rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 	Tasks blocked on level-0 rcu_node (CPUs 0-1): P5262/1:b..l
rcu: 	(detected by 1, t=10504 jiffies, g=109417, q=63 ncpus=2)
task:kworker/u4:8    state:R  running task     stack:20248 pid:5262  ppid:2      flags:0x00004000
Workqueue: netns cleanup_net
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5343 [inline]
 __schedule+0x187b/0x4900 kernel/sched/core.c:6669
 preempt_schedule_irq+0xfb/0x1b0 kernel/sched/core.c:6981
 irqentry_exit+0x57/0x80 kernel/entry/common.c:433
 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:645
RIP: 0010:inet_twsk_purge+0x1bc/0xad0 net/ipv4/inet_timewait_sock.c:294
Code: 07 03 00 00 48 c7 c2 c0 fc dd 8b e8 3e 60 43 f8 4c 89 e0 48 c1 e8 03 42 80 3c 28 00 74 08 4c 89 e7 e8 68 56 bb f8 4d 8b 3c 24 <4c> 89 fe 48 83 e6 01 31 ff e8 d6 75 63 f8 4c 89 f8 48 83 e0 01 0f
RSP: 0018:ffffc90005affa60 EFLAGS: 00000246
RAX: 1ffff110296f1ed0 RBX: 0000000000000001 RCX: ffff88807c4dbb80
RDX: 0000000000000000 RSI: ffffffff8b384840 RDI: ffffffff8b384800
RBP: ffffc90005affb70 R08: ffffffff892813c8 R09: fffffbfff206584d
R10: 0000000000000000 R11: dffffc0000000001 R12: ffff88814b78f680
R13: dffffc0000000000 R14: ffffffff91f82240 R15: 00000000000e3da1
 ops_exit_list net/core/net_namespace.c:175 [inline]
 cleanup_net+0x767/0xb80 net/core/net_namespace.c:614
 process_one_work+0x8a0/0x10e0 kernel/workqueue.c:2408
 worker_thread+0xa63/0x1210 kernel/workqueue.c:2555
 kthread+0x2b8/0x350 kernel/kthread.c:379
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:308
 </TASK>
rcu: rcu_preempt kthread starved for 10495 jiffies! g109417 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x0 ->cpu=1
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:24856 pid:16    ppid:2      flags:0x00004000
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5343 [inline]
 __schedule+0x187b/0x4900 kernel/sched/core.c:6669
 schedule+0xc3/0x180 kernel/sched/core.c:6745
 schedule_timeout+0x1bd/0x310 kernel/time/timer.c:2167
 rcu_gp_fqs_loop+0x2c6/0x1010 kernel/rcu/tree.c:1609
 rcu_gp_kthread+0xa7/0x3b0 kernel/rcu/tree.c:1808
 kthread+0x2b8/0x350 kernel/kthread.c:379
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:308
 </TASK>
rcu: Stack dump where RCU GP kthread last ran:
CPU: 1 PID: 24764 Comm: kworker/u4:5 Not tainted 6.4.0-syzkaller-00082-gc0a572d9d32f #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/27/2023
Workqueue: events_unbound toggle_allocation_gate
RIP: 0010:csd_lock_wait kernel/smp.c:285 [inline]
RIP: 0010:smp_call_function_many_cond+0x14fb/0x1f60 kernel/smp.c:828
Code: 45 8b 34 24 44 89 f6 83 e6 01 31 ff e8 0e 15 0b 00 41 83 e6 01 49 be 00 00 00 00 00 fc ff df 75 07 e8 49 11 0b 00 eb 38 f3 90 <42> 0f b6 04 33 84 c0 75 11 41 f7 04 24 01 00 00 00 74 1e e8 2d 11
RSP: 0018:ffffc9000349f7c0 EFLAGS: 00000293
RAX: ffffffff818074c3 RBX: 1ffff1101730897d RCX: ffff88803e31d940
RDX: 0000000000000000 RSI: 0000000000000001 RDI: 0000000000000000
RBP: ffffc9000349f9c0 R08: ffffffff81807492 R09: fffffbfff206584d
R10: 0000000000000000 R11: dffffc0000000001 R12: ffff8880b9844be8
R13: ffff8880b993d0c8 R14: dffffc0000000000 R15: 0000000000000000
FS:  0000000000000000(0000) GS:ffff8880b9900000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f507d993718 CR3: 000000000cd30000 CR4: 00000000003526e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <IRQ>
 </IRQ>
 <TASK>
 on_each_cpu_cond_mask+0x3f/0x80 kernel/smp.c:996
 on_each_cpu include/linux/smp.h:71 [inline]
 text_poke_sync arch/x86/kernel/alternative.c:1770 [inline]
 text_poke_bp_batch+0x2bf/0x950 arch/x86/kernel/alternative.c:1970
 text_poke_flush arch/x86/kernel/alternative.c:2161 [inline]
 text_poke_finish+0x1a/0x30 arch/x86/kernel/alternative.c:2168
 arch_jump_label_transform_apply+0x17/0x30 arch/x86/kernel/jump_label.c:146
 static_key_enable_cpuslocked+0x132/0x250 kernel/jump_label.c:205
 static_key_enable+0x1a/0x20 kernel/jump_label.c:218
 toggle_allocation_gate+0xb5/0x250 mm/kfence/core.c:831
 process_one_work+0x8a0/0x10e0 kernel/workqueue.c:2408
 worker_thread+0xa63/0x1210 kernel/workqueue.c:2555
 kthread+0x2b8/0x350 kernel/kthread.c:379
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:308
 </TASK>