INFO: task syz-executor:11921 blocked for more than 143 seconds.
      Not tainted 6.16.0-rc7-syzkaller-dirty #0
      Blocked by coredump.
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz-executor    state:D stack:21496 pid:11921 tgid:11921 ppid:1      task_flags:0x40014c flags:0x00004002
Call Trace:
 <TASK>
 __schedule+0x16fd/0x4cf0
 schedule+0x165/0x360
 wb_wait_for_completion+0x15f/0x260
 sync_inodes_sb+0x1bb/0xa10
 sync_filesystem+0x17a/0x230
 generic_shutdown_super+0x6f/0x2c0
 kill_block_super+0x44/0x90
 ext4_kill_sb+0x68/0xb0
 deactivate_locked_super+0xbc/0x130
 cleanup_mnt+0x425/0x4c0
 task_work_run+0x1d4/0x260
 do_exit+0x6b5/0x22e0
 do_group_exit+0x21c/0x2d0
 __x64_sys_exit_group+0x3f/0x40
 x64_sys_call+0x21ba/0x21c0
 do_syscall_64+0xfa/0x3b0
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7feb37f8e9a9
RSP: 002b:00007ffc029d0568 EFLAGS: 00000246 ORIG_RAX: 00000000000000e7
RAX: ffffffffffffffda RBX: 00007feb38010bd9 RCX: 00007feb37f8e9a9
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000001
RBP: 0000000000000027 R08: 00007ffc029ce306 R09: 00007ffc029d1820
R10: 0000000000000000 R11: 0000000000000246 R12: 00007ffc029d1820
R13: 00007feb38010b55 R14: 000055557d0164a8 R15: 00007ffc029d39e0
 </TASK>

Showing all locks held in the system:
6 locks held by kworker/0:1/10:
 #0: ffff888105231548 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: process_scheduled_works+0x9b4/0x17b0
 #1: ffffc900000d7bc0 ((work_completion)(&hub->events)){+.+.}-{0:0}, at: process_scheduled_works+0x9ef/0x17b0
 #2: ffff88810afac198 (&dev->mutex){....}-{4:4}, at: hub_event+0x184/0x4a20
 #3: ffff88810afaf510 (&port_dev->status_lock){+.+.}-{4:4}, at: hub_event+0x21b8/0x4a20
 #4: 
ffff8881084e5568
 (
hcd->address0_mutex
){+.+.}-{4:4}
, at: hub_event+0x21e5/0x4a20
 #5: ffffffff8edda890 (ehci_cf_port_reset_rwsem){.+.+}-{4:4}, at: hub_port_reset+0x163/0x1750
1 lock held by khungtaskd/34:
 #0: ffffffff8e13f0e0 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180
4 locks held by kworker/u9:5/4049:
2 locks held by getty/5657:
 #0: 
ffff8881085e90a0
 (&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
2 locks held by syz-executor/11921:
 #0: ffff8880202580e0 (&type->s_umount_key#31){++++}-{4:4}, at: deactivate_super+0xa9/0xe0
 #1: ffff8881094ae7d0 (&bdi->wb_switch_rwsem){+.+.}-{4:4}, at: sync_inodes_sb+0x19f/0xa10
5 locks held by kworker/1:6/11925:
 #0: ffff888105231548 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: process_scheduled_works+0x9b4/0x17b0
 #1: 
ffffc90003657bc0
 ((work_completion)(&hub->events)){+.+.}-{0:0}, at: process_scheduled_works+0x9ef/0x17b0
 #2: ffff88810af14198 (&dev->mutex){....}-{4:4}, at: hub_event+0x184/0x4a20
 #3: ffff88810af17510 (&port_dev->status_lock){+.+.}-{4:4}, at: hub_event+0x21b8/0x4a20
 #4: ffff8881081d5668 (hcd->address0_mutex){+.+.}-{4:4}, at: hub_event+0x21e5/0x4a20
7 locks held by syz.9.1301/14557:
2 locks held by dhcpcd/14560:
 #0: ffff88803c23a258 (sk_lock-AF_PACKET){+.+.}-{0:0}, at: packet_do_bind+0x32/0xcd0
 #1: ffffffff8e144bf8 (rcu_state.exp_mutex){+.+.}-{4:4}, at: synchronize_rcu_expedited+0x3b9/0x730

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

NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 34 Comm: khungtaskd Not tainted 6.16.0-rc7-syzkaller-dirty #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+0xfee/0x1030
 kthread+0x711/0x8a0
 ret_from_fork+0x3fc/0x770
 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: 4049 Comm: kworker/u9:5 Not tainted 6.16.0-rc7-syzkaller-dirty #0 PREEMPT(full) 
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.2-debian-1.16.2-1 04/01/2014
Workqueue: writeback wb_workfn (flush-7:7)
RIP: 0010:check_preemption_disabled+0x63/0x120
Code: 08 0f 85 cc 00 00 00 48 83 c4 10 5b 41 5e 41 5f 5d c3 cc cc cc cc cc 48 c7 04 24 00 00 00 00 9c 8f 04 24 f7 04 24 00 02 00 00 <74> c8 65 4c 8b 3c 25 08 d0 9f 92 41 f6 47 2f 04 74 0a 41 83 bf 18
RSP: 0018:ffffc9000654e738 EFLAGS: 00000046
RAX: 0000000000000000 RBX: 0000000000000202 RCX: 0000000080000000
RDX: ffffc9000654e801 RSI: ffffffff8d9a9d91 RDI: ffffffff8be28d00
RBP: dffffc0000000000 R08: ffffc9000654f240 R09: 0000000000000000
R10: ffffc9000654e8f8 R11: fffff52000ca9d21 R12: ffffc9000654f250
R13: ffffffff8172aae5 R14: ffffffff8e13f0e0 R15: ffff888021e51cc0
FS:  0000000000000000(0000) GS:ffff8880b8623000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000055d0155e59a5 CR3: 0000000124e14000 CR4: 00000000000006f0
Call Trace:
 <TASK>
 lock_release+0xbc/0x3e0
 unwind_next_frame+0x19a9/0x2390
 arch_stack_walk+0x11c/0x150
 stack_trace_save+0x9c/0xe0
 kasan_save_track+0x3e/0x80
 kasan_save_free_info+0x46/0x50
 __kasan_slab_free+0x62/0x70
 kmem_cache_free+0x18f/0x400
 ext4_put_io_end+0x15f/0x1d0
 ext4_do_writepages+0x1335/0x3f30
 ext4_writepages+0x205/0x350
 do_writepages+0x32e/0x550
 __writeback_single_inode+0x145/0xff0
 writeback_sb_inodes+0x6b5/0x1000
 wb_writeback+0x43b/0xaf0
 wb_workfn+0x409/0xef0
 process_scheduled_works+0xae1/0x17b0
 worker_thread+0x8a0/0xda0
 kthread+0x711/0x8a0
 ret_from_fork+0x3fc/0x770
 ret_from_fork_asm+0x1a/0x30
 </TASK>
