INFO: task kworker/u4:4:1172 blocked for more than 143 seconds.
      Not tainted 5.15.175-syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:kworker/u4:4    state:D stack:24664 pid: 1172 ppid:     2 flags:0x00004000
Workqueue: writeback wb_workfn (flush-7:0)
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5027 [inline]
 __schedule+0x12c4/0x45b0 kernel/sched/core.c:6373
 schedule+0x11b/0x1f0 kernel/sched/core.c:6456
 rwsem_down_write_slowpath+0xf0c/0x16a0 kernel/locking/rwsem.c:1165
 f2fs_balance_fs+0x4d4/0x6a0 fs/f2fs/segment.c:528
 f2fs_write_inode+0x4be/0x660 fs/f2fs/inode.c:738
 write_inode fs/fs-writeback.c:1495 [inline]
 __writeback_single_inode+0x644/0xe30 fs/fs-writeback.c:1705
 writeback_sb_inodes+0xbce/0x1a40 fs/fs-writeback.c:1930
 __writeback_inodes_wb+0x114/0x400 fs/fs-writeback.c:2001
 wb_writeback+0x465/0xc50 fs/fs-writeback.c:2106
 wb_check_background_flush fs/fs-writeback.c:2172 [inline]
 wb_do_writeback fs/fs-writeback.c:2260 [inline]
 wb_workfn+0xd07/0x1130 fs/fs-writeback.c:2288
 process_one_work+0x8a1/0x10c0 kernel/workqueue.c:2310
 worker_thread+0xaca/0x1280 kernel/workqueue.c:2457
 kthread+0x3f6/0x4f0 kernel/kthread.c:334
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:287
 </TASK>

Showing all locks held in the system:
2 locks held by kworker/u4:0/9:
 #0: ffff8880b8e3a318 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0x26/0x140 kernel/sched/core.c:475
 #1: ffff8880b8e27848 (&per_cpu_ptr(group->pcpu, cpu)->seq){-.-.}-{0:0}, at: psi_task_switch+0x53d/0x810 kernel/sched/psi.c:891
1 lock held by khungtaskd/27:
 #0: ffffffff8cb1fd20 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire+0x0/0x30
4 locks held by kworker/u4:4/1172:
 #0: ffff888144394138 ((wq_completion)writeback){+.+.}-{0:0}, at: process_one_work+0x78a/0x10c0 kernel/workqueue.c:2283
 #1: ffffc90004a37d20 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_one_work+0x7d0/0x10c0 kernel/workqueue.c:2285
 #2: ffff88807ab340e0 (&type->s_umount_key#52){.+.+}-{3:3}, at: trylock_super+0x1b/0xf0 fs/super.c:418
 #3: ffff888076a591b0 (&sbi->gc_lock){+.+.}-{3:3}, at: f2fs_balance_fs+0x4d4/0x6a0 fs/f2fs/segment.c:528
2 locks held by getty/3931:
 #0: ffff88807f1c2098 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x21/0x70 drivers/tty/tty_ldisc.c:252
 #1: ffffc900025c62e8 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0x6af/0x1db0 drivers/tty/n_tty.c:2158
6 locks held by syz.0.15/5165:

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

NMI backtrace for cpu 1
CPU: 1 PID: 27 Comm: khungtaskd Not tainted 5.15.175-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024
Call Trace:
 <TASK>
 __dump_stack lib/dump_stack.c:88 [inline]
 dump_stack_lvl+0x1e3/0x2d0 lib/dump_stack.c:106
 nmi_cpu_backtrace+0x46a/0x4a0 lib/nmi_backtrace.c:111
 nmi_trigger_cpumask_backtrace+0x181/0x2a0 lib/nmi_backtrace.c:62
 trigger_all_cpu_backtrace include/linux/nmi.h:148 [inline]
 check_hung_uninterruptible_tasks kernel/hung_task.c:210 [inline]
 watchdog+0xe72/0xeb0 kernel/hung_task.c:295
 kthread+0x3f6/0x4f0 kernel/kthread.c:334
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:287
 </TASK>
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 PID: 5481 Comm: syz.0.161 Not tainted 5.15.175-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024
RIP: 0010:unwind_get_return_address+0x25/0x80 arch/x86/kernel/unwind_orc.c:320
Code: 47 06 09 66 90 41 57 41 56 53 48 89 fb 49 be 00 00 00 00 00 fc ff df 48 89 f8 48 c1 e8 03 42 0f b6 04 30 84 c0 75 47 83 3b 00 <74> 3a 48 83 c3 48 49 89 df 49 c1 ef 03 43 80 3c 37 00 74 08 48 89
RSP: 0018:ffffc900040d6b60 EFLAGS: 00000202
RAX: 0000000000000000 RBX: ffffc900040d6b80 RCX: 0000000080000000
RDX: dffffc0000000000 RSI: ffffc900040d6c10 RDI: ffffc900040d6b80
RBP: ffffc900040d6c10 R08: ffffc900040d6c10 R09: ffffc900040d6bd0
R10: 0000000000000000 R11: dffffc0000000001 R12: ffff88801e0c1dc0
R13: ffffffff816e19d0 R14: dffffc0000000000 R15: 0000000000000000
FS:  00007f4a459cd6c0(0000) GS:ffff8880b8e00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000001b2ee20210 CR3: 0000000077c07000 CR4: 00000000003506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <NMI>
 </NMI>
 <TASK>
 arch_stack_walk+0xf3/0x140 arch/x86/kernel/stacktrace.c:26
 stack_trace_save+0x113/0x1c0 kernel/stacktrace.c:122
 save_stack+0xf6/0x1e0 mm/page_owner.c:119
 __set_page_owner+0x37/0x300 mm/page_owner.c:181
 prep_new_page mm/page_alloc.c:2426 [inline]
 get_page_from_freelist+0x3b78/0x3d40 mm/page_alloc.c:4192
 __alloc_pages+0x272/0x700 mm/page_alloc.c:5465
 alloc_pages_vma+0x39a/0x800 mm/mempolicy.c:2146
 shmem_alloc_page mm/shmem.c:1586 [inline]
 shmem_alloc_and_acct_page+0x4d1/0xd10 mm/shmem.c:1611
 shmem_getpage_gfp+0x17b1/0x3190 mm/shmem.c:1906
 shmem_getpage mm/shmem.c:151 [inline]
 shmem_fallocate+0x914/0xfb0 mm/shmem.c:2758
 vfs_fallocate+0x54a/0x6b0 fs/open.c:308
 do_vfs_ioctl+0x2317/0x2b70 fs/ioctl.c:853
 __do_sys_ioctl fs/ioctl.c:872 [inline]
 __se_sys_ioctl+0x81/0x160 fs/ioctl.c:860
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x3b/0xb0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x66/0xd0
RIP: 0033:0x7f4a4674cff9
Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 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:00007f4a459cd038 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 00007f4a46904f80 RCX: 00007f4a4674cff9
RDX: 00000000200000c0 RSI: 0000000040305828 RDI: 0000000000000003
RBP: 00007f4a467bf296 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 0000000000000000 R14: 00007f4a46904f80 R15: 00007ffe1c36a1b8
 </TASK>