rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 	0-...!: (2 ticks this GP) idle=a44c/1/0x4000000000000000 softirq=24895/24895 fqs=0
rcu: 	(detected by 1, t=10505 jiffies, g=21377, q=636 ncpus=2)
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 8407 Comm: syz.3.651 Not tainted 6.13.0-rc3-syzkaller-00154-g30b981796b94 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024
RIP: 0010:__lock_acquire+0xcbf/0x2100 kernel/locking/lockdep.c:5199
Code: bf 00 00 00 00 00 fc ff df 48 0f a3 1d ea 86 af 12 0f 83 66 09 00 00 49 8d 9d d0 0a 00 00 48 89 d8 48 c1 e8 03 48 89 44 24 58 <80> 3c 38 00 74 12 48 89 df e8 f3 11 8b 00 48 bf 00 00 00 00 00 fc
RSP: 0018:ffffc90000007930 EFLAGS: 00000802
RAX: 1ffff110092bf8da RBX: ffff8880495fc6d0 RCX: ffffffff817ac184
RDX: 0000000000000000 RSI: 0000000000000008 RDI: dffffc0000000000
RBP: ffff8880495fc758 R08: ffffffff942a4887 R09: 1ffffffff2854910
R10: dffffc0000000000 R11: fffffbfff2854911 R12: ffff8880495fc6c4
R13: ffff8880495fbc00 R14: 0000000000000000 R15: ffff8880495fc778
FS:  00007f54aa0ef6c0(0000) GS:ffff8880b8600000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f54aa0eef98 CR3: 000000007ebce000 CR4: 00000000003526f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <NMI>
 </NMI>
 <IRQ>
 lock_acquire+0x1ed/0x550 kernel/locking/lockdep.c:5849
 __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline]
 _raw_spin_lock_irqsave+0xd5/0x120 kernel/locking/spinlock.c:162
 debug_object_deactivate+0x158/0x390 lib/debugobjects.c:873
 debug_hrtimer_deactivate kernel/time/hrtimer.c:433 [inline]
 debug_deactivate+0x1b/0x220 kernel/time/hrtimer.c:475
 __run_hrtimer kernel/time/hrtimer.c:1707 [inline]
 __hrtimer_run_queues+0x305/0xd30 kernel/time/hrtimer.c:1803
 hrtimer_interrupt+0x403/0xa40 kernel/time/hrtimer.c:1865
 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1038 [inline]
 __sysvec_apic_timer_interrupt+0x110/0x420 arch/x86/kernel/apic/apic.c:1055
 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1049 [inline]
 sysvec_apic_timer_interrupt+0xa1/0xc0 arch/x86/kernel/apic/apic.c:1049
 </IRQ>
 <TASK>
 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702
RIP: 0010:strlen+0x43/0x70 lib/string.c:413
Code: 00 00 00 fc ff df 48 89 fb 49 89 c4 48 89 d8 48 c1 e8 03 42 0f b6 04 38 84 c0 75 12 48 ff c3 49 8d 44 24 01 43 80 7c 26 01 00 <75> dd eb 13 89 d9 80 e1 07 38 c1 7c e5 48 89 df e8 88 ca 41 f6 eb
RSP: 0018:ffffc900032078a8 EFLAGS: 00000206
RAX: 0000000000000013 RBX: ffffffff8d116b74 RCX: 1ffff1100fbb0c9a
RDX: ffffc900141e6000 RSI: 0000000000006f69 RDI: ffffffff8d116b60
RBP: ffff8880610cee58 R08: ffff88805fb6730f R09: 0000000000000000
R10: ffff88805fb67300 R11: ffffed100bf6ce62 R12: 0000000000000012
R13: ffffffff8d116b60 R14: ffffffff8d116b60 R15: dffffc0000000000
 insert_entry fs/proc/proc_sysctl.c:152 [inline]
 insert_header+0xa2b/0x11d0 fs/proc/proc_sysctl.c:252
 __register_sysctl_table+0x12cf/0x1430 fs/proc/proc_sysctl.c:1395
 nf_conntrack_standalone_init_sysctl net/netfilter/nf_conntrack_standalone.c:1090 [inline]
 nf_conntrack_pernet_init+0x848/0x9d0 net/netfilter/nf_conntrack_standalone.c:1138
 ops_init+0x31e/0x590 net/core/net_namespace.c:138
 setup_net+0x287/0x9e0 net/core/net_namespace.c:362
 copy_net_ns+0x33f/0x570 net/core/net_namespace.c:516
 create_new_namespaces+0x425/0x7b0 kernel/nsproxy.c:110
 unshare_nsproxy_namespaces+0x124/0x180 kernel/nsproxy.c:228
 ksys_unshare+0x57d/0xa70 kernel/fork.c:3334
 __do_sys_unshare kernel/fork.c:3405 [inline]
 __se_sys_unshare kernel/fork.c:3403 [inline]
 __x64_sys_unshare+0x38/0x40 kernel/fork.c:3403
 do_syscall_x64 arch/x86/entry/common.c:52 [inline]
 do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f54a9385d29
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 a8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007f54aa0ef038 EFLAGS: 00000246 ORIG_RAX: 0000000000000110
RAX: ffffffffffffffda RBX: 00007f54a9576400 RCX: 00007f54a9385d29
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000062040200
RBP: 00007f54a9401aa8 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 0000000000000000 R14: 00007f54a9576400 R15: 00007fffcbb67eb8
 </TASK>
rcu: rcu_preempt kthread timer wakeup didn't happen for 10504 jiffies! g21377 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x402
rcu: 	Possible timer handling issue on cpu=0 timer-softirq=8694
rcu: rcu_preempt kthread starved for 10505 jiffies! g21377 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:26264 pid:17    tgid:17    ppid:2      flags:0x00004000
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5369 [inline]
 __schedule+0x1850/0x4c30 kernel/sched/core.c:6756
 __schedule_loop kernel/sched/core.c:6833 [inline]
 schedule+0x14b/0x320 kernel/sched/core.c:6848
 schedule_timeout+0x15a/0x290 kernel/time/sleep_timeout.c:99
 rcu_gp_fqs_loop+0x2df/0x1330 kernel/rcu/tree.c:2045
 rcu_gp_kthread+0xa7/0x3b0 kernel/rcu/tree.c:2247
 kthread+0x2f0/0x390 kernel/kthread.c:389
 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:147
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
 </TASK>