rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 	Tasks blocked on level-0 rcu_node (CPUs 0-1): P3650/1:b..l
	(detected by 0, t=10502 jiffies, g=139601, q=77)
task:kworker/u4:6    state:R  running task     stack:21440 pid: 3650 ppid:     2 flags:0x00004000
Workqueue: netns cleanup_net
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5026 [inline]
 __schedule+0x12c4/0x4590 kernel/sched/core.c:6372
 preempt_schedule_irq+0xf7/0x1c0 kernel/sched/core.c:6776
 irqentry_exit+0x53/0x80 kernel/entry/common.c:426
 asm_sysvec_reschedule_ipi+0x16/0x20 arch/x86/include/asm/idtentry.h:643
RIP: 0010:lock_acquire+0x292/0x4f0 kernel/locking/lockdep.c:5626
Code: 11 00 00 00 00 66 43 c7 44 25 15 00 00 43 c6 44 25 17 00 65 48 8b 04 25 28 00 00 00 48 3b 84 24 00 01 00 00 0f 85 52 02 00 00 <48> 8d 65 d8 5b 41 5c 41 5d 41 5e 41 5f 5d c3 65 8b 05 c8 f9 9f 7e
RSP: 0018:ffffc900044278c0 EFLAGS: 00000246
RAX: aaf1d3e544f6e100 RBX: 1ffff92000884f24 RCX: 1ffff92000884ec4
RDX: dffffc0000000000 RSI: ffffffff8a8b1f80 RDI: ffffffff8ad87a00
RBP: ffffc90004427a20 R08: dffffc0000000000 R09: fffffbfff1f7b021
R10: 0000000000000000 R11: dffffc0000000001 R12: 1ffff92000884f20
R13: dffffc0000000000 R14: ffffc90004427920 R15: 0000000000000246
 rcu_lock_acquire+0x2a/0x30 include/linux/rcupdate.h:269
 rcu_read_lock include/linux/rcupdate.h:696 [inline]
 inet_twsk_purge+0x11e/0xa20 net/ipv4/inet_timewait_sock.c:268
 tcp_sk_exit_batch+0x28/0x90 net/ipv4/tcp_ipv4.c:3223
 ops_exit_list net/core/net_namespace.c:174 [inline]
 cleanup_net+0x763/0xb60 net/core/net_namespace.c:596
 process_one_work+0x8a1/0x10c0 kernel/workqueue.c:2310
 worker_thread+0xaca/0x1280 kernel/workqueue.c:2457
 kthread+0x3f6/0x4f0 kernel/kthread.c:319
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:298
 </TASK>
rcu: rcu_preempt kthread starved for 9781 jiffies! g139601 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x0 ->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:R  running task     stack:27000 pid:   15 ppid:     2 flags:0x00004000
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5026 [inline]
 __schedule+0x12c4/0x4590 kernel/sched/core.c:6372
 schedule+0x11b/0x1f0 kernel/sched/core.c:6455
 schedule_timeout+0x1b9/0x300 kernel/time/timer.c:1884
 rcu_gp_fqs_loop+0x2af/0xf70 kernel/rcu/tree.c:1959
 rcu_gp_kthread+0xa4/0x360 kernel/rcu/tree.c:2132
 kthread+0x3f6/0x4f0 kernel/kthread.c:319
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:298
 </TASK>
rcu: Stack dump where RCU GP kthread last ran:
NMI backtrace for cpu 0
CPU: 0 PID: 0 Comm: swapper/0 Not tainted 5.15.128-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/26/2023
Call Trace:
 <IRQ>
 __dump_stack lib/dump_stack.c:88 [inline]
 dump_stack_lvl+0x1e3/0x2cb 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_single_cpu_backtrace include/linux/nmi.h:166 [inline]
 rcu_check_gp_kthread_starvation+0x1d2/0x240 kernel/rcu/tree_stall.h:481
 print_other_cpu_stall+0x137a/0x14d0 kernel/rcu/tree_stall.h:586
 check_cpu_stall kernel/rcu/tree_stall.h:729 [inline]
 rcu_pending kernel/rcu/tree.c:3911 [inline]
 rcu_sched_clock_irq+0x94f/0x1770 kernel/rcu/tree.c:2606
 update_process_times+0x196/0x200 kernel/time/timer.c:1788
 tick_sched_handle kernel/time/tick-sched.c:254 [inline]
 tick_sched_timer+0x386/0x550 kernel/time/tick-sched.c:1473
 __run_hrtimer kernel/time/hrtimer.c:1685 [inline]
 __hrtimer_run_queues+0x55b/0xcf0 kernel/time/hrtimer.c:1749
 hrtimer_interrupt+0x392/0x980 kernel/time/hrtimer.c:1811
 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1085 [inline]
 __sysvec_apic_timer_interrupt+0x139/0x470 arch/x86/kernel/apic/apic.c:1102
 sysvec_apic_timer_interrupt+0x8c/0xb0 arch/x86/kernel/apic/apic.c:1096
 </IRQ>
 <TASK>
 asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:638
RIP: 0010:native_save_fl arch/x86/include/asm/irqflags.h:22 [inline]
RIP: 0010:arch_local_save_flags arch/x86/include/asm/irqflags.h:70 [inline]
RIP: 0010:arch_irqs_disabled arch/x86/include/asm/irqflags.h:132 [inline]
RIP: 0010:acpi_safe_halt drivers/acpi/processor_idle.c:110 [inline]
RIP: 0010:acpi_idle_do_entry+0x10f/0x340 drivers/acpi/processor_idle.c:570
Code: 17 5a f7 48 83 e3 08 0f 85 0a 01 00 00 4c 8d 74 24 20 e8 e4 89 60 f7 0f 1f 44 00 00 e8 1a 13 5a f7 0f 00 2d 13 78 bc 00 fb f4 <4c> 89 f3 48 c1 eb 03 42 80 3c 3b 00 74 08 4c 89 f7 e8 bb b3 a3 f7
RSP: 0018:ffffffff8c607b80 EFLAGS: 000002d3
RAX: ffffffff8a2600c6 RBX: 0000000000000000 RCX: ffffffff8c6bd5c0
RDX: 0000000000000000 RSI: ffffffff8a8b0ce0 RDI: ffffffff8ad87a00
RBP: ffffffff8c607c10 R08: ffffffff81868ad0 R09: fffffbfff18d7ab9
R10: 0000000000000000 R11: dffffc0000000001 R12: 1ffffffff18c0f70
R13: ffff888146425804 R14: ffffffff8c607ba0 R15: dffffc0000000000
 acpi_idle_enter+0x352/0x4f0 drivers/acpi/processor_idle.c:705
 cpuidle_enter_state+0x521/0xef0 drivers/cpuidle/cpuidle.c:237
 cpuidle_enter+0x59/0x90 drivers/cpuidle/cpuidle.c:351
 call_cpuidle kernel/sched/idle.c:158 [inline]
 cpuidle_idle_call kernel/sched/idle.c:239 [inline]
 do_idle+0x3e4/0x670 kernel/sched/idle.c:306
 cpu_startup_entry+0x14/0x20 kernel/sched/idle.c:403
 start_kernel+0x48c/0x535 init/main.c:1133
 secondary_startup_64_no_verify+0xb1/0xbb
 </TASK>