rcu: INFO: rcu_preempt self-detected stall on CPU
rcu: 	0-...!: (1 GPs behind) idle=46f/1/0x4000000000000000 softirq=9012/9013 fqs=1848 
	(t=10501 jiffies g=10509 q=951)
rcu: rcu_preempt kthread timer wakeup didn't happen for 6800 jiffies! g10509 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x402
rcu: 	Possible timer handling issue on cpu=1 timer-softirq=7687
rcu: rcu_preempt kthread starved for 6803 jiffies! g10509 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:27880 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 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 PID: 0 Comm: swapper/1 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025
RIP: 0010:native_safe_halt arch/x86/include/asm/irqflags.h:51 [inline]
RIP: 0010:arch_safe_halt arch/x86/include/asm/irqflags.h:89 [inline]
RIP: 0010:kvm_wait+0x141/0x190 arch/x86/kernel/kvm.c:918
Code: 89 df 48 89 f8 48 c1 e8 03 42 0f b6 04 30 84 c0 75 47 0f b6 1f e8 1f e2 49 00 44 38 e3 75 10 66 90 0f 00 2d c1 68 d4 08 fb f4 <e9> 33 ff ff ff fb e9 2d ff ff ff e8 4f df 6d 08 89 f9 80 e1 07 38
RSP: 0018:ffffc90000dd0200 EFLAGS: 00000246
RAX: b3d1f20807472d00 RBX: 0000000000000003 RCX: b3d1f20807472d00
RDX: dffffc0000000000 RSI: ffffffff8a0b1be0 RDI: ffffffff8a59e800
RBP: ffffc90000dd02b0 R08: dffffc0000000000 R09: fffffbfff1ff5438
R10: fffffbfff1ff5438 R11: 1ffffffff1ff5437 R12: 0000000000000003
R13: ffff8880b913b154 R14: dffffc0000000000 R15: 1ffff920001ba040
FS:  0000000000000000(0000) GS:ffff8880b9100000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000055d8a0b51ed8 CR3: 000000001eb86000 CR4: 00000000003506e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000600
Call Trace:
 <IRQ>
 pv_wait arch/x86/include/asm/paravirt.h:597 [inline]
 pv_wait_head_or_lock kernel/locking/qspinlock_paravirt.h:470 [inline]
 __pv_queued_spin_lock_slowpath+0x60f/0x9c0 kernel/locking/qspinlock.c:508
 pv_queued_spin_lock_slowpath arch/x86/include/asm/paravirt.h:585 [inline]
 queued_spin_lock_slowpath+0x43/0x50 arch/x86/include/asm/qspinlock.h:51
 queued_spin_lock include/asm-generic/qspinlock.h:85 [inline]
 do_raw_spin_lock+0x217/0x280 kernel/locking/spinlock_debug.c:115
 spin_lock_bh include/linux/spinlock.h:369 [inline]
 hsr_dev_xmit+0x1b7/0x2e0 net/hsr/hsr_device.c:240
 __netdev_start_xmit include/linux/netdevice.h:5036 [inline]
 netdev_start_xmit include/linux/netdevice.h:5050 [inline]
 xmit_one net/core/dev.c:3649 [inline]
 dev_hard_start_xmit+0x2a5/0x7e0 net/core/dev.c:3665
 __dev_queue_xmit+0x19df/0x2ed0 net/core/dev.c:4288
 neigh_output include/net/neighbour.h:509 [inline]
 ip6_finish_output2+0x1070/0x1500 net/ipv6/ip6_output.c:130
 dst_output include/net/dst.h:452 [inline]
 NF_HOOK include/linux/netfilter.h:302 [inline]
 ndisc_send_skb+0xbea/0x14a0 net/ipv6/ndisc.c:513
 addrconf_rs_timer+0x2b8/0x600 net/ipv6/addrconf.c:3956
 call_timer_fn+0x16c/0x530 kernel/time/timer.c:1451
 expire_timers kernel/time/timer.c:1496 [inline]
 __run_timers+0x525/0x7c0 kernel/time/timer.c:1767
 run_timer_softirq+0x63/0xf0 kernel/time/timer.c:1780
 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:default_idle+0xb/0x10 arch/x86/kernel/process.c:730
Code: bf 48 89 df e8 c6 03 11 f8 eb b5 e8 ef b5 f6 ff 00 00 cc cc 00 00 cc cc 00 00 cc cc 00 00 cc 66 90 0f 00 2d 17 93 5a 00 fb f4 <c3> 0f 1f 40 00 41 57 41 56 53 49 be 00 00 00 00 00 fc ff df 65 48
RSP: 0018:ffffc90000d67d48 EFLAGS: 000002c2
RAX: b3d1f20807472d00 RBX: ffff88813fe48000 RCX: b3d1f20807472d00
RDX: 0000000000000001 RSI: ffffffff8a0b1be0 RDI: ffffffff8a59e800
RBP: ffffc90000d67e80 R08: dffffc0000000000 R09: ffffed1017227662
R10: ffffed1017227662 R11: 1ffff11017227661 R12: ffffffff8d6935a8
R13: 0000000000000001 R14: 0000000000000001 R15: 1ffff11027fc9000
 default_idle_call+0x81/0xc0 kernel/sched/idle.c:112
 cpuidle_idle_call kernel/sched/idle.c:194 [inline]
 do_idle+0x21b/0x5b0 kernel/sched/idle.c:306
 cpu_startup_entry+0x14/0x20 kernel/sched/idle.c:403
 start_secondary+0x31f/0x430 arch/x86/kernel/smpboot.c:281
 secondary_startup_64_no_verify+0xb1/0xbb
 </TASK>
NMI backtrace for cpu 0
CPU: 0 PID: 5184 Comm: syz.0.260 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025
Call Trace:
 <IRQ>
 dump_stack_lvl+0x168/0x230 lib/dump_stack.c:106
 nmi_cpu_backtrace+0x397/0x3d0 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_dump_cpu_stacks+0x22f/0x380 kernel/rcu/tree_stall.h:349
 print_cpu_stall+0x31d/0x5f0 kernel/rcu/tree_stall.h:633
 check_cpu_stall kernel/rcu/tree_stall.h:727 [inline]
 rcu_pending kernel/rcu/tree.c:3936 [inline]
 rcu_sched_clock_irq+0x6d8/0x1110 kernel/rcu/tree.c:2619
 update_process_times+0x193/0x200 kernel/time/timer.c:1818
 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+0x4fe/0xc40 kernel/time/hrtimer.c:1749
 hrtimer_interrupt+0x3bb/0x8d0 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:seqcount_lockdep_reader_access+0x17b/0x1c0 include/linux/seqlock.h:106
Code: 00 4d 85 e4 75 16 e8 54 cc 0f 00 eb 15 e8 4d cc 0f 00 e8 88 e7 39 08 4d 85 e4 74 ea e8 3e cc 0f 00 fb 48 c7 04 24 0e 36 e0 45 <4b> c7 04 3e 00 00 00 00 66 43 c7 44 3e 09 00 00 43 c6 44 3e 0b 00
RSP: 0000:ffffc90000007440 EFLAGS: 00000246
RAX: ffffffff8167ffd2 RBX: 0000000000000000 RCX: ffff888025573b80
RDX: 0000000000000100 RSI: 0000000000000000 RDI: 0000000000000000
RBP: ffffc900000074f8 R08: dffffc0000000000 R09: fffffbfff1ff5438
R10: fffffbfff1ff5438 R11: 1ffffffff1ff5437 R12: 0000000000000200
R13: 000001fb63109b96 R14: 1ffff92000000e88 R15: dffffc0000000000
 timekeeping_get_delta kernel/time/timekeeping.c:254 [inline]
 timekeeping_get_ns kernel/time/timekeeping.c:388 [inline]
 ktime_get_with_offset+0xff/0x320 kernel/time/timekeeping.c:874
 ktime_get_real include/linux/timekeeping.h:79 [inline]
 __net_timestamp include/linux/skbuff.h:3970 [inline]
 netif_rx_internal+0x37a/0x540 net/core/dev.c:4966
 netif_rx+0x94/0x380 net/core/dev.c:5018
 veth_forward_skb drivers/net/veth.c:297 [inline]
 veth_xmit+0x62f/0xa90 drivers/net/veth.c:350
 __netdev_start_xmit include/linux/netdevice.h:5036 [inline]
 netdev_start_xmit include/linux/netdevice.h:5050 [inline]
 xmit_one net/core/dev.c:3649 [inline]
 dev_hard_start_xmit+0x2a5/0x7e0 net/core/dev.c:3665
 __dev_queue_xmit+0x19df/0x2ed0 net/core/dev.c:4288
 hsr_xmit net/hsr/hsr_forward.c:338 [inline]
 hsr_forward_do net/hsr/hsr_forward.c:429 [inline]
 hsr_forward_skb+0xfb4/0x16e0 net/hsr/hsr_forward.c:582
 send_hsr_supervision_frame+0x5f7/0xb80 net/hsr/hsr_device.c:349
 hsr_announce+0x162/0x300 net/hsr/hsr_device.c:405
 call_timer_fn+0x16c/0x530 kernel/time/timer.c:1451
 expire_timers kernel/time/timer.c:1496 [inline]
 __run_timers+0x525/0x7c0 kernel/time/timer.c:1767
 run_timer_softirq+0x63/0xf0 kernel/time/timer.c:1780
 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:preempt_schedule_irq+0xac/0x150 kernel/sched/core.c:6799
Code: 44 24 20 f6 44 24 21 02 74 0b 0f 0b 48 f7 03 08 00 00 00 74 70 bf 01 00 00 00 e8 af 44 a7 f7 e8 fa bd d3 f7 fb bf 01 00 00 00 <e8> ef b5 ff ff 48 c7 44 24 40 00 00 00 00 9c 8f 44 24 40 8b 44 24
RSP: 0000:ffffc9000342fda0 EFLAGS: 00000286
RAX: 06df074cee769900 RBX: 0000000000000000 RCX: 06df074cee769900
RDX: dffffc0000000000 RSI: ffffffff8a0b1be0 RDI: 0000000000000001
RBP: ffffc9000342fe50 R08: dffffc0000000000 R09: ffffed1017207662
R10: ffffed1017207662 R11: 1ffff11017207661 R12: 0000000000000000
R13: 0000000000000000 R14: dffffc0000000000 R15: 1ffff92000685fb4
 irqentry_exit+0x63/0x70 kernel/entry/common.c:432
 asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:676
RIP: 0010:exit_to_user_mode_loop+0x40/0x130 kernel/entry/common.c:168
Code: fb eb 1d e8 22 c5 3b 08 65 48 8b 05 8a 3d 9c 7e 4c 8b 30 41 f7 c6 0e 30 02 00 0f 84 ed 00 00 00 e8 a5 b7 17 00 fb 41 f6 c6 08 <74> 05 e8 29 f3 43 08 41 f7 c6 00 10 00 00 74 08 48 89 df e8 18 d9
RSP: 0000:ffffc9000342ff10 EFLAGS: 00000202
RAX: 06df074cee769900 RBX: ffffc9000342ff58 RCX: 06df074cee769900
RDX: dffffc0000000000 RSI: ffffffff8a0b1be0 RDI: ffffffff8a59e800
RBP: 0000000000000000 R08: dffffc0000000000 R09: ffffed1017207662
R10: ffffed1017207662 R11: 1ffff11017207661 R12: 0000000000000000
R13: 0000000000000000 R14: 0000000000000008 R15: ffff888025573b80
 exit_to_user_mode_prepare+0xee/0x180 kernel/entry/common.c:214
 irqentry_exit_to_user_mode+0x5/0x30 kernel/entry/common.c:320
 asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:676
RIP: 0033:0x7f1d699ad749
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:00007f1d67c140e8 EFLAGS: 00000246
RAX: 0000000000000000 RBX: 00007f1d69c03fa8 RCX: 00007f1d699ad749
RDX: 00000000000f4240 RSI: 0000000000000081 RDI: 00007f1d69c03fac
RBP: 00007f1d69c03fa0 R08: 00358d0deade2da2 R09: 0000000000000000
R10: 0000000000000007 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f1d69c04038 R14: 00007ffe5fe24900 R15: 00007ffe5fe249e8
 </TASK>