INFO: task kworker/u4:4:23929 blocked for more than 143 seconds.
      Not tainted 6.6.0-rc6-next-20231018-syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:kworker/u4:4    state:D stack:25104 pid:23929 tgid:23929 ppid:2      flags:0x00004000
Workqueue: writeback wb_workfn (flush-7:5)
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5369 [inline]
 __schedule+0xee4/0x5a10 kernel/sched/core.c:6680
 __schedule_loop kernel/sched/core.c:6757 [inline]
 schedule+0xe7/0x270 kernel/sched/core.c:6772
 io_schedule+0xbe/0x130 kernel/sched/core.c:8992
 bit_wait_io+0x16/0xe0 kernel/sched/wait_bit.c:209
 __wait_on_bit_lock+0x112/0x1a0 kernel/sched/wait_bit.c:90
 out_of_line_wait_on_bit_lock+0xdb/0x110 kernel/sched/wait_bit.c:117
 wait_on_bit_lock_io include/linux/wait_bit.h:208 [inline]
 __lock_buffer+0x67/0x70 fs/buffer.c:71
 lock_buffer include/linux/buffer_head.h:404 [inline]
 __ext4_get_inode_loc+0x10f6/0x14c0 fs/ext4/inode.c:4398
 __ext4_get_inode_loc_noinmem+0xb9/0x150 fs/ext4/inode.c:4505
 ext4_write_inode+0x314/0x540 fs/ext4/inode.c:5205
 write_inode fs/fs-writeback.c:1456 [inline]
 __writeback_single_inode+0xa84/0xe60 fs/fs-writeback.c:1673
 writeback_sb_inodes+0x5a2/0x1090 fs/fs-writeback.c:1899
 __writeback_inodes_wb+0xff/0x2d0 fs/fs-writeback.c:1970
 wb_writeback+0x7fe/0xaa0 fs/fs-writeback.c:2077
 wb_check_background_flush fs/fs-writeback.c:2147 [inline]
 wb_do_writeback fs/fs-writeback.c:2235 [inline]
 wb_workfn+0x86a/0xfd0 fs/fs-writeback.c:2262
 process_one_work+0x8a2/0x15e0 kernel/workqueue.c:2630
 process_scheduled_works kernel/workqueue.c:2703 [inline]
 worker_thread+0x8b9/0x1290 kernel/workqueue.c:2784
 kthread+0x33c/0x440 kernel/kthread.c:388
 ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:147
 ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:242
 </TASK>

Showing all locks held in the system:
1 lock held by khungtaskd/29:
 #0: ffffffff8cbacbe0 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:301 [inline]
 #0: ffffffff8cbacbe0 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:747 [inline]
 #0: ffffffff8cbacbe0 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x75/0x340 kernel/locking/lockdep.c:6613
2 locks held by kworker/u4:11/2899:
 #0: ffff8880b983c718 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0x29/0x130 kernel/sched/core.c:558
 #1: ffff8880b9828888 (&per_cpu_ptr(group->pcpu, cpu)->seq){-.-.}-{0:0}, at: psi_task_switch+0x2d9/0x900 kernel/sched/psi.c:988
2 locks held by getty/4814:
 #0: ffff888025ff10a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x24/0x80 drivers/tty/tty_ldisc.c:243
 #1: ffffc900031332f0 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0xfc6/0x1490 drivers/tty/n_tty.c:2201
1 lock held by syz-executor.0/5089:
3 locks held by kworker/u4:4/23929:
 #0: ffff88801aa7d538 ((wq_completion)writeback){+.+.}-{0:0}, at: process_one_work+0x78a/0x15e0 kernel/workqueue.c:2605
 #1: ffffc90016297d80 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_one_work+0x7f4/0x15e0 kernel/workqueue.c:2606
 #2: ffff888046a180e0 (&type->s_umount_key#32){++++}-{3:3}, at: super_trylock_shared+0x1e/0xf0 fs/super.c:610
3 locks held by syz-executor.5/31663:
1 lock held by syz-executor.4/325:
 #0: ffff8880156ec0e0 (&type->s_umount_key#51){+.+.}-{3:3}, at: __super_lock fs/super.c:56 [inline]
 #0: ffff8880156ec0e0 (&type->s_umount_key#51){+.+.}-{3:3}, at: __super_lock_excl fs/super.c:71 [inline]
 #0: ffff8880156ec0e0 (&type->s_umount_key#51){+.+.}-{3:3}, at: mount_bdev+0x1cb/0x2e0 fs/super.c:1633

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

NMI backtrace for cpu 1
CPU: 1 PID: 29 Comm: khungtaskd Not tainted 6.6.0-rc6-next-20231018-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/06/2023
Call Trace:
 <TASK>
 __dump_stack lib/dump_stack.c:88 [inline]
 dump_stack_lvl+0xd9/0x1b0 lib/dump_stack.c:106
 nmi_cpu_backtrace+0x277/0x380 lib/nmi_backtrace.c:113
 nmi_trigger_cpumask_backtrace+0x299/0x300 lib/nmi_backtrace.c:62
 trigger_all_cpu_backtrace include/linux/nmi.h:160 [inline]
 check_hung_uninterruptible_tasks kernel/hung_task.c:222 [inline]
 watchdog+0xf87/0x1210 kernel/hung_task.c:379
 kthread+0x33c/0x440 kernel/kthread.c:388
 ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:147
 ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:242
 </TASK>
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 PID: 325 Comm: syz-executor.4 Not tainted 6.6.0-rc6-next-20231018-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/06/2023
RIP: 0010:kasan_check_range+0x12/0x190 mm/kasan/generic.c:186
Code: c4 dd ff ff 89 43 08 5b 5d 41 5c c3 66 66 2e 0f 1f 84 00 00 00 00 00 90 66 0f 1f 00 48 85 f6 0f 84 48 01 00 00 48 89 f8 41 54 <44> 0f b6 c2 48 01 f0 55 53 0f 82 c6 00 00 00 48 b8 ff ff ff ff ff
RSP: 0018:ffffc90016a47988 EFLAGS: 00000202
RAX: ffff888029634a98 RBX: 00000000000000ba RCX: ffffffff83bf80c2
RDX: 0000000000000001 RSI: 0000000000000008 RDI: ffff888029634a98
RBP: 00000000000000ed R08: 0000000000000001 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000000 R12: ffff888044a1f800
R13: ffff888029634a80 R14: 0000000000000001 R15: 0000000000000001
FS:  00007f7bb2f0d6c0(0000) GS:ffff8880b9800000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007ffcce7f0c38 CR3: 000000003e777000 CR4: 00000000003506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <NMI>
 </NMI>
 <TASK>
 instrument_write include/linux/instrumented.h:40 [inline]
 ___set_bit include/asm-generic/bitops/instrumented-non-atomic.h:28 [inline]
 __set_bit_le include/asm-generic/bitops/le.h:36 [inline]
 update_free_nid_bitmap.isra.0+0x302/0x3f0 fs/f2fs/node.c:2268
 load_free_nid_bitmap fs/f2fs/node.c:3198 [inline]
 f2fs_build_node_manager+0x20b1/0x3000 fs/f2fs/node.c:3320
 f2fs_fill_super+0x4045/0xa1c0 fs/f2fs/super.c:4612
 mount_bdev+0x1f3/0x2e0 fs/super.c:1635
 legacy_get_tree+0x109/0x220 fs/fs_context.c:662
 vfs_get_tree+0x8c/0x370 fs/super.c:1756
 do_new_mount fs/namespace.c:3337 [inline]
 path_mount+0x1492/0x1ed0 fs/namespace.c:3664
 do_mount fs/namespace.c:3677 [inline]
 __do_sys_mount fs/namespace.c:3886 [inline]
 __se_sys_mount fs/namespace.c:3863 [inline]
 __x64_sys_mount+0x293/0x310 fs/namespace.c:3863
 do_syscall_x64 arch/x86/entry/common.c:51 [inline]
 do_syscall_64+0x3f/0x110 arch/x86/entry/common.c:82
 entry_SYSCALL_64_after_hwframe+0x63/0x6b
RIP: 0033:0x7f7bb227e1ea
Code: d8 64 89 02 48 c7 c0 ff ff ff ff eb a6 e8 de 09 00 00 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 49 89 ca b8 a5 00 00 00 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 b0 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007f7bb2f0cee8 EFLAGS: 00000202 ORIG_RAX: 00000000000000a5
RAX: ffffffffffffffda RBX: 00007f7bb2f0cf80 RCX: 00007f7bb227e1ea
RDX: 00000000200000c0 RSI: 0000000020000080 RDI: 00007f7bb2f0cf40
RBP: 00000000200000c0 R08: 00007f7bb2f0cf80 R09: 0000000000000010
R10: 0000000000000010 R11: 0000000000000202 R12: 0000000020000080
R13: 00007f7bb2f0cf40 R14: 0000000000007e7c R15: 0000000020000200
 </TASK>