rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 	Tasks blocked on level-0 rcu_node (CPUs 0-1): P56/1:b..l
	(detected by 0, t=10502 jiffies, g=22629, q=9 ncpus=2)
task:kworker/u4:4    state:R  running task     stack:24448 pid:56    ppid:2      flags:0x00004000
Workqueue: netns cleanup_net
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5293 [inline]
 __schedule+0x9d1/0xe40 kernel/sched/core.c:6606
 preempt_schedule_irq+0xf7/0x1c0 kernel/sched/core.c:6918
 irqentry_exit+0x53/0x80 kernel/entry/common.c:432
 asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:649
RIP: 0010:lock_acquire+0x21e/0x400 kernel/locking/lockdep.c:5672
Code: 23 00 74 08 4c 89 f7 e8 30 fd 77 00 f6 44 24 61 02 0f 85 76 01 00 00 41 f7 c7 00 02 00 00 74 01 fb 48 c7 44 24 40 0e 36 e0 45 <4b> c7 04 2c 00 00 00 00 43 c7 44 2c 09 00 00 00 00 43 c7 44 2c 11
RSP: 0018:ffffc900015778c0 EFLAGS: 00000206
RAX: 0000000000000001 RBX: 1ffff920002aef24 RCX: ffff888017f961f0
RDX: dffffc0000000000 RSI: ffffffff8b0daae0 RDI: ffffffff8b697500
RBP: ffffc90001577a20 R08: dffffc0000000000 R09: fffffbfff212e631
R10: fffffbfff212e631 R11: 1ffffffff212e630 R12: dffffc0000000000
R13: 1ffff920002aef20 R14: ffffc90001577920 R15: 0000000000000246
 rcu_lock_acquire+0x2a/0x30 include/linux/rcupdate.h:325
 rcu_read_lock include/linux/rcupdate.h:764 [inline]
 inet_twsk_purge+0x12b/0x980 net/ipv4/inet_timewait_sock.c:295
 ops_exit_list net/core/net_namespace.c:174 [inline]
 cleanup_net+0x80c/0xc60 net/core/net_namespace.c:606
 process_one_work+0x81c/0xd10 kernel/workqueue.c:2289
 worker_thread+0xb14/0x1330 kernel/workqueue.c:2436
 kthread+0x266/0x300 kernel/kthread.c:376
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:308
 </TASK>
rcu: rcu_preempt kthread starved for 10114 jiffies! g22629 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x402 ->cpu=0
rcu: 	Unless rcu_preempt kthread gets sufficient CPU time, OOM is now expected behavior.
rcu: RCU grace-period kthread stack dump:
task:rcu_preempt     state:I stack:26240 pid:16    ppid:2      flags:0x00004000
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5293 [inline]
 __schedule+0x9d1/0xe40 kernel/sched/core.c:6606
 preempt_schedule_common+0x93/0xe0 kernel/sched/core.c:6775
 preempt_schedule+0xd9/0xe0 kernel/sched/core.c:6799
 preempt_schedule_thunk+0x16/0x20 arch/x86/entry/thunk_64.S:34
 __raw_spin_unlock_irqrestore include/linux/spinlock_api_smp.h:152 [inline]
 _raw_spin_unlock_irqrestore+0x128/0x130 kernel/locking/spinlock.c:194
 __debug_object_init+0x847/0x18e0 lib/debugobjects.c:609
 init_timer_on_stack_key kernel/time/timer.c:805 [inline]
 schedule_timeout+0x11d/0x300 kernel/time/timer.c:2165
 rcu_gp_fqs_loop+0x309/0x1070 kernel/rcu/tree.c:1656
 rcu_gp_kthread+0xa5/0x390 kernel/rcu/tree.c:1855
 kthread+0x266/0x300 kernel/kthread.c:376
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:308
 </TASK>
rcu: Stack dump where RCU GP kthread last ran:
CPU: 0 PID: 0 Comm: swapper/0 Not tainted 6.2.0-rc5-syzkaller-00047-g7c46948a6e9c #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/12/2023
RIP: 0010:finish_lock_switch+0x90/0x100 kernel/sched/core.c:5053
Code: 45 31 c9 68 06 c2 62 81 e8 cd ec 09 00 48 83 c4 08 4c 89 ff e8 b1 b8 fe ff eb 32 4c 89 ff e8 e7 07 6d 09 e8 72 ec 31 00 fb 5b <41> 5c 41 5d 41 5e 41 5f c3 44 89 f1 80 e1 07 80 c1 03 38 c1 7c 87
RSP: 0018:ffffffff8d207b98 EFLAGS: 00000286
RAX: 269f601a9e3f0f00 RBX: ffff888022ee1d74 RCX: ffffffff9216b003
RDX: dffffc0000000000 RSI: ffffffff8b0d9960 RDI: ffffffff8b697500
RBP: ffffffff8d207c10 R08: dffffc0000000000 R09: ffffed1017307439
R10: ffffed1017307439 R11: 1ffff11017307438 R12: dffffc0000000000
R13: 1ffff110173075e3 R14: ffff8880b983af18 R15: ffff8880b983a1c0
FS:  0000000000000000(0000) GS:ffff8880b9800000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000000c00075510c CR3: 0000000027748000 CR4: 00000000003506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <TASK>
 finish_task_switch+0x140/0x610 kernel/sched/core.c:5170
 context_switch kernel/sched/core.c:5296 [inline]
 __schedule+0x9d9/0xe40 kernel/sched/core.c:6606
 schedule_idle+0x50/0x90 kernel/sched/core.c:6710
 do_idle+0x639/0x680 kernel/sched/idle.c:331
 cpu_startup_entry+0x15/0x20 kernel/sched/idle.c:400
 rest_init+0x24f/0x270 init/main.c:732
 arch_call_rest_init+0xa/0x10 init/main.c:894
 start_kernel+0x48e/0x540 init/main.c:1148
 secondary_startup_64_no_verify+0xcf/0xdb
 </TASK>