rcu: INFO: rcu_preempt self-detected stall on CPU rcu: 0-...!: (1 GPs behind) idle=723/1/0x4000000000000000 softirq=15694/15695 fqs=210 (t=10502 jiffies g=16221 q=693) rcu: rcu_preempt kthread timer wakeup didn't happen for 10082 jiffies! g16221 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x402 rcu: Possible timer handling issue on cpu=1 timer-softirq=7792 rcu: rcu_preempt kthread starved for 10085 jiffies! g16221 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:27848 pid: 15 ppid: 2 flags:0x00004000 Call Trace: context_switch kernel/sched/core.c:5030 [inline] __schedule+0x11b8/0x43b0 kernel/sched/core.c:6376 schedule+0x11b/0x1e0 kernel/sched/core.c:6459 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 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 5.15.189-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025 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 5f da 49 00 44 38 e3 75 10 66 90 0f 00 2d 61 63 d4 08 fb f4 33 ff ff ff fb e9 2d ff ff ff e8 7f 25 74 08 89 f9 80 e1 07 38 RSP: 0018:ffffc90000dd0300 EFLAGS: 00000246 RAX: 9130e4d8bf339c00 RBX: 0000000000000003 RCX: 9130e4d8bf339c00 RDX: dffffc0000000000 RSI: ffffffff8a0b15c0 RDI: ffffffff8a599340 RBP: ffffc90000dd03b0 R08: dffffc0000000000 R09: fffffbfff1ff6e32 R10: fffffbfff1ff6e32 R11: 1ffffffff1ff6e31 R12: 0000000000000003 R13: ffff8880b913b114 R14: dffffc0000000000 R15: 1ffff920001ba060 FS: 0000000000000000(0000) GS:ffff8880b9100000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f6b8b1aa744 CR3: 00000000222fb000 CR4: 00000000003506e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: 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 include/linux/spinlock.h:363 [inline] __dev_xmit_skb net/core/dev.c:3911 [inline] __dev_queue_xmit+0xb8a/0x2ed0 net/core/dev.c:4253 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:3957 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 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:729 Code: bf 48 89 df e8 a6 aa 0a f8 eb b5 e8 4f b0 f6 ff 00 00 cc cc 00 00 cc cc 00 00 cc cc 00 00 cc 66 90 0f 00 2d e7 44 54 00 fb f4 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: 9130e4d8bf339c00 RBX: ffff88813fe48000 RCX: 9130e4d8bf339c00 RDX: 0000000000000001 RSI: ffffffff8a0b15c0 RDI: ffffffff8a599340 RBP: ffffc90000d67e80 R08: dffffc0000000000 R09: ffffed101722765a R10: ffffed101722765a R11: 1ffff11017227659 R12: ffffffff8d696ea8 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 NMI backtrace for cpu 0 CPU: 0 PID: 4185 Comm: kworker/0:4 Not tainted 5.15.189-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025 Workqueue: mld mld_ifc_work Call Trace: 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:1690 [inline] __hrtimer_run_queues+0x4fe/0xc40 kernel/time/hrtimer.c:1754 hrtimer_interrupt+0x3bb/0x8d0 kernel/time/hrtimer.c:1816 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+0x9b/0xc0 arch/x86/kernel/apic/apic.c:1108 asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:676 RIP: 0010:get_current arch/x86/include/asm/current.h:15 [inline] RIP: 0010:__sanitizer_cov_trace_pc+0x4/0x60 kernel/kcov.c:205 Code: 84 00 00 00 00 00 53 48 89 fb e8 17 00 00 00 48 8b 3d c0 ac f1 0b 48 89 de 5b e9 77 99 43 00 00 00 cc cc 00 00 cc 48 8b 04 24 <65> 48 8b 0d 94 ab 8a 7e 65 8b 15 95 ab 8a 7e 81 e2 00 01 ff 00 74 RSP: 0018:ffffc90002ebf438 EFLAGS: 00000282 RAX: ffffffff88085bb4 RBX: ffff888025288980 RCX: ffff88807b615940 RDX: 0000000000000000 RSI: 185b742c101b6a1e RDI: 185b742c101b1260 RBP: ffffc90002ebf5b8 R08: dffffc0000000000 R09: ffffed1003f8ac5d R10: ffffed1003f8ac5d R11: 1ffff11003f8ac5c R12: dffffc0000000000 R13: 185b742c101b6a1e R14: ffff88801fc56000 R15: ffff888065ace000 get_packet_txtime net/sched/sch_taprio.c:383 [inline] taprio_enqueue_one+0xb14/0x1590 net/sched/sch_taprio.c:426 dev_qdisc_enqueue+0x48/0x210 net/core/dev.c:3852 __dev_xmit_skb net/core/dev.c:3936 [inline] __dev_queue_xmit+0xd7e/0x2ed0 net/core/dev.c:4253 neigh_hh_output include/net/neighbour.h:493 [inline] neigh_output include/net/neighbour.h:507 [inline] ip6_finish_output2+0x1035/0x1500 net/ipv6/ip6_output.c:130 dst_output include/net/dst.h:452 [inline] NF_HOOK+0x15f/0x430 include/linux/netfilter.h:302 mld_sendpack+0x713/0xc30 net/ipv6/mcast.c:1826 mld_send_cr net/ipv6/mcast.c:2127 [inline] mld_ifc_work+0x836/0xb40 net/ipv6/mcast.c:2659 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