INFO: task syz.6.2441:19031 blocked for more than 143 seconds.
      Tainted: G             L      syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.6.2441      state:D stack:24648 pid:19031 tgid:19030 ppid:18765  task_flags:0x400140 flags:0x00080002
Call Trace:
 <TASK>
 __schedule+0x17b4/0x5680
 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
 __ia32_sys_sync+0xa0/0x120
 do_syscall_64+0x15f/0xf80
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f8c7cf9cdd9
RSP: 002b:00007f8c7de38028 EFLAGS: 00000246 ORIG_RAX: 00000000000000a2
RAX: ffffffffffffffda RBX: 00007f8c7d215fa0 RCX: 00007f8c7cf9cdd9
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000
RBP: 00007f8c7d215fa0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f8c7d216038 R14: 00007f8c7d215fa0 R15: 00007fff92331c58
 </TASK>
INFO: task syz.5.2475:19292 blocked for more than 143 seconds.
      Tainted: G             L      syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.5.2475      state:D stack:24648 pid:19292 tgid:19291 ppid:18036  task_flags:0x400140 flags:0x00080002
Call Trace:
 <TASK>
 __schedule+0x17b4/0x5680
 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
 __ia32_sys_sync+0xa0/0x120
 do_syscall_64+0x15f/0xf80
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fa19139cdd9
RSP: 002b:00007fa19217e028 EFLAGS: 00000246 ORIG_RAX: 00000000000000a2
RAX: ffffffffffffffda RBX: 00007fa191615fa0 RCX: 00007fa19139cdd9
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000
RBP: 00007fa191615fa0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007fa191616038 R14: 00007fa191615fa0 R15: 00007fffe3f59988
 </TASK>

Showing all locks held in the system:
1 lock held by khungtaskd/35:
 #0: ffffffff8e95cda0 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180
6 locks held by kworker/0:3/1296:
 #0: ffff888104adf940 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: process_scheduled_works+0xa35/0x1860
 #1: ffffc9000860fc40 ((work_completion)(&hub->events)){+.+.}-{0:0}, at: process_scheduled_works+0xa70/0x1860
 #2: ffff88810aa791d8 (&dev->mutex){....}-{4:4}, at: hub_event+0x17f/0x4f30
 #3: ffff88811636f1d8 (&dev->mutex){....}-{4:4}, at: __device_attach+0x88/0x450
 #4: ffff88811636b1a0 (&dev->mutex){....}-{4:4}, at: __device_attach+0x88/0x450
 #5: ffffffff8e7f9b28 (umhelper_sem){++++}-{4:4}, at: usermodehelper_read_trylock+0xfc/0x2c0
2 locks held by getty/5438:
 #0: ffff88816d1650a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70
 #1: ffffc9000346b2e8 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x45c/0x13a0
3 locks held by syz-executor/15080:
5 locks held by kworker/1:13/15338:
 #0: ffff888104adf940 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: process_scheduled_works+0xa35/0x1860
 #1: ffffc90004c0fc40 ((work_completion)(&hub->events)){+.+.}-{0:0}, at: process_scheduled_works+0xa70/0x1860
 #2: ffff88810a8a91d8 (&dev->mutex){....}-{4:4}, at: hub_event+0x17f/0x4f30
 #3: ffff8881bc1071d8 (&dev->mutex){....}-{4:4}, at: __device_attach+0x88/0x450
 #4: ffff8881a9b441a0 (&dev->mutex){....}-{4:4}, at: __device_attach+0x88/0x450
1 lock held by syz.6.2441/19031:
 #0: ffff8881ac3f20d8 (&type->s_umount_key#82){++++}-{4:4}, at: super_lock+0x2d6/0x3d0
1 lock held by syz.5.2475/19292:
 #0: ffff8881ac3f20d8 (&type->s_umount_key#82){++++}-{4:4}, at: super_lock+0x2d6/0x3d0
1 lock held by syz.7.2552/19786:
 #0: ffff8881ac3f20d8 (&type->s_umount_key#82){++++}-{4:4}, at: super_lock+0x2d6/0x3d0
1 lock held by syz.7.2552/19798:
 #0: ffff8881ac3f20d8 (&type->s_umount_key#82){++++}-{4:4}, at: super_lock+0x2d6/0x3d0

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

NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 35 Comm: khungtaskd Tainted: G             L      syzkaller #0 PREEMPT(full) 
Tainted: [L]=SOFTLOCKUP
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+0x388/0x470
 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: 15080 Comm: syz-executor Tainted: G             L      syzkaller #0 PREEMPT(full) 
Tainted: [L]=SOFTLOCKUP
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.2-debian-1.16.2-1 04/01/2014
RIP: 0010:__lock_acquire+0x341/0x2cf0
Code: 8b 54 24 10 83 e2 01 c1 e2 12 44 09 ea c1 e3 14 09 d3 8b 14 24 c1 e2 13 41 c1 e4 15 41 09 d4 41 09 cc 41 09 dc 45 89 64 c7 20 <41> 89 7c c7 24 4c 89 7c 24 20 4d 8d 2c c7 41 81 e4 ff 1f 00 00 4c
RSP: 0018:ffffc900036c75b8 EFLAGS: 00000006
RAX: 000000000000000f RBX: 0000000000040000 RCX: 0000000000000b99
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000
RBP: 0000000000000003 R08: ffffffff84356d90 R09: ffff888198ea8508
R10: dffffc0000000000 R11: ffffed10331d521f R12: 0000000000040b99
R13: 0000000000000000 R14: ffff888111559d80 R15: ffff88811155a910
FS:  000055555f871500(0000) GS:ffff8882a9293000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f63343ea2f8 CR3: 000000011b6ac000 CR4: 00000000000006f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000600
Call Trace:
 <TASK>
 lock_acquire+0x106/0x350
 down_write+0x96/0x200
 f2fs_write_checkpoint+0xa10/0x26a0
 kill_f2fs_super+0x314/0x730
 deactivate_locked_super+0xbc/0x130
 cleanup_mnt+0x437/0x4d0
 task_work_run+0x1d9/0x270
 exit_to_user_mode_loop+0xed/0x480
 do_syscall_64+0x33e/0xf80
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7ff18d39e017
Code: a2 c7 05 dc 06 25 00 00 00 00 00 eb 96 e8 e1 12 00 00 90 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 e8 ff ff ff f7 d8 64 89 02 b8
RSP: 002b:00007ffde197de28 EFLAGS: 00000246 ORIG_RAX: 00000000000000a6
RAX: 0000000000000000 RBX: 00007ff18d432120 RCX: 00007ff18d39e017
RDX: 0000000000000000 RSI: 0000000000000009 RDI: 00007ffde197dee0
RBP: 00007ffde197dee0 R08: 00007ffde197eee0 R09: 00000000ffffffff
R10: 0000000000000000 R11: 0000000000000246 R12: 00007ffde197ef70
R13: 00007ff18d432120 R14: 00000000000a1e20 R15: 00007ffde197efb0
 </TASK>
