bridge0: received packet on veth0_to_bridge with own address as source address (addr:fe:33:aa:61:93:3b, vlan:0) rcu: INFO: rcu_preempt detected stalls on CPUs/tasks: rcu: (detected by 1, t=10502 jiffies, g=281861, q=1608 ncpus=2) rcu: All QSes seen, last rcu_preempt kthread activity 7539 (4295103832-4295096293), jiffies_till_next_fqs=1, root ->qsmask 0x0 rcu: rcu_preempt kthread starved for 7540 jiffies! g281861 f0x2 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:26848 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: 2345 Comm: kworker/R-bond1 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: 0x0 (bond1) RIP: 0010:check_preemption_disabled+0x1/0xe0 lib/smp_processor_id.c:13 Code: 20 dc 4b 8c 48 c7 c6 60 dc 4b 8c eb 1c 66 66 66 2e 0f 1f 84 00 00 00 00 00 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 55 <41> 57 41 56 53 65 8b 05 77 ad 99 07 65 8b 0d 6c ad 99 07 f7 c1 ff RSP: 0018:ffffc90000006bd0 EFLAGS: 00000092 RAX: 0000000000000001 RBX: 0000000000000000 RCX: 0000000000000000 RDX: 00000000a42637f2 RSI: ffffffff8e4b3e80 RDI: ffffffff8c4bdc80 RBP: ffffffff8177827f R08: ffffffff8177827f R09: 0000000000000000 R10: 0000000000000000 R11: ffffffff8eb59d60 R12: 0000000000000002 R13: ffffffff8eb59d60 R14: 0000000000000000 R15: 0000000000000246 FS: 0000000000000000(0000) GS:ffff888124f3f000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f94abf429ec CR3: 0000000058434000 CR4: 00000000003526f0 DR0: ffffffffffffffff DR1: 00000000000001f8 DR2: 0000000000000002 DR3: ffffffffefffff15 DR6: 00000000ffff0ff0 DR7: 0000000000000400 Call Trace: lockdep_recursion_finish kernel/locking/lockdep.c:470 [inline] lock_acquire+0x116/0x350 kernel/locking/lockdep.c:5870 rcu_lock_acquire include/linux/rcupdate.h:300 [inline] rcu_read_lock include/linux/rcupdate.h:840 [inline] class_rcu_constructor include/linux/rcupdate.h:1183 [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 unpoison_slab_object mm/kasan/common.c:340 [inline] __kasan_slab_alloc+0x6c/0x80 mm/kasan/common.c:366 kasan_slab_alloc include/linux/kasan.h:253 [inline] slab_post_alloc_hook mm/slub.c:4584 [inline] slab_alloc_node mm/slub.c:4917 [inline] kmem_cache_alloc_noprof+0x2a0/0x5f0 mm/slub.c:4931 skb_ext_maybe_cow net/core/skbuff.c:7118 [inline] skb_ext_add+0x1b6/0x8e0 net/core/skbuff.c:7193 nf_bridge_unshare net/bridge/br_netfilter_hooks.c:170 [inline] br_nf_forward_ip+0xc3/0xa30 net/bridge/br_netfilter_hooks.c:686 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:6103 __netif_receive_skb_one_core net/core/dev.c:6214 [inline] __netif_receive_skb net/core/dev.c:6329 [inline] process_backlog+0x706/0x1860 net/core/dev.c:6680 __napi_poll+0xaa/0x330 net/core/dev.c:7739 napi_poll net/core/dev.c:7802 [inline] net_rx_action+0x61d/0xf50 net/core/dev.c:7959 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:__raw_spin_unlock_irq include/linux/spinlock_api_smp.h:188 [inline] RIP: 0010:_raw_spin_unlock_irq+0x29/0x50 kernel/locking/spinlock.c:206 Code: 90 f3 0f 1e fa 53 48 89 fb 48 83 c7 18 48 8b 74 24 08 e8 ca e7 cb f5 48 89 df e8 22 5d cc f5 e8 cd 3d f8 f5 fb bf 01 00 00 00 d2 70 bd f5 65 8b 05 8b 0f 97 07 85 c0 74 07 5b c3 cc cc cc cc RSP: 0018:ffffc9000389fce0 EFLAGS: 00000206 RAX: 000000000053bc63 RBX: ffff88801b0cb000 RCX: 0000000080000001 RDX: 0000000000000000 RSI: ffffffff8e22f03a RDI: 0000000000000001 RBP: dffffc0000000000 R08: ffffffff90579f37 R09: 1ffffffff20af3e6 R10: dffffc0000000000 R11: fffffbfff20af3e7 R12: ffff888054b76f68 R13: ffff88801b0cb060 R14: ffff8880331d58e0 R15: ffff88807efd7638 rescuer_thread+0xd77/0x10b0 kernel/workqueue.c:3663 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