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: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): P5986/1:b..l P5992/1:b..l rcu: (detected by 0, t=10502 jiffies, g=131913, q=650 ncpus=1) task:syz-executor state:R running task stack:21080 pid:5992 tgid:5992 ppid:5984 task_flags:0x400140 flags:0x00080000 Call Trace: context_switch kernel/sched/core.c:5260 [inline] __schedule+0x1138/0x5ee0 kernel/sched/core.c:6867 preempt_schedule_irq+0x51/0x90 kernel/sched/core.c:7194 irqentry_exit+0x1d8/0x8c0 kernel/entry/common.c:216 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:697 RIP: 0010:lock_acquire+0x62/0x330 kernel/locking/lockdep.c:5872 Code: 07 19 12 83 f8 07 0f 87 a2 02 00 00 89 c0 48 0f a3 05 b2 68 ef 0e 0f 82 74 02 00 00 8b 35 2a 99 ef 0e 85 f6 0f 85 8d 00 00 00 <48> 8b 44 24 30 65 48 2b 05 c9 06 19 12 0f 85 ad 02 00 00 48 83 c4 RSP: 0018:ffffc9000430f518 EFLAGS: 00000206 RAX: 0000000000000046 RBX: ffffffff8e3c94a0 RCX: 000000008f4abbda RDX: 0000000000000000 RSI: ffffffff8daa5e72 RDI: ffffffff8bf2b500 RBP: 0000000000000002 R08: 000000005999d6b8 R09: 0000000085999d6b R10: 0000000000000002 R11: ffff8880282da9b0 R12: 0000000000000000 R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000 rcu_lock_acquire include/linux/rcupdate.h:331 [inline] rcu_read_lock include/linux/rcupdate.h:867 [inline] class_rcu_constructor include/linux/rcupdate.h:1195 [inline] unwind_next_frame+0xd1/0x20b0 arch/x86/kernel/unwind_orc.c:495 arch_stack_walk+0x94/0x100 arch/x86/kernel/stacktrace.c:25 stack_trace_save+0x8e/0xc0 kernel/stacktrace.c:122 save_stack+0x160/0x1f0 mm/page_owner.c:165 __reset_page_owner+0x84/0x1a0 mm/page_owner.c:320 reset_page_owner include/linux/page_owner.h:25 [inline] free_pages_prepare mm/page_alloc.c:1433 [inline] __free_frozen_pages+0x7df/0x1170 mm/page_alloc.c:2973 discard_slab mm/slub.c:3346 [inline] __put_partials+0x130/0x170 mm/slub.c:3886 qlink_free mm/kasan/quarantine.c:163 [inline] qlist_free_all+0x4c/0xf0 mm/kasan/quarantine.c:179 kasan_quarantine_reduce+0x195/0x1e0 mm/kasan/quarantine.c:286 __kasan_slab_alloc+0x69/0x90 mm/kasan/common.c:350 kasan_slab_alloc include/linux/kasan.h:253 [inline] slab_post_alloc_hook mm/slub.c:4953 [inline] slab_alloc_node mm/slub.c:5263 [inline] kmem_cache_alloc_noprof+0x25e/0x770 mm/slub.c:5270 lsm_file_alloc security/security.c:169 [inline] security_file_alloc+0x34/0x2b0 security/security.c:2380 init_file+0x93/0x4c0 fs/file_table.c:159 alloc_empty_file+0x73/0x1e0 fs/file_table.c:241 path_openat+0xde/0x3140 fs/namei.c:4782 do_filp_open+0x20b/0x470 fs/namei.c:4823 do_sys_openat2+0x121/0x290 fs/open.c:1430 do_sys_open fs/open.c:1436 [inline] __do_sys_openat fs/open.c:1452 [inline] __se_sys_openat fs/open.c:1447 [inline] __x64_sys_openat+0x174/0x210 fs/open.c:1447 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xcd/0xf80 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f1685f8f0c1 RSP: 002b:00007ffd99e06140 EFLAGS: 00000287 ORIG_RAX: 0000000000000101 RAX: ffffffffffffffda RBX: 00007f1686013d7d RCX: 00007f1685f8f0c1 RDX: 0000000000090800 RSI: 00007ffd99e072f0 RDI: 00000000ffffff9c RBP: 00007ffd99e072dc R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000287 R12: 00007ffd99e072f0 R13: 00007f1686013d7d R14: 00000000000b2be6 R15: 00007ffd99e07330 task:syz-executor state:R running task stack:23720 pid:5986 tgid:5986 ppid:1 task_flags:0x40054c flags:0x00080003 Call Trace: context_switch kernel/sched/core.c:5260 [inline] __schedule+0x1138/0x5ee0 kernel/sched/core.c:6867 preempt_schedule_common+0x44/0xc0 kernel/sched/core.c:7051 preempt_schedule_thunk+0x16/0x30 arch/x86/entry/thunk.S:12 __raw_read_unlock include/linux/rwlock_api_smp.h:233 [inline] _raw_read_unlock+0x3e/0x50 kernel/locking/spinlock.c:260 zap_pid_ns_processes+0x26a/0x6d0 kernel/pid_namespace.c:233 find_child_reaper kernel/exit.c:622 [inline] forget_original_parent kernel/exit.c:706 [inline] exit_notify kernel/exit.c:743 [inline] do_exit+0x2476/0x2bd0 kernel/exit.c:983 do_group_exit+0xd3/0x2a0 kernel/exit.c:1112 get_signal+0x2671/0x26d0 kernel/signal.c:3034 arch_do_signal_or_restart+0x8f/0x7a0 arch/x86/kernel/signal.c:337 __exit_to_user_mode_loop kernel/entry/common.c:41 [inline] exit_to_user_mode_loop+0x8c/0x540 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+0x4ee/0xf80 arch/x86/entry/syscall_64.c:100 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f2928f8deba RSP: 002b:00007fffe594aa98 EFLAGS: 00000286 ORIG_RAX: 0000000000000106 RAX: 0000000000000000 RBX: 00007f2929013d7d RCX: 00007f2928f8deba RDX: 00007fffe594aac0 RSI: 00007fffe594ab50 RDI: 00000000ffffff9c RBP: 00007fffe594ab50 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000100 R11: 0000000000000286 R12: 00007fffe594bbe0 R13: 00007f2929013d7d R14: 00000000000b2bd8 R15: 00007fffe594bc20 rcu: rcu_preempt kthread starved for 287 jiffies! g131913 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:27672 pid:16 tgid:16 ppid:2 task_flags:0x208040 flags:0x00080000 Call Trace: context_switch kernel/sched/core.c:5260 [inline] __schedule+0x1138/0x5ee0 kernel/sched/core.c:6867 __schedule_loop kernel/sched/core.c:6949 [inline] schedule+0xe7/0x3a0 kernel/sched/core.c:6964 schedule_timeout+0x123/0x290 kernel/time/sleep_timeout.c:99 rcu_gp_fqs_loop+0x1ea/0xaf0 kernel/rcu/tree.c:2083 rcu_gp_kthread+0x26d/0x380 kernel/rcu/tree.c:2285 kthread+0x3c5/0x780 kernel/kthread.c:463 ret_from_fork+0x983/0xb10 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: CPU: 0 UID: 0 PID: 17046 Comm: kworker/u11:8 Tainted: G U I L syzkaller #0 PREEMPT(full) Tainted: [U]=USER, [I]=FIRMWARE_WORKAROUND, [L]=SOFTLOCKUP Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/13/2026 Workqueue: events_unbound nsim_dev_trap_report_work RIP: 0010:nf_hook_bridge_pre net/bridge/br_input.c:296 [inline] RIP: 0010:br_handle_frame+0xb57/0x14e0 net/bridge/br_input.c:442 Code: d7 8c 0f b6 f8 89 44 24 08 89 3c 24 e8 c2 9e 7a f7 8b 04 24 83 f8 01 0f 84 99 02 00 00 83 f8 03 0f 84 c5 01 00 00 85 c0 74 0c <31> db e8 a2 a3 7a f7 e9 42 fa ff ff e8 98 a3 7a f7 ba 02 00 00 00 RSP: 0018:ffffc90000007878 EFLAGS: 00000292 RAX: 0000000000000000 RBX: ffff88807c4b6000 RCX: ffffffff89471ab9 RDX: ffff888030351e80 RSI: ffffffff8a43ad2a RDI: 0000000000000001 RBP: ffff8881620b98c0 R08: 0000000000000001 R09: 0000000000000000 R10: 0000000000000001 R11: 0000000000002ba1 R12: ffff888067052338 R13: ffffc900000078e0 R14: 0000000000000003 R15: dffffc0000000000 FS: 0000000000000000(0000) GS:ffff8881248f6000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f5a07f12157 CR3: 00000000786a2000 CR4: 00000000003526f0 Call Trace: __netif_receive_skb_core.constprop.0+0x6b3/0x35b0 net/core/dev.c:6039 __netif_receive_skb_one_core+0xb0/0x1e0 net/core/dev.c:6150 __netif_receive_skb+0x1d/0x160 net/core/dev.c:6265 process_backlog+0x4ab/0x1650 net/core/dev.c:6617 __napi_poll.constprop.0+0xb3/0x540 net/core/dev.c:7681 napi_poll net/core/dev.c:7744 [inline] net_rx_action+0x9f9/0xfa0 net/core/dev.c:7896 handle_softirqs+0x219/0x950 kernel/softirq.c:622 do_softirq kernel/softirq.c:523 [inline] do_softirq+0xb2/0xf0 kernel/softirq.c:510 __local_bh_enable_ip+0x100/0x120 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+0x8b5/0xcf0 drivers/net/netdevsim/dev.c:921 process_one_work+0x9ba/0x1b20 kernel/workqueue.c:3257 process_scheduled_works kernel/workqueue.c:3340 [inline] worker_thread+0x6c8/0xf10 kernel/workqueue.c:3421 kthread+0x3c5/0x780 kernel/kthread.c:463 ret_from_fork+0x983/0xb10 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:246 net_ratelimit: 32908 callbacks suppressed 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: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: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: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: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:aa:aa:aa:aa:aa:0c, vlan:0) net_ratelimit: 45398 callbacks suppressed 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: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: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: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: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:aa:aa:aa:aa:aa:0c, vlan:0)