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): P18478/1:b..l rcu: (detected by 1, t=10502 jiffies, g=63941, q=2573 ncpus=2) task:syz.5.3509 state:R running task stack:28872 pid:18478 tgid:18474 ppid:17693 task_flags:0x400040 flags:0x00080002 Call Trace: context_switch kernel/sched/core.c:5325 [inline] __schedule+0x1798/0x4cc0 kernel/sched/core.c:6929 preempt_schedule_irq+0xb5/0x150 kernel/sched/core.c:7256 irqentry_exit+0x6f/0x90 kernel/entry/common.c:211 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:697 RIP: 0010:on_stack arch/x86/include/asm/stacktrace.h:56 [inline] RIP: 0010:unwind_next_frame+0x1831/0x2390 arch/x86/kernel/unwind_orc.c:665 Code: 58 80 3c 28 00 74 05 e8 dd 23 b2 00 4d 8b 66 38 49 8d 7e 08 48 89 f8 48 c1 e8 03 80 3c 28 00 74 05 e8 c3 23 b2 00 4d 8b 6e 08 <4d> 8d 7e 10 4c 89 f8 48 c1 e8 03 80 3c 28 00 74 08 4c 89 ff e8 a6 RSP: 0018:ffffc9000b8af838 EFLAGS: 00000246 RAX: 1ffff92001715f22 RBX: ffffc9000b8af901 RCX: 0000000000000000 RDX: ffffffff90184494 RSI: 0000000000000000 RDI: ffffc9000b8af910 RBP: dffffc0000000000 R08: ffffc9000b8af967 R09: 0000000000000000 R10: ffffc9000b8af958 R11: fffff52001715f2d R12: ffffc9000b8afd18 R13: ffffc9000b8a8000 R14: ffffc9000b8af908 R15: ffffffff81738c45 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:156 __reset_page_owner+0x71/0x1f0 mm/page_owner.c:311 reset_page_owner include/linux/page_owner.h:25 [inline] free_pages_prepare mm/page_alloc.c:1394 [inline] __free_frozen_pages+0xbc4/0xd30 mm/page_alloc.c:2901 __slab_free+0x2e7/0x390 mm/slub.c:5970 qlink_free mm/kasan/quarantine.c:163 [inline] qlist_free_all+0x97/0x140 mm/kasan/quarantine.c:179 kasan_quarantine_reduce+0x148/0x160 mm/kasan/quarantine.c:286 __kasan_slab_alloc+0x22/0x80 mm/kasan/common.c:352 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_lru_noprof+0x35d/0x6d0 mm/slub.c:5307 sock_alloc_inode+0x28/0xc0 net/socket.c:322 alloc_inode+0x6a/0x1b0 fs/inode.c:346 new_inode_pseudo include/linux/fs.h:3397 [inline] sock_alloc net/socket.c:637 [inline] __sock_create+0x12d/0x9f0 net/socket.c:1569 sock_create net/socket.c:1663 [inline] __sys_socket_create net/socket.c:1700 [inline] __sys_socket+0xd7/0x1b0 net/socket.c:1747 __do_sys_socket net/socket.c:1761 [inline] __se_sys_socket net/socket.c:1759 [inline] __x64_sys_socket+0x7a/0x90 net/socket.c:1759 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xfa/0xfa0 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7eff8ab8f749 RSP: 002b:00007eff8ba2e038 EFLAGS: 00000246 ORIG_RAX: 0000000000000029 RAX: ffffffffffffffda RBX: 00007eff8ade6090 RCX: 00007eff8ab8f749 RDX: 000000000000000c RSI: 0000000000000003 RDI: 0000000000000010 RBP: 00007eff8ac13f91 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007eff8ade6128 R14: 00007eff8ade6090 R15: 00007fffaf41da18 rcu: rcu_preempt kthread starved for 334 jiffies! g63941 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: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: Sending NMI from CPU 1 to CPUs 0: NMI backtrace for cpu 0 CPU: 0 UID: 0 PID: 8501 Comm: kworker/u8:46 Not tainted syzkaller #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025 Workqueue: events_unbound toggle_allocation_gate RIP: 0010:hlock_class kernel/locking/lockdep.c:234 [inline] RIP: 0010:__lock_acquire+0x893/0xd20 kernel/locking/lockdep.c:5233 Code: 83 3d d4 c6 df 0d 00 0f 85 36 02 00 00 48 83 7c 24 28 00 0f 84 bc 01 00 00 41 8b 46 f8 25 ff 1f 00 00 48 0f a3 05 dd d5 d8 11 <0f> 83 5a 01 00 00 48 69 c0 c8 00 00 00 48 8d 80 30 33 17 93 e9 87 RSP: 0018:ffffc90000006888 EFLAGS: 00000003 RAX: 0000000000000007 RBX: 0000000000000007 RCX: 000000006290c103 RDX: 00000000071bee9f RSI: 00000000a42637f2 RDI: ffff88806dd71e40 RBP: 0000000000000000 R08: 0000000000000000 R09: ffffffff81738c45 R10: ffffc90000006ad8 R11: ffffffff81ac2e10 R12: 000000000afe4109 R13: ffff88806dd72970 R14: ffff88806dd72a88 R15: 39529a686290c103 FS: 0000000000000000(0000) GS:ffff888126138000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007ffed99ed9bc CR3: 000000000dd38000 CR4: 00000000003526f0 Call Trace: lock_acquire+0x120/0x360 kernel/locking/lockdep.c:5868 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+0xc2/0x2390 arch/x86/kernel/unwind_orc.c:479 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 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_noprof+0x367/0x6e0 mm/slub.c:5295 skb_ext_maybe_cow net/core/skbuff.c:7000 [inline] skb_ext_add+0x1b6/0x8f0 net/core/skbuff.c:7075 nf_bridge_unshare net/bridge/br_netfilter_hooks.c:169 [inline] br_nf_forward_ip+0xc6/0x7e0 net/bridge/br_netfilter_hooks.c:681 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+0x215/0x3c0 include/linux/netfilter.h:316 __br_forward+0x41e/0x600 net/bridge/br_forward.c:115 br_handle_frame_finish+0x15a3/0x1c90 net/bridge/br_input.c:229 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:csd_lock_wait kernel/smp.c:342 [inline] RIP: 0010:smp_call_function_many_cond+0xd33/0x12d0 kernel/smp.c:877 Code: 45 8b 2c 24 44 89 ee 83 e6 01 31 ff e8 e6 73 0b 00 41 83 e5 01 49 bd 00 00 00 00 00 fc ff df 75 07 e8 91 6f 0b 00 eb 38 f3 90 <42> 0f b6 04 2b 84 c0 75 11 41 f7 04 24 01 00 00 00 74 1e e8 75 6f RSP: 0018:ffffc900030b7640 EFLAGS: 00000293 RAX: ffffffff81b4943b RBX: 1ffff11017127ffd RCX: ffff88806dd71e40 RDX: 0000000000000000 RSI: 0000000000000001 RDI: 0000000000000000 RBP: ffffc900030b77c0 R08: ffffffff8f7cf477 R09: 1ffffffff1ef9e8e R10: dffffc0000000000 R11: fffffbfff1ef9e8f R12: ffff8880b893ffe8 R13: dffffc0000000000 R14: ffff8880b883b240 R15: 0000000000000001 on_each_cpu_cond_mask+0x3f/0x80 kernel/smp.c:1043 on_each_cpu include/linux/smp.h:71 [inline] smp_text_poke_sync_each_cpu arch/x86/kernel/alternative.c:2713 [inline] smp_text_poke_batch_finish+0x5f9/0x1130 arch/x86/kernel/alternative.c:2923 arch_jump_label_transform_apply+0x1c/0x30 arch/x86/kernel/jump_label.c:146 static_key_enable_cpuslocked+0x128/0x250 kernel/jump_label.c:210 static_key_enable+0x1a/0x20 kernel/jump_label.c:223 toggle_allocation_gate+0xad/0x240 mm/kfence/core.c:852 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 net_ratelimit: 8875 callbacks suppressed bridge0: received packet on veth0_to_bridge with own address as source address (addr:c2:bc:2c:23:9f:a8, 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: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 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:c2:bc:2c:23:9f:a8, 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) net_ratelimit: 10306 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: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 veth0_to_bridge with own address as source address (addr:c2:bc:2c:23:9f:a8, 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:c2:bc:2c:23:9f:a8, 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:c2:bc:2c:23:9f:a8, vlan:0) bridge0: received packet on bridge_slave_0 with own address as source address (addr:aa:aa:aa:aa:aa:0c, vlan:0)