INFO: task syz.1.699:10642 blocked for more than 143 seconds.
      Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.1.699       state:D stack:25128 pid:10642 tgid:10641 ppid:9892   task_flags:0x400140 flags:0x00004004
Call Trace:
 <TASK>
 __schedule+0x1798/0x4cc0
 schedule+0x165/0x360
 schedule_preempt_disabled+0x13/0x30
 rwsem_down_read_slowpath+0x5fd/0x8f0
 down_read+0x98/0x2e0
 super_lock+0x2a9/0x3b0
 __iterate_supers+0x126/0x290
 ksys_sync+0x94/0x150
 __ia32_sys_sync+0xe/0x20
 do_syscall_64+0xfa/0x3b0
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f8829b8ec29
RSP: 002b:00007f882a95b038 EFLAGS: 00000246 ORIG_RAX: 00000000000000a2
RAX: ffffffffffffffda RBX: 00007f8829dd5fa0 RCX: 00007f8829b8ec29
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000
RBP: 00007f8829dd5fa0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f8829dd6038 R14: 00007f8829dd5fa0 R15: 00007fffc3544b48
 </TASK>
INFO: task syz.1.699:10645 blocked for more than 143 seconds.
      Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.1.699       state:D stack:28936 pid:10645 tgid:10641 ppid:9892   task_flags:0x400040 flags:0x00004004
Call Trace:
 <TASK>
 __schedule+0x1798/0x4cc0
 schedule+0x165/0x360
 schedule_preempt_disabled+0x13/0x30
 rwsem_down_read_slowpath+0x5fd/0x8f0
 down_read+0x98/0x2e0
 super_lock+0x2a9/0x3b0
 __iterate_supers+0x126/0x290
 ksys_sync+0x94/0x150
 __ia32_sys_sync+0xe/0x20
 do_syscall_64+0xfa/0x3b0
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f8829b8ec29
RSP: 002b:00007f882a93a038 EFLAGS: 00000246 ORIG_RAX: 00000000000000a2
RAX: ffffffffffffffda RBX: 00007f8829dd6090 RCX: 00007f8829b8ec29
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000
RBP: 00007f8829dd6090 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f8829dd6128 R14: 00007f8829dd6090 R15: 00007fffc3544b48
 </TASK>

Showing all locks held in the system:
1 lock held by khungtaskd/34:
 #0: ffffffff8e13a0e0 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180
2 locks held by getty/5680:
 #0: ffff88802299b0a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70
 #1: ffffc900029062f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x43e/0x1400
3 locks held by syz-executor/6968:
4 locks held by syz-executor/7801:
1 lock held by syz.1.699/10642:
 #0: ffff88803dd180e0 (&type->s_umount_key#74){++++}-{4:4}, at: super_lock+0x2a9/0x3b0
1 lock held by syz.1.699/10645:
 #0: ffff88803dd180e0 (&type->s_umount_key#74){++++}-{4:4}, at: super_lock+0x2a9/0x3b0
1 lock held by syz.8.948/11588:
 #0: ffff88803dd180e0 (&type->s_umount_key#74){++++}-{4:4}, at: super_lock+0x2a9/0x3b0
1 lock held by syz.6.954/11630:
 #0: ffff88803dd180e0 (&type->s_umount_key#74){++++}-{4:4}, at: super_lock+0x2a9/0x3b0
2 locks held by dhcpcd/11648:
 #0: ffff88811bf17408 (&sb->s_type->i_mutex_key#11){+.+.}-{4:4}, at: sock_close+0x9b/0x240
 #1: ffffffff8e13fb78 (rcu_state.exp_mutex){+.+.}-{4:4}, at: synchronize_rcu_expedited+0x3b9/0x730
1 lock held by syz-executor/12063:
1 lock held by syz.0.1030/12129:
 #0: ffff88803d9800e0 (&type->s_umount_key#74){++++}-{4:4}, at: super_lock+0x2a9/0x3b0
1 lock held by syz.2.1063/12605:
 #0: ffff88803dd180e0 (&type->s_umount_key#74){++++}-{4:4}, at: super_lock+0x2a9/0x3b0
1 lock held by syz.1.1073/12691:
 #0: ffff88803dd180e0 (&type->s_umount_key#74){++++}-{4:4}, at: super_lock+0x2a9/0x3b0
9 locks held by syz-executor/12819:
 #0: ffff888027f04428 (sb_writers#7){.+.+}-{0:0}, at: vfs_write+0x211/0xb30
 #1: ffff88803e8b9488 (&of->mutex){+.+.}-{4:4}, at: kernfs_fop_write_iter+0x1de/0x540
 #2: ffff888109264f08 (kn->active#48){.+.+}-{0:0}, at: kernfs_fop_write_iter+0x231/0x540
 #3: ffffffff8edb0408 (nsim_bus_dev_list_lock){+.+.}-{4:4}, at: del_device_store+0xd1/0x360
 #4: ffff88803a1620e8 (&dev->mutex){....}-{4:4}, at: device_release_driver_internal+0xb6/0x800
 #5: ffff88803a161250 (&devlink->lock_key#23){+.+.}-{4:4}, at: nsim_drv_remove+0x50/0x160
 #6: ffffffff8f53a1c8 (rtnl_mutex){+.+.}-{4:4}, at: nsim_destroy+0xe5/0x670
 #7: ffff88811ac6cd30 (&dev_instance_lock_key#20){+.+.}-{4:4}, at: unregister_netdevice_many_notify+0xdf5/0x1ff0
 #8: ffffffff8e13fb78 (rcu_state.exp_mutex){+.+.}-{4:4}, at: synchronize_rcu_expedited+0x3b9/0x730
2 locks held by rm/12850:

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

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+0x189/0x250
 nmi_cpu_backtrace+0x39e/0x3d0
 nmi_trigger_cpumask_backtrace+0x17a/0x300
 watchdog+0xf93/0xfe0
 kthread+0x711/0x8a0
 ret_from_fork+0x439/0x7d0
 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: 6968 Comm: syz-executor 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
RIP: 0010:mark_lock+0x3c/0x190
Code: 00 03 00 83 f9 01 bb 09 00 00 00 83 db 00 83 fa 08 0f 45 da bd 01 00 00 00 89 d9 d3 e5 25 ff 1f 00 00 48 0f a3 05 04 06 0b 12 <73> 10 48 69 c0 c8 00 00 00 48 8d 88 10 93 49 93 eb 48 83 3d 6b 95
RSP: 0018:ffffc9000416f758 EFLAGS: 00000003
RAX: 0000000000000a10 RBX: 0000000000000006 RCX: 0000000000000006
RDX: 0000000000000006 RSI: ffff888109292800 RDI: ffff888109291cc0
RBP: 0000000000000040 R08: 0000000000000000 R09: ffffffff840a310c
R10: dffffc0000000000 R11: ffffed100554e939 R12: 0000000000000004
R13: 0000000000000004 R14: ffff888109292800 R15: 0000000000000000
FS:  0000555567770500(0000) GS:ffff8881a3c13000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000561388d89680 CR3: 0000000115856000 CR4: 00000000000006f0
Call Trace:
 <TASK>
 __lock_acquire+0x9e2/0xd20
 lock_acquire+0x120/0x360
 down_write+0x96/0x1f0
 f2fs_write_checkpoint+0x51c/0x1df0
 kill_f2fs_super+0x2c3/0x6c0
 deactivate_locked_super+0xbc/0x130
 cleanup_mnt+0x425/0x4c0
 task_work_run+0x1d4/0x260
 exit_to_user_mode_loop+0xec/0x110
 do_syscall_64+0x2bd/0x3b0
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f476298ff57
Code: a8 ff ff ff f7 d8 64 89 01 48 83 c8 ff c3 0f 1f 44 00 00 31 f6 e9 09 00 00 00 66 0f 1f 84 00 00 00 00 00 b8 a6 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 01 c3 48 c7 c2 a8 ff ff ff f7 d8 64 89 02 b8
RSP: 002b:00007ffd1326bce8 EFLAGS: 00000246 ORIG_RAX: 00000000000000a6
RAX: 0000000000000000 RBX: 00007f4762a11c2d RCX: 00007f476298ff57
RDX: 0000000000000000 RSI: 0000000000000009 RDI: 00007ffd1326bda0
RBP: 00007ffd1326bda0 R08: 0000000000000000 R09: 0000000000000000
R10: 00000000ffffffff R11: 0000000000000246 R12: 00007ffd1326ce30
R13: 00007f4762a11c2d R14: 000000000002406f R15: 00007ffd1326ce70
 </TASK>
