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: Tasks blocked on level-0 rcu_node (CPUs 0-1): P17783/1:b..l rcu: (detected by 0, t=10503 jiffies, g=112521, q=1331 ncpus=2) task:syz-executor state:R running task stack:22376 pid:17783 tgid:17783 ppid:1 task_flags:0x40054c flags:0x00080002 Call Trace: context_switch kernel/sched/core.c:5388 [inline] __schedule+0x1821/0x5740 kernel/sched/core.c:7189 preempt_schedule_irq+0x4d/0xa0 kernel/sched/core.c:7513 irqentry_exit_to_kernel_mode include/linux/irq-entry-common.h:539 [inline] irqentry_exit+0x14f/0x760 kernel/entry/common.c:164 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:697 RIP: 0010:lock_acquire+0x221/0x350 kernel/locking/lockdep.c:5872 Code: ff ff ff e8 f1 8d 07 0a f7 44 24 08 00 02 00 00 0f 84 3a ff ff ff 65 48 8b 05 db d8 97 11 48 3b 44 24 58 75 33 fb 48 83 c4 60 <5b> 41 5c 41 5d 41 5e 41 5f 5d e9 40 81 0a 0a cc 48 8d 3d 88 7b 92 RSP: 0018:ffffc90003def1f8 EFLAGS: 00000282 RAX: c8fce3420fbc9800 RBX: 0000000000000000 RCX: 0000000000000046 RDX: 00000000ae0c93a7 RSI: ffffffff8e2203c4 RDI: ffffffff8c28b660 RBP: ffffffff8176f256 R08: ffffffff8176f256 R09: ffffffff8e95cca0 R10: ffffc90003def368 R11: fffff520007bde79 R12: 0000000000000002 R13: ffffffff8e95cca0 R14: 0000000000000000 R15: 0000000000000246 rcu_lock_acquire include/linux/rcupdate.h:300 [inline] rcu_read_lock include/linux/rcupdate.h:838 [inline] class_rcu_constructor include/linux/rcupdate.h:1181 [inline] unwind_next_frame+0xc3/0x2550 arch/x86/kernel/unwind_orc.c:495 __unwind_start+0x5b8/0x760 arch/x86/kernel/unwind_orc.c:787 unwind_start arch/x86/include/asm/unwind.h:64 [inline] arch_stack_walk+0xe3/0x150 arch/x86/kernel/stacktrace.c:24 stack_trace_save+0xa9/0x100 kernel/stacktrace.c:122 kasan_save_stack+0x3e/0x60 mm/kasan/common.c:57 kasan_record_aux_stack+0xbd/0xd0 mm/kasan/generic.c:556 __call_rcu_common kernel/rcu/tree.c:3131 [inline] call_rcu+0xee/0x890 kernel/rcu/tree.c:3251 slab_free_hook mm/slub.c:2653 [inline] slab_free mm/slub.c:6250 [inline] kmem_cache_free+0x462/0x650 mm/slub.c:6377 tear_down_vmas+0x312/0x520 mm/mmap.c:1262 exit_mmap+0x4b6/0x9e0 mm/mmap.c:1320 __mmput+0x118/0x430 kernel/fork.c:1178 exit_mm+0x1f6/0x2d0 kernel/exit.c:582 do_exit+0x6a2/0x22c0 kernel/exit.c:964 do_group_exit+0x21b/0x2d0 kernel/exit.c:1119 get_signal+0x1284/0x1330 kernel/signal.c:3037 arch_do_signal_or_restart+0xbc/0x840 arch/x86/kernel/signal.c:337 __exit_to_user_mode_loop kernel/entry/common.c:64 [inline] exit_to_user_mode_loop+0x8c/0x4d0 kernel/entry/common.c:98 __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+0x33e/0xf80 arch/x86/entry/syscall_64.c:100 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7fd32b55d68e RSP: 002b:00007ffc0632c868 EFLAGS: 00000246 ORIG_RAX: 00000000000000e6 RAX: 0000000000000000 RBX: 000055556779c500 RCX: 00007fd32b55d68e RDX: 00007ffc0632c8c0 RSI: 0000000000000000 RDI: 0000000000000000 RBP: 00007ffc0632c92c R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00000000000000fc R13: 000000000000005e R14: 0000000000081dad R15: 00007ffc0632c980 rcu: rcu_preempt kthread starved for 3888 jiffies! g112521 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:27688 pid:16 tgid:16 ppid:2 task_flags:0x208040 flags:0x00080000 Call Trace: context_switch kernel/sched/core.c:5388 [inline] __schedule+0x1821/0x5740 kernel/sched/core.c:7189 __schedule_loop kernel/sched/core.c:7268 [inline] schedule+0x164/0x360 kernel/sched/core.c:7283 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+0x389/0x470 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 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 UID: 0 PID: 12144 Comm: kworker/u8:21 Not tainted syzkaller #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/18/2026 Workqueue: wg-kex-wg0 wg_packet_handshake_send_worker RIP: 0010:check_kcov_mode kernel/kcov.c:194 [inline] RIP: 0010:__sanitizer_cov_trace_pc+0x36/0x70 kernel/kcov.c:217 Code: 38 cb 73 11 65 8b 15 59 cb 73 11 81 e2 00 01 ff 00 74 11 81 fa 00 01 00 00 75 35 83 b9 d4 16 00 00 00 74 2c 8b 91 b0 16 00 00 <83> fa 02 75 21 48 8b 91 b8 16 00 00 48 8b 32 48 8d 7e 01 8b 89 b4 RSP: 0018:ffffc9000393f590 EFLAGS: 00000246 RAX: ffffffff8a575312 RBX: ffff888036bbe040 RCX: ffff888031b38000 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000002 RBP: 0000000000000000 R08: ffff888036bbe043 R09: 1ffff11006d77c08 R10: dffffc0000000000 R11: ffffed1006d77c09 R12: ffff888036f70578 R13: ffff888036bbe000 R14: ffff888036f70846 R15: ffffc9000393f840 FS: 0000000000000000(0000) GS:ffff888125387000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000561ed69c5000 CR3: 000000007632c000 CR4: 00000000003526f0 Call Trace: rcuref_get include/linux/rcuref.h:87 [inline] dst_hold_safe include/net/dst.h:311 [inline] ip6_route_output_flags+0x3d2/0x5d0 net/ipv6/route.c:2718 ip6_route_output include/net/ip6_route.h:100 [inline] ip6_dst_lookup_tail+0x1c3/0x15a0 net/ipv6/ip6_output.c:1158 ip6_dst_lookup_flow+0x89/0x150 net/ipv6/ip6_output.c:1291 send6+0x4dc/0x910 drivers/net/wireguard/socket.c:139 wg_socket_send_skb_to_peer+0x111/0x1d0 drivers/net/wireguard/socket.c:177 wg_packet_send_handshake_initiation drivers/net/wireguard/send.c:40 [inline] wg_packet_handshake_send_worker+0x203/0x350 drivers/net/wireguard/send.c:51 process_one_work kernel/workqueue.c:3314 [inline] process_scheduled_works+0xb5d/0x1860 kernel/workqueue.c:3397 worker_thread+0xa53/0xfc0 kernel/workqueue.c:3478 kthread+0x389/0x470 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: 17684 callbacks suppressed bridge0: received packet on bridge_slave_1 with own address as source address (addr:aa:aa:aa:aa:aa:1c, vlan:0) bridge0: received packet on veth1_to_bridge with own address as source address (addr:aa:aa:aa:aa:aa:0c, vlan:0) bridge0: received packet on veth1_to_bridge with own address as source address (addr:22:c4:1e:3e:fd:22, vlan:0) bridge0: received packet on veth1_to_bridge with own address as source address (addr:aa:aa:aa:aa:aa:0c, vlan:0) bridge0: received packet on bridge_slave_1 with own address as source address (addr:aa:aa:aa:aa:aa:1c, vlan:0) bridge0: received packet on bridge_slave_1 with own address as source address (addr:aa:aa:aa:aa:aa:0c, vlan:0) bridge0: received packet on veth1_to_bridge with own address as source address (addr:22:c4:1e:3e:fd:22, vlan:0) bridge0: received packet on bridge_slave_1 with own address as source address (addr:aa:aa:aa:aa:aa:0c, vlan:0) bridge0: received packet on bridge_slave_1 with own address as source address (addr:aa:aa:aa:aa:aa:1c, vlan:0) bridge0: received packet on veth1_to_bridge with own address as source address (addr:aa:aa:aa:aa:aa:0c, vlan:0) net_ratelimit: 18638 callbacks suppressed bridge0: received packet on veth1_to_bridge with own address as source address (addr:22:c4:1e:3e:fd:22, vlan:0) bridge0: received packet on veth1_to_bridge with own address as source address (addr:aa:aa:aa:aa:aa:0c, vlan:0) bridge0: received packet on bridge_slave_1 with own address as source address (addr:aa:aa:aa:aa:aa:1c, vlan:0) bridge0: received packet on bridge_slave_1 with own address as source address (addr:aa:aa:aa:aa:aa:0c, vlan:0) bridge0: received packet on veth1_to_bridge with own address as source address (addr:22:c4:1e:3e:fd:22, vlan:0) bridge0: received packet on bridge_slave_1 with own address as source address (addr:aa:aa:aa:aa:aa:0c, vlan:0) bridge0: received packet on bridge_slave_1 with own address as source address (addr:aa:aa:aa:aa:aa:1c, vlan:0) bridge0: received packet on veth1_to_bridge with own address as source address (addr:aa:aa:aa:aa:aa:0c, vlan:0) bridge0: received packet on veth1_to_bridge with own address as source address (addr:22:c4:1e:3e:fd:22, vlan:0) bridge0: received packet on veth1_to_bridge with own address as source address (addr:aa:aa:aa:aa:aa:0c, vlan:0)