INFO: task kworker/u4:0:8 blocked for more than 143 seconds.
      Not tainted 5.19.0-rc4-next-20220628-syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:kworker/u4:0    state:D stack:26096 pid:    8 ppid:     2 flags:0x00004000
Workqueue: writeback wb_workfn (flush-7:5)
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5184 [inline]
 __schedule+0xa09/0x4f10 kernel/sched/core.c:6496
 schedule+0xd2/0x1f0 kernel/sched/core.c:6568
 schedule_timeout+0x1db/0x2a0 kernel/time/timer.c:1911
 do_wait_for_common kernel/sched/completion.c:85 [inline]
 __wait_for_common+0x378/0x530 kernel/sched/completion.c:106
 f2fs_issue_checkpoint+0x363/0x460 fs/f2fs/checkpoint.c:1865
 f2fs_sync_fs+0x2f9/0x420 fs/f2fs/super.c:1653
 f2fs_balance_fs_bg+0xc6a/0xef0 fs/f2fs/segment.c:477
 f2fs_write_node_pages+0x148/0xc40 fs/f2fs/node.c:2100
 do_writepages+0x1ab/0x690 mm/page-writeback.c:2468
 __writeback_single_inode+0x121/0x10b0 fs/fs-writeback.c:1588
 writeback_sb_inodes+0x54d/0xf10 fs/fs-writeback.c:1866
 __writeback_inodes_wb+0xc6/0x280 fs/fs-writeback.c:1937
 wb_writeback+0x7e9/0xc20 fs/fs-writeback.c:2042
 wb_check_old_data_flush fs/fs-writeback.c:2142 [inline]
 wb_do_writeback fs/fs-writeback.c:2195 [inline]
 wb_workfn+0x845/0x1230 fs/fs-writeback.c:2223
 process_one_work+0x991/0x1610 kernel/workqueue.c:2289
 worker_thread+0x665/0x1080 kernel/workqueue.c:2436
 kthread+0x2e9/0x3a0 kernel/kthread.c:376
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:302
 </TASK>

Showing all locks held in the system:
3 locks held by kworker/u4:0/8:
 #0: ffff888145b3c938 ((wq_completion)writeback){+.+.}-{0:0}, at: arch_atomic64_set arch/x86/include/asm/atomic64_64.h:34 [inline]
 #0: ffff888145b3c938 ((wq_completion)writeback){+.+.}-{0:0}, at: arch_atomic_long_set include/linux/atomic/atomic-long.h:41 [inline]
 #0: ffff888145b3c938 ((wq_completion)writeback){+.+.}-{0:0}, at: atomic_long_set include/linux/atomic/atomic-instrumented.h:1280 [inline]
 #0: ffff888145b3c938 ((wq_completion)writeback){+.+.}-{0:0}, at: set_work_data kernel/workqueue.c:636 [inline]
 #0: ffff888145b3c938 ((wq_completion)writeback){+.+.}-{0:0}, at: set_work_pool_and_clear_pending kernel/workqueue.c:663 [inline]
 #0: ffff888145b3c938 ((wq_completion)writeback){+.+.}-{0:0}, at: process_one_work+0x87a/0x1610 kernel/workqueue.c:2260
 #1: ffffc900000d7da8 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_one_work+0x8ae/0x1610 kernel/workqueue.c:2264
 #2: ffff88807487e0e0 (&type->s_umount_key#102){++++}-{3:3}, at: trylock_super+0x1d/0x100 fs/super.c:415
1 lock held by rcu_tasks_kthre/12:
 #0: ffffffff8bd864f0 (rcu_tasks.tasks_gp_mutex){+.+.}-{3:3}, at: rcu_tasks_one_gp+0x26/0xc70 kernel/rcu/tasks.h:507
1 lock held by rcu_tasks_trace/13:
 #0: ffffffff8bd861f0 (rcu_tasks_trace.tasks_gp_mutex){+.+.}-{3:3}, at: rcu_tasks_one_gp+0x26/0xc70 kernel/rcu/tasks.h:507
1 lock held by khungtaskd/28:
 #0: ffffffff8bd87040 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x53/0x260 kernel/locking/lockdep.c:6491
2 locks held by getty/3283:
 #0: ffff88802604d098 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x22/0x80 drivers/tty/tty_ldisc.c:244
 #1: ffffc90002d162f0 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0xe50/0x13c0 drivers/tty/n_tty.c:2177
3 locks held by kworker/u4:13/10068:
2 locks held by kworker/0:13/13551:
 #0: ffff888011866538 ((wq_completion)rcu_gp){+.+.}-{0:0}, at: arch_atomic64_set arch/x86/include/asm/atomic64_64.h:34 [inline]
 #0: ffff888011866538 ((wq_completion)rcu_gp){+.+.}-{0:0}, at: arch_atomic_long_set include/linux/atomic/atomic-long.h:41 [inline]
 #0: ffff888011866538 ((wq_completion)rcu_gp){+.+.}-{0:0}, at: atomic_long_set include/linux/atomic/atomic-instrumented.h:1280 [inline]
 #0: ffff888011866538 ((wq_completion)rcu_gp){+.+.}-{0:0}, at: set_work_data kernel/workqueue.c:636 [inline]
 #0: ffff888011866538 ((wq_completion)rcu_gp){+.+.}-{0:0}, at: set_work_pool_and_clear_pending kernel/workqueue.c:663 [inline]
 #0: ffff888011866538 ((wq_completion)rcu_gp){+.+.}-{0:0}, at: process_one_work+0x87a/0x1610 kernel/workqueue.c:2260
 #1: ffffc90015547da8 ((work_completion)(&rew->rew_work)){+.+.}-{0:0}, at: process_one_work+0x8ae/0x1610 kernel/workqueue.c:2264
4 locks held by kworker/u4:15/17643:
2 locks held by f2fs_ckpt-7:5/26816:
3 locks held by kworker/0:4/31896:
 #0: ffff888011864d38 ((wq_completion)events){+.+.}-{0:0}, at: arch_atomic64_set arch/x86/include/asm/atomic64_64.h:34 [inline]
 #0: ffff888011864d38 ((wq_completion)events){+.+.}-{0:0}, at: arch_atomic_long_set include/linux/atomic/atomic-long.h:41 [inline]
 #0: ffff888011864d38 ((wq_completion)events){+.+.}-{0:0}, at: atomic_long_set include/linux/atomic/atomic-instrumented.h:1280 [inline]
 #0: ffff888011864d38 ((wq_completion)events){+.+.}-{0:0}, at: set_work_data kernel/workqueue.c:636 [inline]
 #0: ffff888011864d38 ((wq_completion)events){+.+.}-{0:0}, at: set_work_pool_and_clear_pending kernel/workqueue.c:663 [inline]
 #0: ffff888011864d38 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work+0x87a/0x1610 kernel/workqueue.c:2260
 #1: ffffc900030efda8 (fqdir_free_work){+.+.}-{0:0}, at: process_one_work+0x8ae/0x1610 kernel/workqueue.c:2264
 #2: ffffffff8bd91800 (rcu_state.barrier_mutex){+.+.}-{3:3}, at: rcu_barrier+0x44/0x630 kernel/rcu/tree.c:3783
2 locks held by syz-executor.3/32564:
 #0: ffffffff8d58ea10 (pernet_ops_rwsem){++++}-{3:3}, at: copy_net_ns+0x2f5/0x760 net/core/net_namespace.c:468
 #1: ffffffff8bd91938 (rcu_state.exp_mutex){+.+.}-{3:3}, at: exp_funnel_lock kernel/rcu/tree_exp.h:292 [inline]
 #1: ffffffff8bd91938 (rcu_state.exp_mutex){+.+.}-{3:3}, at: synchronize_rcu_expedited+0x562/0x670 kernel/rcu/tree_exp.h:940

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

NMI backtrace for cpu 1
CPU: 1 PID: 28 Comm: khungtaskd Not tainted 5.19.0-rc4-next-20220628-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/22/2022
Call Trace:
 <TASK>
 __dump_stack lib/dump_stack.c:88 [inline]
 dump_stack_lvl+0xcd/0x134 lib/dump_stack.c:106
 nmi_cpu_backtrace.cold+0x47/0x144 lib/nmi_backtrace.c:111
 nmi_trigger_cpumask_backtrace+0x1e6/0x230 lib/nmi_backtrace.c:62
 trigger_all_cpu_backtrace include/linux/nmi.h:146 [inline]
 check_hung_uninterruptible_tasks kernel/hung_task.c:212 [inline]
 watchdog+0xc18/0xf50 kernel/hung_task.c:369
 kthread+0x2e9/0x3a0 kernel/kthread.c:376
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:302
 </TASK>
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 PID: 32564 Comm: syz-executor.3 Not tainted 5.19.0-rc4-next-20220628-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/22/2022
RIP: 0010:native_save_fl arch/x86/include/asm/irqflags.h:29 [inline]
RIP: 0010:arch_local_save_flags arch/x86/include/asm/irqflags.h:70 [inline]
RIP: 0010:check_preemption_disabled+0x4c/0x170 lib/smp_processor_id.c:19
Code: 81 e3 ff ff ff 7f 31 ff 89 de 0f 1f 44 00 00 85 db 74 11 0f 1f 44 00 00 44 89 e0 5b 5d 41 5c 41 5d 41 5e c3 0f 1f 44 00 00 9c <5b> 81 e3 00 02 00 00 31 ff 48 89 de 0f 1f 44 00 00 48 85 db 74 d3
RSP: 0018:ffffc9000324fad8 EFLAGS: 00000046
RAX: 0000000000000000 RBX: 0000000000000000 RCX: 0000000000000001
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000
RBP: ffffffff8a2874e0 R08: 0000000000000004 R09: 000000000000ffff
R10: 0000000000004181 R11: 0000000000000001 R12: 0000000000000000
R13: ffffffff89cc8900 R14: 00000000ffffffff R15: ffff88803dd644d0
FS:  00007f13f4c5d700(0000) GS:ffff8880b9a00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000000c0098deea8 CR3: 00000000760f5000 CR4: 00000000003506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <TASK>
 lockdep_recursion_finish kernel/locking/lockdep.c:466 [inline]
 lock_is_held_type+0xd7/0x140 kernel/locking/lockdep.c:5709
 lock_is_held include/linux/lockdep.h:279 [inline]
 __might_resched+0x3a/0x2c0 kernel/sched/core.c:9821
 inet_twsk_purge+0xe8/0x850 net/ipv4/inet_timewait_sock.c:268
 tcp_sk_exit_batch+0x1d/0xa0 net/ipv4/tcp_ipv4.c:3179
 ops_exit_list+0x125/0x170 net/core/net_namespace.c:168
 setup_net+0x7fb/0xc50 net/core/net_namespace.c:349
 copy_net_ns+0x318/0x760 net/core/net_namespace.c:472
 create_new_namespaces+0x3f6/0xb20 kernel/nsproxy.c:110
 unshare_nsproxy_namespaces+0xc1/0x1f0 kernel/nsproxy.c:227
 ksys_unshare+0x445/0x920 kernel/fork.c:3162
 __do_sys_unshare kernel/fork.c:3233 [inline]
 __se_sys_unshare kernel/fork.c:3231 [inline]
 __x64_sys_unshare+0x2d/0x40 kernel/fork.c:3231
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x35/0xb0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x46/0xb0
RIP: 0033:0x7f13f3a89209
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 b8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007f13f4c5d168 EFLAGS: 00000246 ORIG_RAX: 0000000000000110
RAX: ffffffffffffffda RBX: 00007f13f3b9bf60 RCX: 00007f13f3a89209
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000040000480
RBP: 00007f13f3ae3161 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007ffcd8d6460f R14: 00007f13f4c5d300 R15: 0000000000022000
 </TASK>