rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 	0-...!: (1 ticks this GP) idle=eab/1/0x4000000000000002 softirq=28641/28641 fqs=0 
	(detected by 1, t=10502 jiffies, g=44337, q=771)
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 PID: 5333 Comm: kworker/u4:19 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025
Workqueue: netns cleanup_net
RIP: 0010:__lock_acquire+0x4c6/0x7c60 kernel/locking/lockdep.c:4955
Code: 68 83 e0 01 c1 e0 12 09 c8 8b 8c 24 c8 00 00 00 c1 e1 13 41 c1 e5 14 41 09 cd 45 09 f5 41 09 c5 48 8b 44 24 58 42 0f b6 04 00 <84> c0 0f 85 13 62 00 00 44 8b 75 28 45 89 6f 20 49 8d 5f 24 48 89
RSP: 0018:ffffc900000071e0 EFLAGS: 00000002
RAX: 0000000000000000 RBX: 0000000000002000 RCX: 0000000000080000
RDX: 0000000000000015 RSI: 0000000000000000 RDI: ffff888059d1a9d8
RBP: ffffc90000007430 R08: dffffc0000000000 R09: 0000000000000001
R10: fffffbfff1ad3196 R11: 1ffffffff1ad3195 R12: ffff888059d1a894
R13: 00000000000a2015 R14: 0000000000000015 R15: ffff888059d1a9c8
FS:  0000000000000000(0000) GS:ffff8880b9000000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000000000000 CR3: 000000000be8e000 CR4: 00000000003506f0
DR0: 0000000000000000 DR1: 0000200000000300 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000600
Call Trace:
 <IRQ>
 lock_acquire+0x197/0x3f0 kernel/locking/lockdep.c:5623
 rcu_lock_acquire+0x2a/0x30 include/linux/rcupdate.h:312
 rcu_read_lock include/linux/rcupdate.h:739 [inline]
 __perf_event_output kernel/events/core.c:7800 [inline]
 perf_event_output_forward+0x9e/0x280 kernel/events/core.c:7822
 __perf_event_overflow+0x364/0x530 kernel/events/core.c:9515
 perf_swevent_overflow kernel/events/core.c:9591 [inline]
 perf_swevent_event+0x4ad/0x530 kernel/events/core.c:9629
 perf_tp_event+0x32c/0xb50 kernel/events/core.c:10047
 perf_trace_run_bpf_submit+0xf3/0x1c0 kernel/events/core.c:10021
 perf_trace_preemptirq_template+0x2be/0x380 include/trace/events/preemptirq.h:14
 trace_irq_enable_rcuidle+0x108/0x180 include/trace/events/preemptirq.h:40
 trace_hardirqs_on+0x57/0x80 kernel/trace/trace_preemptirq.c:44
 asm_sysvec_irq_work+0x16/0x20 arch/x86/include/asm/idtentry.h:713
RIP: 0010:rcu_read_unlock_special+0x84/0x480 kernel/rcu/tree_plugin.h:674
Code: f1 f1 f1 00 f2 f2 f2 4a 89 04 2b 66 42 c7 44 2b 09 f3 f3 42 c6 44 2b 0b f3 65 44 8b 35 dd 13 9e 7e 41 f7 c6 00 00 f0 00 74 45 <48> c7 44 24 20 0e 36 e0 45 4a c7 04 2b 00 00 00 00 66 42 c7 44 2b
RSP: 0018:ffffc90000007c60 EFLAGS: 00000206
RAX: 31f3bdb334894600 RBX: 1ffff92000000f90 RCX: 31f3bdb334894600
RDX: dffffc0000000000 RSI: ffffffff8a0b1620 RDI: ffffffff8a59a240
RBP: ffffc90000007d28 R08: dffffc0000000000 R09: fffffbfff1ff761d
R10: fffffbfff1ff761d R11: 1ffffffff1ff761c R12: ffffffff8c120900
R13: dffffc0000000000 R14: 0000000000000246 R15: 0000000000000001
 __rcu_read_unlock+0x78/0xd0 kernel/rcu/tree_plugin.h:422
 rcu_read_unlock include/linux/rcupdate.h:771 [inline]
 rebalance_domains+0xa51/0xb80 kernel/sched/fair.c:10660
 handle_softirqs+0x328/0x820 kernel/softirq.c:576
 __do_softirq kernel/softirq.c:610 [inline]
 invoke_softirq kernel/softirq.c:450 [inline]
 __irq_exit_rcu+0x12f/0x220 kernel/softirq.c:659
 irq_exit_rcu+0x5/0x20 kernel/softirq.c:671
 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1108 [inline]
 sysvec_apic_timer_interrupt+0xa0/0xc0 arch/x86/kernel/apic/apic.c:1108
 </IRQ>
 <TASK>
 asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:676
RIP: 0010:memset+0x2b/0x40 mm/kasan/shadow.c:47
Code: 41 56 53 48 89 d3 89 f5 49 89 fe 48 8b 4c 24 18 48 89 d6 ba 01 00 00 00 e8 12 ef ff ff 84 c0 74 11 4c 89 f7 89 ee 48 89 da 5b <41> 5e 5d e9 ed d8 44 02 31 c0 5b 41 5e 5d c3 66 0f 1f 44 00 00 41
RSP: 0018:ffffc9000369f328 EFLAGS: 00000202
RAX: 1ffff1100a10ba01 RBX: ffff88805fdc8f30 RCX: ffffffff81c952c2
RDX: 0000000000000050 RSI: 0000000000000000 RDI: ffffc9000369f380
RBP: 0000000000000000 R08: dffffc0000000000 R09: fffff520006d3e7a
R10: fffff520006d3e7a R11: 1ffff920006d3e70 R12: dffffc0000000000
R13: ffff88805085d318 R14: ffffc9000369f380 R15: 1ffff920006d3e6c
 __lookup_slow+0xb2/0x3d0 fs/namei.c:1642
 lookup_one_len+0x18e/0x2c0 fs/namei.c:2718
 start_creating+0x184/0x310 fs/debugfs/inode.c:354
 __debugfs_create_file+0x6f/0x510 fs/debugfs/inode.c:399
 nsim_ethtool_init+0x1fd/0x350 drivers/net/netdevsim/ethtool.c:153
 nsim_create+0x1c9/0x3e0 drivers/net/netdevsim/netdev.c:363
 __nsim_dev_port_add+0x5c7/0x980 drivers/net/netdevsim/dev.c:1312
 nsim_dev_port_add_all+0x37/0x100 drivers/net/netdevsim/dev.c:1372
 nsim_dev_reload_create drivers/net/netdevsim/dev.c:1421 [inline]
 nsim_dev_reload_up+0x48b/0x7f0 drivers/net/netdevsim/dev.c:910
 devlink_reload+0x342/0x770 net/core/devlink.c:3970
 devlink_pernet_pre_exit+0x19d/0x300 net/core/devlink.c:11543
 ops_pre_exit_list net/core/net_namespace.c:162 [inline]
 cleanup_net+0x57b/0xb80 net/core/net_namespace.c:615
 process_one_work+0x863/0x1000 kernel/workqueue.c:2310
 worker_thread+0xaa8/0x12a0 kernel/workqueue.c:2457
 kthread+0x436/0x520 kernel/kthread.c:334
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:287
 </TASK>
rcu: rcu_preempt kthread timer wakeup didn't happen for 10501 jiffies! g44337 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x402
rcu: 	Possible timer handling issue on cpu=0 timer-softirq=21237
rcu: rcu_preempt kthread starved for 10502 jiffies! g44337 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:26624 pid:   15 ppid:     2 flags:0x00004000
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5049 [inline]
 __schedule+0x11bb/0x4390 kernel/sched/core.c:6395
 schedule+0x11b/0x1e0 kernel/sched/core.c:6478
 schedule_timeout+0x15c/0x280 kernel/time/timer.c:1914
 rcu_gp_fqs_loop+0x29e/0x11b0 kernel/rcu/tree.c:1972
 rcu_gp_kthread+0x98/0x350 kernel/rcu/tree.c:2145
 kthread+0x436/0x520 kernel/kthread.c:334
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:287
 </TASK>
rcu: Stack dump where RCU GP kthread last ran:
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 PID: 5333 Comm: kworker/u4:19 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025
Workqueue: netns cleanup_net
RIP: 0010:perf_tp_filter_match kernel/events/core.c:9986 [inline]
RIP: 0010:perf_tp_event_match kernel/events/core.c:10003 [inline]
RIP: 0010:perf_tp_event+0x2fb/0xb50 kernel/events/core.c:10046
Code: 4d 8b bd e0 02 00 00 4d 85 ff 4d 0f 44 fd 49 81 c7 50 05 00 00 4c 89 f8 48 c1 e8 03 48 b9 00 00 00 00 00 fc ff df 80 3c 08 00 <74> 08 4c 89 ff e8 8b 4d 25 00 4d 8b 3f 4d 85 ff 75 6a e8 4e e7 e0
RSP: 0018:ffffc90000007780 EFLAGS: 00000046
RAX: 1ffff11003d0e465 RBX: 1ffff11017206a40 RCX: dffffc0000000000
RDX: 0000000000000100 RSI: 0000000000000000 RDI: ffff88801e8720b8
RBP: ffffc90000007a08 R08: dffffc0000000000 R09: ffffed100b3a33b9
R10: ffffed100b3a33b9 R11: 1ffff1100b3a33b8 R12: ffff8880b9035200
R13: ffff88801e871dd8 R14: 0000000000000000 R15: ffff88801e872328
FS:  0000000000000000(0000) GS:ffff8880b9000000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000000000000 CR3: 000000000be8e000 CR4: 00000000003506f0
DR0: 0000000000000000 DR1: 0000200000000300 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000600
Call Trace:
 <IRQ>
 perf_trace_run_bpf_submit+0xf3/0x1c0 kernel/events/core.c:10021
 perf_trace_preemptirq_template+0x2be/0x380 include/trace/events/preemptirq.h:14
 trace_irq_enable_rcuidle+0x108/0x180 include/trace/events/preemptirq.h:40
 trace_hardirqs_on+0x57/0x80 kernel/trace/trace_preemptirq.c:44
 asm_sysvec_irq_work+0x16/0x20 arch/x86/include/asm/idtentry.h:713
RIP: 0010:rcu_read_unlock_special+0x84/0x480 kernel/rcu/tree_plugin.h:674
Code: f1 f1 f1 00 f2 f2 f2 4a 89 04 2b 66 42 c7 44 2b 09 f3 f3 42 c6 44 2b 0b f3 65 44 8b 35 dd 13 9e 7e 41 f7 c6 00 00 f0 00 74 45 <48> c7 44 24 20 0e 36 e0 45 4a c7 04 2b 00 00 00 00 66 42 c7 44 2b
RSP: 0018:ffffc90000007c60 EFLAGS: 00000206
RAX: 31f3bdb334894600 RBX: 1ffff92000000f90 RCX: 31f3bdb334894600
RDX: dffffc0000000000 RSI: ffffffff8a0b1620 RDI: ffffffff8a59a240
RBP: ffffc90000007d28 R08: dffffc0000000000 R09: fffffbfff1ff761d
R10: fffffbfff1ff761d R11: 1ffffffff1ff761c R12: ffffffff8c120900
R13: dffffc0000000000 R14: 0000000000000246 R15: 0000000000000001
 __rcu_read_unlock+0x78/0xd0 kernel/rcu/tree_plugin.h:422
 rcu_read_unlock include/linux/rcupdate.h:771 [inline]
 rebalance_domains+0xa51/0xb80 kernel/sched/fair.c:10660
 handle_softirqs+0x328/0x820 kernel/softirq.c:576
 __do_softirq kernel/softirq.c:610 [inline]
 invoke_softirq kernel/softirq.c:450 [inline]
 __irq_exit_rcu+0x12f/0x220 kernel/softirq.c:659
 irq_exit_rcu+0x5/0x20 kernel/softirq.c:671
 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1108 [inline]
 sysvec_apic_timer_interrupt+0xa0/0xc0 arch/x86/kernel/apic/apic.c:1108
 </IRQ>
 <TASK>
 asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:676
RIP: 0010:memset+0x2b/0x40 mm/kasan/shadow.c:47
Code: 41 56 53 48 89 d3 89 f5 49 89 fe 48 8b 4c 24 18 48 89 d6 ba 01 00 00 00 e8 12 ef ff ff 84 c0 74 11 4c 89 f7 89 ee 48 89 da 5b <41> 5e 5d e9 ed d8 44 02 31 c0 5b 41 5e 5d c3 66 0f 1f 44 00 00 41
RSP: 0018:ffffc9000369f328 EFLAGS: 00000202
RAX: 1ffff1100a10ba01 RBX: ffff88805fdc8f30 RCX: ffffffff81c952c2
RDX: 0000000000000050 RSI: 0000000000000000 RDI: ffffc9000369f380
RBP: 0000000000000000 R08: dffffc0000000000 R09: fffff520006d3e7a
R10: fffff520006d3e7a R11: 1ffff920006d3e70 R12: dffffc0000000000
R13: ffff88805085d318 R14: ffffc9000369f380 R15: 1ffff920006d3e6c
 __lookup_slow+0xb2/0x3d0 fs/namei.c:1642
 lookup_one_len+0x18e/0x2c0 fs/namei.c:2718
 start_creating+0x184/0x310 fs/debugfs/inode.c:354
 __debugfs_create_file+0x6f/0x510 fs/debugfs/inode.c:399
 nsim_ethtool_init+0x1fd/0x350 drivers/net/netdevsim/ethtool.c:153
 nsim_create+0x1c9/0x3e0 drivers/net/netdevsim/netdev.c:363
 __nsim_dev_port_add+0x5c7/0x980 drivers/net/netdevsim/dev.c:1312
 nsim_dev_port_add_all+0x37/0x100 drivers/net/netdevsim/dev.c:1372
 nsim_dev_reload_create drivers/net/netdevsim/dev.c:1421 [inline]
 nsim_dev_reload_up+0x48b/0x7f0 drivers/net/netdevsim/dev.c:910
 devlink_reload+0x342/0x770 net/core/devlink.c:3970
 devlink_pernet_pre_exit+0x19d/0x300 net/core/devlink.c:11543
 ops_pre_exit_list net/core/net_namespace.c:162 [inline]
 cleanup_net+0x57b/0xb80 net/core/net_namespace.c:615
 process_one_work+0x863/0x1000 kernel/workqueue.c:2310
 worker_thread+0xaa8/0x12a0 kernel/workqueue.c:2457
 kthread+0x436/0x520 kernel/kthread.c:334
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:287
 </TASK>