IPVS: ovf: UDP 224.0.0.1:0 - no destination available IPVS: ovf: UDP 224.0.0.1:0 - no destination available IPVS: ovf: UDP 224.0.0.1:0 - no destination available IPVS: ovf: UDP 224.0.0.1:0 - no destination available rcu: INFO: rcu_preempt detected stalls on CPUs/tasks: rcu: 1-...!: (1 GPs behind) idle=86cc/1/0x4000000000000000 softirq=63604/63605 fqs=2 rcu: (detected by 0, t=10506 jiffies, g=97653, q=152 ncpus=2) Sending NMI from CPU 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 PID: 15242 Comm: syz.0.3516 Not tainted syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/18/2026 RIP: 0010:check_preemption_disabled+0x37/0x110 lib/smp_processor_id.c:55 Code: 04 25 28 00 00 00 48 89 44 24 08 65 8b 05 bd 25 7d 75 65 8b 0d b2 25 7d 75 f7 c1 ff ff ff 7f 74 1f 65 48 8b 0c 25 28 00 00 00 <48> 3b 4c 24 08 0f 85 c4 00 00 00 48 83 c4 10 5b 41 5e 41 5f 5d c3 RSP: 0018:ffffc900001f0ae8 EFLAGS: 00000002 RAX: 0000000000000001 RBX: 0000000000000000 RCX: 09fd416023157600 RDX: 0000000000000000 RSI: ffffffff8b1c8fc0 RDI: ffffffff8b1c8f80 RBP: ffffc900001f0c48 R08: ffffffff8e8b19ef R09: 1ffffffff1d1633d R10: dffffc0000000000 R11: fffffbfff1d1633e R12: 1ffff9200003e174 R13: ffff88801afa5300 R14: 0000000000000001 R15: dffffc0000000000 FS: 000055558fd3c500(0000) GS:ffff8880b8f00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000200000003c80 CR3: 000000005d653000 CR4: 00000000003506e0 Call Trace: rcu_dynticks_curr_cpu_in_eqs include/linux/context_tracking.h:122 [inline] rcu_is_watching+0x15/0xb0 kernel/rcu/tree.c:700 trace_lock_acquire include/trace/events/lock.h:24 [inline] lock_acquire+0xc6/0x420 kernel/locking/lockdep.c:5725 __raw_spin_lock include/linux/spinlock_api_smp.h:133 [inline] _raw_spin_lock+0x2e/0x40 kernel/locking/spinlock.c:154 spin_lock include/linux/spinlock.h:351 [inline] advance_sched+0xc5/0xc80 net/sched/sch_taprio.c:940 __run_hrtimer kernel/time/hrtimer.c:1750 [inline] __hrtimer_run_queues+0x520/0xc40 kernel/time/hrtimer.c:1814 hrtimer_interrupt+0x3c9/0x9c0 kernel/time/hrtimer.c:1876 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1077 [inline] __sysvec_apic_timer_interrupt+0xfb/0x3b0 arch/x86/kernel/apic/apic.c:1094 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1088 [inline] sysvec_apic_timer_interrupt+0x9f/0xc0 arch/x86/kernel/apic/apic.c:1088 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:687 RIP: 0010:rep_movs_alternative+0x36/0x90 arch/x86/lib/copy_user_64.S:59 Code: 08 73 21 85 c9 74 0f 8a 06 88 07 48 ff c7 48 ff c6 48 ff c9 75 f1 c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 00 48 8b 06 48 89 07 <48> 83 c6 08 48 83 c7 08 83 e9 08 74 df 83 f9 08 73 e8 eb c9 f3 a4 RSP: 0018:ffffc90003ee7bb0 EFLAGS: 00040246 RAX: 0000000000000000 RBX: 0000000000000030 RCX: 0000000000000008 RDX: 0000000000000000 RSI: ffffc90003ee7e28 RDI: 00007ffcb46dec98 RBP: ffffc90003ee7d70 R08: ffffc90003ee7e2f R09: 1ffff920007dcfc5 R10: dffffc0000000000 R11: fffff520007dcfc6 R12: 00007ffcb46deca0 R13: dffffc0000000000 R14: 00007ffcb46dec70 R15: ffffc90003ee7e00 copy_user_generic arch/x86/include/asm/uaccess_64.h:112 [inline] raw_copy_to_user arch/x86/include/asm/uaccess_64.h:133 [inline] _copy_to_user+0x85/0xa0 lib/usercopy.c:41 copy_to_user include/linux/uaccess.h:191 [inline] copy_siginfo_to_user+0x24/0xa0 kernel/signal.c:3372 x64_setup_rt_frame+0x746/0xc40 arch/x86/kernel/signal_64.c:194 setup_rt_frame arch/x86/kernel/signal.c:223 [inline] handle_signal arch/x86/kernel/signal.c:267 [inline] arch_do_signal_or_restart+0x42c/0x800 arch/x86/kernel/signal.c:312 exit_to_user_mode_loop+0x70/0x110 kernel/entry/common.c:174 exit_to_user_mode_prepare+0xee/0x180 kernel/entry/common.c:210 __syscall_exit_to_user_mode_work kernel/entry/common.c:291 [inline] syscall_exit_to_user_mode+0x1a/0x50 kernel/entry/common.c:302 do_syscall_64+0x61/0xa0 arch/x86/entry/common.c:82 entry_SYSCALL_64_after_hwframe+0x68/0xd2 RIP: 0033:0x7f413759cdd9 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:00007ffcb46df0f8 EFLAGS: 00000246 ORIG_RAX: 00000000000000ca RAX: fffffffffffffffc RBX: 0000000000099f85 RCX: 00007f413759cdd9 RDX: 0000000000000000 RSI: 0000000000000080 RDI: 00007f4137815fac RBP: 0000000000000032 R08: 0000000000745d1e R09: 0000000000000000 R10: 00007ffcb46df200 R11: 0000000000000246 R12: 00007ffcb46df220 R13: 00007f4137815fac R14: 0000000000099fb7 R15: 00007ffcb46df200 rcu: rcu_preempt kthread starved for 10495 jiffies! g97653 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:27656 pid:17 ppid:2 flags:0x00004000 Call Trace: context_switch kernel/sched/core.c:5381 [inline] __schedule+0x1553/0x45a0 kernel/sched/core.c:6700 schedule+0xbd/0x170 kernel/sched/core.c:6774 schedule_timeout+0x188/0x2d0 kernel/time/timer.c:2168 rcu_gp_fqs_loop+0x313/0x1590 kernel/rcu/tree.c:1667 rcu_gp_kthread+0x9d/0x3b0 kernel/rcu/tree.c:1866 kthread+0x2fa/0x390 kernel/kthread.c:388 ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:152 ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:293 rcu: Stack dump where RCU GP kthread last ran: CPU: 0 PID: 5959 Comm: kworker/u4:14 Not tainted syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/18/2026 Workqueue: events_unbound toggle_allocation_gate RIP: 0010:csd_lock_wait kernel/smp.c:311 [inline] RIP: 0010:smp_call_function_many_cond+0xdfe/0x1140 kernel/smp.c:855 Code: 45 8b 2c 24 44 89 ee 83 e6 01 31 ff e8 cb f5 0a 00 41 83 e5 01 49 bd 00 00 00 00 00 fc ff df 75 07 e8 06 f2 0a 00 eb 38 f3 90 <42> 0f b6 04 2b 84 c0 75 11 41 f7 04 24 01 00 00 00 74 1e e8 ea f1 RSP: 0018:ffffc90004d37780 EFLAGS: 00000293 RAX: ffffffff817c3016 RBX: 1ffff110171e826d RCX: ffff888026fb9e00 RDX: 0000000000000000 RSI: 0000000000000001 RDI: 0000000000000000 RBP: ffffc90004d37900 R08: ffffffff911c6507 R09: 1ffffffff2238ca0 R10: dffffc0000000000 R11: fffffbfff2238ca1 R12: ffff8880b8f41368 R13: dffffc0000000000 R14: ffff8880b8e3d148 R15: 0000000000000001 FS: 0000000000000000(0000) GS:ffff8880b8e00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f143d1ea4c0 CR3: 000000000cf32000 CR4: 00000000003506f0 Call Trace: on_each_cpu_cond_mask+0x3f/0x80 kernel/smp.c:1022 on_each_cpu include/linux/smp.h:71 [inline] text_poke_sync arch/x86/kernel/alternative.c:2222 [inline] text_poke_bp_batch+0x31e/0x990 arch/x86/kernel/alternative.c:2432 text_poke_flush arch/x86/kernel/alternative.c:2623 [inline] text_poke_finish+0x30/0x50 arch/x86/kernel/alternative.c:2630 arch_jump_label_transform_apply+0x1c/0x30 arch/x86/kernel/jump_label.c:146 static_key_enable_cpuslocked+0x123/0x240 kernel/jump_label.c:207 static_key_enable+0x1a/0x20 kernel/jump_label.c:220 toggle_allocation_gate+0xa8/0x260 mm/kfence/core.c:847 process_one_work kernel/workqueue.c:2653 [inline] process_scheduled_works+0xa5d/0x15d0 kernel/workqueue.c:2730 worker_thread+0xa55/0xfc0 kernel/workqueue.c:2811 kthread+0x2fa/0x390 kernel/kthread.c:388 ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:152 ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:293 IPVS: ovf: UDP 224.0.0.1:0 - no destination available IPVS: ovf: UDP 224.0.0.1:0 - no destination available IPVS: ovf: UDP 224.0.0.1:0 - no destination available IPVS: ovf: UDP 224.0.0.1:0 - no destination available IPVS: ovf: UDP 224.0.0.1:0 - no destination available IPVS: ovf: UDP 224.0.0.1:0 - no destination available IPVS: ovf: UDP 224.0.0.1:0 - no destination available IPVS: ovf: UDP 224.0.0.1:0 - no destination available IPVS: ovf: UDP 224.0.0.1:0 - no destination available IPVS: ovf: UDP 224.0.0.1:0 - no destination available IPVS: ovf: UDP 224.0.0.1:0 - no destination available IPVS: ovf: UDP 224.0.0.1:0 - no destination available IPVS: ovf: UDP 224.0.0.1:0 - no destination available IPVS: ovf: UDP 224.0.0.1:0 - no destination available IPVS: ovf: UDP 224.0.0.1:0 - no destination available IPVS: ovf: UDP 224.0.0.1:0 - no destination available IPVS: ovf: UDP 224.0.0.1:0 - no destination available IPVS: ovf: UDP 224.0.0.1:0 - no destination available