rcu: INFO: rcu_preempt self-detected stall on CPU
rcu: 	0-...!: (10500 ticks this GP) idle=4a1/1/0x4000000000000000 softirq=7583/7583 fqs=0 
	(t=10501 jiffies g=8733 q=733)
rcu: rcu_preempt kthread starved for 10502 jiffies! g8733 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x0 ->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:R  running task     stack:27800 pid:   15 ppid:     2 flags:0x00004000
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5049 [inline]
 __schedule+0x11ef/0x43c0 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/0x11d0 kernel/rcu/tree.c:1972
 rcu_gp_kthread+0x9b/0x370 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:
NMI backtrace for cpu 0
CPU: 0 PID: 4564 Comm: syz.3.63 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/18/2026
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_cpu_stall+0x318/0x5f0 kernel/rcu/tree_stall.h:631
 check_cpu_stall kernel/rcu/tree_stall.h:727 [inline]
 rcu_pending kernel/rcu/tree.c:3936 [inline]
 rcu_sched_clock_irq+0x6ea/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+0x4b4/0xb70 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+0x196/0x1d0 include/linux/seqlock.h:106
Code: 00 4d 85 e4 75 16 e8 a9 fc 0f 00 eb 15 e8 a2 fc 0f 00 e8 bd 91 53 08 4d 85 e4 74 ea e8 93 fc 0f 00 fb 48 c7 04 24 0e 36 e0 45 <4b> c7 04 3e 00 00 00 00 43 c7 44 3e 08 00 00 00 00 65 48 8b 04 25
RSP: 0018:ffffc90000006e60 EFLAGS: 00000246
RAX: ffffffff816937fd RBX: 0000000000000000 RCX: ffff88802201bb80
RDX: 0000000000000100 RSI: 0000000000000000 RDI: 0000000000000000
RBP: ffffc90000006f18 R08: ffffffff901d51df R09: 1ffffffff203aa3b
R10: dffffc0000000000 R11: fffffbfff203aa3c R12: 0000000000000200
R13: 000001fb63109b96 R14: 1ffff92000000dcc R15: dffffc0000000000
 ktime_get_with_offset+0x90/0x320 kernel/time/timekeeping.c:872
 ktime_get_real include/linux/timekeeping.h:79 [inline]
 __net_timestamp include/linux/skbuff.h:3970 [inline]
 netif_rx_internal+0x380/0x560 net/core/dev.c:4992
 netif_rx+0x94/0x380 net/core/dev.c:5044
 veth_forward_skb drivers/net/veth.c:297 [inline]
 veth_xmit+0x605/0xa60 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:3662 [inline]
 dev_hard_start_xmit+0x2a5/0x7e0 net/core/dev.c:3678
 __dev_queue_xmit+0x1a9b/0x2f80 net/core/dev.c:4305
 hsr_xmit net/hsr/hsr_forward.c:340 [inline]
 hsr_forward_do net/hsr/hsr_forward.c:431 [inline]
 hsr_forward_skb+0xfd2/0x1700 net/hsr/hsr_forward.c:584
 hsr_dev_xmit+0x1c2/0x2e0 net/hsr/hsr_device.c:241
 __netdev_start_xmit include/linux/netdevice.h:5036 [inline]
 netdev_start_xmit include/linux/netdevice.h:5050 [inline]
 xmit_one net/core/dev.c:3662 [inline]
 dev_hard_start_xmit+0x2a5/0x7e0 net/core/dev.c:3678
 __dev_queue_xmit+0x1a9b/0x2f80 net/core/dev.c:4305
 neigh_output include/net/neighbour.h:509 [inline]
 ip6_finish_output2+0x108c/0x1510 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+0xc2a/0x1500 net/ipv6/ndisc.c:513
 addrconf_rs_timer+0x2d1/0x630 net/ipv6/addrconf.c:3956
 call_timer_fn+0x17b/0x540 kernel/time/timer.c:1648
 expire_timers kernel/time/timer.c:1699 [inline]
 __run_timers+0x53e/0x800 kernel/time/timer.c:1970
 run_timer_softirq+0x63/0xf0 kernel/time/timer.c:1983
 handle_softirqs+0x339/0x830 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:mark_wake_futex+0x0/0x150 kernel/futex/core.c:1536
Code: c1 03 38 c1 0f 8c 43 ff ff ff 48 c7 c7 c4 23 8a 8d e8 74 c8 50 00 e9 32 ff ff ff 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 00 <55> 41 57 41 56 41 55 41 54 53 49 89 f6 48 89 fb 49 bd 00 00 00 00
RSP: 0018:ffffc9000420fb78 EFLAGS: 00000297
RAX: ffffffff816d0359 RBX: 00000000ffffffff RCX: ffff88802201bb80
RDX: 0000000000000000 RSI: ffffc900041ffb90 RDI: ffffc9000420fc00
RBP: ffffc9000420fc70 R08: 0000000000000003 R09: 0000000000000004
R10: dffffc0000000000 R11: fffff52000841f60 R12: ffffc90000e0d148
R13: dffffc0000000000 R14: ffffc900041ffb90 R15: 00000000ffffffff
 futex_wake+0x3c2/0x540 kernel/futex/core.c:1695
 do_futex+0xd73/0x12b0 kernel/futex/core.c:3988
 __do_sys_futex kernel/futex/core.c:4060 [inline]
 __se_sys_futex+0x389/0x420 kernel/futex/core.c:4041
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x66/0xd0
RIP: 0033:0x7f8893619dd9
Code: ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 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 e8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007f8892c7b0e8 EFLAGS: 00000246 ORIG_RAX: 00000000000000ca
RAX: ffffffffffffffda RBX: 00007f8893892fa8 RCX: 00007f8893619dd9
RDX: 00000000000f4240 RSI: 0000000000000081 RDI: 00007f8893892fac
RBP: 00007f8893892fa0 R08: 0035de9a766d276a R09: 0000000000000000
R10: 0000000000000004 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f8893893038 R14: 00007fff12702f30 R15: 00007fff12703018
 </TASK>
NMI backtrace for cpu 0
CPU: 0 PID: 4564 Comm: syz.3.63 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/18/2026
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_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+0x6ea/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+0x4b4/0xb70 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+0x196/0x1d0 include/linux/seqlock.h:106
Code: 00 4d 85 e4 75 16 e8 a9 fc 0f 00 eb 15 e8 a2 fc 0f 00 e8 bd 91 53 08 4d 85 e4 74 ea e8 93 fc 0f 00 fb 48 c7 04 24 0e 36 e0 45 <4b> c7 04 3e 00 00 00 00 43 c7 44 3e 08 00 00 00 00 65 48 8b 04 25
RSP: 0018:ffffc90000006e60 EFLAGS: 00000246
RAX: ffffffff816937fd RBX: 0000000000000000 RCX: ffff88802201bb80
RDX: 0000000000000100 RSI: 0000000000000000 RDI: 0000000000000000
RBP: ffffc90000006f18 R08: ffffffff901d51df R09: 1ffffffff203aa3b
R10: dffffc0000000000 R11: fffffbfff203aa3c R12: 0000000000000200
R13: 000001fb63109b96 R14: 1ffff92000000dcc R15: dffffc0000000000
 ktime_get_with_offset+0x90/0x320 kernel/time/timekeeping.c:872
 ktime_get_real include/linux/timekeeping.h:79 [inline]
 __net_timestamp include/linux/skbuff.h:3970 [inline]
 netif_rx_internal+0x380/0x560 net/core/dev.c:4992
 netif_rx+0x94/0x380 net/core/dev.c:5044
 veth_forward_skb drivers/net/veth.c:297 [inline]
 veth_xmit+0x605/0xa60 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:3662 [inline]
 dev_hard_start_xmit+0x2a5/0x7e0 net/core/dev.c:3678
 __dev_queue_xmit+0x1a9b/0x2f80 net/core/dev.c:4305
 hsr_xmit net/hsr/hsr_forward.c:340 [inline]
 hsr_forward_do net/hsr/hsr_forward.c:431 [inline]
 hsr_forward_skb+0xfd2/0x1700 net/hsr/hsr_forward.c:584
 hsr_dev_xmit+0x1c2/0x2e0 net/hsr/hsr_device.c:241
 __netdev_start_xmit include/linux/netdevice.h:5036 [inline]
 netdev_start_xmit include/linux/netdevice.h:5050 [inline]
 xmit_one net/core/dev.c:3662 [inline]
 dev_hard_start_xmit+0x2a5/0x7e0 net/core/dev.c:3678
 __dev_queue_xmit+0x1a9b/0x2f80 net/core/dev.c:4305
 neigh_output include/net/neighbour.h:509 [inline]
 ip6_finish_output2+0x108c/0x1510 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+0xc2a/0x1500 net/ipv6/ndisc.c:513
 addrconf_rs_timer+0x2d1/0x630 net/ipv6/addrconf.c:3956
 call_timer_fn+0x17b/0x540 kernel/time/timer.c:1648
 expire_timers kernel/time/timer.c:1699 [inline]
 __run_timers+0x53e/0x800 kernel/time/timer.c:1970
 run_timer_softirq+0x63/0xf0 kernel/time/timer.c:1983
 handle_softirqs+0x339/0x830 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:mark_wake_futex+0x0/0x150 kernel/futex/core.c:1536
Code: c1 03 38 c1 0f 8c 43 ff ff ff 48 c7 c7 c4 23 8a 8d e8 74 c8 50 00 e9 32 ff ff ff 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 00 <55> 41 57 41 56 41 55 41 54 53 49 89 f6 48 89 fb 49 bd 00 00 00 00
RSP: 0018:ffffc9000420fb78 EFLAGS: 00000297
RAX: ffffffff816d0359 RBX: 00000000ffffffff RCX: ffff88802201bb80
RDX: 0000000000000000 RSI: ffffc900041ffb90 RDI: ffffc9000420fc00
RBP: ffffc9000420fc70 R08: 0000000000000003 R09: 0000000000000004
R10: dffffc0000000000 R11: fffff52000841f60 R12: ffffc90000e0d148
R13: dffffc0000000000 R14: ffffc900041ffb90 R15: 00000000ffffffff
 futex_wake+0x3c2/0x540 kernel/futex/core.c:1695
 do_futex+0xd73/0x12b0 kernel/futex/core.c:3988
 __do_sys_futex kernel/futex/core.c:4060 [inline]
 __se_sys_futex+0x389/0x420 kernel/futex/core.c:4041
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x66/0xd0
RIP: 0033:0x7f8893619dd9
Code: ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 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 e8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007f8892c7b0e8 EFLAGS: 00000246 ORIG_RAX: 00000000000000ca
RAX: ffffffffffffffda RBX: 00007f8893892fa8 RCX: 00007f8893619dd9
RDX: 00000000000f4240 RSI: 0000000000000081 RDI: 00007f8893892fac
RBP: 00007f8893892fa0 R08: 0035de9a766d276a R09: 0000000000000000
R10: 0000000000000004 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f8893893038 R14: 00007fff12702f30 R15: 00007fff12703018
 </TASK>