INFO: task kworker/u9:8:1104 blocked for more than 143 seconds.
      Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:kworker/u9:8    state:D stack:22104 pid:1104  tgid:1104  ppid:2      task_flags:0x4208060 flags:0x00080000
Workqueue: writeback wb_workfn (flush-7:4)
Call Trace:
 <TASK>
 __schedule+0x14bc/0x5000
 schedule+0x165/0x360
 schedule_preempt_disabled+0x13/0x30
 __mutex_lock+0x7e6/0x1350
 jfs_commit_inode+0x1ca/0x530
 jfs_write_inode+0x145/0x220
 __writeback_single_inode+0x7e1/0x1240
 writeback_sb_inodes+0x93a/0x1870
 __writeback_inodes_wb+0x111/0x240
 wb_writeback+0x43f/0xaa0
 wb_workfn+0x8ee/0xed0
 process_scheduled_works+0xad1/0x1770
 worker_thread+0x8a0/0xda0
 kthread+0x711/0x8a0
 ret_from_fork+0x599/0xb30
 ret_from_fork_asm+0x1a/0x30
 </TASK>
INFO: task syz.0.594:10717 blocked for more than 143 seconds.
      Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.0.594       state:D stack:24408 pid:10717 tgid:10715 ppid:9291   task_flags:0x400140 flags:0x00080002
Call Trace:
 <TASK>
 __schedule+0x14bc/0x5000
 schedule+0x165/0x360
 wb_wait_for_completion+0x360/0x680
 sync_inodes_sb+0x1c9/0xb40
 __iterate_supers+0x13d/0x290
 ksys_sync+0x94/0x150
 __ia32_sys_sync+0xe/0x20
 do_syscall_64+0xfa/0xf80
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fc85218f7c9
RSP: 002b:00007fc852ffa038 EFLAGS: 00000246 ORIG_RAX: 00000000000000a2
RAX: ffffffffffffffda RBX: 00007fc8523e6090 RCX: 00007fc85218f7c9
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000
RBP: 00007fc8523e6090 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007fc8523e6128 R14: 00007fc8523e6090 R15: 00007ffd4f625288
 </TASK>
INFO: task syz.6.603:10747 blocked for more than 143 seconds.
      Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.6.603       state:D stack:22680 pid:10747 tgid:10746 ppid:7022   task_flags:0x400140 flags:0x00080002
Call Trace:
 <TASK>
 __schedule+0x14bc/0x5000
 schedule+0x165/0x360
 schedule_preempt_disabled+0x13/0x30
 rwsem_down_write_slowpath+0x872/0xfe0
 down_write+0x1ab/0x1f0
 sync_inodes_sb+0x1ad/0xb40
 __iterate_supers+0x13d/0x290
 ksys_sync+0x94/0x150
 __ia32_sys_sync+0xe/0x20
 do_syscall_64+0xfa/0xf80
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f8c29d8f7c9
RSP: 002b:00007f8c2ac56038 EFLAGS: 00000246 ORIG_RAX: 00000000000000a2
RAX: ffffffffffffffda RBX: 00007f8c29fe5fa0 RCX: 00007f8c29d8f7c9
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000
RBP: 00007f8c29fe5fa0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f8c29fe6038 R14: 00007f8c29fe5fa0 R15: 00007ffc8f74a6a8
 </TASK>

Showing all locks held in the system:
1 lock held by khungtaskd/35:
 #0: ffffffff8df419e0 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180
4 locks held by kworker/u9:8/1104:
 #0: ffff8881616d5948 ((wq_completion)writeback){+.+.}-{0:0}, at: process_scheduled_works+0x9b4/0x1770
 #1: ffffc9000830fb80 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_scheduled_works+0x9ef/0x1770
 #2: ffff8881767300e0 (&type->s_umount_key#76){++++}-{4:4}, at: super_trylock_shared+0x20/0xf0
 #3: ffff8880214b6fa8 (&jfs_ip->commit_mutex){+.+.}-{4:4}, at: jfs_commit_inode+0x1ca/0x530
2 locks held by getty/5653:
 #0: ffff8881764dd0a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70
 #1: ffffc900034402f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x449/0x1460
3 locks held by kworker/1:3/5868:
 #0: ffff888100075948 ((wq_completion)events){+.+.}-{0:0}, at: process_scheduled_works+0x9b4/0x1770
 #1: ffffc90005717b80 ((work_completion)(&data->fib_event_work)){+.+.}-{0:0}, at: process_scheduled_works+0x9ef/0x1770
 #2: ffff8881607cd240 (&data->fib_lock){+.+.}-{4:4}, at: nsim_fib_event_work+0x1f7/0x3b0
4 locks held by syz.4.576/10585:
2 locks held by syz.0.594/10717:
 #0: ffff8881767300e0 (&type->s_umount_key#76){++++}-{4:4}, at: super_lock+0x2a9/0x3b0
 #1: ffff888109b2a820 (&bdi->wb_switch_rwsem){+.+.}-{4:4}, at: sync_inodes_sb+0x1ad/0xb40
2 locks held by syz.6.603/10747:
 #0: ffff8881767300e0 (&type->s_umount_key#76){++++}-{4:4}, at: super_lock+0x2a9/0x3b0
 #1: ffff888109b2a820 (&bdi->wb_switch_rwsem){+.+.}-{4:4}, at: sync_inodes_sb+0x1ad/0xb40
2 locks held by syz.1.604/10818:
 #0: ffff8881767300e0 (&type->s_umount_key#76){++++}-{4:4}, at: super_lock+0x2a9/0x3b0
 #1: ffff888109b2a820 (&bdi->wb_switch_rwsem){+.+.}-{4:4}, at: sync_inodes_sb+0x1ad/0xb40
2 locks held by syz.5.605/10920:
 #0: ffff8881767300e0 (&type->s_umount_key#76){++++}-{4:4}, at: super_lock+0x2a9/0x3b0
 #1: ffff888109b2a820 (&bdi->wb_switch_rwsem){+.+.}-{4:4}, at: sync_inodes_sb+0x1ad/0xb40
2 locks held by syz.7.607/11056:
 #0: ffff8881767300e0 (&type->s_umount_key#76){++++}-{4:4}, at: super_lock+0x2a9/0x3b0
 #1: ffff888109b2a820 (&bdi->wb_switch_rwsem){+.+.}-{4:4}, at: sync_inodes_sb+0x1ad/0xb40
2 locks held by syz.8.609/11152:
 #0: ffff8881767300e0 (&type->s_umount_key#76){++++}-{4:4}, at: super_lock+0x2a9/0x3b0
 #1: ffff888109b2a820 (&bdi->wb_switch_rwsem){+.+.}-{4:4}, at: sync_inodes_sb+0x1ad/0xb40
2 locks held by syz.2.620/11393:
 #0: ffff8881767300e0 (&type->s_umount_key#76){++++}-{4:4}, at: super_lock+0x2a9/0x3b0
 #1: ffff888109b2a820 (&bdi->wb_switch_rwsem){+.+.}-{4:4}, at: sync_inodes_sb+0x1ad/0xb40
2 locks held by syz.3.628/11581:
 #0: ffff8881767300e0 (&type->s_umount_key#76){++++}-{4:4}, at: super_lock+0x2a9/0x3b0
 #1: ffff888109b2a820 (&bdi->wb_switch_rwsem){+.+.}-{4:4}, at: sync_inodes_sb+0x1ad/0xb40
2 locks held by syz.4.632/11590:
 #0: ffff8881767300e0 (&type->s_umount_key#76){++++}-{4:4}, at: super_lock+0x2a9/0x3b0
 #1: ffff888109b2a820 (&bdi->wb_switch_rwsem){+.+.}-{4:4}, at: sync_inodes_sb+0x1ad/0xb40
2 locks held by syz.0.636/11650:
 #0: ffff8881767300e0 (&type->s_umount_key#76){++++}-{4:4}, at: super_lock+0x2a9/0x3b0
 #1: ffff888109b2a820 (&bdi->wb_switch_rwsem){+.+.}-{4:4}, at: sync_inodes_sb+0x1ad/0xb40
2 locks held by syz.1.642/11710:
 #0: ffff8881767300e0 (&type->s_umount_key#76){++++}-{4:4}, at: super_lock+0x2a9/0x3b0
 #1: ffff888109b2a820 (&bdi->wb_switch_rwsem){+.+.}-{4:4}, at: sync_inodes_sb+0x1ad/0xb40
2 locks held by syz.6.645/11719:
 #0: ffff8881767300e0 (&type->s_umount_key#76){++++}-{4:4}, at: super_lock+0x2a9/0x3b0
 #1: ffff888109b2a820 (&bdi->wb_switch_rwsem){+.+.}-{4:4}, at: sync_inodes_sb+0x1ad/0xb40
2 locks held by syz.5.650/11758:
 #0: ffff8881767300e0 (&type->s_umount_key#76){++++}-{4:4}, at: super_lock+0x2a9/0x3b0
 #1: ffff888109b2a820 (&bdi->wb_switch_rwsem){+.+.}-{4:4}, at: sync_inodes_sb+0x1ad/0xb40
2 locks held by syz.5.650/11759:
 #0: ffff8881767300e0 (&type->s_umount_key#76){++++}-{4:4}, at: super_lock+0x2a9/0x3b0
 #1: ffff888109b2a820 (&bdi->wb_switch_rwsem){+.+.}-{4:4}, at: sync_inodes_sb+0x1ad/0xb40
2 locks held by syz.9.678/11985:
 #0: ffff8881767300e0 (&type->s_umount_key#76){++++}-{4:4}, at: super_lock+0x2a9/0x3b0
 #1: ffff888109b2a820 (&bdi->wb_switch_rwsem){+.+.}-{4:4}, at: sync_inodes_sb+0x1ad/0xb40
2 locks held by syz.8.685/12009:
 #0: ffff8881767300e0 (&type->s_umount_key#76){++++}-{4:4}, at: super_lock+0x2a9/0x3b0
 #1: ffff888109b2a820 (&bdi->wb_switch_rwsem){+.+.}-{4:4}, at: sync_inodes_sb+0x1ad/0xb40
2 locks held by syz.7.686/12011:
 #0: ffff8881767300e0 (&type->s_umount_key#76){++++}-{4:4}, at: super_lock+0x2a9/0x3b0
 #1: ffff888109b2a820 (&bdi->wb_switch_rwsem){+.+.}-{4:4}, at: sync_inodes_sb+0x1ad/0xb40
2 locks held by syz.2.689/12046:
 #0: ffff8881767300e0 (&type->s_umount_key#76){++++}-{4:4}, at: super_lock+0x2a9/0x3b0
 #1: ffff888109b2a820 (&bdi->wb_switch_rwsem){+.+.}-{4:4}, at: sync_inodes_sb+0x1ad/0xb40
2 locks held by syz.4.696/12127:
 #0: ffff8881767300e0 (&type->s_umount_key#76){++++}-{4:4}, at: super_lock+0x2a9/0x3b0
 #1: ffff888109b2a820 (&bdi->wb_switch_rwsem){+.+.}-{4:4}, at: sync_inodes_sb+0x1ad/0xb40
2 locks held by syz.3.702/12175:
 #0: ffff8881767300e0 (&type->s_umount_key#76){++++}-{4:4}, at: super_lock+0x2a9/0x3b0
 #1: ffff888109b2a820 (&bdi->wb_switch_rwsem){+.+.}-{4:4}, at: sync_inodes_sb+0x1ad/0xb40
2 locks held by syz.0.704/12204:
 #0: ffff8881767300e0 (&type->s_umount_key#76){++++}-{4:4}, at: super_lock+0x2a9/0x3b0
 #1: ffff888109b2a820 (&bdi->wb_switch_rwsem){+.+.}-{4:4}, at: sync_inodes_sb+0x1ad/0xb40
2 locks held by syz.1.714/12283:
 #0: ffff8881767300e0 (&type->s_umount_key#76){++++}-{4:4}, at: super_lock+0x2a9/0x3b0
 #1: ffff888109b2a820 (&bdi->wb_switch_rwsem){+.+.}-{4:4}, at: sync_inodes_sb+0x1ad/0xb40
2 locks held by syz.6.718/12289:
 #0: ffff8881767300e0 (&type->s_umount_key#76){++++}-{4:4}, at: super_lock+0x2a9/0x3b0
 #1: ffff888109b2a820 (&bdi->wb_switch_rwsem){+.+.}-{4:4}, at: sync_inodes_sb+0x1ad/0xb40
2 locks held by syz.5.719/12320:
 #0: ffff8881767300e0 (&type->s_umount_key#76){++++}-{4:4}, at: super_lock+0x2a9/0x3b0
 #1: ffff888109b2a820 (&bdi->wb_switch_rwsem){+.+.}-{4:4}, at: sync_inodes_sb+0x1ad/0xb40

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

NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 35 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
 sys_info+0x135/0x170
 watchdog+0xf95/0xfe0
 kthread+0x711/0x8a0
 ret_from_fork+0x599/0xb30
 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: 10585 Comm: syz.4.576 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:__sanitizer_cov_trace_pc+0x3c/0x70
Code: 8b 15 68 af bc 10 81 e2 00 01 ff 00 74 11 81 fa 00 01 00 00 75 35 83 b9 6c 16 00 00 00 74 2c 8b 91 48 16 00 00 83 fa 02 75 21 <48> 8b 91 50 16 00 00 48 8b 32 48 8d 7e 01 8b 89 4c 16 00 00 48 39
RSP: 0018:ffffc900070f7680 EFLAGS: 00000246
RAX: ffffffff834a167f RBX: 0000000000000004 RCX: ffff888170370000
RDX: 0000000000000002 RSI: 0000000000000000 RDI: 00000000000000ff
RBP: 0000000000000000 R08: 0000000200000000 R09: 0000000000000000
R10: 0030000000000000 R11: 000007ff00000020 R12: dffffc0000000000
R13: ffff8881b9b76000 R14: 0000000000000000 R15: 1ffff1103736ec02
FS:  00007fb07b6bb6c0(0000) GS:ffff8882a9e3a000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f79f2e87e20 CR3: 0000000113602000 CR4: 00000000000006f0
Call Trace:
 <TASK>
 dtSplitRoot+0x77f/0x16c0
 dtInsert+0xef8/0x5f40
 jfs_mkdir+0x6ec/0xa70
 vfs_mkdir+0x512/0x5b0
 do_mkdirat+0x276/0x4b0
 __x64_sys_mkdirat+0x87/0xa0
 do_syscall_64+0xfa/0xf80
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fb07a78df17
Code: 73 01 c3 48 c7 c1 a8 ff ff ff f7 d8 64 89 01 48 83 c8 ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 00 b8 02 01 00 00 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 a8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007fb07b6bae68 EFLAGS: 00000246 ORIG_RAX: 0000000000000102
RAX: ffffffffffffffda RBX: 00007fb07b6baef0 RCX: 00007fb07a78df17
RDX: 00000000000001ff RSI: 0000200000000500 RDI: 00000000ffffff9c
RBP: 00002000000002c0 R08: 0000200000000040 R09: 0000000000000000
R10: 00002000000002c0 R11: 0000000000000246 R12: 0000200000000500
R13: 00007fb07b6baeb0 R14: 0000000000000000 R15: 0000000000000000
 </TASK>
