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): P32374/1:b..l rcu: (detected by 1, t=10503 jiffies, g=243857, q=826 ncpus=2) task:syz.8.6287 state:R running task stack:23656 pid:32374 tgid:32367 ppid:27628 task_flags:0x40054c flags:0x00080001 Call Trace: context_switch kernel/sched/core.c:5256 [inline] __schedule+0x14bc/0x5000 kernel/sched/core.c:6863 preempt_schedule_irq+0xb5/0x150 kernel/sched/core.c:7190 irqentry_exit+0x5d8/0x660 kernel/entry/common.c:216 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:697 RIP: 0010:deref_stack_reg arch/x86/kernel/unwind_orc.c:406 [inline] RIP: 0010:unwind_next_frame+0xc61/0x2390 arch/x86/kernel/unwind_orc.c:585 Code: e8 84 23 00 00 48 89 c3 48 bd 00 00 00 00 00 fc ff df 48 8b 44 24 30 80 3c 28 00 4c 8b 7c 24 18 74 08 4c 89 ff e8 5f b8 b3 00 <49> 89 1f 48 8b 44 24 58 80 3c 28 00 48 8b 5c 24 70 4c 8b 6c 24 50 RSP: 0018:ffffc90005276b58 EFLAGS: 00000246 RAX: 1ffff92000a4ed8e RBX: ffffffff81ab7937 RCX: 1ffff92000a4ed01 RDX: ffffffff9012fece RSI: 0000000000000002 RDI: ffffc90005277e80 RBP: dffffc0000000000 R08: 0000000000000007 R09: ffffffff8df419e0 R10: ffffc90005276c78 R11: ffffffff81ad9fb0 R12: ffffc90005278000 R13: 1ffff92000a4ed87 R14: ffffc90005276c28 R15: ffffc90005276c70 arch_stack_walk+0x11c/0x150 arch/x86/kernel/stacktrace.c:25 stack_trace_save+0x9c/0xe0 kernel/stacktrace.c:122 save_stack+0xf5/0x1f0 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:1395 [inline] free_unref_folios+0xdb3/0x14f0 mm/page_alloc.c:3000 folios_put_refs+0x584/0x670 mm/swap.c:1002 free_pages_and_swap_cache+0x277/0x520 mm/swap_state.c:355 __tlb_batch_free_encoded_pages mm/mmu_gather.c:136 [inline] tlb_batch_pages_flush mm/mmu_gather.c:149 [inline] tlb_flush_mmu_free mm/mmu_gather.c:397 [inline] tlb_flush_mmu+0x3a0/0x680 mm/mmu_gather.c:404 zap_pte_range mm/memory.c:1893 [inline] zap_pmd_range mm/memory.c:1946 [inline] zap_pud_range mm/memory.c:1975 [inline] zap_p4d_range mm/memory.c:1996 [inline] unmap_page_range+0x3962/0x4170 mm/memory.c:2017 unmap_single_vma mm/memory.c:2059 [inline] unmap_vmas+0x399/0x580 mm/memory.c:2101 exit_mmap+0x239/0xb10 mm/mmap.c:1277 __mmput+0x118/0x430 kernel/fork.c:1173 exit_mm+0x1da/0x2c0 kernel/exit.c:581 do_exit+0x658/0x2310 kernel/exit.c:959 do_group_exit+0x21c/0x2d0 kernel/exit.c:1112 get_signal+0x1285/0x1340 kernel/signal.c:3034 arch_do_signal_or_restart+0x9a/0x7a0 arch/x86/kernel/signal.c:337 __exit_to_user_mode_loop kernel/entry/common.c:41 [inline] exit_to_user_mode_loop+0x87/0x4f0 kernel/entry/common.c:75 __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_work include/linux/entry-common.h:159 [inline] syscall_exit_to_user_mode include/linux/entry-common.h:194 [inline] do_syscall_64+0x2e3/0xf80 arch/x86/entry/syscall_64.c:100 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f32d218f749 RSP: 002b:00007f32d03f6038 EFLAGS: 00000246 ORIG_RAX: 000000000000002e RAX: 0000000000000048 RBX: 00007f32d23e6180 RCX: 00007f32d218f749 RDX: 0000000000000000 RSI: 0000200000000280 RDI: 0000000000000010 RBP: 00007f32d2213f91 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007f32d23e6218 R14: 00007f32d23e6180 R15: 00007f32d250fa28 rcu: rcu_preempt kthread starved for 2929 jiffies! g243857 f0x0 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:27136 pid:16 tgid:16 ppid:2 task_flags:0x208040 flags:0x00080000 Call Trace: context_switch kernel/sched/core.c:5256 [inline] __schedule+0x14bc/0x5000 kernel/sched/core.c:6863 __schedule_loop kernel/sched/core.c:6945 [inline] schedule+0x165/0x360 kernel/sched/core.c:6960 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+0x599/0xb30 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:246 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: 1316 Comm: kworker/u8:9 Tainted: G L syzkaller #0 PREEMPT(full) Tainted: [L]=SOFTLOCKUP Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025 Workqueue: events_unbound nsim_dev_trap_report_work RIP: 0010:unwind_next_frame+0xc6d/0x2390 arch/x86/kernel/unwind_orc.c:590 Code: 00 00 00 fc ff df 48 8b 44 24 30 80 3c 28 00 4c 8b 7c 24 18 74 08 4c 89 ff e8 5f b8 b3 00 49 89 1f 48 8b 44 24 58 80 3c 28 00 <48> 8b 5c 24 70 4c 8b 6c 24 50 4c 8b 64 24 10 74 08 48 89 df e8 3a RSP: 0018:ffffc90000006858 EFLAGS: 00000246 RAX: 1ffff92000000d2c RBX: ffffffff8a391a56 RCX: 1ffff92000000d01 RDX: ffffffff90a760e6 RSI: 0000000000000002 RDI: ffffc90000007418 RBP: dffffc0000000000 R08: 0000000000000001 R09: ffffffff8df419e0 R10: ffffc90000006978 R11: ffffffff81ad9fb0 R12: ffffc90000008000 R13: 1ffff92000000d27 R14: ffffc90000006928 R15: ffffc90000006970 FS: 0000000000000000(0000) GS:ffff888125e44000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00002000003f5030 CR3: 0000000076312000 CR4: 00000000003526f0 Call Trace: arch_stack_walk+0x11c/0x150 arch/x86/kernel/stacktrace.c:25 stack_trace_save+0x9c/0xe0 kernel/stacktrace.c:122 kasan_save_stack mm/kasan/common.c:56 [inline] kasan_save_track+0x3e/0x80 mm/kasan/common.c:77 kasan_save_free_info+0x46/0x50 mm/kasan/generic.c:584 poison_slab_object mm/kasan/common.c:252 [inline] __kasan_slab_free+0x5c/0x80 mm/kasan/common.c:284 kasan_slab_free include/linux/kasan.h:234 [inline] slab_free_hook mm/slub.c:2540 [inline] slab_free mm/slub.c:6663 [inline] kmem_cache_free+0x197/0x620 mm/slub.c:6774 skb_ext_reset include/linux/skbuff.h:5074 [inline] skb_release_head_state+0x270/0x360 net/core/skbuff.c:1174 skb_release_all net/core/skbuff.c:1180 [inline] __kfree_skb net/core/skbuff.c:1196 [inline] sk_skb_reason_drop+0xe9/0x170 net/core/skbuff.c:1234 kfree_skb_reason include/linux/skbuff.h:1322 [inline] kfree_skb include/linux/skbuff.h:1331 [inline] ip6_mc_input+0x8de/0xb70 net/ipv6/ip6_input.c:593 ip_sabotage_in+0x1e1/0x270 net/bridge/br_netfilter_hooks.c:990 nf_hook_entry_hookfn include/linux/netfilter.h:158 [inline] nf_hook_slow+0xc5/0x220 net/netfilter/core.c:623 nf_hook include/linux/netfilter.h:273 [inline] NF_HOOK+0x206/0x3a0 include/linux/netfilter.h:316 __netif_receive_skb_one_core net/core/dev.c:6137 [inline] __netif_receive_skb+0xd3/0x380 net/core/dev.c:6250 netif_receive_skb_internal net/core/dev.c:6336 [inline] netif_receive_skb+0x1bb/0x750 net/core/dev.c:6395 NF_HOOK+0xa0/0x390 include/linux/netfilter.h:319 br_handle_frame_finish+0x15c6/0x1c90 net/bridge/br_input.c:235 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+0x95f/0x2f90 net/core/dev.c:6024 __netif_receive_skb_one_core net/core/dev.c:6135 [inline] __netif_receive_skb+0x72/0x380 net/core/dev.c:6250 process_backlog+0x622/0x1500 net/core/dev.c:6602 __napi_poll+0xae/0x320 net/core/dev.c:7666 napi_poll net/core/dev.c:7729 [inline] net_rx_action+0x672/0xe50 net/core/dev.c:7881 handle_softirqs+0x27d/0x850 kernel/softirq.c:622 do_softirq+0xec/0x180 kernel/softirq.c:523 __local_bh_enable_ip+0x17d/0x1c0 kernel/softirq.c:450 spin_unlock_bh include/linux/spinlock.h:396 [inline] nsim_dev_trap_report drivers/net/netdevsim/dev.c:890 [inline] nsim_dev_trap_report_work+0x7c7/0xb80 drivers/net/netdevsim/dev.c:921 process_one_work kernel/workqueue.c:3257 [inline] process_scheduled_works+0xad1/0x1770 kernel/workqueue.c:3340 worker_thread+0x8a0/0xda0 kernel/workqueue.c:3421 kthread+0x711/0x8a0 kernel/kthread.c:463 ret_from_fork+0x599/0xb30 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:246 net_ratelimit: 15620 callbacks suppressed 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:1b, vlan:0) bridge0: received packet on veth0_to_bridge with own address as source address (addr:86:bc:de:b1:3d:f4, vlan:0) bridge0: received packet on bridge_slave_0 with own address as source address (addr:aa:aa:aa:aa:aa:1b, vlan:0) bridge0: received packet on veth0_to_bridge with own address as source address (addr:86:bc:de:b1:3d:f4, vlan:0) bridge0: received packet on bridge_slave_0 with own address as source address (addr:aa:aa:aa:aa:aa:1b, 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 bridge_slave_0 with own address as source address (addr:aa:aa:aa:aa:aa:1b, 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 bridge_slave_0 with own address as source address (addr:aa:aa:aa:aa:aa:1b, vlan:0)