INFO: task syz-executor.2:23018 blocked for more than 140 seconds.
      Not tainted 4.9.141+ #1
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
syz-executor.2  D29544 23018  19390 0x00000004
 ffff8801d5db97c0 ffff8801d3dec200 ffff8801adef9600 ffff8801d30e0000
 ffff8801db621018 ffff8801c9b079c8 ffffffff828075c2 0000000000000000
 ffff8801d5dba070 ffffed003abb740d 00ff8801d5db97c0 ffff8801db6218f0
Call Trace:
 [<ffffffff82808aef>] schedule+0x7f/0x1b0 kernel/sched/core.c:3553
 [<ffffffff828094a3>] schedule_preempt_disabled+0x13/0x20 kernel/sched/core.c:3586
 [<ffffffff8280b51d>] __mutex_lock_common kernel/locking/mutex.c:582 [inline]
 [<ffffffff8280b51d>] mutex_lock_nested+0x38d/0x900 kernel/locking/mutex.c:621
 [<ffffffff81de73ac>] lo_ioctl+0x8c/0x1910 drivers/block/loop.c:1372
 [<ffffffff81b0cf54>] __blkdev_driver_ioctl block/ioctl.c:294 [inline]
 [<ffffffff81b0cf54>] blkdev_ioctl+0x7a4/0x1a50 block/ioctl.c:590
 [<ffffffff815ca29e>] block_ioctl+0xde/0x120 fs/block_dev.c:1688
 [<ffffffff81546dec>] vfs_ioctl fs/ioctl.c:43 [inline]
 [<ffffffff81546dec>] file_ioctl fs/ioctl.c:493 [inline]
 [<ffffffff81546dec>] do_vfs_ioctl+0x1ac/0x11a0 fs/ioctl.c:677
 [<ffffffff81547e6f>] SYSC_ioctl fs/ioctl.c:694 [inline]
 [<ffffffff81547e6f>] SyS_ioctl+0x8f/0xc0 fs/ioctl.c:685
 [<ffffffff810056ef>] do_syscall_64+0x19f/0x550 arch/x86/entry/common.c:285
 [<ffffffff82817893>] entry_SYSCALL_64_after_swapgs+0x5d/0xdb

Showing all locks held in the system:
2 locks held by khungtaskd/24:
 #0:  (rcu_read_lock){......}, at: [<ffffffff8131c0cc>] check_hung_uninterruptible_tasks kernel/hung_task.c:168 [inline]
 #0:  (rcu_read_lock){......}, at: [<ffffffff8131c0cc>] watchdog+0x11c/0xa20 kernel/hung_task.c:239
 #1:  (tasklist_lock){.+.+..}, at: [<ffffffff813fe63f>] debug_show_all_locks+0x79/0x218 kernel/locking/lockdep.c:4336
1 lock held by rsyslogd/1897:
 #0:  (&f->f_pos_lock){+.+.+.}, at: [<ffffffff8156cc7c>] __fdget_pos+0xac/0xd0 fs/file.c:781
2 locks held by getty/2024:
 #0:  (&tty->ldisc_sem){++++++}, at: [<ffffffff82815952>] ldsem_down_read+0x32/0x40 drivers/tty/tty_ldsem.c:367
 #1:  (&ldata->atomic_read_lock){+.+...}, at: [<ffffffff81d37362>] n_tty_read+0x202/0x16e0 drivers/tty/n_tty.c:2142
3 locks held by kworker/u4:2/2112:
 #0:  ("%s""netns"){.+.+.+}, at: [<ffffffff81130f0c>] process_one_work+0x73c/0x15f0 kernel/workqueue.c:2085
 #1:  (net_cleanup_work){+.+.+.}, at: [<ffffffff81130f44>] process_one_work+0x774/0x15f0 kernel/workqueue.c:2089
 #2:  (net_mutex){+.+.+.}, at: [<ffffffff822e681f>] cleanup_net+0x13f/0x8b0 net/core/net_namespace.c:439
1 lock held by syz-executor.0/23011:
 #0:  (rcu_preempt_state.barrier_mutex){+.+...}, at: [<ffffffff8124b1fd>] _rcu_barrier+0x5d/0x340 kernel/rcu/tree.c:3637
1 lock held by syz-executor.3/23014:
 #0:  (&lo->lo_ctl_mutex/1){+.+.+.}, at: [<ffffffff81de73ac>] lo_ioctl+0x8c/0x1910 drivers/block/loop.c:1372
1 lock held by syz-executor.2/23018:
 #0:  (&lo->lo_ctl_mutex/1){+.+.+.}, at: [<ffffffff81de73ac>] lo_ioctl+0x8c/0x1910 drivers/block/loop.c:1372
1 lock held by syz-executor.2/23020:
 #0:  (&lo->lo_ctl_mutex/1){+.+.+.}, at: [<ffffffff81de73ac>] lo_ioctl+0x8c/0x1910 drivers/block/loop.c:1372
1 lock held by blkid/23034:
 #0:  (&lo->lo_ctl_mutex/1){+.+.+.}, at: [<ffffffff81de73ac>] lo_ioctl+0x8c/0x1910 drivers/block/loop.c:1372

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

NMI backtrace for cpu 1
CPU: 1 PID: 24 Comm: khungtaskd Not tainted 4.9.141+ #1
 ffff8801d9907d08 ffffffff81b42e79 0000000000000000 0000000000000001
 0000000000000001 0000000000000001 ffffffff810983b0 ffff8801d9907d40
 ffffffff81b4df89 0000000000000001 0000000000000000 0000000000000002
Call Trace:
 [<ffffffff81b42e79>] __dump_stack lib/dump_stack.c:15 [inline]
 [<ffffffff81b42e79>] dump_stack+0xc1/0x128 lib/dump_stack.c:51
 [<ffffffff81b4df89>] nmi_cpu_backtrace.cold.0+0x48/0x87 lib/nmi_backtrace.c:99
 [<ffffffff81b4df1c>] nmi_trigger_cpumask_backtrace+0x12c/0x151 lib/nmi_backtrace.c:60
 [<ffffffff810984b4>] arch_trigger_cpumask_backtrace+0x14/0x20 arch/x86/kernel/apic/hw_nmi.c:37
 [<ffffffff8131c65d>] trigger_all_cpu_backtrace include/linux/nmi.h:58 [inline]
 [<ffffffff8131c65d>] check_hung_task kernel/hung_task.c:125 [inline]
 [<ffffffff8131c65d>] check_hung_uninterruptible_tasks kernel/hung_task.c:182 [inline]
 [<ffffffff8131c65d>] watchdog+0x6ad/0xa20 kernel/hung_task.c:239
 [<ffffffff81142c3d>] kthread+0x26d/0x300 kernel/kthread.c:211
 [<ffffffff82817a5c>] ret_from_fork+0x5c/0x70 arch/x86/entry/entry_64.S:373
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 PID: 16545 Comm: syz-executor.5 Not tainted 4.9.141+ #1
task: ffff8801d50cc740 task.stack: ffff8801cfa58000
RIP: 0010:[<ffffffff81205a66>] 
c [<ffffffff81205a66>] mark_lock+0x16/0x1290 kernel/locking/lockdep.c:3032
RSP: 0018:ffff8801cfa5f748  EFLAGS: 00000046
RAX: dffffc0000000000 RBX: ffff8801d50ccff0 RCX: 000000000000000c
RDX: 000000000000000c RSI: ffff8801d50ccff0 RDI: ffff8801d50cc740
RBP: ffff8801cfa5f750 R08: ffff8801d50cd010 R09: 0000000000000001
R10: ffff8801d50cc740 R11: 0000000000000001 R12: 0000000000000002
R13: 0000000000000000 R14: 0000000000000000 R15: ffff8801d50cd012
FS:  00007f37e289e700(0000) GS:ffff8801db600000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000001354000 CR3: 00000001c6a03000 CR4: 00000000001606b0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Stack:
 ffff8801d50cd012
c ffff8801cfa5f910
c ffffffff81207a04
c ffffffff8155ff6e
c
 ffffffff8156236e
c ffffffff81562816
c ffffffff81563a01
c ffffffff8154feb5
c
 ffffffff81553e22
c ffffffff815552a6
c ffffffff8155549f
c ffffffff8151045f
c
Call Trace:
 [<ffffffff81207a04>] __lock_acquire+0x654/0x4a10 kernel/locking/lockdep.c:3306
 [<ffffffff8120c8d0>] lock_acquire+0x130/0x3e0 kernel/locking/lockdep.c:3756
 [<ffffffff82816dde>] __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:112 [inline]
 [<ffffffff82816dde>] _raw_spin_lock_irqsave+0x4e/0x70 kernel/locking/spinlock.c:159
 [<ffffffff81ba9131>] __debug_object_init+0xc1/0x970 lib/debugobjects.c:318
 [<ffffffff81baa63a>] debug_object_init lib/debugobjects.c:366 [inline]
 [<ffffffff81baa63a>] debug_object_activate+0x25a/0x4e0 lib/debugobjects.c:447
 [<ffffffff8124e135>] debug_rcu_head_queue kernel/rcu/rcu.h:75 [inline]
 [<ffffffff8124e135>] __call_rcu.constprop.61+0x35/0x910 kernel/rcu/tree.c:3138
 [<ffffffff8124ea22>] call_rcu+0x12/0x20 kernel/rcu/tree_plugin.h:655
 [<ffffffff81a06ff6>] inode_free_security security/selinux/hooks.c:357 [inline]
 [<ffffffff81a06ff6>] selinux_inode_free_security+0x1c6/0x2b0 security/selinux/hooks.c:2830
 [<ffffffff819e3c96>] security_inode_free+0x56/0x90 security/security.c:356
 [<ffffffff8155ff6e>] __destroy_inode+0x2e/0x220 fs/inode.c:235
 [<ffffffff8156236e>] destroy_inode+0x4e/0x120 fs/inode.c:262
 [<ffffffff81562816>] evict+0x3d6/0x620 fs/inode.c:570
 [<ffffffff81563a01>] iput_final fs/inode.c:1516 [inline]
 [<ffffffff81563a01>] iput+0x371/0x900 fs/inode.c:1543
 [<ffffffff8154feb5>] dentry_unlink_inode+0x265/0x320 fs/dcache.c:368
 [<ffffffff81553e22>] __dentry_kill+0x322/0x5b0 fs/dcache.c:570
 [<ffffffff815552a6>] dentry_kill fs/dcache.c:611 [inline]
 [<ffffffff815552a6>] dput.part.9+0x5c6/0x7a0 fs/dcache.c:828
 [<ffffffff8155549f>] dput+0x1f/0x30 fs/dcache.c:790
 [<ffffffff8151045f>] __fput+0x42f/0x700 fs/file_table.c:226
 [<ffffffff815107b5>] ____fput+0x15/0x20 fs/file_table.c:244
 [<ffffffff8113dc4c>] task_work_run+0x10c/0x180 kernel/task_work.c:116
 [<ffffffff81003e49>] tracehook_notify_resume include/linux/tracehook.h:191 [inline]
 [<ffffffff81003e49>] exit_to_usermode_loop+0x129/0x150 arch/x86/entry/common.c:162
 [<ffffffff81005932>] prepare_exit_to_usermode arch/x86/entry/common.c:194 [inline]
 [<ffffffff81005932>] syscall_return_slowpath arch/x86/entry/common.c:263 [inline]
 [<ffffffff81005932>] do_syscall_64+0x3e2/0x550 arch/x86/entry/common.c:290
 [<ffffffff82817893>] entry_SYSCALL_64_after_swapgs+0x5d/0xdb
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