bridge0: received packet on bridge_slave_0 with own address as source address (addr:aa:aa:aa:aa:aa:1b, vlan:0) rcu: INFO: rcu_preempt detected stalls on CPUs/tasks: rcu: (detected by 0, t=10502 jiffies, g=91609, q=2368 ncpus=2) rcu: All QSes seen, last rcu_preempt kthread activity 912 (4295001252-4295000340), jiffies_till_next_fqs=1, root ->qsmask 0x0 rcu: rcu_preempt kthread starved for 913 jiffies! g91609 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:27288 pid:16 tgid:16 ppid:2 task_flags:0x208040 flags:0x00080000 Call Trace: context_switch kernel/sched/core.c:5325 [inline] __schedule+0x1798/0x4cc0 kernel/sched/core.c:6929 __schedule_loop kernel/sched/core.c:7011 [inline] schedule+0x165/0x360 kernel/sched/core.c:7026 schedule_timeout+0x12b/0x270 kernel/time/sleep_timeout.c:99 rcu_gp_fqs_loop+0x301/0x1540 kernel/rcu/tree.c:2083 rcu_gp_kthread+0x99/0x390 kernel/rcu/tree.c:2285 kthread+0x711/0x8a0 kernel/kthread.c:463 ret_from_fork+0x4bc/0x870 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: 14500 Comm: kworker/u8:20 Not tainted syzkaller #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/02/2025 Workqueue: events_unbound toggle_allocation_gate RIP: 0010:br_switchdev_fdb_notify+0x0/0x3e0 net/bridge/br_switchdev.c:148 Code: e8 25 e1 00 f8 4d 89 34 24 e9 52 fe ff ff e8 f7 37 21 01 0f 1f 80 00 00 00 00 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 0f 1e fa 55 48 89 e5 41 57 41 56 41 55 41 54 53 48 83 e4 e0 48 RSP: 0018:ffffc90000a080d8 EFLAGS: 00000246 RAX: ffffffff8a1b89fd RBX: ffff8880672396c8 RCX: ffff88802174dac0 RDX: 000000000000001d RSI: ffff8880672396c0 RDI: ffff888058758d80 RBP: ffffc90000a081b0 R08: ffff8880672396ef R09: 1ffff1100ce472dd R10: dffffc0000000000 R11: ffffed100ce472de R12: ffff8880672396e8 R13: 1ffff1100ce472d9 R14: 0000000000000000 R15: 0000000000000000 FS: 0000000000000000(0000) GS:ffff88812623e000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 000000110c3904d0 CR3: 000000000dd38000 CR4: 00000000003526f0 Call Trace: br_fdb_update+0x4e1/0x690 net/bridge/br_fdb.c:1013 br_handle_frame_finish+0x587/0x1c50 net/bridge/br_input.c:144 br_nf_hook_thresh+0x3c6/0x4a0 net/bridge/br_netfilter_hooks.c:-1 br_nf_pre_routing_finish_ipv6+0x999/0xd60 net/bridge/br_netfilter_ipv6.c:-1 NF_HOOK include/linux/netfilter.h:318 [inline] br_nf_pre_routing_ipv6+0x37e/0x6b0 net/bridge/br_netfilter_ipv6.c:184 nf_hook_entry_hookfn include/linux/netfilter.h:158 [inline] nf_hook_bridge_pre net/bridge/br_input.c:291 [inline] br_handle_frame+0x982/0x14c0 net/bridge/br_input.c:442 __netif_receive_skb_core+0x10b9/0x4380 net/core/dev.c:5966 __netif_receive_skb_one_core net/core/dev.c:6077 [inline] __netif_receive_skb+0x72/0x380 net/core/dev.c:6192 process_backlog+0x60e/0x14f0 net/core/dev.c:6544 __napi_poll+0xc7/0x360 net/core/dev.c:7594 napi_poll net/core/dev.c:7657 [inline] net_rx_action+0x5f7/0xdf0 net/core/dev.c:7784 handle_softirqs+0x286/0x870 kernel/softirq.c:622 __do_softirq kernel/softirq.c:656 [inline] invoke_softirq kernel/softirq.c:496 [inline] __irq_exit_rcu+0xca/0x1f0 kernel/softirq.c:723 irq_exit_rcu+0x9/0x30 kernel/softirq.c:739 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1052 [inline] sysvec_apic_timer_interrupt+0xa6/0xc0 arch/x86/kernel/apic/apic.c:1052 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:697 RIP: 0010:csd_lock_wait kernel/smp.c:342 [inline] RIP: 0010:smp_call_function_many_cond+0xd33/0x12d0 kernel/smp.c:877 Code: 45 8b 2c 24 44 89 ee 83 e6 01 31 ff e8 b6 73 0b 00 41 83 e5 01 49 bd 00 00 00 00 00 fc ff df 75 07 e8 61 6f 0b 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 45 6f RSP: 0018:ffffc9001acc7640 EFLAGS: 00000293 RAX: ffffffff81b494ab RBX: 1ffff11017108441 RCX: ffff88802174dac0 RDX: 0000000000000000 RSI: 0000000000000001 RDI: 0000000000000000 RBP: ffffc9001acc77c0 R08: ffffffff8f7cd377 R09: 1ffffffff1ef9a6e R10: dffffc0000000000 R11: fffffbfff1ef9a6f R12: ffff8880b8842208 R13: dffffc0000000000 R14: ffff8880b893b240 R15: 0000000000000000 on_each_cpu_cond_mask+0x3f/0x80 kernel/smp.c:1043 on_each_cpu include/linux/smp.h:71 [inline] smp_text_poke_sync_each_cpu arch/x86/kernel/alternative.c:2713 [inline] smp_text_poke_batch_finish+0x5f9/0x1130 arch/x86/kernel/alternative.c:2923 arch_jump_label_transform_apply+0x1c/0x30 arch/x86/kernel/jump_label.c:146 static_key_enable_cpuslocked+0x128/0x250 kernel/jump_label.c:210 static_key_enable+0x1a/0x20 kernel/jump_label.c:223 toggle_allocation_gate+0xad/0x240 mm/kfence/core.c:852 process_one_work kernel/workqueue.c:3263 [inline] process_scheduled_works+0xae1/0x17b0 kernel/workqueue.c:3346 worker_thread+0x8a0/0xda0 kernel/workqueue.c:3427 kthread+0x711/0x8a0 kernel/kthread.c:463 ret_from_fork+0x4bc/0x870 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 net_ratelimit: 17935 callbacks suppressed bridge0: received packet on veth0_to_bridge with own address as source address (addr:aa:aa:aa:aa:aa:0c, vlan:0) bridge0: received packet on veth0_to_bridge with own address as source address (addr:52:71:3c:b0:ae:a6, vlan:0) bridge0: received packet on bridge_slave_0 with own address as source address (addr:aa:aa:aa:aa:aa:1b, vlan:0) bridge0: received packet on veth0_to_bridge with own address as source address (addr:52:71:3c:b0:ae:a6, vlan:0) bridge0: received packet on bridge_slave_0 with own address as source address (addr:aa:aa:aa:aa:aa:0c, vlan:0) bridge0: received packet on veth0_to_bridge with own address as source address (addr:52:71:3c:b0:ae:a6, vlan:0) bridge0: received packet on veth0_to_bridge with own address as source address (addr:aa:aa:aa:aa:aa:0c, vlan:0) bridge0: received packet on veth0_to_bridge with own address as source address (addr:52:71:3c:b0:ae:a6, vlan:0) bridge0: received packet on bridge_slave_0 with own address as source address (addr:aa:aa:aa:aa:aa:0c, vlan:0) bridge0: received packet on veth0_to_bridge with own address as source address (addr:52:71:3c:b0:ae:a6, vlan:0) net_ratelimit: 19984 callbacks suppressed bridge0: received packet on bridge_slave_0 with own address as source address (addr:aa:aa:aa:aa:aa:0c, vlan:0) bridge0: received packet on veth0_to_bridge with own address as source address (addr:52:71:3c:b0:ae:a6, vlan:0) bridge0: received packet on bridge_slave_0 with own address as source address (addr:aa:aa:aa:aa:aa:0c, vlan:0) bridge0: received packet on veth0_to_bridge with own address as source address (addr:52:71:3c:b0:ae:a6, vlan:0) bridge0: received packet on veth0_to_bridge with own address as source address (addr:aa:aa:aa:aa:aa:0c, vlan:0) bridge0: received packet on veth0_to_bridge with own address as source address (addr:52:71:3c:b0:ae:a6, vlan:0) bridge0: received packet on veth0_to_bridge with own address as source address (addr:52:71:3c:b0:ae:a6, vlan:0) bridge0: received packet on veth0_to_bridge with own address as source address (addr:52:71:3c:b0:ae:a6, vlan:0) bridge0: received packet on bridge_slave_0 with own address as source address (addr:aa:aa:aa:aa:aa:0c, vlan:0) bridge0: received packet on veth0_to_bridge with own address as source address (addr:52:71:3c:b0:ae:a6, vlan:0)