bridge0: received packet on veth1_to_bridge with own address as source address (addr:aa:aa:aa:aa:aa:0c, vlan:1) rcu: INFO: rcu_preempt detected stalls on CPUs/tasks: rcu: (detected by 1, t=10502 jiffies, g=87905, q=38028 ncpus=2) rcu: All QSes seen, last rcu_preempt kthread activity 4031 (4294997878-4294993847), jiffies_till_next_fqs=1, root ->qsmask 0x0 rcu: rcu_preempt kthread starved for 4031 jiffies! g87905 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:27752 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 preempt_schedule_common+0x82/0xd0 kernel/sched/core.c:7413 preempt_schedule_thunk+0x16/0x40 arch/x86/entry/thunk.S:12 __raw_spin_unlock_irqrestore include/linux/spinlock_api_smp.h:179 [inline] _raw_spin_unlock_irqrestore+0x74/0x80 kernel/locking/spinlock.c:198 __mod_timer+0xb53/0xed0 kernel/time/timer.c:1139 schedule_timeout+0x14d/0x2c0 kernel/time/sleep_timeout.c:98 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: CPU: 1 UID: 0 PID: 5760 Comm: kworker/1:8 Not tainted syzkaller #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/09/2026 Workqueue: events_power_efficient neigh_periodic_work RIP: 0010:on_stack arch/x86/include/asm/stacktrace.h:58 [inline] RIP: 0010:stack_access_ok arch/x86/kernel/unwind_orc.c:409 [inline] RIP: 0010:deref_stack_reg arch/x86/kernel/unwind_orc.c:419 [inline] RIP: 0010:unwind_next_frame+0xba9/0x2550 arch/x86/kernel/unwind_orc.c:614 Code: ff df 48 8b 4c 24 10 0f b6 04 01 84 c0 0f 85 3b 14 00 00 41 83 3e 00 0f 95 c0 49 39 d7 0f 96 c1 20 c1 49 39 d5 0f 97 c0 20 c8 <3c> 01 75 18 48 8d 42 08 4c 39 f8 0f 97 c1 4c 39 e8 0f 96 c0 84 c1 RSP: 0018:ffffc90000a082a0 EFLAGS: 00000202 RAX: 0000000000000001 RBX: 1ffff9200014106a RCX: 1ffff92000141001 RDX: ffffc90000a08d38 RSI: 0000000000000002 RDI: ffffc90000a08358 RBP: 1ffffffff22efccb R08: ffffc90000a08d40 R09: 0000000000000000 R10: 0000000000000000 R11: ffffffff8eb59c60 R12: 1ffff9200014106b R13: ffffc90000a09000 R14: ffffc90000a08348 R15: ffffc90000a01000 FS: 0000000000000000(0000) GS:ffff88812505e000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007faba3e23e80 CR3: 000000007b486000 CR4: 00000000003526f0 Call Trace: arch_stack_walk+0x11b/0x150 arch/x86/kernel/stacktrace.c:25 stack_trace_save+0xa9/0x100 kernel/stacktrace.c:122 kasan_save_stack mm/kasan/common.c:57 [inline] kasan_save_track+0x3e/0x80 mm/kasan/common.c:78 unpoison_slab_object mm/kasan/common.c:340 [inline] __kasan_slab_alloc+0x6c/0x80 mm/kasan/common.c:366 kasan_slab_alloc include/linux/kasan.h:253 [inline] slab_post_alloc_hook mm/slub.c:4612 [inline] slab_alloc_node mm/slub.c:4945 [inline] kmem_cache_alloc_noprof+0x2a0/0x5f0 mm/slub.c:4959 __skb_ext_alloc net/core/skbuff.c:7094 [inline] skb_ext_add+0x148/0x8e0 net/core/skbuff.c:7198 nf_bridge_alloc include/net/netfilter/br_netfilter.h:12 [inline] br_nf_pre_routing+0xc52/0x14b0 net/bridge/br_netfilter_hooks.c:528 nf_hook_entry_hookfn include/linux/netfilter.h:165 [inline] nf_hook_bridge_pre net/bridge/br_input.c:291 [inline] br_handle_frame+0x127f/0x1510 net/bridge/br_input.c:442 __netif_receive_skb_core+0x989/0x30b0 net/core/dev.c:6096 __netif_receive_skb_one_core net/core/dev.c:6207 [inline] __netif_receive_skb net/core/dev.c:6322 [inline] process_backlog+0x706/0x1860 net/core/dev.c:6673 __napi_poll+0xaa/0x330 net/core/dev.c:7732 napi_poll net/core/dev.c:7795 [inline] net_rx_action+0x61d/0xf50 net/core/dev.c:7952 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:should_resched arch/x86/include/asm/preempt.h:104 [inline] RIP: 0010:__local_bh_enable_ip+0xd8/0x130 kernel/softirq.c:457 Code: 8b e8 8c 23 47 0a 65 66 8b 05 9c 30 e4 11 66 85 c0 75 32 bf 01 00 00 00 e8 85 f0 0b 00 e8 c0 be 46 00 fb 65 8b 05 78 30 e4 11 <85> c0 75 05 e8 3f 7f ab ff 5b 41 5e e9 57 06 4a 0a cc 90 0f 0b 90 RSP: 0018:ffffc900050e7a68 EFLAGS: 00000202 RAX: 0000000080000000 RBX: 0000000000000201 RCX: 0000000000000046 RDX: 0000000000000006 RSI: ffffffff8e22ba3a RDI: ffffffff8c4bd380 RBP: 0000000000000000 R08: ffffffff905775f7 R09: 1ffffffff20aeebe R10: dffffc0000000000 R11: fffffbfff20aeebf R12: 0000000100007750 R13: 0000000000000000 R14: ffffffff89a697d3 R15: 1ffff1100af21000 spin_unlock_bh include/linux/spinlock.h:396 [inline] neigh_periodic_work+0xc23/0xe40 net/core/neighbour.c:1035 process_one_work kernel/workqueue.c:3322 [inline] process_scheduled_works+0xa8e/0x14e0 kernel/workqueue.c:3405 worker_thread+0xa47/0xfb0 kernel/workqueue.c:3486 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 bridge0: received packet on veth1_to_bridge with own address as source address (addr:aa:aa:aa:aa:aa:0c, vlan:1) bridge0: received packet on bridge_slave_1 with own address as source address (addr:aa:aa:aa:aa:aa:0c, vlan:1) bridge0: received packet on veth1_to_bridge with own address as source address (addr:aa:aa:aa:aa:aa:0c, vlan:1) bridge0: received packet on veth1_to_bridge with own address as source address (addr:aa:aa:aa:aa:aa:0c, vlan:1) net_ratelimit: 13466 callbacks suppressed bridge0: received packet on veth1_to_bridge with own address as source address (addr:aa:aa:aa:aa:aa:0c, vlan:1) bridge0: received packet on veth1_to_bridge with own address as source address (addr:aa:aa:aa:aa:aa:0c, vlan:1) bridge0: received packet on bridge_slave_1 with own address as source address (addr:aa:aa:aa:aa:aa:0c, vlan:1) bridge0: received packet on veth1_to_bridge with own address as source address (addr:aa:aa:aa:aa:aa:0c, vlan:1) bridge0: received packet on bridge_slave_1 with own address as source address (addr:aa:aa:aa:aa:aa:0c, vlan:1) bridge0: received packet on bridge_slave_1 with own address as source address (addr:aa:aa:aa:aa:aa:0c, vlan:1) bridge0: received packet on bridge_slave_1 with own address as source address (addr:aa:aa:aa:aa:aa:0c, vlan:1) bridge0: received packet on veth1_to_bridge with own address as source address (addr:aa:aa:aa:aa:aa:0c, vlan:1)