INFO: task syz-executor:5848 blocked for more than 143 seconds.
      Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz-executor    state:D stack:21832 pid:5848  tgid:5848  ppid:1      task_flags:0x400140 flags:0x00004004
Call Trace:
 <TASK>
 __schedule+0x1798/0x4cc0
 schedule+0x165/0x360
 wb_wait_for_completion+0x15f/0x260
 __writeback_inodes_sb_nr+0x1f6/0x250
 sync_filesystem+0xa3/0x230
 generic_shutdown_super+0x6f/0x2c0
 bch2_kill_sb+0x41/0x50
 deactivate_locked_super+0xbc/0x130
 cleanup_mnt+0x425/0x4c0
 task_work_run+0x1d4/0x260
 exit_to_user_mode_loop+0xec/0x110
 do_syscall_64+0x2bd/0x3b0
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fd1ff78ff17
RSP: 002b:00007ffeb848b798 EFLAGS: 00000246 ORIG_RAX: 00000000000000a6
RAX: 0000000000000000 RBX: 00007fd1ff811c05 RCX: 00007fd1ff78ff17
RDX: 0000000000000000 RSI: 0000000000000009 RDI: 00007ffeb848b850
RBP: 00007ffeb848b850 R08: 0000000000000000 R09: 0000000000000000
R10: 00000000ffffffff R11: 0000000000000246 R12: 00007ffeb848c8e0
R13: 00007fd1ff811c05 R14: 0000000000011f15 R15: 00007ffeb848c920
 </TASK>

Showing all locks held in the system:
2 locks held by kworker/u10:0/27:
1 lock held by khungtaskd/34:
 #0: ffffffff8e139ee0 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180
2 locks held by kworker/u9:4/3976:
 #0: ffff888100154948 ((wq_completion)writeback){+.+.}-{0:0}, at: process_scheduled_works+0x9b4/0x17b0
 #1: ffffc90008d27bc0 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_scheduled_works+0x9ef/0x17b0
2 locks held by getty/5676:
 #0: ffff88801b6e90a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70
 #1: ffffc900029032f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x43e/0x1400
1 lock held by syz-executor/5848:
 #0: ffff888021bd40e0 (&type->s_umount_key#53){++++}-{4:4}, at: deactivate_super+0xa9/0xe0
1 lock held by syz.6.200/7738:
 #0: ffff888021bd40e0 (&type->s_umount_key#53){++++}-{4:4}, at: super_lock+0x2a9/0x3b0
1 lock held by syz.6.200/7755:
 #0: ffff888021bd40e0 (&type->s_umount_key#53){++++}-{4:4}, at: super_lock+0x2a9/0x3b0
1 lock held by syz.2.369/9417:
 #0: ffff888021bd40e0 (&type->s_umount_key#53){++++}-{4:4}, at: super_lock+0x2a9/0x3b0
3 locks held by syz.5.493/10313:
3 locks held by syz.4.495/10316:
2 locks held by syz.6.496/10317:

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

NMI backtrace for cpu 0
CPU: 0 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+0x189/0x250
 nmi_cpu_backtrace+0x39e/0x3d0
 nmi_trigger_cpumask_backtrace+0x17a/0x300
 watchdog+0xf93/0xfe0
 kthread+0x711/0x8a0
 ret_from_fork+0x3fc/0x770
 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: 10316 Comm: syz.4.495 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:debug_smp_processor_id+0x0/0x20
Code: c7 40 36 1f 8e 4c 89 f6 e8 ed 99 85 f9 e9 66 ff ff ff cc cc cc cc cc cc cc cc 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 <f3> 0f 1e fa 48 c7 c7 20 36 e3 8b 48 c7 c6 60 36 e3 8b eb 1c 66 66
RSP: 0018:ffffc90002eeefa8 EFLAGS: 00000283
RAX: 0000000000000001 RBX: ffffffff9037b801 RCX: a9f9e3a8bd4cd900
RDX: ffffc90002eef101 RSI: ffffffff8172c195 RDI: ffffffff8e139ee0
RBP: dffffc0000000000 R08: ffffc90002eef230 R09: 0000000000000000
R10: ffffc90002eef158 R11: fffff520005dde2d R12: ffffc90002eef240
R13: ffffffff8172c195 R14: ffffffff8e139ee0 R15: ffffffff8172c195
FS:  00007f1367ddb6c0(0000) GS:ffff8881a3c1b000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f3949bbd000 CR3: 00000000410d8000 CR4: 00000000000006f0
Call Trace:
 <TASK>
 rcu_is_watching+0x15/0xb0
 lock_release+0x4b/0x3e0
 unwind_next_frame+0x19a9/0x2390
 arch_stack_walk+0x11c/0x150
 stack_trace_save+0x9c/0xe0
 save_stack+0xf5/0x1f0
 __set_page_owner+0x8d/0x4a0
 post_alloc_hook+0x240/0x2a0
 get_page_from_freelist+0x21e4/0x22c0
 __alloc_frozen_pages_noprof+0x181/0x370
 alloc_pages_mpol+0x232/0x4a0
 folio_alloc_mpol_noprof+0x39/0x70
 shmem_alloc_and_add_folio+0x447/0xf60
 shmem_get_folio_gfp+0x59d/0x1660
 shmem_write_begin+0xf7/0x2b0
 generic_perform_write+0x2c5/0x900
 shmem_file_write_iter+0xf8/0x120
 vfs_write+0x5c9/0xb30
 ksys_write+0x145/0x250
 do_syscall_64+0xfa/0x3b0
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f1366f8d69f
Code: 89 54 24 18 48 89 74 24 10 89 7c 24 08 e8 f9 92 02 00 48 8b 54 24 18 48 8b 74 24 10 41 89 c0 8b 7c 24 08 b8 01 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 31 44 89 c7 48 89 44 24 08 e8 4c 93 02 00 48
RSP: 002b:00007f1367ddadf0 EFLAGS: 00000293 ORIG_RAX: 0000000000000001
RAX: ffffffffffffffda RBX: 0000000001000000 RCX: 00007f1366f8d69f
RDX: 0000000001000000 RSI: 00007f135cc00000 RDI: 0000000000000003
RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000004427
R10: 0000000000000002 R11: 0000000000000293 R12: 0000000000000003
R13: 00007f1367ddaef0 R14: 00007f1367ddaeb0 R15: 00007f135cc00000
 </TASK>
