rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 	0-...!: (0 ticks this GP) idle=ea3c/1/0x4000000000000000 softirq=87352/87352 fqs=0
rcu: 	(detected by 1, t=10502 jiffies, g=69229, q=387 ncpus=2)
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 1115 Comm: kworker/u8:6 Not tainted 6.15.0-syzkaller-03589-gfeacb1774bd5 #0 PREEMPT(full) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025
Workqueue: netns cleanup_net
RIP: 0010:debug_objects_fill_pool+0x11/0x500 lib/debugobjects.c:698
Code: 8b 4c 24 10 e9 09 fe ff ff 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 48 b8 00 00 00 00 00 fc ff df 41 56 41 55 41 54 55 <53> 48 83 ec 68 48 c7 44 24 08 b3 8a b5 41 48 8d 5c 24 08 48 c7 44
RSP: 0018:ffffc90000007cf8 EFLAGS: 00000002
RAX: dffffc0000000000 RBX: ffff8880b8427d40 RCX: ffffffff81a84916
RDX: ffff8880282f4880 RSI: ffffffff8b8fee80 RDI: ffff888033d70340
RBP: ffffc90000007e08 R08: 0000000000000001 R09: ffffc90000007d40
R10: 0000000000000000 R11: 0000000000000001 R12: dffffc0000000000
R13: ffff888033d70340 R14: ffff888033d70340 R15: 1ffff92000000fa8
FS:  0000000000000000(0000) GS:ffff88812499f000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000200000009038 CR3: 0000000027126000 CR4: 00000000003526f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <IRQ>
 debug_object_activate+0x10b/0x4c0 lib/debugobjects.c:814
 debug_hrtimer_activate kernel/time/hrtimer.c:445 [inline]
 debug_activate kernel/time/hrtimer.c:484 [inline]
 enqueue_hrtimer+0x23/0x3b0 kernel/time/hrtimer.c:1088
 __run_hrtimer kernel/time/hrtimer.c:1778 [inline]
 __hrtimer_run_queues+0x8ff/0xad0 kernel/time/hrtimer.c:1825
 hrtimer_interrupt+0x397/0x8e0 kernel/time/hrtimer.c:1887
 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1039 [inline]
 __sysvec_apic_timer_interrupt+0x108/0x3f0 arch/x86/kernel/apic/apic.c:1056
 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1050 [inline]
 sysvec_apic_timer_interrupt+0x9f/0xc0 arch/x86/kernel/apic/apic.c:1050
 </IRQ>
 <TASK>
 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702
RIP: 0010:get_current arch/x86/include/asm/current.h:25 [inline]
RIP: 0010:__sanitizer_cov_trace_pc+0x8/0x70 kernel/kcov.c:216
Code: e9 8d 55 5b 00 be 03 00 00 00 5b e9 92 84 1b 03 66 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 f3 0f 1e fa 48 8b 34 24 <65> 48 8b 15 98 9b ec 11 65 8b 05 a9 9b ec 11 a9 00 01 ff 00 74 1d
RSP: 0018:ffffc900039d7620 EFLAGS: 00000202
RAX: 0000000000000000 RBX: 0000000000000002 RCX: ffffffff82606e99
RDX: ffff8880282f4880 RSI: ffffffff82606ce2 RDI: 0000000000000003
RBP: ffff8880325d6780 R08: 0000000000000003 R09: 0000000000000001
R10: 0000000000000002 R11: 0000000000000001 R12: 0000000000000001
R13: ffff8880325d6780 R14: dffffc0000000000 R15: ffff888144ac80a0
 kernfs_parent fs/kernfs/kernfs-internal.h:125 [inline]
 kernfs_next_descendant_post+0x1a2/0x420 fs/kernfs/dir.c:1387
 __kernfs_remove+0x118/0x890 fs/kernfs/dir.c:1488
 kernfs_remove_by_name_ns+0x68/0x110 fs/kernfs/dir.c:1714
 kernfs_remove_by_name include/linux/kernfs.h:633 [inline]
 remove_files+0x96/0x1c0 fs/sysfs/group.c:28
 sysfs_remove_group+0x8b/0x180 fs/sysfs/group.c:322
 sysfs_remove_groups fs/sysfs/group.c:346 [inline]
 sysfs_remove_groups+0x60/0xa0 fs/sysfs/group.c:338
 device_remove_groups drivers/base/core.c:2846 [inline]
 device_remove_attrs+0x192/0x290 drivers/base/core.c:2976
 device_del+0x38e/0x9f0 drivers/base/core.c:3880
 unregister_netdevice_many_notify+0x1904/0x26f0 net/core/dev.c:12008
 unregister_netdevice_many net/core/dev.c:12036 [inline]
 default_device_exit_batch+0x853/0xaf0 net/core/dev.c:12530
 ops_exit_list+0x128/0x180 net/core/net_namespace.c:177
 cleanup_net+0x5c1/0xb30 net/core/net_namespace.c:654
 process_one_work+0x9cf/0x1b70 kernel/workqueue.c:3238
 process_scheduled_works kernel/workqueue.c:3321 [inline]
 worker_thread+0x6c8/0xf10 kernel/workqueue.c:3402
 kthread+0x3c5/0x780 kernel/kthread.c:464
 ret_from_fork+0x5d4/0x6f0 arch/x86/kernel/process.c:148
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
 </TASK>
rcu: rcu_preempt kthread timer wakeup didn't happen for 10501 jiffies! g69229 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x402
rcu: 	Possible timer handling issue on cpu=0 timer-softirq=29443
rcu: rcu_preempt kthread starved for 10502 jiffies! g69229 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:27688 pid:16    tgid:16    ppid:2      task_flags:0x208040 flags:0x00004000
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5392 [inline]
 __schedule+0x116a/0x5de0 kernel/sched/core.c:6781
 __schedule_loop kernel/sched/core.c:6859 [inline]
 schedule+0xe7/0x3a0 kernel/sched/core.c:6874
 schedule_timeout+0x123/0x290 kernel/time/sleep_timeout.c:99
 rcu_gp_fqs_loop+0x1ea/0xb00 kernel/rcu/tree.c:2054
 rcu_gp_kthread+0x270/0x380 kernel/rcu/tree.c:2256
 kthread+0x3c5/0x780 kernel/kthread.c:464
 ret_from_fork+0x5d4/0x6f0 arch/x86/kernel/process.c:148
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
 </TASK>