IPVS: wrr: UDP 224.0.0.2:0 - no destination available IPVS: wrr: UDP 224.0.0.2:0 - no destination available IPVS: wrr: UDP 224.0.0.2:0 - no destination available IPVS: wrr: UDP 224.0.0.2:0 - no destination available rcu: INFO: rcu_preempt detected stalls on CPUs/tasks: rcu: (detected by 0, t=10502 jiffies, g=264345, q=1163 ncpus=2) rcu: All QSes seen, last rcu_preempt kthread activity 3108 (4295095781-4295092673), jiffies_till_next_fqs=1, root ->qsmask 0x0 rcu: rcu_preempt kthread starved for 3108 jiffies! g264345 f0x2 RCU_GP_WAIT_FQS(5) ->state=0x0 ->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:R running task stack:27736 pid:16 tgid:16 ppid:2 task_flags:0x208040 flags:0x00080000 Call Trace: context_switch kernel/sched/core.c:5510 [inline] __schedule+0x17d9/0x56c0 kernel/sched/core.c:7234 __schedule_loop kernel/sched/core.c:7311 [inline] schedule+0x164/0x2b0 kernel/sched/core.c:7326 schedule_timeout+0x152/0x2c0 kernel/time/sleep_timeout.c:99 rcu_gp_fqs_loop+0x30c/0x11f0 kernel/rcu/tree.c:2123 rcu_gp_kthread+0x9e/0x2b0 kernel/rcu/tree.c:2325 kthread+0x388/0x470 kernel/kthread.c:436 ret_from_fork+0x514/0xb70 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 rcu: Stack dump where RCU GP kthread last ran: Sending NMI from CPU 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 UID: 0 PID: 6474 Comm: kworker/R-bond2 Not tainted syzkaller #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/24/2026 Workqueue: bond2 bond_alb_monitor RIP: 0010:check_kcov_mode kernel/kcov.c:183 [inline] RIP: 0010:write_comp_data kernel/kcov.c:246 [inline] RIP: 0010:__sanitizer_cov_trace_const_cmp8+0x2e/0x90 kernel/kcov.c:321 Code: 48 8b 04 24 65 48 8b 0d 98 f9 a5 11 65 8b 15 b9 f9 a5 11 81 e2 00 01 ff 00 74 11 81 fa 00 01 00 00 75 57 83 b9 24 17 00 00 00 <74> 4e 8b 91 f8 16 00 00 83 fa 03 75 43 48 8b 91 00 17 00 00 44 8b RSP: 0018:ffffc90000a08098 EFLAGS: 00000246 RAX: ffffffff8a5f3af8 RBX: 0000000000000000 RCX: ffff888078aebe00 RDX: 0000000000000100 RSI: 0000000000000000 RDI: 0000000000000000 RBP: ffffc90000a08268 R08: ffff888045c09743 R09: 1ffff11008b812e8 R10: dffffc0000000000 R11: ffffed1008b812e9 R12: 1ffff11030a41201 R13: 0000000000000001 R14: dffffc0000000000 R15: ffff888045c09700 FS: 0000000000000000(0000) GS:ffff888125050000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000200000002340 CR3: 0000000074fd6000 CR4: 00000000003526f0 Call Trace: skb_dst_check_unset include/linux/skbuff.h:1170 [inline] skb_dst_set include/linux/skbuff.h:1217 [inline] ip_route_me_harder+0x828/0xfe0 net/ipv4/netfilter.c:60 synproxy_send_tcp+0x347/0x670 net/netfilter/nf_synproxy_core.c:434 synproxy_send_client_synack+0x89b/0xde0 net/netfilter/nf_synproxy_core.c:487 nft_synproxy_eval_v4+0x362/0x4e0 net/netfilter/nft_synproxy.c:59 nft_synproxy_do_eval+0x335/0x550 net/netfilter/nft_synproxy.c:141 expr_call_ops_eval net/netfilter/nf_tables_core.c:237 [inline] nft_do_chain+0x48d/0x1b10 net/netfilter/nf_tables_core.c:285 nft_do_chain_inet+0x360/0x4b0 net/netfilter/nft_chain_filter.c:162 nf_hook_entry_hookfn include/linux/netfilter.h:158 [inline] nf_hook_slow+0xc5/0x220 net/netfilter/core.c:619 nf_hook include/linux/netfilter.h:273 [inline] NF_HOOK+0x21f/0x3c0 include/linux/netfilter.h:316 NF_HOOK+0x336/0x3c0 include/linux/netfilter.h:318 __netif_receive_skb_one_core net/core/dev.c:6212 [inline] __netif_receive_skb net/core/dev.c:6325 [inline] process_backlog+0xa34/0x1860 net/core/dev.c:6676 __napi_poll+0xaa/0x330 net/core/dev.c:7735 napi_poll net/core/dev.c:7798 [inline] net_rx_action+0x61d/0xf50 net/core/dev.c:7955 handle_softirqs+0x225/0x840 kernel/softirq.c:622 __do_softirq kernel/softirq.c:656 [inline] invoke_softirq kernel/softirq.c:496 [inline] __irq_exit_rcu+0xca/0x220 kernel/softirq.c:735 irq_exit_rcu+0x9/0x30 kernel/softirq.c:752 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1062 [inline] sysvec_apic_timer_interrupt+0xa6/0xc0 arch/x86/kernel/apic/apic.c:1062 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:674 RIP: 0010:__raw_spin_unlock_irq include/linux/spinlock_api_smp.h:188 [inline] RIP: 0010:_raw_spin_unlock_irq+0x29/0x50 kernel/locking/spinlock.c:206 Code: 90 f3 0f 1e fa 53 48 89 fb 48 83 c7 18 48 8b 74 24 08 e8 ca 06 cf f5 48 89 df e8 22 7c cf f5 e8 1d 5e fb f5 fb bf 01 00 00 00 42 92 c0 f5 65 8b 05 3b 22 99 07 85 c0 74 07 5b c3 cc cc cc cc RSP: 0018:ffffc9000cbdfad0 EFLAGS: 00000202 RAX: 0000000000125549 RBX: ffff88801b0cb000 RCX: 0000000080000001 RDX: 0000000000000000 RSI: ffffffff8e22c937 RDI: 0000000000000001 RBP: ffffc9000cbdfce0 R08: ffffffff90578f37 R09: 1ffffffff20af1e6 R10: dffffc0000000000 R11: fffffbfff20af1e7 R12: 0000000002000000 R13: dffffc0000000000 R14: 0000000000000000 R15: ffff88805a235378 process_one_work kernel/workqueue.c:3291 [inline] process_scheduled_works+0x90f/0x14e0 kernel/workqueue.c:3405 rescuer_thread+0x7b6/0x10b0 kernel/workqueue.c:3629 kthread+0x388/0x470 kernel/kthread.c:436 ret_from_fork+0x514/0xb70 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 IPVS: wrr: UDP 224.0.0.2:0 - no destination available IPVS: wrr: UDP 224.0.0.2:0 - no destination available IPVS: wrr: UDP 224.0.0.2:0 - no destination available IPVS: wrr: UDP 224.0.0.2:0 - no destination available IPVS: wrr: UDP 224.0.0.2:0 - no destination available IPVS: wrr: UDP 224.0.0.2:0 - no destination available IPVS: wrr: UDP 224.0.0.2:0 - no destination available IPVS: wrr: UDP 224.0.0.2:0 - no destination available IPVS: wrr: UDP 224.0.0.2:0 - no destination available