INFO: task syz-executor:5611 blocked for more than 143 seconds.
      Not tainted syzkaller #0
      Blocked by coredump.
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz-executor    state:D stack:22080 pid:5611  tgid:5611  ppid:1      task_flags:0x40014c flags:0x00080001
Call Trace:
 <TASK>
 __schedule+0x1821/0x5740
 schedule+0x164/0x360
 schedule_preempt_disabled+0x13/0x30
 rwsem_down_write_slowpath+0x883/0x1080
 down_write+0x1bc/0x200
 deactivate_super+0xa9/0xe0
 cleanup_mnt+0x437/0x4d0
 task_work_run+0x1d9/0x270
 do_exit+0x70f/0x22c0
 do_group_exit+0x21b/0x2d0
 __x64_sys_exit_group+0x3f/0x40
 x64_sys_call+0x221a/0x2240
 do_syscall_64+0x15f/0x560
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f7dded9ce59
RSP: 002b:00007fffe6b481a8 EFLAGS: 00000246 ORIG_RAX: 00000000000000e7
RAX: ffffffffffffffda RBX: 00007f7ddee3224e RCX: 00007f7dded9ce59
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000001
RBP: 0000000000000001 R08: 0000000000000000 R09: 00007f7ddee321ca
R10: 0000000000000000 R11: 0000000000000246 R12: 00007fffe6b49460
R13: 00007f7ddee321ca R14: 0000555575bc14e8 R15: 00007fffe6b4a530
 </TASK>
INFO: task syz.4.369:8022 blocked for more than 143 seconds.
      Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.4.369       state:D stack:27144 pid:8022  tgid:8021  ppid:7688   task_flags:0x400040 flags:0x00080002
Call Trace:
 <TASK>
 __schedule+0x1821/0x5740
 schedule+0x164/0x360
 schedule_preempt_disabled+0x13/0x30
 rwsem_down_read_slowpath+0x6d9/0x940
 down_read+0x99/0x2e0
 super_lock+0x2d6/0x3d0
 __iterate_supers+0x126/0x250
 __se_sys_quotactl+0x3a7/0x9e0
 do_syscall_64+0x15f/0x560
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f669a99ce59
RSP: 002b:00007f669b7a0028 EFLAGS: 00000246 ORIG_RAX: 00000000000000b3
RAX: ffffffffffffffda RBX: 00007f669ac15fa0 RCX: 00007f669a99ce59
RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffffffff80000100
RBP: 00007f669aa32d6f R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f669ac16038 R14: 00007f669ac15fa0 R15: 00007ffdcc5322f8
 </TASK>
INFO: task syz.4.369:8024 blocked for more than 143 seconds.
      Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.4.369       state:D stack:28024 pid:8024  tgid:8021  ppid:7688   task_flags:0x400040 flags:0x00080002
Call Trace:
 <TASK>
 __schedule+0x1821/0x5740
 schedule+0x164/0x360
 schedule_preempt_disabled+0x13/0x30
 rwsem_down_read_slowpath+0x6d9/0x940
 down_read+0x99/0x2e0
 super_lock+0x2d6/0x3d0
 __iterate_supers+0x126/0x250
 __se_sys_quotactl+0x3a7/0x9e0
 do_syscall_64+0x15f/0x560
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f669a99ce59
RSP: 002b:00007f669b77f028 EFLAGS: 00000246 ORIG_RAX: 00000000000000b3
RAX: ffffffffffffffda RBX: 00007f669ac16090 RCX: 00007f669a99ce59
RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffffffff80000102
RBP: 00007f669aa32d6f R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f669ac16128 R14: 00007f669ac16090 R15: 00007ffdcc5322f8
 </TASK>
INFO: task syz.4.369:8027 blocked for more than 143 seconds.
      Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.4.369       state:D stack:28024 pid:8027  tgid:8021  ppid:7688   task_flags:0x400040 flags:0x00080002
Call Trace:
 <TASK>
 __schedule+0x1821/0x5740
 schedule+0x164/0x360
 schedule_preempt_disabled+0x13/0x30
 rwsem_down_read_slowpath+0x6d9/0x940
 down_read+0x99/0x2e0
 super_lock+0x2d6/0x3d0
 __iterate_supers+0x126/0x250
 __se_sys_quotactl+0x3a7/0x9e0
 do_syscall_64+0x15f/0x560
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f669a99ce59
RSP: 002b:00007f6698bf6028 EFLAGS: 00000246 ORIG_RAX: 00000000000000b3
RAX: ffffffffffffffda RBX: 00007f669ac16180 RCX: 00007f669a99ce59
RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffffffff80000100
RBP: 00007f669aa32d6f R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f669ac16218 R14: 00007f669ac16180 R15: 00007ffdcc5322f8
 </TASK>

Showing all locks held in the system:
1 lock held by pool_workqueue_/3:
 #0: ffffffff8e962fe8 (rcu_state.exp_mutex){+.+.}-{4:4}, at: synchronize_rcu_expedited+0x38d/0x770
1 lock held by khungtaskd/34:
 #0: ffffffff8e95cce0 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180
3 locks held by kworker/u9:7/1112:
 #0: ffff8881000ac140 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_scheduled_works+0xa35/0x1860
 #1: ffffc90007917c40 ((linkwatch_work).work){+.+.}-{0:0}, at: process_scheduled_works+0xa70/0x1860
 #2: ffffffff8fdd1b00 (rtnl_mutex){+.+.}-{4:4}, at: linkwatch_event+0xe/0x60
5 locks held by kworker/u10:5/3370:
1 lock held by dhcpcd/5356:
 #0: ffffffff8fdd1b00 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_newlink+0x883/0x1bb0
2 locks held by getty/5441:
 #0: ffff88810b8110a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70
 #1: ffffc900034762e8 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x45c/0x13a0
1 lock held by syz-executor/5611:
 #0: ffff8881b97d60d8 (&type->s_umount_key#60){++++}-{4:4}, at: deactivate_super+0xa9/0xe0
1 lock held by syz.4.369/8022:
 #0: ffff8881b97d60d8 (&type->s_umount_key#60){++++}-{4:4}, at: super_lock+0x2d6/0x3d0
1 lock held by syz.4.369/8024:
 #0: ffff8881b97d60d8 (&type->s_umount_key#60){++++}-{4:4}, at: super_lock+0x2d6/0x3d0
1 lock held by syz.4.369/8027:
 #0: ffff8881b97d60d8 (&type->s_umount_key#60){++++}-{4:4}, at: super_lock+0x2d6/0x3d0
5 locks held by kworker/u8:4/8894:
 #0: ffff8881012b5940 ((wq_completion)netns){+.+.}-{0:0}, at: process_scheduled_works+0xa35/0x1860
 #1: ffffc90007107c40 (net_cleanup_work){+.+.}-{0:0}, at: process_scheduled_works+0xa70/0x1860
 #2: ffffffff8fdc2e28 (pernet_ops_rwsem){++++}-{4:4}, at: cleanup_net+0xf4/0x800
 #3: ffff8881118f1590 (&wg->device_update_lock){+.+.}-{4:4}, at: wg_destruct+0x116/0x310
 #4: ffffffff8e962eb8 (rcu_state.barrier_mutex){+.+.}-{4:4}, at: rcu_barrier+0x4c/0x580
1 lock held by syz.3.661/10204:
 #0: ffff8881b97d60d8 (&type->s_umount_key#60){++++}-{4:4}, at: super_lock+0x2d6/0x3d0
1 lock held by syz.0.711/10721:
 #0: ffff8881b97d60d8 (&type->s_umount_key#60){++++}-{4:4}, at: super_lock+0x2d6/0x3d0
1 lock held by syz.0.711/10722:
 #0: ffff8881b97d60d8 (&type->s_umount_key#60){++++}-{4:4}, at: super_lock+0x2d6/0x3d0
8 locks held by syz-executor/11708:
 #0: ffff888112718410 (sb_writers#7){.+.+}-{0:0}, at: vfs_write+0x227/0xb90
 #1: ffff8881166a5480 (&of->mutex){+.+.}-{4:4}, at: kernfs_fop_write_iter+0x1de/0x540
 #2: ffff88816b1ad008 (kn->active#48){.+.+}-{0:0}, at: kernfs_fop_write_iter+0x231/0x540
 #3: ffffffff8f650800 (nsim_bus_dev_list_lock){+.+.}-{4:4}, at: del_device_store+0xd7/0x370
 #4: ffff88816ae4d128 (&dev->mutex){....}-{4:4}, at: device_release_driver_internal+0xb6/0x870
 #5: ffff88816ae49258 (&devlink->lock_key#8){+.+.}-{4:4}, at: nsim_drv_remove+0x50/0x170
 #6: ffffffff8fdd1b00 (rtnl_mutex){+.+.}-{4:4}, at: nsim_destroy+0x16b/0x7f0
 #7: ffffffff8e962fe8 (rcu_state.exp_mutex){+.+.}-{4:4}, at: synchronize_rcu_expedited+0x38d/0x770
3 locks held by syz.6.870/11798:
 #0: ffff888029748ea0 (&hdev->req_lock){+.+.}-{4:4}, at: hci_unregister_dev+0x212/0x5a0
 #1: ffff8880297480b8 (&hdev->lock){+.+.}-{4:4}, at: hci_dev_close_sync+0x640/0x10e0
 #2: ffffffff8ff55260 (hci_cb_list_lock){+.+.}-{4:4}, at: hci_conn_hash_flush+0xa1/0x260
4 locks held by syz.4.867/11802:
 #0: ffff8881a8dfcea0 (&hdev->req_lock){+.+.}-{4:4}, at: hci_unregister_dev+0x212/0x5a0
 #1: ffff8881a8dfc0b8 (&hdev->lock){+.+.}-{4:4}, at: hci_dev_close_sync+0x640/0x10e0
 #2: ffffffff8ff55260 (hci_cb_list_lock){+.+.}-{4:4}, at: hci_conn_hash_flush+0xa1/0x260
 #3: ffff888021320af8 (&conn->lock#2){+.+.}-{4:4}, at: l2cap_conn_del+0x92/0x570

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

NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 34 Comm: khungtaskd Not tainted syzkaller #0 PREEMPT(full) 
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.2-debian-1.16.2-1 04/01/2014
Call Trace:
 <TASK>
 dump_stack_lvl+0xe8/0x150
 nmi_cpu_backtrace+0x274/0x2d0
 nmi_trigger_cpumask_backtrace+0x17a/0x300
 sys_info+0x135/0x170
 watchdog+0xfd3/0x1030
 kthread+0x389/0x470
 ret_from_fork+0x514/0xb70
 ret_from_fork_asm+0x1a/0x30
 </TASK>
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 3370 Comm: kworker/u10:5 Not tainted syzkaller #0 PREEMPT(full) 
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.2-debian-1.16.2-1 04/01/2014
Workqueue: writeback wb_workfn (flush-7:1)
RIP: 0010:do_raw_spin_lock+0x138/0x2f0
Code: df be 04 00 00 00 49 89 d6 e8 84 b4 8e 00 48 8d 7c 24 40 be 04 00 00 00 e8 75 b4 8e 00 8b 44 24 40 b9 01 00 00 00 f0 0f b1 0b <0f> 85 20 01 00 00 43 c6 44 34 04 f8 65 8b 1d 79 48 97 11 43 0f b6
RSP: 0018:ffffc90009e76900 EFLAGS: 00000246
RAX: 0000000000000000 RBX: ffff88816b3d0c18 RCX: 0000000000000001
RDX: 0000000000000001 RSI: 0000000000000004 RDI: ffffc90009e76940
RBP: ffffc90009e769b0 R08: 0000000000000003 R09: 0000000000000004
R10: dffffc0000000000 R11: fffff520013ced28 R12: 1ffff920013ced24
R13: ffff88816b3d0c20 R14: dffffc0000000000 R15: 1ffff1102d67a184
FS:  0000000000000000(0000) GS:ffff8882a9287000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000560ceab01e48 CR3: 0000000020b6c000 CR4: 00000000000006f0
Call Trace:
 <TASK>
 f2fs_write_checkpoint+0xb3b/0x26a0
 f2fs_issue_checkpoint+0x456/0x790
 f2fs_balance_fs_bg+0x576/0x990
 f2fs_write_node_pages+0x158/0x700
 do_writepages+0x32e/0x550
 __writeback_single_inode+0x133/0x10e0
 writeback_sb_inodes+0x979/0x19d0
 __writeback_inodes_wb+0x111/0x240
 wb_writeback+0x459/0xb00
 wb_workfn+0xb12/0xf10
 process_scheduled_works+0xb5d/0x1860
 worker_thread+0xa53/0xfc0
 kthread+0x389/0x470
 ret_from_fork+0x514/0xb70
 ret_from_fork_asm+0x1a/0x30
 </TASK>
