bridge0: received packet on veth0_to_bridge with own address as source address (addr:ca:be:60:6d:00:e3, vlan:1) rcu: INFO: rcu_preempt detected stalls on CPUs/tasks: rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P4043/1:b..l rcu: (detected by 0, t=10503 jiffies, g=204253, q=3024 ncpus=2) task:syz-executor state:R running task stack:22280 pid:4043 tgid:4043 ppid:4032 task_flags:0x400140 flags:0x00080000 Call Trace: context_switch kernel/sched/core.c:5295 [inline] __schedule+0x15dd/0x52d0 kernel/sched/core.c:6908 preempt_schedule_irq+0x4d/0xa0 kernel/sched/core.c:7235 irqentry_exit+0x599/0x620 kernel/entry/common.c:239 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:697 RIP: 0010:lock_acquire+0x20b/0x2e0 kernel/locking/lockdep.c:5872 Code: e9 30 ff ff ff e8 35 79 0c 0a f7 c3 00 02 00 00 0f 84 38 ff ff ff 65 48 8b 05 b1 76 7a 11 48 3b 44 24 30 75 33 fb 48 83 c4 38 <5b> 41 5c 41 5d 41 5e 41 5f 5d e9 16 5f 0f 0a cc 48 8d 3d 6e 60 73 RSP: 0018:ffffc9000eba7338 EFLAGS: 00000282 RAX: f93bfab7b5350400 RBX: 0000000000000246 RCX: 0000000000000046 RDX: 00000000cdf111e1 RSI: ffffffff8e16642e RDI: ffffffff8c27b580 RBP: 0000000000000000 R08: ffffffff81767de5 R09: ffffffff8e75e420 R10: ffffc9000eba7498 R11: ffffffff81b0bfa0 R12: 0000000000000002 R13: ffffffff8e75e420 R14: 0000000000000000 R15: 0000000000000000 rcu_lock_acquire include/linux/rcupdate.h:312 [inline] rcu_read_lock include/linux/rcupdate.h:850 [inline] class_rcu_constructor include/linux/rcupdate.h:1193 [inline] unwind_next_frame+0xc2/0x23c0 arch/x86/kernel/unwind_orc.c:495 arch_stack_walk+0x11b/0x150 arch/x86/kernel/stacktrace.c:25 stack_trace_save+0xa9/0x100 kernel/stacktrace.c:122 save_stack+0x122/0x230 mm/page_owner.c:165 __reset_page_owner+0x71/0x1f0 mm/page_owner.c:320 reset_page_owner include/linux/page_owner.h:25 [inline] __free_pages_prepare mm/page_alloc.c:1433 [inline] __free_frozen_pages+0xc2b/0xdb0 mm/page_alloc.c:2978 __slab_free+0x263/0x2b0 mm/slub.c:5576 qlink_free mm/kasan/quarantine.c:163 [inline] qlist_free_all+0x97/0x100 mm/kasan/quarantine.c:179 kasan_quarantine_reduce+0x148/0x160 mm/kasan/quarantine.c:286 __kasan_kmalloc+0x22/0xb0 mm/kasan/common.c:406 kasan_kmalloc include/linux/kasan.h:263 [inline] __do_kmalloc_node mm/slub.c:5263 [inline] __kvmalloc_node_noprof+0x528/0x8a0 mm/slub.c:6755 alloc_fdtable+0x169/0x2c0 fs/file.c:224 dup_fd+0x84f/0xb40 fs/file.c:420 copy_files+0xc8/0x120 kernel/fork.c:1636 copy_process+0x175f/0x3cf0 kernel/fork.c:2211 kernel_clone+0x248/0x8e0 kernel/fork.c:2654 __do_sys_clone kernel/fork.c:2795 [inline] __se_sys_clone kernel/fork.c:2779 [inline] __x64_sys_clone+0x1b6/0x230 kernel/fork.c:2779 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0x14d/0xf80 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7fa1a49c5212 RSP: 002b:00007fffd7246920 EFLAGS: 00000246 ORIG_RAX: 0000000000000038 RAX: ffffffffffffffda RBX: 00007fffd7246920 RCX: 00007fa1a49c5212 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000001200011 RBP: 00007fffd7246aac R08: 0000000000000000 R09: 0000000000000001 R10: 00005555650b37d0 R11: 0000000000000246 R12: 0000000000000001 R13: 0000000000000030 R14: 0000000000111eba R15: 00007fffd7246b00 rcu: rcu_preempt kthread starved for 437 jiffies! g204253 f0x0 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:27696 pid:16 tgid:16 ppid:2 task_flags:0x208040 flags:0x00080000 Call Trace: context_switch kernel/sched/core.c:5295 [inline] __schedule+0x15dd/0x52d0 kernel/sched/core.c:6908 __schedule_loop kernel/sched/core.c:6990 [inline] schedule+0x164/0x360 kernel/sched/core.c:7005 schedule_timeout+0x158/0x2c0 kernel/time/sleep_timeout.c:99 rcu_gp_fqs_loop+0x312/0x11d0 kernel/rcu/tree.c:2095 rcu_gp_kthread+0x9e/0x2b0 kernel/rcu/tree.c:2297 kthread+0x388/0x470 kernel/kthread.c:436 ret_from_fork+0x51e/0xb90 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: 21585 Comm: kworker/u8:19 Not tainted syzkaller #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2026 Workqueue: events_unbound toggle_allocation_gate RIP: 0010:ip6_rcv_core+0x7b8/0x1740 net/ipv6/ip6_input.c:204 Code: 24 48 49 8b 45 00 65 4c 01 34 e8 48 c7 c7 40 54 eb 8c e8 ab f7 5d 01 48 b8 00 00 00 00 00 fc ff df 48 8b 4c 24 20 80 3c 01 00 <4c> 8b 2c 24 74 08 4c 89 ef e8 3a b2 df f7 49 8b 45 00 65 4c 01 34 RSP: 0018:ffffc90000a080d8 EFLAGS: 00000246 RAX: dffffc0000000000 RBX: ffff8880a6b348c0 RCX: 1ffff1100abcf099 RDX: ffff8880a6b3498c RSI: ffffffff8ceb5440 RDI: ffffffff8c27b580 RBP: 0000000000000004 R08: ffff8880a6b348ff R09: 0000000000000000 R10: ffff8880a6b348e8 R11: ffffed1014d66920 R12: ffff888091473000 R13: ffff8880914736f0 R14: 0000000000000001 R15: ffff888028503410 FS: 0000000000000000(0000) GS:ffff888125560000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007fca31c00218 CR3: 000000000e54c000 CR4: 00000000003526f0 Call Trace: ipv6_rcv+0x72/0xc0 net/ipv6/ip6_input.c:308 __netif_receive_skb_one_core net/core/dev.c:6164 [inline] __netif_receive_skb net/core/dev.c:6277 [inline] netif_receive_skb_internal net/core/dev.c:6363 [inline] netif_receive_skb+0x278/0xc50 net/core/dev.c:6422 NF_HOOK+0xa4/0x3a0 include/linux/netfilter.h:318 br_handle_frame_finish+0x14e2/0x1bb0 net/bridge/br_input.c:-1 br_nf_hook_thresh+0x3dd/0x4c0 net/bridge/br_netfilter_hooks.c:-1 br_nf_pre_routing_finish_ipv6+0xa3a/0xd70 net/bridge/br_netfilter_ipv6.c:-1 NF_HOOK include/linux/netfilter.h:318 [inline] br_nf_pre_routing_ipv6+0x374/0x6f0 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+0x1277/0x1510 net/bridge/br_input.c:442 __netif_receive_skb_core+0x98f/0x31a0 net/core/dev.c:6051 __netif_receive_skb_one_core net/core/dev.c:6162 [inline] __netif_receive_skb net/core/dev.c:6277 [inline] process_backlog+0x76d/0x1950 net/core/dev.c:6628 __napi_poll+0xae/0x340 net/core/dev.c:7692 napi_poll net/core/dev.c:7755 [inline] net_rx_action+0x627/0xf70 net/core/dev.c:7912 handle_softirqs+0x22a/0x870 kernel/softirq.c:622 __do_softirq kernel/softirq.c:656 [inline] invoke_softirq kernel/softirq.c:496 [inline] __irq_exit_rcu+0x5f/0x150 kernel/softirq.c:723 irq_exit_rcu+0x9/0x30 kernel/softirq.c:739 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1056 [inline] sysvec_apic_timer_interrupt+0xa6/0xc0 arch/x86/kernel/apic/apic.c:1056 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+0xcea/0x12c0 kernel/smp.c:877 Code: 89 ee 83 e6 01 31 ff e8 24 e6 0b 00 41 83 e5 01 49 bd 00 00 00 00 00 fc ff df 75 07 e8 cf e1 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 b3 e1 0b 00 eb e4 44 RSP: 0018:ffffc9000524f720 EFLAGS: 00000293 RAX: 0000000000000000 RBX: 1ffff110170c8515 RCX: ffff888058555b80 RDX: 0000000000000000 RSI: 0000000000000001 RDI: 0000000000000000 RBP: ffffc9000524f860 R08: ffffffff901196b7 R09: 1ffffffff20232d6 R10: dffffc0000000000 R11: fffffbfff20232d7 R12: ffff8880b86428a8 R13: dffffc0000000000 R14: ffff8880b873bf80 R15: 0000000000000000 on_each_cpu_cond_mask+0x3f/0x80 kernel/smp.c:1043 on_each_cpu include/linux/smp.h:72 [inline] smp_text_poke_sync_each_cpu arch/x86/kernel/alternative.c:2761 [inline] smp_text_poke_batch_finish+0x5f5/0x1160 arch/x86/kernel/alternative.c:2971 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:900 process_one_work kernel/workqueue.c:3275 [inline] process_scheduled_works+0xb02/0x1830 kernel/workqueue.c:3358 worker_thread+0xa50/0xfc0 kernel/workqueue.c:3439 kthread+0x388/0x470 kernel/kthread.c:436 ret_from_fork+0x51e/0xb90 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 net_ratelimit: 13570 callbacks suppressed bridge0: received packet on veth0_to_bridge with own address as source address (addr:ca:be:60:6d:00:e3, vlan:1) bridge0: received packet on veth0_to_bridge with own address as source address (addr:aa:aa:aa:aa:aa:0c, vlan:1) bridge0: received packet on bridge_slave_0 with own address as source address (addr:aa:aa:aa:aa:aa:1b, vlan:1) bridge0: received packet on bridge_slave_0 with own address as source address (addr:aa:aa:aa:aa:aa:0c, vlan:1) bridge0: received packet on veth0_to_bridge with own address as source address (addr:aa:aa:aa:aa:aa:0c, vlan:1) bridge0: received packet on veth0_to_bridge with own address as source address (addr:ca:be:60:6d:00:e3, vlan:1) bridge0: received packet on bridge_slave_0 with own address as source address (addr:aa:aa:aa:aa:aa:0c, vlan:1) bridge0: received packet on veth0_to_bridge with own address as source address (addr:aa:aa:aa:aa:aa:0c, vlan:1) bridge0: received packet on bridge_slave_0 with own address as source address (addr:aa:aa:aa:aa:aa:0c, vlan:1) bridge0: received packet on bridge_slave_0 with own address as source address (addr:aa:aa:aa:aa:aa:0c, vlan:1) net_ratelimit: 18809 callbacks suppressed bridge0: received packet on bridge_slave_0 with own address as source address (addr:aa:aa:aa:aa:aa:1b, vlan:1) bridge0: received packet on veth0_to_bridge with own address as source address (addr:aa:aa:aa:aa:aa:0c, vlan:1) bridge0: received packet on veth0_to_bridge with own address as source address (addr:aa:aa:aa:aa:aa:0c, vlan:1) bridge0: received packet on bridge_slave_0 with own address as source address (addr:aa:aa:aa:aa:aa:0c, vlan:1) bridge0: received packet on bridge_slave_0 with own address as source address (addr:aa:aa:aa:aa:aa:0c, vlan:1) bridge0: received packet on veth0_to_bridge with own address as source address (addr:ca:be:60:6d:00:e3, vlan:1) bridge0: received packet on bridge_slave_0 with own address as source address (addr:aa:aa:aa:aa:aa:0c, vlan:1) bridge0: received packet on veth0_to_bridge with own address as source address (addr:aa:aa:aa:aa:aa:0c, vlan:1) bridge0: received packet on veth0_to_bridge with own address as source address (addr:aa:aa:aa:aa:aa:0c, vlan:1) bridge0: received packet on bridge_slave_0 with own address as source address (addr:aa:aa:aa:aa:aa:0c, vlan:1)