INFO: task kworker/u9:9:2964 blocked for more than 143 seconds.
      Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:kworker/u9:9    state:D stack:23464 pid:2964  tgid:2964  ppid:2      task_flags:0x4208060 flags:0x00080000
Workqueue: writeback wb_workfn (flush-7:0)
Call Trace:
 <TASK>
 __schedule+0x14ef/0x4fb0
 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+0x7e1/0x1230
 writeback_sb_inodes+0x92c/0x1820
 __writeback_inodes_wb+0x111/0x240
 wb_writeback+0x459/0xad0
 wb_workfn+0x8fd/0xef0
 process_scheduled_works+0xaec/0x17a0
 worker_thread+0x89f/0xd90
 kthread+0x726/0x8b0
 ret_from_fork+0x51b/0xa40
 ret_from_fork_asm+0x1a/0x30
 </TASK>
INFO: task syz.0.1:5921 blocked for more than 143 seconds.
      Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.0.1         state:D stack:20504 pid:5921  tgid:5918  ppid:5837   task_flags:0x400740 flags:0x00080002
Call Trace:
 <TASK>
 __schedule+0x14ef/0x4fb0
 schedule+0x164/0x360
 io_schedule+0x7f/0xd0
 lock_metapage+0x1ff/0x400
 __get_metapage+0x49a/0xde0
 xtSplitPage+0x281/0x2150
 xtSplitUp+0x33c/0x1fc0
 xtInsert+0x452/0xf20
 extAlloc+0xad9/0x1020
 jfs_get_block+0x358/0xad0
 __block_write_begin_int+0x6c6/0x1910
 block_write_begin+0x8d/0x120
 jfs_write_begin+0x35/0x80
 generic_perform_write+0x2e2/0x8f0
 generic_file_write_iter+0x14a/0x680
 __kernel_write_iter+0x41e/0x880
 dump_user_range+0x8ba/0xc70
 elf_core_dump+0x34c2/0x3ad0
 coredump_write+0x11de/0x1980
 vfs_coredump+0x369e/0x4270
 get_signal+0x1107/0x1330
 arch_do_signal_or_restart+0xbc/0x830
 exit_to_user_mode_loop+0x86/0x480
 do_syscall_64+0x2b7/0xf80
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: cd63:0x7f42f2c15fa0
RSP: 0003:00007f42f2c15fa8 EFLAGS: 00000202
RAX: 0000000000000000 RBX: 00007f42f285098e RCX: 00007f42f39250d0
RDX: 0000000000000044 RSI: 0000000000000000 RDI: 0000000000000000
RBP: 0000000000000000 R08: 0000000000000010 R09: 00007f42f2c15fa0
R10: 00000000f3925070 R11: ffffffff000015f0 R12: 00007f42f2b7c020
R13: 00007f42f2c15fd0 R14: 0000000000000044 R15: 0000000004b02669
 </TASK>
INFO: task poweroff:5968 blocked for more than 143 seconds.
      Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:poweroff        state:D stack:23480 pid:5968  tgid:5968  ppid:5265   task_flags:0x400000 flags:0x00080000
Call Trace:
 <TASK>
 __schedule+0x14ef/0x4fb0
 schedule+0x164/0x360
 wb_wait_for_completion+0x372/0x690
 sync_inodes_sb+0x1de/0xbd0
 __iterate_supers+0x13d/0x290
 __ia32_sys_sync+0xa0/0x120
 do_syscall_64+0xe2/0xf80
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f2bb1c2d7e7
RSP: 002b:00007ffffa632808 EFLAGS: 00000246 ORIG_RAX: 00000000000000a2
RAX: ffffffffffffffda RBX: 0000000000000001 RCX: 00007f2bb1c2d7e7
RDX: 0000000000000078 RSI: 00007f2bb1dbc8ca RDI: 00000000ffffff9c
RBP: 0000000000000000 R08: 0000000000000001 R09: 00007f2bb1dbc8ca
R10: 0000000000000000 R11: 0000000000000246 R12: 00007ffffa632958
R13: 00007ffffa632968 R14: 000055786816b169 R15: 00007f2bb1e0da80
 </TASK>

Showing all locks held in the system:
1 lock held by khungtaskd/35:
 #0: ffffffff8e35a360 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180
4 locks held by kworker/u9:9/2964:
 #0: ffff888103af8948 ((wq_completion)writeback){+.+.}-{0:0}, at: process_scheduled_works+0x9d4/0x17a0
 #1: ffffc90024087bc0 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_scheduled_works+0xa0f/0x17a0
 #2: ffff888111dd60e0 (&type->s_umount_key#62){++++}-{4:4}, at: super_trylock_shared+0x20/0xf0
 #3: ffff8881b8b5efa8 (&jfs_ip->commit_mutex){+.+.}-{4:4}, at: jfs_commit_inode+0x1ca/0x530
3 locks held by kworker/u10:15/3594:
 #0: ffff888100089948 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_scheduled_works+0x9d4/0x17a0
 #1: ffffc90024f77bc0 ((linkwatch_work).work){+.+.}-{0:0}, at: process_scheduled_works+0xa0f/0x17a0
 #2: ffffffff8f7aa488 (rtnl_mutex){+.+.}-{4:4}, at: linkwatch_event+0xe/0x60
1 lock held by dhcpcd/5577:
 #0: ffffffff8f7aa488 (rtnl_mutex){+.+.}-{4:4}, at: devinet_ioctl+0x32b/0x1b30
2 locks held by getty/5661:
 #0: ffff88816d1210a0 (&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
4 locks held by kworker/u8:4/5868:
 #0: ffff888100ef7948 ((wq_completion)netns){+.+.}-{0:0}, at: process_scheduled_works+0x9d4/0x17a0
 #1: ffffc900053a7bc0 (net_cleanup_work){+.+.}-{0:0}, at: process_scheduled_works+0xa0f/0x17a0
 #2: ffffffff8f79bb10 (pernet_ops_rwsem){++++}-{4:4}, at: cleanup_net+0xfe/0x7b0
 #3: ffffffff8f7aa488 (rtnl_mutex){+.+.}-{4:4}, at: cangw_pernet_exit_batch+0x20/0x90
4 locks held by syz.0.1/5921:
 #0: ffff888111dd6420 (sb_writers#12){.+.+}-{0:0}, at: vfs_coredump+0x369e/0x4270
 #1: ffff8881b8b5f358 (&sb->s_type->i_mutex_key#24){+.+.}-{4:4}, at: generic_file_write_iter+0x11e/0x680
 #2: ffff8881b8b5ef18 (&jfs_ip->rdwrlock#2){+.+.}-{4:4}, at: jfs_get_block+0x153/0xad0
 #3: ffff8881b8b5efa8 (&jfs_ip->commit_mutex){+.+.}-{4:4}, at: extAlloc+0x130/0x1020
2 locks held by poweroff/5968:
 #0: ffff888111dd60e0 (&type->s_umount_key#62){++++}-{4:4}, at: super_lock+0x2d6/0x3d0
 #1: ffff888109032820 (&bdi->wb_switch_rwsem){+.+.}-{4:4}, at: sync_inodes_sb+0x1c2/0xbd0
5 locks held by kworker/0:6/6054:
 #0: ffff888104e82948 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: process_scheduled_works+0x9d4/0x17a0
 #1: ffffc90007997bc0 ((work_completion)(&hub->events)){+.+.}-{0:0}, at: process_scheduled_works+0xa0f/0x17a0
 #2: ffff88823c4c0998 (&dev->mutex){....}-{4:4}, at: hub_event+0x17f/0x4f30
 #3: ffff88810ad77518 (&port_dev->status_lock){+.+.}-{4:4}, at: hub_event+0x217a/0x4f30
 #4: ffff88810ad2c868 (hcd->address0_mutex){+.+.}-{4:4}, at: hub_event+0x21a2/0x4f30
2 locks held by syz.1.337/7528:
 #0: ffffffff8f7aa488 (rtnl_mutex){+.+.}-{4:4}, at: tun_chr_close+0x3e/0x1c0
 #1: ffffffff8e360c78 (rcu_state.exp_mutex){+.+.}-{4:4}, at: synchronize_rcu_expedited+0x2d0/0x770
5 locks held by syz-executor/8683:
 #0: ffff888110bc4ec0 (&hdev->req_lock){+.+.}-{4:4}, at: hci_unregister_dev+0x212/0x5a0
 #1: ffff888110bc40c0 (&hdev->lock){+.+.}-{4:4}, at: hci_dev_close_sync+0x640/0x10e0
 #2: ffffffff8f936808 (hci_cb_list_lock){+.+.}-{4:4}, at: hci_conn_hash_flush+0xa1/0x260
 #3: ffff888112943338 (&conn->lock#2){+.+.}-{4:4}, at: l2cap_conn_del+0x7b/0x5b0
 #4: ffffffff8e360c78 (rcu_state.exp_mutex){+.+.}-{4:4}, at: synchronize_rcu_expedited+0x38d/0x770
3 locks held by syz.5.609/8710:
 #0: ffff88816c78cec0 (&hdev->req_lock){+.+.}-{4:4}, at: hci_unregister_dev+0x212/0x5a0
 #1: ffff88816c78c0c0 (&hdev->lock){+.+.}-{4:4}, at: hci_dev_close_sync+0x640/0x10e0
 #2: ffffffff8f936808 (hci_cb_list_lock){+.+.}-{4:4}, at: hci_conn_hash_flush+0xa1/0x260

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

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+0xe8/0x150
 nmi_cpu_backtrace+0x274/0x2d0
 nmi_trigger_cpumask_backtrace+0x17a/0x300
 sys_info+0x135/0x170
 watchdog+0xf90/0xfe0
 kthread+0x726/0x8b0
 ret_from_fork+0x51b/0xa40
 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: 0 Comm: swapper/1 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:pv_native_safe_halt+0xf/0x20
Code: b8 5e 02 e9 d3 e5 02 00 cc cc cc 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 f3 0f 1e fa eb 07 0f 00 2d d3 27 10 00 fb f4 <c3> cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc 90 90 90 90 90
RSP: 0018:ffffc90000197e20 EFLAGS: 00000202
RAX: 0000000000474b6b RBX: ffffffff81984a1d RCX: 0000000080000001
RDX: 0000000000000001 RSI: ffffffff8dad1a6e RDI: ffffffff8be74b80
RBP: ffffc90000197f10 R08: ffff88823c6336db R09: 1ffff110478c66db
R10: dffffc0000000000 R11: ffffed10478c66dc R12: ffffffff8fcef870
R13: 1ffff1102c09f000 R14: 0000000000000001 R15: 0000000000000001
FS:  0000000000000000(0000) GS:ffff8882a9923000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007ffc1bddd158 CR3: 000000000e146000 CR4: 00000000000006f0
Call Trace:
 <TASK>
 default_idle+0x9/0x20
 default_idle_call+0x72/0xb0
 do_idle+0x1bd/0x500
 cpu_startup_entry+0x43/0x60
 start_secondary+0x101/0x110
 common_startup_64+0x13e/0x147
 </TASK>
