bridge0: received packet on veth0_to_bridge with own address as source address (addr:6e:4e:a4:52:df:fc, vlan:0) rcu: INFO: rcu_preempt detected stalls on CPUs/tasks: rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P21570/1:b..l rcu: (detected by 1, t=10503 jiffies, g=437325, q=7941 ncpus=2) task:syz.0.21225 state:R running task stack:26920 pid:21570 tgid:21570 ppid:5643 task_flags:0x40044c flags:0x00080002 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 include/linux/spinlock_api_smp.h:169 [inline] _raw_spin_unlock+0x3f/0x50 kernel/locking/spinlock.c:190 spin_unlock include/linux/spinlock.h:390 [inline] zap_pte_range mm/memory.c:1964 [inline] zap_pmd_range mm/memory.c:2020 [inline] zap_pud_range mm/memory.c:2048 [inline] zap_p4d_range mm/memory.c:2069 [inline] __zap_vma_range+0x4084/0x4f10 mm/memory.c:2109 unmap_vmas+0x390/0x550 mm/memory.c:2178 exit_mmap+0x293/0x9f0 mm/mmap.c:1300 __mmput+0x118/0x420 kernel/fork.c:1182 exit_mm+0x221/0x2d0 kernel/exit.c:610 do_exit+0x6cd/0x2360 kernel/exit.c:992 do_group_exit+0x22d/0x2f0 kernel/exit.c:1147 get_signal+0x121b/0x12c0 kernel/signal.c:3038 arch_do_signal_or_restart+0xbb/0x860 arch/x86/kernel/signal.c:337 __exit_to_user_mode_loop kernel/entry/common.c:66 [inline] exit_to_user_mode_loop+0x104/0x730 kernel/entry/common.c:101 __exit_to_user_mode_prepare include/linux/irq-entry-common.h:207 [inline] syscall_exit_to_user_mode_prepare include/linux/irq-entry-common.h:230 [inline] syscall_exit_to_user_mode include/linux/entry-common.h:318 [inline] do_syscall_64+0x353/0x580 arch/x86/entry/syscall_64.c:100 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f828195d68e RSP: 002b:00007f828291df58 EFLAGS: 00000246 ORIG_RAX: 00000000000000e6 RAX: fffffffffffffdfc RBX: 00007f828291e6c0 RCX: 00007f828195d68e RDX: 00007f828291dfb0 RSI: 0000000000000000 RDI: 0000000000000000 RBP: 00007f8281a32e6f R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007f8281c16038 R14: 00007f8281c15fa0 R15: 00007f8281d3fa48 rcu: rcu_preempt kthread starved for 595 jiffies! g437325 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:27496 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 1 to CPUs 0: NMI backtrace for cpu 0 CPU: 0 UID: 0 PID: 30457 Comm: kworker/u8:30 Tainted: G L syzkaller #0 PREEMPT(full) Tainted: [L]=SOFTLOCKUP Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/09/2026 Workqueue: events_unbound toggle_allocation_gate RIP: 0010:ifname_compare_aligned include/linux/netfilter/x_tables.h:425 [inline] RIP: 0010:ip6_packet_match net/ipv6/netfilter/ip6_tables.c:65 [inline] RIP: 0010:ip6t_do_table+0x669/0x15b0 net/ipv6/netfilter/ip6_tables.c:306 Code: b6 d8 31 ff 89 de e8 06 ef 4e f7 84 db 0f 94 c0 44 30 f0 0f 84 24 03 00 00 48 8b 4c 24 60 48 89 c8 48 c1 e8 03 42 80 3c 28 00 <74> 0f 48 8b 7c 24 60 e8 7b 70 bc f7 48 8b 4c 24 60 49 8d 5c 24 40 RSP: 0018:ffffc90000006d20 EFLAGS: 00000246 RAX: 1ffff1100fd47024 RBX: 0000000000000000 RCX: ffff88807ea38120 RDX: ffff888030cbbe00 RSI: 0000000000000000 RDI: 0000000000000000 RBP: ffffc90000006f10 R08: ffffc90000006e8f R09: 0000000000000000 R10: ffffc90000006e70 R11: fffff52000000dd2 R12: ffff8880347ed1e0 R13: dffffc0000000000 R14: 0000000000000000 R15: ffff8880347ed218 FS: 0000000000000000(0000) GS:ffff888125220000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f8145c00218 CR3: 000000000e746000 CR4: 00000000003526f0 DR0: 0000000000000004 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000600 Call Trace: ip6table_mangle_hook+0x2b8/0x730 net/ipv6/netfilter/ip6table_mangle.c:73 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+0x560/0x6e0 include/linux/netfilter.h:316 br_nf_forward_ip+0x7eb/0xa30 net/bridge/br_netfilter_hooks.c:721 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+0x23e/0x3f0 include/linux/netfilter.h:316 __br_forward+0x397/0x540 net/bridge/br_forward.c:115 br_handle_frame_finish+0x1175/0x1990 net/bridge/br_input.c:229 br_nf_hook_thresh+0x3dd/0x4c0 net/bridge/br_netfilter_hooks.c:-1 br_nf_pre_routing_finish_ipv6+0x90c/0xc40 net/bridge/br_netfilter_ipv6.c:-1 NF_HOOK include/linux/netfilter.h:318 [inline] br_nf_pre_routing_ipv6+0x382/0x6f0 net/bridge/br_netfilter_ipv6.c:183 nf_hook_entry_hookfn include/linux/netfilter.h:158 [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:6093 __netif_receive_skb_one_core net/core/dev.c:6204 [inline] __netif_receive_skb net/core/dev.c:6319 [inline] process_backlog+0x706/0x1860 net/core/dev.c:6670 __napi_poll+0xaa/0x330 net/core/dev.c:7729 napi_poll net/core/dev.c:7792 [inline] net_rx_action+0x61d/0xf50 net/core/dev.c:7949 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:csd_lock_wait kernel/smp.c:342 [inline] RIP: 0010:smp_call_function_many_cond+0x10b5/0x14b0 kernel/smp.c:892 Code: 1e 89 de 83 e6 01 31 ff e8 d8 1e 0c 00 83 e3 01 48 bb 00 00 00 00 00 fc ff df 75 07 e8 84 1a 0c 00 eb 37 f3 90 41 0f b6 04 1c <84> c0 75 10 41 f7 06 01 00 00 00 74 1e e8 69 1a 0c 00 eb e5 44 89 RSP: 0018:ffffc900053df720 EFLAGS: 00000293 RAX: 0000000000000000 RBX: dffffc0000000000 RCX: ffff888030cbbe00 RDX: 0000000000000000 RSI: 0000000000000001 RDI: 0000000000000000 RBP: ffffc900053df860 R08: ffffffff9032f8f7 R09: 1ffffffff2065f1e R10: dffffc0000000000 R11: fffffbfff2065f1f R12: 1ffff110170e81d1 R13: ffff8880b863c448 R14: ffff8880b8740e88 R15: 0000000000000001 on_each_cpu_cond_mask+0x3f/0x80 kernel/smp.c:1057 on_each_cpu include/linux/smp.h:72 [inline] smp_text_poke_sync_each_cpu arch/x86/kernel/alternative.c:2773 [inline] smp_text_poke_batch_finish+0x5fd/0x1110 arch/x86/kernel/alternative.c:2983 arch_jump_label_transform_apply+0x1c/0x30 arch/x86/kernel/jump_label.c:146 static_key_enable_cpuslocked+0x128/0x240 kernel/jump_label.c:210 static_key_enable+0x1a/0x20 kernel/jump_label.c:223 toggle_allocation_gate+0xab/0x290 mm/kfence/core.c:911 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 net_ratelimit: 22177 callbacks suppressed bridge0: received packet on veth0_to_bridge with own address as source address (addr:6e:4e:a4:52:df:fc, vlan:0) bridge0: received packet on veth0_to_bridge with own address as source address (addr:6e:4e:a4:52:df:fc, vlan:0) bridge0: received packet on veth0_to_bridge with own address as source address (addr:6e:4e:a4:52:df:fc, vlan:0) bridge0: received packet on veth0_to_bridge with own address as source address (addr:6e:4e:a4:52:df:fc, vlan:0) bridge0: received packet on veth0_to_bridge with own address as source address (addr:6e:4e:a4:52:df:fc, 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:6e:4e:a4:52:df:fc, 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:6e:4e:a4:52:df:fc, vlan:0) bridge0: received packet on veth0_to_bridge with own address as source address (addr:6e:4e:a4:52:df:fc, vlan:0) net_ratelimit: 27328 callbacks suppressed bridge0: received packet on veth0_to_bridge with own address as source address (addr:6e:4e:a4:52:df:fc, vlan:0) bridge0: received packet on veth0_to_bridge with own address as source address (addr:6e:4e:a4:52:df:fc, 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:6e:4e:a4:52:df:fc, 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:6e:4e:a4:52:df:fc, vlan:0) bridge0: received packet on veth0_to_bridge with own address as source address (addr:6e:4e:a4:52:df:fc, vlan:0) bridge0: received packet on veth0_to_bridge with own address as source address (addr:6e:4e:a4:52:df:fc, 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:6e:4e:a4:52:df:fc, vlan:0)