INFO: task kworker/u10:5:95 blocked for more than 143 seconds.
      Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:kworker/u10:5   state:D stack:24800 pid:95    tgid:95    ppid:2      task_flags:0x4208060 flags:0x00080000
Workqueue: writeback wb_workfn (flush-7:2)
Call Trace:
 <TASK>
 __schedule+0x15dd/0x52d0
 schedule+0x164/0x360
 schedule_preempt_disabled+0x13/0x30
 __mutex_lock+0x7fe/0x1300
 jfs_commit_inode+0x1ca/0x530
 jfs_write_inode+0x145/0x220
 __writeback_single_inode+0x75a/0x11a0
 writeback_sb_inodes+0x992/0x1a20
 __writeback_inodes_wb+0x111/0x240
 wb_writeback+0x46a/0xb70
 wb_workfn+0xb4c/0xf50
 process_scheduled_works+0xb02/0x1830
 worker_thread+0xa50/0xfc0
 kthread+0x388/0x470
 ret_from_fork+0x51e/0xb90
 ret_from_fork_asm+0x1a/0x30
 </TASK>

Showing all locks held in the system:
3 locks held by kworker/0:1/10:
 #0: ffff88810006b148 ((wq_completion)events){+.+.}-{0:0}, at: process_scheduled_works+0x9ea/0x1830
 #1: ffffc900000f7c40 ((work_completion)(&data->fib_event_work)){+.+.}-{0:0}, at: process_scheduled_works+0xa25/0x1830
 #2: ffff88811f3df240 (&data->fib_lock){+.+.}-{4:4}, at: nsim_fib_event_work+0x202/0x3d0
1 lock held by khungtaskd/34:
 #0: ffffffff8e75e3e0 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180
4 locks held by kworker/u10:5/95:
 #0: ffff8881622fe948 ((wq_completion)writeback){+.+.}-{0:0}, at: process_scheduled_works+0x9ea/0x1830
 #1: ffffc900028cfc40 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_scheduled_works+0xa25/0x1830
 #2: ffff8881bd4820e0 (&type->s_umount_key#74){++++}-{4:4}, at: super_trylock_shared+0x20/0xf0
 #3: ffff8881bcb0b8b8 (&jfs_ip->commit_mutex){+.+.}-{4:4}, at: jfs_commit_inode+0x1ca/0x530
2 locks held by getty/5634:
 #0: ffff88816d4400a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70
 #1: ffffc9000356e2f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x45c/0x13c0
3 locks held by kworker/1:5/5876:
 #0: ffff88810006b148 ((wq_completion)events){+.+.}-{0:0}, at: process_scheduled_works+0x9ea/0x1830
 #1: ffffc9000637fc40 (free_ipc_work){+.+.}-{0:0}, at: process_scheduled_works+0xa25/0x1830
 #2: ffffffff8e764678 (rcu_state.exp_mutex){+.+.}-{4:4}, at: synchronize_rcu_expedited+0x2d0/0x770
4 locks held by syz.2.10/5908:
2 locks held by syz-executor/6130:
 #0: ffff88816fde40e0 (&type->s_umount_key#74){++++}-{4:4}, at: deactivate_super+0xa9/0xe0
 #1: ffffffff8ebec628 (jfs_log_mutex){+.+.}-{4:4}, at: lmLogClose+0xb4/0x520
2 locks held by syz-executor/6222:
 #0: ffff8881aaac80e0 (&type->s_umount_key#74){++++}-{4:4}, at: deactivate_super+0xa9/0xe0
 #1: ffffffff8ebec628 (jfs_log_mutex){+.+.}-{4:4}, at: lmLogClose+0xb4/0x520
2 locks held by syz-executor/7438:
 #0: ffff88810e9d00e0 (&type->s_umount_key#74){++++}-{4:4}, at: deactivate_super+0xa9/0xe0
 #1: ffffffff8ebec628 (jfs_log_mutex){+.+.}-{4:4}, at: lmLogClose+0xb4/0x520
2 locks held by syz-executor/7644:
 #0: ffff88817751a0e0 (&type->s_umount_key#74){++++}-{4:4}, at: deactivate_super+0xa9/0xe0
 #1: ffffffff8ebec628 (jfs_log_mutex){+.+.}-{4:4}, at: lmLogClose+0xb4/0x520
1 lock held by syz.4.397/7937:
 #0: ffff88816fde40e0 (&type->s_umount_key#74){++++}-{4:4}, at: super_lock+0x2d6/0x3d0
2 locks held by syz-executor/8007:
 #0: ffff8881713ce0e0 (&type->s_umount_key#74){++++}-{4:4}, at: deactivate_super+0xa9/0xe0
 #1: ffffffff8ebec628 (jfs_log_mutex){+.+.}-{4:4}, at: lmLogClose+0xb4/0x520
2 locks held by syz-executor/8160:
 #0: ffff88802404c0e0 (&type->s_umount_key#74){++++}-{4:4}, at: deactivate_super+0xa9/0xe0
 #1: ffffffff8ebec628 (jfs_log_mutex){+.+.}-{4:4}, at: lmLogClose+0xb4/0x520
1 lock held by syz.5.639/9210:
 #0: ffff8881aaac80e0 (&type->s_umount_key#74){++++}-{4:4}, at: super_lock+0x289/0x3d0
1 lock held by syz.0.651/9343:
 #0: ffffffff8e764678 (rcu_state.exp_mutex){+.+.}-{4:4}, at: synchronize_rcu_expedited+0x38d/0x770
1 lock held by syz.2.653/9349:
1 lock held by dhcpcd/9350:
 #0: ffff888112138260 (sk_lock-AF_PACKET){+.+.}-{0:0}, at: packet_do_bind+0x33/0xe10

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

NMI backtrace for cpu 1
CPU: 1 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+0xfd9/0x1030
 kthread+0x388/0x470
 ret_from_fork+0x51e/0xb90
 ret_from_fork_asm+0x1a/0x30
 </TASK>
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 9343 Comm: syz.0.651 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:lock_acquire+0x10d/0x2e0
Code: b4 24 88 00 00 00 41 56 e8 80 02 00 00 48 83 c4 28 48 c7 c7 f8 55 16 8e e8 50 75 0c 0a b8 ff ff ff ff 65 0f c1 05 33 8d 7a 11 <83> f8 01 0f 85 b0 00 00 00 9c 58 a9 00 02 00 00 0f 85 c3 00 00 00
RSP: 0018:ffffc90003a074e0 EFLAGS: 00000057
RAX: 0000000000000001 RBX: 0000000000000246 RCX: 0000000000000046
RDX: 000000005a44979c RSI: ffffffff8e1655f8 RDI: ffffffff8c27b380
RBP: 0000000000000000 R08: ffffffff81767de5 R09: ffffffff8e75e3e0
R10: ffffc90003a07678 R11: ffffffff81b0bfa0 R12: 0000000000000002
R13: ffffffff8e75e3e0 R14: 0000000000000000 R15: 0000000000000000
FS:  00007f8e2f9176c0(0000) GS:ffff88818de63000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fffac0ded08 CR3: 000000016a624000 CR4: 00000000000006f0
Call Trace:
 <TASK>
 unwind_next_frame+0xc2/0x23c0
 arch_stack_walk+0x11b/0x150
 stack_trace_save+0xa9/0x100
 save_stack+0x122/0x230
 __reset_page_owner+0x71/0x1f0
 __free_frozen_pages+0xc2b/0xdb0
 vfree+0x25a/0x400
 kcov_close+0x28/0x50
 __fput+0x44f/0xa70
 task_work_run+0x1d9/0x270
 do_exit+0x70f/0x23c0
 do_group_exit+0x21b/0x2d0
 get_signal+0x1284/0x1330
 arch_do_signal_or_restart+0xbc/0x830
 exit_to_user_mode_loop+0x86/0x480
 do_syscall_64+0x32d/0xf80
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f8e2e95cfce
Code: Unable to access opcode bytes at 0x7f8e2e95cfa4.
RSP: 002b:00007f8e2f916da8 EFLAGS: 00000246 ORIG_RAX: 0000000000000003
RAX: 0000000000000000 RBX: 00007f8e2f9176c0 RCX: 00007f8e2e95cfce
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000003
RBP: 0000000000000010 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000003
R13: 00007f8e2f916ee0 R14: 00007f8e2f916ea0 R15: 00007f8e24600000
 </TASK>
