffffffff811a5138>] __blocking_notifier_call_chain kernel/notifier.c:316 [inline]
 #0:  ((task_exit_notifier).rwsem){.+.+..}, at: [<ffffffff811a5138>] blocking_notifier_call_chain+0x68/0xa0 kernel/notifier.c:328
3 locks held by blkid/28180:
 #0:  (&bdev->bd_mutex){+.+.+.}, at: [<ffffffff816353ab>] __blkdev_put+0xbb/0x840 fs/block_dev.c:1579
 #1:  (loop_index_mutex){+.+.+.}, at: [<ffffffff825d316f>] lo_release+0x1f/0x1a0 drivers/block/loop.c:1606
 #2:  (&lo->lo_ctl_mutex#2){+.+.+.}, at: [<ffffffff825d31d5>] __lo_release drivers/block/loop.c:1584 [inline]
 #2:  (&lo->lo_ctl_mutex#2){+.+.+.}, at: [<ffffffff825d31d5>] lo_release+0x85/0x1a0 drivers/block/loop.c:1607
2 locks held by blkid/28185:
 #0:  (&bdev->bd_mutex){+.+.+.}, at: [<ffffffff81635c3c>] __blkdev_get+0x10c/0xd60 fs/block_dev.c:1268
 #1:  (loop_index_mutex){+.+.+.}, at: [<ffffffff825cbb6b>] lo_open+0x1b/0xa0 drivers/block/loop.c:1564
2 locks held by blkid/28188:
 #0:  (&bdev->bd_mutex){+.+.+.}, at: [<ffffffff81635c3c>] __blkdev_get+0x10c/0xd60 fs/block_dev.c:1268
 #1:  (loop_index_mutex){+.+.+.}, at: [<ffffffff825cbb6b>] lo_open+0x1b/0xa0 drivers/block/loop.c:1564
1 lock held by syz-executor0/28189:
 #0:  ((task_exit_notifier).rwsem){.+.+..}, at: [<ffffffff811a5138>] __blocking_notifier_call_chain kernel/notifier.c:316 [inline]
 #0:  ((task_exit_notifier).rwsem){.+.+..}, at: [<ffffffff811a5138>] blocking_notifier_call_chain+0x68/0xa0 kernel/notifier.c:328
1 lock held by syz-executor0/28196:
 #0:  ((task_exit_notifier).rwsem){.+.+..}, at: [<ffffffff811a5138>] __blocking_notifier_call_chain kernel/notifier.c:316 [inline]
 #0:  ((task_exit_notifier).rwsem){.+.+..}, at: [<ffffffff811a5138>] blocking_notifier_call_chain+0x68/0xa0 kernel/notifier.c:328
1 lock held by syz-executor0/28200:
 #0:  ((task_exit_notifier).rwsem){.+.+..}, at: [<ffffffff811a5138>] __blocking_notifier_call_chain kernel/notifier.c:316 [inline]
 #0:  ((task_exit_notifier).rwsem){.+.+..}, at: [<ffffffff811a5138>] blocking_notifier_call_chain+0x68/0xa0 kernel/notifier.c:328
1 lock held by blkid/28192:
 #0:  (&bdev->bd_mutex){+.+.+.}, at: [<ffffffff81635c3c>] __blkdev_get+0x10c/0xd60 fs/block_dev.c:1268
1 lock held by modprobe/28194:
 #0:  ((task_exit_notifier).rwsem){.+.+..}, at: [<ffffffff811a5138>] __blocking_notifier_call_chain kernel/notifier.c:316 [inline]
 #0:  ((task_exit_notifier).rwsem){.+.+..}, at: [<ffffffff811a5138>] blocking_notifier_call_chain+0x68/0xa0 kernel/notifier.c:328
1 lock held by modprobe/28197:
 #0:  ((task_exit_notifier).rwsem){.+.+..}, at: [<ffffffff811a5138>] __blocking_notifier_call_chain kernel/notifier.c:316 [inline]
 #0:  ((task_exit_notifier).rwsem){.+.+..}, at: [<ffffffff811a5138>] blocking_notifier_call_chain+0x68/0xa0 kernel/notifier.c:328
1 lock held by modprobe/28202:
 #0:  ((task_exit_notifier).rwsem){.+.+..}, at: [<ffffffff811a5138>] __blocking_notifier_call_chain kernel/notifier.c:316 [inline]
 #0:  ((task_exit_notifier).rwsem){.+.+..}, at: [<ffffffff811a5138>] blocking_notifier_call_chain+0x68/0xa0 kernel/notifier.c:328
1 lock held by modprobe/28203:
 #0:  ((task_exit_notifier).rwsem){.+.+..}, at: [<ffffffff811a5138>] __blocking_notifier_call_chain kernel/notifier.c:316 [inline]
 #0:  ((task_exit_notifier).rwsem){.+.+..}, at: [<ffffffff811a5138>] blocking_notifier_call_chain+0x68/0xa0 kernel/notifier.c:328
1 lock held by modprobe/28205:
 #0:  ((task_exit_notifier).rwsem){.+.+..}, at: [<ffffffff811a5138>] __blocking_notifier_call_chain kernel/notifier.c:316 [inline]
 #0:  ((task_exit_notifier).rwsem){.+.+..}, at: [<ffffffff811a5138>] blocking_notifier_call_chain+0x68/0xa0 kernel/notifier.c:328
1 lock held by modprobe/28206:
 #0:  ((task_exit_notifier).rwsem){.+.+..}, at: [<ffffffff811a5138>] __blocking_notifier_call_chain kernel/notifier.c:316 [inline]
 #0:  ((task_exit_notifier).rwsem){.+.+..}, at: [<ffffffff811a5138>] blocking_notifier_call_chain+0x68/0xa0 kernel/notifier.c:328
2 locks held by kworker/u4:10/28207:
 #0:  ("events_unbound"){.+.+.+}, at: [<ffffffff8118f36e>] work_static include/linux/workqueue.h:186 [inline]
 #0:  ("events_unbound"){.+.+.+}, at: [<ffffffff8118f36e>] set_work_data kernel/workqueue.c:617 [inline]
 #0:  ("events_unbound"){.+.+.+}, at: [<ffffffff8118f36e>] set_work_pool_and_clear_pending kernel/workqueue.c:644 [inline]
 #0:  ("events_unbound"){.+.+.+}, at: [<ffffffff8118f36e>] process_one_work+0x6ee/0x1500 kernel/workqueue.c:2085
 #1:  ((&sub_info->work)){+.+.+.}, at: [<ffffffff8118f3a8>] process_one_work+0x728/0x1500 kernel/workqueue.c:2089
1 lock held by modprobe/28209:
 #0:  ((task_exit_notifier).rwsem){.+.+..}, at: [<ffffffff811a5138>] __blocking_notifier_call_chain kernel/notifier.c:316 [inline]
 #0:  ((task_exit_notifier).rwsem){.+.+..}, at: [<ffffffff811a5138>] blocking_notifier_call_chain+0x68/0xa0 kernel/notifier.c:328
1 lock held by modprobe/28216:
 #0:  ((task_exit_notifier).rwsem){.+.+..}, at: [<ffffffff811a5138>] __blocking_notifier_call_chain kernel/notifier.c:316 [inline]
 #0:  ((task_exit_notifier).rwsem){.+.+..}, at: [<ffffffff811a5138>] blocking_notifier_call_chain+0x68/0xa0 kernel/notifier.c:328
1 lock held by modprobe/28218:
 #0:  ((task_exit_notifier).rwsem){.+.+..}, at: [<ffffffff811a5138>] __blocking_notifier_call_chain kernel/notifier.c:316 [inline]
 #0:  ((task_exit_notifier).rwsem){.+.+..}, at: [<ffffffff811a5138>] blocking_notifier_call_chain+0x68/0xa0 kernel/notifier.c:328
2 locks held by kworker/u4:12/28219:
 #0:  ("events_unbound"){.+.+.+}, at: [<ffffffff8118f36e>] work_static include/linux/workqueue.h:186 [inline]
 #0:  ("events_unbound"){.+.+.+}, at: [<ffffffff8118f36e>] set_work_data kernel/workqueue.c:617 [inline]
 #0:  ("events_unbound"){.+.+.+}, at: [<ffffffff8118f36e>] set_work_pool_and_clear_pending kernel/workqueue.c:644 [inline]
 #0:  ("events_unbound"){.+.+.+}, at: [<ffffffff8118f36e>] process_one_work+0x6ee/0x1500 kernel/workqueue.c:2085
 #1:  ((&sub_info->work)){+.+.+.}, at: [<ffffffff8118f3a8>] process_one_work+0x728/0x1500 kernel/workqueue.c:2089
1 lock held by modprobe/28220:
 #0:  ((task_exit_notifier).rwsem){.+.+..}, at: [<ffffffff811a5138>] __blocking_notifier_call_chain kernel/notifier.c:316 [inline]
 #0:  ((task_exit_notifier).rwsem){.+.+..}, at: [<ffffffff811a5138>] blocking_notifier_call_chain+0x68/0xa0 kernel/notifier.c:328
1 lock held by getty/28221:
 #0:  ((task_exit_notifier).rwsem){.+.+..}, at: [<ffffffff811a5138>] __blocking_notifier_call_chain kernel/notifier.c:316 [inline]
 #0:  ((task_exit_notifier).rwsem){.+.+..}, at: [<ffffffff811a5138>] blocking_notifier_call_chain+0x68/0xa0 kernel/notifier.c:328
1 lock held by getty/28222:
 #0:  ((task_exit_notifier).rwsem){.+.+..}, at: [<ffffffff811a5138>] __blocking_notifier_call_chain kernel/notifier.c:316 [inline]
 #0:  ((task_exit_notifier).rwsem){.+.+..}, at: [<ffffffff811a5138>] blocking_notifier_call_chain+0x68/0xa0 kernel/notifier.c:328
1 lock held by getty/28223:
 #0:  ((task_exit_notifier).rwsem){.+.+..}, at: [<ffffffff811a5138>] __blocking_notifier_call_chain kernel/notifier.c:316 [inline]
 #0:  ((task_exit_notifier).rwsem){.+.+..}, at: [<ffffffff811a5138>] blocking_notifier_call_chain+0x68/0xa0 kernel/notifier.c:328
1 lock held by getty/28224:
 #0:  ((task_exit_notifier).rwsem){.+.+..}, at: [<ffffffff811a5138>] __blocking_notifier_call_chain kernel/notifier.c:316 [inline]
 #0:  ((task_exit_notifier).rwsem){.+.+..}, at: [<ffffffff811a5138>] blocking_notifier_call_chain+0x68/0xa0 kernel/notifier.c:328
1 lock held by getty/28225:
 #0:  ((task_exit_notifier).rwsem){.+.+..}, at: [<ffffffff811a5138>] __blocking_notifier_call_chain kernel/notifier.c:316 [inline]
 #0:  ((task_exit_notifier).rwsem){.+.+..}, at: [<ffffffff811a5138>] blocking_notifier_call_chain+0x68/0xa0 kernel/notifier.c:328
1 lock held by getty/28226:
 #0:  ((task_exit_notifier).rwsem){.+.+..}, at: [<ffffffff811a5138>] __blocking_notifier_call_chain kernel/notifier.c:316 [inline]
 #0:  ((task_exit_notifier).rwsem){.+.+..}, at: [<ffffffff811a5138>] blocking_notifier_call_chain+0x68/0xa0 kernel/notifier.c:328

=============================================

NMI backtrace for cpu 0
CPU: 0 PID: 519 Comm: khungtaskd Not tainted 4.9.123-g520d10d3 #29
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
 ffff8801d857fd08 ffffffff81eb9689 0000000000000000 0000000000000000
 0000000000000000 0000000000000001 ffffffff810b9fa0 ffff8801d857fd40
 ffffffff81ec49c7 0000000000000000 0000000000000000 0000000000000003
Call Trace:
 [<ffffffff81eb9689>] __dump_stack lib/dump_stack.c:15 [inline]
 [<ffffffff81eb9689>] dump_stack+0xc1/0x128 lib/dump_stack.c:51
 [<ffffffff81ec49c7>] nmi_cpu_backtrace.cold.2+0x48/0x87 lib/nmi_backtrace.c:99
 [<ffffffff81ec495a>] nmi_trigger_cpumask_backtrace+0x12a/0x14f lib/nmi_backtrace.c:60
 [<ffffffff810ba0a4>] arch_trigger_cpumask_backtrace+0x14/0x20 arch/x86/kernel/apic/hw_nmi.c:37
 [<ffffffff81369034>] trigger_all_cpu_backtrace include/linux/nmi.h:58 [inline]
 [<ffffffff81369034>] check_hung_task kernel/hung_task.c:125 [inline]
 [<ffffffff81369034>] check_hung_uninterruptible_tasks kernel/hung_task.c:182 [inline]
 [<ffffffff81369034>] watchdog+0x6b4/0xa20 kernel/hung_task.c:239
 [<ffffffff8119f3cd>] kthread+0x26d/0x300 kernel/kthread.c:211
 [<ffffffff83a01f5c>] ret_from_fork+0x5c/0x70 arch/x86/entry/entry_64.S:373
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1 skipped: idling at pc 0xffffffff83a009c6