rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 	0-...0: (1 GPs behind) idle=a1d/1/0x4000000000000000 softirq=242921/242928 fqs=2100 
	(detected by 1, t=10505 jiffies, g=336533, q=17658)
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 PID: 9562 Comm: kworker/u4:6 Not tainted 5.15.127-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/26/2023
Workqueue: netns cleanup_net
RIP: 0010:rb_erase+0x3/0xe20 lib/rbtree.c:441
Code: 5d c3 4c 89 fd 48 89 e8 48 c1 e8 03 42 80 3c 20 00 74 08 48 89 ef e8 ac cd 9e fd 48 c7 45 00 01 00 00 00 eb ce 66 90 55 41 57 <41> 56 41 55 41 54 53 48 83 ec 28 48 89 74 24 18 48 89 fb 48 b9 00
RSP: 0018:ffffc90000007d10 EFLAGS: 00000046
RAX: 0000000000000000 RBX: ffff8880b9a2a358 RCX: ffff8880ae49d940
RDX: 0000000000010001 RSI: ffff8880b9a2a350 RDI: ffff88807ba70b40
RBP: dffffc0000000000 R08: ffffffff842b9114 R09: fffffbfff1bc80ee
R10: 0000000000000000 R11: dffffc0000000001 R12: 1ffff1100f74e168
R13: ffff88807ba70b40 R14: ffff8880b9a2a350 R15: 1ffff1101734546b
FS:  0000000000000000(0000) GS:ffff8880b9a00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f909b142bd0 CR3: 00000000865e4000 CR4: 00000000003506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <NMI>
 </NMI>
 <IRQ>
 rb_erase_cached include/linux/rbtree.h:126 [inline]
 timerqueue_del+0xa8/0xf0 lib/timerqueue.c:57
 __remove_hrtimer kernel/time/hrtimer.c:1116 [inline]
 __run_hrtimer kernel/time/hrtimer.c:1665 [inline]
 __hrtimer_run_queues+0x3e9/0xcf0 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:lock_is_held_type+0x137/0x180
Code: 75 40 48 c7 04 24 00 00 00 00 9c 8f 04 24 f7 04 24 00 02 00 00 75 46 41 f7 c4 00 02 00 00 74 01 fb 65 48 8b 04 25 28 00 00 00 <48> 3b 44 24 08 75 3c 89 e8 48 83 c4 10 5b 41 5c 41 5d 41 5e 41 5f
RSP: 0018:ffffc900114bf8f8 EFLAGS: 00000206
RAX: 54c0776e714c2e00 RBX: 0000000000000003 RCX: ffff8880ae49d940
RDX: 0000000000000000 RSI: ffffffff8a8b1f00 RDI: ffffffff8ad87900
RBP: 0000000000000000 R08: dffffc0000000000 R09: fffffbfff1bc80ee
R10: 0000000000000000 R11: dffffc0000000001 R12: 0000000000000246
R13: ffff8880ae49d940 R14: 00000000ffffffff R15: ffffffff8c91f100
 lock_is_held include/linux/lockdep.h:287 [inline]
 ___might_sleep+0xa2/0x6a0 kernel/sched/core.c:9591
 inet_twsk_purge+0x10f/0xa20 net/ipv4/inet_timewait_sock.c:267
 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>