bridge0: received packet on veth0_to_bridge with own address as source address (addr:b2:80:6a:9d:5f:59, vlan:0) 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): P5822/1:b..l rcu: (detected by 1, t=10503 jiffies, g=28069, q=1291 ncpus=2) task:syz-executor state:R running task stack:21256 pid:5822 tgid:5822 ppid:1 task_flags:0x40054c flags:0x00080002 Call Trace: context_switch kernel/sched/core.c:5325 [inline] __schedule+0x1798/0x4cc0 kernel/sched/core.c:6929 preempt_schedule_common+0x83/0xd0 kernel/sched/core.c:7113 preempt_schedule+0xae/0xc0 kernel/sched/core.c:7137 preempt_schedule_thunk+0x16/0x30 arch/x86/entry/thunk.S:12 __raw_spin_unlock include/linux/spinlock_api_smp.h:143 [inline] _raw_spin_unlock+0x3f/0x50 kernel/locking/spinlock.c:186 spin_unlock include/linux/spinlock.h:391 [inline] zap_pte_range mm/memory.c:1885 [inline] zap_pmd_range mm/memory.c:1947 [inline] zap_pud_range mm/memory.c:1976 [inline] zap_p4d_range mm/memory.c:1997 [inline] unmap_page_range+0x3a7f/0x4370 mm/memory.c:2018 unmap_single_vma mm/memory.c:2061 [inline] unmap_vmas+0x399/0x580 mm/memory.c:2105 exit_mmap+0x240/0xb40 mm/mmap.c:1280 __mmput+0x118/0x430 kernel/fork.c:1133 exit_mm+0x1da/0x2c0 kernel/exit.c:582 do_exit+0x648/0x2300 kernel/exit.c:954 do_group_exit+0x21c/0x2d0 kernel/exit.c:1107 get_signal+0x1285/0x1340 kernel/signal.c:3034 arch_do_signal_or_restart+0xa0/0x790 arch/x86/kernel/signal.c:337 exit_to_user_mode_loop+0x72/0x130 kernel/entry/common.c:40 exit_to_user_mode_prepare include/linux/irq-entry-common.h:225 [inline] syscall_exit_to_user_mode_work include/linux/entry-common.h:175 [inline] syscall_exit_to_user_mode include/linux/entry-common.h:210 [inline] do_syscall_64+0x2bd/0xfa0 arch/x86/entry/syscall_64.c:100 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7fbf475c1f85 RSP: 002b:00007ffda9fd30e0 EFLAGS: 00000293 ORIG_RAX: 00000000000000e6 RAX: 0000000000000000 RBX: 000000000000030f RCX: 00007fbf475c1f85 RDX: 00007ffda9fd3120 RSI: 0000000000000000 RDI: 0000000000000000 RBP: 00007ffda9fd318c R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000293 R12: 0000000000000107 R13: 0000000000000060 R14: 0000000000029be8 R15: 00007ffda9fd31e0 rcu: rcu_preempt kthread starved for 542 jiffies! g28069 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:27224 pid:16 tgid:16 ppid:2 task_flags:0x208040 flags:0x00080000 Call Trace: context_switch kernel/sched/core.c:5325 [inline] __schedule+0x1798/0x4cc0 kernel/sched/core.c:6929 __schedule_loop kernel/sched/core.c:7011 [inline] schedule+0x165/0x360 kernel/sched/core.c:7026 schedule_timeout+0x12b/0x270 kernel/time/sleep_timeout.c:99 rcu_gp_fqs_loop+0x301/0x1540 kernel/rcu/tree.c:2083 rcu_gp_kthread+0x99/0x390 kernel/rcu/tree.c:2285 kthread+0x711/0x8a0 kernel/kthread.c:463 ret_from_fork+0x4bc/0x870 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: 8807 Comm: kworker/u8:25 Not tainted syzkaller #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025 Workqueue: events_unbound nsim_dev_trap_report_work RIP: 0010:console_trylock_spinning kernel/printk/printk.c:2034 [inline] RIP: 0010:vprintk_emit+0x49d/0x590 kernel/printk/printk.c:2422 Code: 0f 84 34 ff ff ff e8 c2 eb 1f 00 fb eb 44 e8 ba eb 1f 00 e8 f5 39 a6 09 4d 85 f6 74 94 e8 ab eb 1f 00 fb 48 c7 c7 80 16 f3 8d <31> f6 ba 01 00 00 00 31 c9 41 b8 01 00 00 00 45 31 c9 53 e8 0b 39 RSP: 0018:ffffc90000a07ec0 EFLAGS: 00000246 RAX: ffffffff81a01825 RBX: ffffffff81a0167e RCX: ffff888024ee5ac0 RDX: 0000000000000100 RSI: 0000000000000000 RDI: ffffffff8df31680 RBP: ffffc90000a07fd0 R08: ffffffff8f7ce877 R09: 1ffffffff1ef9d0e R10: dffffc0000000000 R11: fffffbfff1ef9d0f R12: 0000000000000000 R13: 000000000000006f R14: 0000000000000200 R15: 1ffff92000140fdc FS: 0000000000000000(0000) GS:ffff88812623b000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f6d025156e8 CR3: 000000000dd38000 CR4: 00000000003526f0 Call Trace: _printk+0xcf/0x120 kernel/printk/printk.c:2448 br_fdb_update+0x62d/0x690 net/bridge/br_fdb.c:999 br_handle_frame_finish+0x587/0x1c90 net/bridge/br_input.c:144 br_nf_hook_thresh+0x3c6/0x4a0 net/bridge/br_netfilter_hooks.c:-1 br_nf_pre_routing_finish_ipv6+0x999/0xd60 net/bridge/br_netfilter_ipv6.c:-1 NF_HOOK include/linux/netfilter.h:318 [inline] br_nf_pre_routing_ipv6+0x37e/0x6b0 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+0x96e/0x14f0 net/bridge/br_input.c:442 __netif_receive_skb_core+0x10b9/0x4380 net/core/dev.c:5966 __netif_receive_skb_one_core net/core/dev.c:6077 [inline] __netif_receive_skb+0x72/0x380 net/core/dev.c:6192 process_backlog+0x60e/0x14f0 net/core/dev.c:6544 __napi_poll+0xc7/0x360 net/core/dev.c:7594 napi_poll net/core/dev.c:7657 [inline] net_rx_action+0x5f7/0xdf0 net/core/dev.c:7784 handle_softirqs+0x286/0x870 kernel/softirq.c:622 __do_softirq kernel/softirq.c:656 [inline] invoke_softirq kernel/softirq.c:496 [inline] __irq_exit_rcu+0xca/0x1f0 kernel/softirq.c:723 irq_exit_rcu+0x9/0x30 kernel/softirq.c:739 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1052 [inline] sysvec_apic_timer_interrupt+0xa6/0xc0 arch/x86/kernel/apic/apic.c:1052 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:697 RIP: 0010:find_stack lib/stackdepot.c:601 [inline] RIP: 0010:stack_depot_save_flags+0x163/0x860 lib/stackdepot.c:668 Code: c8 31 c5 c1 c0 18 29 c5 48 8b 05 58 83 ec 14 8b 0d 4a 83 ec 14 21 e9 48 c1 e1 04 4c 8d 24 08 65 ff 05 21 da ac 0d 4c 8b 3c 08 <4d> 39 e7 44 89 2c 24 74 05 45 89 d5 eb 34 45 31 ff e9 85 00 00 00 RSP: 0018:ffffc9000567f5e8 EFLAGS: 00000282 RAX: ffff88823ae00000 RBX: 0000000000000801 RCX: 0000000000b1ac10 RDX: 0000000047b9b8b0 RSI: 0000000000000001 RDI: 000000001510bc65 RBP: 000000004a6b1ac1 R08: 0000000027081c4e R09: 00000000fd305855 R10: 000000000000000a R11: ffffffff81ac2ea0 R12: ffff88823b91ac10 R13: 0000000000000820 R14: ffffc9000567f650 R15: ffff88805d5e68c0 kasan_save_stack mm/kasan/common.c:57 [inline] kasan_save_track+0x4f/0x80 mm/kasan/common.c:77 unpoison_slab_object mm/kasan/common.c:342 [inline] __kasan_slab_alloc+0x6c/0x80 mm/kasan/common.c:368 kasan_slab_alloc include/linux/kasan.h:252 [inline] slab_post_alloc_hook mm/slub.c:4978 [inline] slab_alloc_node mm/slub.c:5288 [inline] kmem_cache_alloc_node_noprof+0x433/0x710 mm/slub.c:5340 __alloc_skb+0x112/0x2d0 net/core/skbuff.c:660 alloc_skb include/linux/skbuff.h:1383 [inline] nsim_dev_trap_skb_build drivers/net/netdevsim/dev.c:763 [inline] nsim_dev_trap_report drivers/net/netdevsim/dev.c:820 [inline] nsim_dev_trap_report_work+0x29a/0xb80 drivers/net/netdevsim/dev.c:866 process_one_work kernel/workqueue.c:3263 [inline] process_scheduled_works+0xae1/0x17b0 kernel/workqueue.c:3346 worker_thread+0x8a0/0xda0 kernel/workqueue.c:3427 kthread+0x711/0x8a0 kernel/kthread.c:463 ret_from_fork+0x4bc/0x870 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 bridge0: received packet on veth0_to_bridge with own address as source address (addr:b2:80:6a:9d:5f:59, 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:b2:80:6a:9d:5f:59, 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 veth0_to_bridge with own address as source address (addr:aa:aa:aa:aa:aa:0c, vlan:0)