bridge0: received packet on veth0_to_bridge with own address as source address (addr:aa:aa:aa:aa:aa:0c, vlan:0) rcu: INFO: rcu_preempt detected stalls on CPUs/tasks: rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P11681/1:b..l rcu: (detected by 1, t=10502 jiffies, g=377377, q=958 ncpus=2) task:syz.3.10608 state:R running task stack:26440 pid:11681 tgid:11677 ppid:6438 task_flags:0x40044c flags:0x00080003 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 65 b8 0c 0a f7 c3 00 02 00 00 0f 84 38 ff ff ff 65 48 8b 05 e1 75 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 46 9e 0f 0a cc 48 8d 3d 9e 61 73 RSP: 0018:ffffc9000c8d7518 EFLAGS: 00000286 RAX: 5341cc63a84c0f00 RBX: 0000000000000246 RCX: 0000000000000046 RDX: 000000005a44979c RSI: ffffffff8e16704b RDI: ffffffff8c27bd00 RBP: 0000000000000000 R08: ffffffff81767de5 R09: ffffffff8e75e420 R10: ffffc9000c8d7678 R11: ffffffff81b0c070 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 vfree+0x25a/0x400 mm/vmalloc.c:3479 kcov_put kernel/kcov.c:442 [inline] kcov_close+0x28/0x50 kernel/kcov.c:543 __fput+0x44f/0xa70 fs/file_table.c:469 task_work_run+0x1d9/0x270 kernel/task_work.c:233 exit_task_work include/linux/task_work.h:40 [inline] do_exit+0x70f/0x23c0 kernel/exit.c:976 do_group_exit+0x21b/0x2d0 kernel/exit.c:1118 get_signal+0x1284/0x1330 kernel/signal.c:3034 arch_do_signal_or_restart+0xbc/0x830 arch/x86/kernel/signal.c:337 __exit_to_user_mode_loop kernel/entry/common.c:64 [inline] exit_to_user_mode_loop+0x86/0x480 kernel/entry/common.c:98 __exit_to_user_mode_prepare include/linux/irq-entry-common.h:226 [inline] syscall_exit_to_user_mode_prepare include/linux/irq-entry-common.h:256 [inline] syscall_exit_to_user_mode include/linux/entry-common.h:325 [inline] do_syscall_64+0x32d/0xf80 arch/x86/entry/syscall_64.c:100 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f3184f9c799 RSP: 002b:00007f31831ac028 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: ffffffffffffff9e RBX: 00007f3185216180 RCX: 00007f3184f9c799 RDX: 0000200000000100 RSI: 0000000000003ba0 RDI: 0000000000000006 RBP: 00007f3185032c99 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007f3185216218 R14: 00007f3185216180 R15: 00007f318533fa48 rcu: rcu_preempt kthread starved for 669 jiffies! g377377 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:27616 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: CPU: 1 UID: 0 PID: 19384 Comm: kworker/u8:1 Tainted: G L syzkaller #0 PREEMPT(full) Tainted: [L]=SOFTLOCKUP Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2026 Workqueue: wg-kex-wg2 wg_packet_handshake_send_worker 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 fc 66 26 0a 65 66 8b 05 6c 09 94 11 66 85 c0 75 32 bf 01 00 00 00 e8 a5 f4 0b 00 e8 90 8e 45 00 fb 65 8b 05 48 09 94 11 <85> c0 75 05 e8 ff b6 ab ff 5b 41 5e c3 cc cc cc cc cc 90 0f 0b 90 RSP: 0018:ffffc90000a07fc8 EFLAGS: 00000202 RAX: 0000000080000101 RBX: 0000000000000200 RCX: 0000000080000101 RDX: 0000000000000002 RSI: ffffffff8def6335 RDI: ffffffff8c27bd00 RBP: ffffc90000a08298 R08: ffffffff901198b7 R09: 1ffffffff2023316 R10: dffffc0000000000 R11: fffffbfff2023317 R12: 1ffff9200014101c R13: ffff888076c51000 R14: ffffffff897cc427 R15: 0000000100000000 FS: 0000000000000000(0000) GS:ffff888125560000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007ff8e120e9a3 CR3: 0000000026c78000 CR4: 00000000003526f0 Call Trace: local_bh_enable include/linux/bottom_half.h:33 [inline] rcu_read_unlock_bh include/linux/rcupdate.h:924 [inline] __dev_queue_xmit+0x1e78/0x3890 net/core/dev.c:4873 dev_queue_xmit include/linux/netdevice.h:3384 [inline] br_dev_queue_push_xmit+0x370/0x4a0 net/bridge/br_forward.c:53 NF_HOOK+0x360/0x3f0 include/linux/netfilter.h:318 br_forward_finish+0xd3/0x130 net/bridge/br_forward.c:66 NF_HOOK+0x360/0x3f0 include/linux/netfilter.h:318 __br_forward+0x397/0x540 net/bridge/br_forward.c:115 deliver_clone net/bridge/br_forward.c:131 [inline] maybe_deliver net/bridge/br_forward.c:191 [inline] br_flood+0x6ee/0xb80 net/bridge/br_forward.c:238 br_handle_frame_finish+0x14c2/0x1bb0 net/bridge/br_input.c:229 nf_hook_bridge_pre net/bridge/br_input.c:313 [inline] br_handle_frame+0x80f/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+0x76/0xd0 kernel/softirq.c:523 __local_bh_enable_ip+0xf8/0x130 kernel/softirq.c:450 blake2s_compress+0xf9/0x1eb0 lib/crypto/x86/blake2s.h:42 blake2s_update+0x14b/0x450 lib/crypto/blake2s.c:119 hmac+0x1fc/0x3b0 drivers/net/wireguard/noise.c:324 kdf+0xff/0x2b0 drivers/net/wireguard/noise.c:360 mix_precomputed_dh drivers/net/wireguard/noise.c:426 [inline] wg_noise_handshake_create_initiation+0x473/0x830 drivers/net/wireguard/noise.c:560 wg_packet_send_handshake_initiation drivers/net/wireguard/send.c:34 [inline] wg_packet_handshake_send_worker+0x18d/0x350 drivers/net/wireguard/send.c:51 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 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:aa:aa:aa:aa:aa:0c, 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:aa:aa:aa:aa:aa:0c, vlan:0)