rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 	0-...!: (3 ticks this GP) idle=677/1/0x4000000000000002 softirq=13085/13085 fqs=59 
	(detected by 1, t=10502 jiffies, g=15441, q=618)
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 PID: 4174 Comm: kworker/0:3 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/24/2026
Workqueue: events_power_efficient neigh_periodic_work
RIP: 0010:unwind_next_frame+0x104b/0x1cf0 arch/x86/kernel/unwind_orc.c:592
Code: 49 83 c4 03 4c 89 f8 48 c1 e8 03 0f b6 04 28 84 c0 0f 85 16 0b 00 00 4c 89 e0 48 c1 e8 03 0f b6 04 28 84 c0 0f 85 27 0b 00 00 <49> 0f bf 07 49 01 c0 48 8d 53 40 48 89 df 4c 89 c6 eb 58 4c 8d 73
RSP: 0018:ffffc900010deff8 EFLAGS: 00000046
RAX: 0000000000000000 RBX: ffffc900010df140 RCX: 0000000000000000
RDX: 0000000000000010 RSI: 0000000000000001 RDI: ffffc900010df1a0
RBP: dffffc0000000000 R08: ffffc900010df528 R09: ffffc900010df190
R10: dffffc0000000000 R11: fffff5200021be34 R12: ffffffff8e0cd011
R13: 1ffffffff1c19a02 R14: ffffc900010df175 R15: ffffffff8e0cd010
FS:  0000000000000000(0000) GS:ffff8880b9000000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000000c000000000 CR3: 0000000062911000 CR4: 00000000003506f0
DR0: 0000000000000000 DR1: 0000200000000300 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000600
Call Trace:
 <TASK>
 __unwind_start+0x51a/0x650 arch/x86/kernel/unwind_orc.c:704
 unwind_start arch/x86/include/asm/unwind.h:60 [inline]
 perf_callchain_kernel+0x2f4/0x760 arch/x86/events/core.c:2780
 get_perf_callchain+0x356/0x460 kernel/events/callchain.c:200
 perf_callchain kernel/events/core.c:7616 [inline]
 perf_prepare_sample+0x352/0x1cb0 kernel/events/core.c:7643
 __perf_event_output kernel/events/core.c:7812 [inline]
 perf_event_output_forward+0x185/0x2e0 kernel/events/core.c:7832
 __perf_event_overflow+0x35f/0x550 kernel/events/core.c:9525
 perf_tp_event+0x324/0xbe0 kernel/events/core.c:10057
 perf_trace_run_bpf_submit+0xf3/0x1c0 kernel/events/core.c:10031
 perf_trace_preemptirq_template+0x2aa/0x360 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+0x7f/0x4a0 kernel/rcu/tree_plugin.h:674
Code: eb 03 48 b8 f1 f1 f1 f1 f8 f2 f2 f2 4a 89 04 2b 42 c7 44 2b 08 f8 f3 f3 f3 65 44 8b 35 42 0b 9d 7e 41 f7 c6 00 00 f0 00 74 40 <48> c7 44 24 20 0e 36 e0 45 4a c7 04 2b 00 00 00 00 42 c7 44 2b 08
RSP: 0018:ffffc900010dfa40 EFLAGS: 00000206
RAX: 197b3afdf6642300 RBX: 1ffff9200021bf4c RCX: 197b3afdf6642300
RDX: dffffc0000000000 RSI: ffffffff8a2b2be0 RDI: ffffffff8a7a48c0
RBP: ffffc900010dfb08 R08: ffffffff901f10ff R09: 1ffffffff203e21f
R10: dffffc0000000000 R11: fffffbfff203e220 R12: ffffffff8c323400
R13: dffffc0000000000 R14: 0000000000000246 R15: 0000000000000001
 __rcu_read_unlock+0x78/0xd0 kernel/rcu/tree_plugin.h:422
 rcu_read_unlock include/linux/rcupdate.h:772 [inline]
 atomic_notifier_call_chain+0x254/0x280 kernel/notifier.c:199
 neigh_cleanup_and_release+0xaa/0x250 net/core/neighbour.c:102
 neigh_periodic_work+0x406/0xc70 net/core/neighbour.c:947
 process_one_work+0x867/0xff0 kernel/workqueue.c:2310
 worker_thread+0xad7/0x12a0 kernel/workqueue.c:2457
 kthread+0x42e/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 10383 jiffies! g15441 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x402
rcu: 	Possible timer handling issue on cpu=1 timer-softirq=10961
rcu: rcu_preempt kthread starved for 10384 jiffies! g15441 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x402 ->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:I stack:27856 pid:   15 ppid:     2 flags:0x00004000
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5049 [inline]
 __schedule+0x11c3/0x4350 kernel/sched/core.c:6395
 schedule+0x11b/0x1e0 kernel/sched/core.c:6478
 schedule_timeout+0x184/0x2d0 kernel/time/timer.c:2117
 rcu_gp_fqs_loop+0x2be/0x11f0 kernel/rcu/tree.c:1972
 rcu_gp_kthread+0x9a/0x370 kernel/rcu/tree.c:2145
 kthread+0x42e/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:
NMI backtrace for cpu 1
CPU: 1 PID: 6074 Comm: syz.4.544 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/24/2026
Call Trace:
 <IRQ>
 dump_stack_lvl+0x188/0x250 lib/dump_stack.c:106
 nmi_cpu_backtrace+0x3a2/0x3d0 lib/nmi_backtrace.c:111
 nmi_trigger_cpumask_backtrace+0x163/0x280 lib/nmi_backtrace.c:62
 trigger_single_cpu_backtrace include/linux/nmi.h:166 [inline]
 rcu_check_gp_kthread_starvation+0x1cd/0x250 kernel/rcu/tree_stall.h:487
 print_other_cpu_stall+0x1110/0x1270 kernel/rcu/tree_stall.h:592
 check_cpu_stall kernel/rcu/tree_stall.h:745 [inline]
 rcu_pending kernel/rcu/tree.c:3936 [inline]
 rcu_sched_clock_irq+0x845/0x1120 kernel/rcu/tree.c:2619
 update_process_times+0x193/0x200 kernel/time/timer.c:2021
 tick_sched_handle kernel/time/tick-sched.c:254 [inline]
 tick_sched_timer+0x37d/0x560 kernel/time/tick-sched.c:1473
 __run_hrtimer kernel/time/hrtimer.c:1685 [inline]
 __hrtimer_run_queues+0x4b0/0xb60 kernel/time/hrtimer.c:1749
 hrtimer_interrupt+0x397/0x8b0 kernel/time/hrtimer.c:1811
 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1097 [inline]
 __sysvec_apic_timer_interrupt+0x137/0x4a0 arch/x86/kernel/apic/apic.c:1114
 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1108 [inline]
 sysvec_apic_timer_interrupt+0x4d/0xc0 arch/x86/kernel/apic/apic.c:1108
 asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:676
RIP: 0010:queued_write_lock_slowpath+0x129/0x270 kernel/locking/qrwlock.c:78
Code: f0 41 81 0e 00 01 00 00 43 0f b6 04 27 84 c0 74 37 44 89 f1 80 e1 07 80 c1 03 38 c1 7c 2a 4c 89 f7 e8 cb f6 5f 00 eb 20 f3 90 <43> 0f b6 04 27 84 c0 74 15 44 89 f1 80 e1 07 80 c1 03 38 c1 7c 08
RSP: 0018:ffffc90000dd04e0 EFLAGS: 00000206
RAX: 00000000000001ff RBX: ffffc90000dd0530 RCX: ffffffff815e515f
RDX: 0000000000000001 RSI: 0000000000000004 RDI: ffffffff8d54c958
RBP: ffffc90000dd0590 R08: ffffffff8d54c95b R09: 1ffffffff1aa992b
R10: dffffc0000000000 R11: fffffbfff1aa992c R12: dffffc0000000000
R13: 1ffff920001ba0a0 R14: ffffffff8d54c958 R15: 1ffffffff1aa992b
 queued_write_lock include/asm-generic/qrwlock.h:97 [inline]
 do_raw_write_lock+0x1e6/0x260 kernel/locking/spinlock_debug.c:210
 ___neigh_create+0xdf3/0x2210 net/core/neighbour.c:625
 ip6_finish_output2+0xacc/0x1640 net/ipv6/ip6_output.c:129
 dst_output include/net/dst.h:452 [inline]
 NF_HOOK include/linux/netfilter.h:302 [inline]
 ndisc_send_skb+0xb7c/0x1410 net/ipv6/ndisc.c:513
 addrconf_rs_timer+0x367/0x640 net/ipv6/addrconf.c:3966
 call_timer_fn+0x17b/0x540 kernel/time/timer.c:1648
 expire_timers kernel/time/timer.c:1699 [inline]
 __run_timers+0x56c/0x810 kernel/time/timer.c:1970
 run_timer_softirq+0x63/0xf0 kernel/time/timer.c:1983
 handle_softirqs+0x336/0x830 kernel/softirq.c:576
 __do_softirq kernel/softirq.c:610 [inline]
 invoke_softirq kernel/softirq.c:450 [inline]
 __irq_exit_rcu+0x13b/0x230 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:__kasan_check_read+0x0/0x10 mm/kasan/shadow.c:31
Code: 41 5c 41 5d 41 5e 41 5f 5d c3 48 c7 c7 2b bf df 8b eb 0a 48 c7 c7 2f b1 c5 8b 48 89 de e8 48 48 f8 07 31 ed eb d7 00 00 cc cc <89> f6 48 8b 0c 24 31 d2 e9 43 ef ff ff 0f 1f 00 89 f6 48 8b 0c 24
RSP: 0018:ffffc9000313f658 EFLAGS: 00000287
RAX: ffffffff81a2e577 RBX: ffffea0001cd8ff4 RCX: ffff88802703d940
RDX: 0000000000000000 RSI: 0000000000000004 RDI: ffffea0001cd8ff4
RBP: ffffc9000313f768 R08: ffffea0001cd8fb7 R09: 1ffffd400039b1f6
R10: dffffc0000000000 R11: fffff9400039b1f7 R12: dffffc0000000000
R13: 0000000000000000 R14: ffffea0001cd8fc0 R15: 0200000000000000
 instrument_atomic_read include/linux/instrumented.h:71 [inline]
 atomic_read include/linux/atomic/atomic-instrumented.h:27 [inline]
 page_ref_count include/linux/page_ref.h:67 [inline]
 put_page_testzero include/linux/mm.h:758 [inline]
 release_pages+0x27e/0x1bd0 mm/swap.c:931
 tlb_batch_pages_flush mm/mmu_gather.c:50 [inline]
 tlb_flush_mmu_free mm/mmu_gather.c:241 [inline]
 tlb_flush_mmu mm/mmu_gather.c:248 [inline]
 tlb_finish_mmu+0x1b4/0x370 mm/mmu_gather.c:371
 exit_mmap+0x3d0/0x640 mm/mmap.c:3218
 __mmput+0x115/0x390 kernel/fork.c:1133
 exit_mm+0x632/0x7b0 kernel/exit.c:557
 do_exit+0x5b8/0x2110 kernel/exit.c:877
 do_group_exit+0x12c/0x2f0 kernel/exit.c:1004
 get_signal+0x7eb/0x12e0 kernel/signal.c:2913
 arch_do_signal_or_restart+0xe6/0x12a0 arch/x86/kernel/signal.c:867
 handle_signal_work kernel/entry/common.c:157 [inline]
 exit_to_user_mode_loop+0x9e/0x130 kernel/entry/common.c:181
 exit_to_user_mode_prepare+0xee/0x180 kernel/entry/common.c:217
 irqentry_exit_to_user_mode+0x5/0x30 kernel/entry/common.c:323
 exc_page_fault+0x88/0x100 arch/x86/mm/fault.c:1499
 asm_exc_page_fault+0x22/0x30 arch/x86/include/asm/idtentry.h:606
RIP: 0033:0x7fabfec74bd7
Code: Unable to access opcode bytes at RIP 0x7fabfec74bad.
RSP: 002b:00007fabfcff8120 EFLAGS: 00010202
RAX: 0000000000000000 RBX: 000000000000000b RCX: 00007fabfedbf159
RDX: 00007fabfcff8140 RSI: 00007fabfcff8270 RDI: 000000000000000b
RBP: 00007fabfee5606b R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000206 R12: 0000000000000000
R13: 00007fabff047038 R14: 00007fabff046fa0 R15: 00007ffc7859a0f8
 </TASK>