bridge0: received packet on bridge_slave_1 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: (detected by 1, t=10718 jiffies, g=34733, q=1613 ncpus=2) rcu: All QSes seen, last rcu_preempt kthread activity 2670 (4294969561-4294966891), jiffies_till_next_fqs=1, root ->qsmask 0x0 rcu: rcu_preempt kthread starved for 2671 jiffies! g34733 f0x2 RCU_GP_WAIT_FQS(5) ->state=R ->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:17 tgid:17 ppid:2 task_flags:0x208040 flags:0x00080000 Call Trace: context_switch kernel/sched/core.c:5520 [inline] __schedule+0x17db/0x58f0 kernel/sched/core.c:7270 __schedule_loop kernel/sched/core.c:7347 [inline] schedule+0x164/0x2b0 kernel/sched/core.c:7362 schedule_timeout+0x152/0x2c0 kernel/time/sleep_timeout.c:99 rcu_gp_fqs_loop+0x30c/0x11f0 kernel/rcu/tree.c:2122 rcu_gp_kthread+0x9e/0x2b0 kernel/rcu/tree.c:2330 kthread+0x38b/0x480 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: 27 Comm: kworker/u8:2 Tainted: G L syzkaller #0 PREEMPT(full) Tainted: [L]=SOFTLOCKUP Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/24/2026 Workqueue: wg-kex-wg0 wg_packet_handshake_send_worker RIP: 0010:hlock_class kernel/locking/lockdep.c:234 [inline] RIP: 0010:lookup_chain_cache_add kernel/locking/lockdep.c:3836 [inline] RIP: 0010:validate_chain kernel/locking/lockdep.c:3892 [inline] RIP: 0010:__lock_acquire+0xaff/0x2e50 kernel/locking/lockdep.c:5254 Code: 00 00 48 09 dd 49 8b 46 20 89 c1 81 e1 00 80 04 00 81 f9 00 00 04 00 0f 85 49 02 00 00 25 ff 1f 00 00 48 0f a3 05 e1 0c f7 12 <72> 34 83 3d b8 9c fa 18 00 75 2b 90 e8 10 85 37 03 85 c0 74 1c 83 RSP: 0018:ffffc90000006170 EFLAGS: 00000007 RAX: 0000000000000071 RBX: 0000000073125dae RCX: 0000000000040000 RDX: 00000000001cee7d RSI: 000000009dc59b3c RDI: ffff88801e6f0000 RBP: bc101d9a73125dae R08: fb00000000000000 R09: 0000000000080000 R10: 0000000000000000 R11: ffff8880b8628298 R12: 0000000000000000 R13: 0000000000000000 R14: ffff88801e6f0cf0 R15: 0000000000000008 FS: 0000000000000000(0000) GS:ffff888124cd8000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00000000f0477000 CR3: 000000007e2a8000 CR4: 00000000003526f0 Call Trace: lock_acquire+0x115/0x350 kernel/locking/lockdep.c:5908 __raw_spin_lock_irq include/linux/spinlock_api_smp.h:165 [inline] _raw_spin_lock_irq+0x3d/0x50 kernel/locking/spinlock.c:189 __run_hrtimer kernel/time/hrtimer.c:2071 [inline] __hrtimer_run_queues+0x466/0xa10 kernel/time/hrtimer.c:2124 hrtimer_interrupt+0x4cd/0xaa0 kernel/time/hrtimer.c:2243 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1051 [inline] __sysvec_apic_timer_interrupt+0x102/0x430 arch/x86/kernel/apic/apic.c:1068 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1062 [inline] sysvec_apic_timer_interrupt+0x52/0xc0 arch/x86/kernel/apic/apic.c:1062 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:674 RIP: 0010:lock_acquire+0x232/0x350 kernel/locking/lockdep.c:5913 Code: ff ff ff e8 20 29 41 0a f7 44 24 10 00 02 00 00 0f 84 38 ff ff ff 65 48 8b 05 72 64 f1 11 48 3b 44 24 50 75 33 fb 48 83 c4 58 <5b> 41 5c 41 5d 41 5e 41 5f 5d e9 cf 2c 44 0a cc 48 8d 3d f7 32 da RSP: 0018:ffffc90000006660 EFLAGS: 00000296 RAX: 6d527a7c5ea93600 RBX: 0000000000000000 RCX: 8000000000000101 RDX: 000000004dbb4af1 RSI: ffffffff8e6fceb0 RDI: ffffffff8c6d9480 RBP: ffff88801e6f0000 R08: bb00000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: ffffffff8ed5c6e0 R12: ffffffff8ed5c6e0 R13: 0000000000000002 R14: 0000000000000000 R15: 0000000000000246 rcu_lock_acquire include/linux/rcupdate.h:309 [inline] rcu_read_lock include/linux/rcupdate.h:849 [inline] class_rcu_constructor include/linux/rcupdate.h:1216 [inline] unwind_next_frame+0xac/0x2550 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 kasan_save_stack mm/kasan/common.c:57 [inline] kasan_save_track+0x3e/0x80 mm/kasan/common.c:78 kasan_save_free_info+0x40/0x50 mm/kasan/generic.c:584 poison_slab_object mm/kasan/common.c:253 [inline] __kasan_slab_free+0x5c/0x80 mm/kasan/common.c:285 kasan_slab_free include/linux/kasan.h:235 [inline] slab_free_hook mm/slub.c:2748 [inline] slab_free mm/slub.c:6499 [inline] kmem_cache_free+0x182/0x650 mm/slub.c:6626 skb_ext_del include/linux/skbuff.h:5130 [inline] nf_bridge_info_free net/bridge/br_netfilter_hooks.c:157 [inline] br_nf_dev_queue_xmit+0x4f6/0x25c0 net/bridge/br_netfilter_hooks.c:856 NF_HOOK+0x64e/0x6e0 include/linux/netfilter.h:325 br_nf_post_routing+0xa53/0xee0 net/bridge/br_netfilter_hooks.c:964 nf_hook_entry_hookfn include/linux/netfilter.h:165 [inline] nf_hook_slow+0xc5/0x220 net/netfilter/core.c:619 nf_hook include/linux/netfilter.h:280 [inline] NF_HOOK+0x23e/0x3f0 include/linux/netfilter.h:323 br_forward_finish+0xd3/0x130 net/bridge/br_forward.c:66 br_nf_hook_thresh net/bridge/br_netfilter_hooks.c:1165 [inline] br_nf_forward_finish+0xa76/0xea0 net/bridge/br_netfilter_hooks.c:667 NF_HOOK+0x64e/0x6e0 include/linux/netfilter.h:325 br_nf_forward_ip+0x7eb/0xa30 net/bridge/br_netfilter_hooks.c:721 nf_hook_entry_hookfn include/linux/netfilter.h:165 [inline] nf_hook_slow+0xc5/0x220 net/netfilter/core.c:619 nf_hook include/linux/netfilter.h:280 [inline] NF_HOOK+0x23e/0x3f0 include/linux/netfilter.h:323 __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+0x3e6/0x8d0 net/bridge/br_forward.c:245 br_handle_frame_finish+0x1119/0x1950 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:325 [inline] br_nf_pre_routing_ipv6+0x382/0x6f0 net/bridge/br_netfilter_ipv6.c:183 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+0x989/0x30c0 net/core/dev.c:6151 __netif_receive_skb_one_core net/core/dev.c:6262 [inline] __netif_receive_skb net/core/dev.c:6377 [inline] process_backlog+0x727/0x18b0 net/core/dev.c:6728 __napi_poll+0xaa/0x330 net/core/dev.c:7787 napi_poll net/core/dev.c:7850 [inline] net_rx_action+0x61d/0xf50 net/core/dev.c:8007 handle_softirqs+0x226/0x860 kernel/softirq.c:645 do_softirq+0x77/0xd0 kernel/softirq.c:546 __local_bh_enable_ip+0x100/0x140 kernel/softirq.c:473 blake2s_compress+0xfa/0x1c00 lib/crypto/x86/blake2s.h:42 blake2s_final+0x10f/0x260 lib/crypto/blake2s.c:142 hmac+0x204/0x3b0 drivers/net/wireguard/noise.c:325 kdf+0x12d/0x290 drivers/net/wireguard/noise.c:367 mix_precomputed_dh drivers/net/wireguard/noise.c:426 [inline] wg_noise_handshake_create_initiation+0x460/0x810 drivers/net/wireguard/noise.c:560 wg_packet_send_handshake_initiation drivers/net/wireguard/send.c:34 [inline] wg_packet_handshake_send_worker+0x18c/0x370 drivers/net/wireguard/send.c:51 process_one_work kernel/workqueue.c:3396 [inline] process_scheduled_works+0xc3d/0x1630 kernel/workqueue.c:3479 worker_thread+0xa47/0xfb0 kernel/workqueue.c:3560 kthread+0x38b/0x480 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