bridge0: received packet on bridge_slave_0 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): P6483/1:b..l rcu: (detected by 0, t=10502 jiffies, g=10573, q=420 ncpus=2) task:syz-executor state:R running task stack:25512 pid:6483 tgid:6483 ppid:5834 task_flags:0x400000 flags:0x00004002 Call Trace: context_switch kernel/sched/core.c:5357 [inline] __schedule+0x1190/0x5de0 kernel/sched/core.c:6961 preempt_schedule_irq+0x51/0x90 kernel/sched/core.c:7288 irqentry_exit+0x36/0x90 kernel/entry/common.c:197 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702 RIP: 0010:lock_acquire+0x62/0x350 kernel/locking/lockdep.c:5872 Code: 06 3f 12 83 f8 07 0f 87 bc 02 00 00 89 c0 48 0f a3 05 22 99 13 0f 0f 82 74 02 00 00 8b 35 da ca 13 0f 85 f6 0f 85 8d 00 00 00 <48> 8b 44 24 30 65 48 2b 05 79 06 3f 12 0f 85 c7 02 00 00 48 83 c4 RSP: 0018:ffffc90004a6f4a8 EFLAGS: 00000206 RAX: 0000000000000046 RBX: ffffffff8e5c15a0 RCX: 00000000ef9d33e4 RDX: 0000000000000000 RSI: ffffffff8de2d6e8 RDI: ffffffff8c163300 RBP: 0000000000000002 R08: 0ac0d5affe09d4ff R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000000 R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000 rcu_lock_acquire include/linux/rcupdate.h:331 [inline] rcu_read_lock include/linux/rcupdate.h:841 [inline] class_rcu_constructor include/linux/rcupdate.h:1155 [inline] unwind_next_frame+0xd1/0x20a0 arch/x86/kernel/unwind_orc.c:479 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:156 __set_page_owner+0x91/0x550 mm/page_owner.c:329 set_page_owner include/linux/page_owner.h:32 [inline] post_alloc_hook+0x1c0/0x230 mm/page_alloc.c:1851 prep_new_page mm/page_alloc.c:1859 [inline] get_page_from_freelist+0x132b/0x38e0 mm/page_alloc.c:3858 __alloc_frozen_pages_noprof+0x261/0x23f0 mm/page_alloc.c:5148 alloc_pages_mpol+0x1fb/0x550 mm/mempolicy.c:2416 alloc_frozen_pages_noprof mm/mempolicy.c:2487 [inline] alloc_pages_noprof+0x131/0x390 mm/mempolicy.c:2507 vm_area_alloc_pages mm/vmalloc.c:3642 [inline] __vmalloc_area_node mm/vmalloc.c:3720 [inline] __vmalloc_node_range_noprof+0x72f/0x14b0 mm/vmalloc.c:3893 vmalloc_user_noprof+0x9e/0xe0 mm/vmalloc.c:4046 kcov_ioctl+0x4c/0x730 kernel/kcov.c:716 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:598 [inline] __se_sys_ioctl fs/ioctl.c:584 [inline] __x64_sys_ioctl+0x18b/0x210 fs/ioctl.c:584 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xcd/0x4e0 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7fcbc138e7ab RSP: 002b:00007ffdb3f5f3b0 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 0000000000080000 RCX: 00007fcbc138e7ab RDX: 0000000000080000 RSI: ffffffff80086301 RDI: 00000000000000dc RBP: 00007fcbc15d63f8 R08: 00000000000000da R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000003 R14: 0000000000000009 R15: 0000000000000000 rcu: rcu_preempt kthread starved for 10308 jiffies! g10573 f0x0 RCU_GP_DOING_FQS(6) ->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:27784 pid:16 tgid:16 ppid:2 task_flags:0x208040 flags:0x00004000 Call Trace: context_switch kernel/sched/core.c:5357 [inline] __schedule+0x1190/0x5de0 kernel/sched/core.c:6961 preempt_schedule_irq+0x51/0x90 kernel/sched/core.c:7288 irqentry_exit+0x36/0x90 kernel/entry/common.c:197 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702 RIP: 0010:force_qs_rnp+0x0/0xa90 kernel/rcu/tree.c:2723 Code: fa ff ff 4c 89 4c 24 08 e8 fd d0 80 00 4c 8b 4c 24 08 e9 e3 fd ff ff 0f 1f 00 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 <41> 57 41 56 41 55 41 54 55 53 48 83 ec 68 0f b6 05 70 a0 bb 0c c6 RSP: 0018:ffffc90000157ca0 EFLAGS: 00000246 RAX: 00000000000011d7 RBX: dffffc0000000000 RCX: 0000000000000006 RDX: 0000000000000001 RSI: ffffffff8de52c58 RDI: ffffffff81a0ec10 RBP: 0000000000000000 R08: 0000000000000001 R09: 0000000000000001 R10: ffffffff90ab7297 R11: 0000000000000000 R12: ffffffff8e211200 R13: ffffc90000157d28 R14: 0000000000000000 R15: 0000000000000000 rcu_gp_fqs kernel/rcu/tree.c:2039 [inline] rcu_gp_fqs_loop+0x6e0/0xb00 kernel/rcu/tree.c:2105 rcu_gp_kthread+0x270/0x380 kernel/rcu/tree.c:2285 kthread+0x3c2/0x780 kernel/kthread.c:463 ret_from_fork+0x56a/0x730 arch/x86/kernel/process.c:148 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 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 UID: 0 PID: 0 Comm: swapper/1 Not tainted syzkaller #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/18/2025 RIP: 0010:should_failslab+0x4b/0x120 mm/failslab.c:30 Code: 80 3c 10 00 0f 85 cb 00 00 00 48 39 1d 9e 1f c5 18 0f 84 8e 00 00 00 f7 c6 00 80 00 00 0f 85 82 00 00 00 80 3d 25 35 56 0c 00 <0f> 85 81 00 00 00 80 3d 19 35 56 0c 00 74 27 48 b8 00 00 00 00 00 RSP: 0018:ffffc90000a08038 EFLAGS: 00000246 RAX: 1ffffffff35cf51c RBX: ffff88801facdc80 RCX: ffffffff896a8a29 RDX: dffffc0000000000 RSI: 0000000000000820 RDI: ffff88801facdc80 RBP: ffffc90000a080a8 R08: 0000000000000005 R09: 0000000000000001 R10: 0000000000000002 R11: 0000000000000000 R12: ffff88801facdc80 R13: 0000000000000820 R14: 00000000000000b8 R15: ffff88817e411200 FS: 0000000000000000(0000) GS:ffff8881247b2000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000200000024000 CR3: 000000004bea5000 CR4: 00000000003526f0 Call Trace: slab_pre_alloc_hook mm/slub.c:4144 [inline] slab_alloc_node mm/slub.c:4220 [inline] kmem_cache_alloc_noprof+0x6d/0x3b0 mm/slub.c:4247 skb_ext_maybe_cow net/core/skbuff.c:6994 [inline] skb_ext_add+0xf8/0x7a0 net/core/skbuff.c:7068 nf_bridge_unshare net/bridge/br_netfilter_hooks.c:169 [inline] br_nf_forward_ip.part.0+0x28/0x810 net/bridge/br_netfilter_hooks.c:681 br_nf_forward_ip net/bridge/br_netfilter_hooks.c:676 [inline] br_nf_forward+0xf0f/0x1be0 net/bridge/br_netfilter_hooks.c:773 nf_hook_entry_hookfn include/linux/netfilter.h:158 [inline] nf_hook_slow+0xbb/0x200 net/netfilter/core.c:623 nf_hook+0x45e/0x780 include/linux/netfilter.h:273 NF_HOOK include/linux/netfilter.h:316 [inline] __br_forward+0x1be/0x5b0 net/bridge/br_forward.c:115 deliver_clone net/bridge/br_forward.c:131 [inline] maybe_deliver+0xf1/0x180 net/bridge/br_forward.c:190 br_flood+0x17c/0x650 net/bridge/br_forward.c:237 br_handle_frame_finish+0xf2d/0x1ca0 net/bridge/br_input.c:221 br_nf_hook_thresh+0x307/0x410 net/bridge/br_netfilter_hooks.c:1167 br_nf_pre_routing_finish_ipv6+0x76a/0xfb0 net/bridge/br_netfilter_ipv6.c:154 NF_HOOK include/linux/netfilter.h:318 [inline] br_nf_pre_routing_ipv6+0x3cd/0x8c0 net/bridge/br_netfilter_ipv6.c:184 br_nf_pre_routing+0x860/0x15b0 net/bridge/br_netfilter_hooks.c:508 nf_hook_entry_hookfn include/linux/netfilter.h:158 [inline] nf_hook_bridge_pre net/bridge/br_input.c:283 [inline] br_handle_frame+0xad8/0x14b0 net/bridge/br_input.c:434 __netif_receive_skb_core.constprop.0+0xa25/0x48c0 net/core/dev.c:5878 __netif_receive_skb_one_core+0xb0/0x1e0 net/core/dev.c:5989 __netif_receive_skb+0x1d/0x160 net/core/dev.c:6104 process_backlog+0x442/0x15e0 net/core/dev.c:6456 __napi_poll.constprop.0+0xba/0x550 net/core/dev.c:7506 napi_poll net/core/dev.c:7569 [inline] net_rx_action+0xa9f/0xfe0 net/core/dev.c:7696 handle_softirqs+0x219/0x8e0 kernel/softirq.c:579 __do_softirq kernel/softirq.c:613 [inline] invoke_softirq kernel/softirq.c:453 [inline] __irq_exit_rcu+0x109/0x170 kernel/softirq.c:680 irq_exit_rcu+0x9/0x30 kernel/softirq.c:696 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1050 [inline] sysvec_apic_timer_interrupt+0xa4/0xc0 arch/x86/kernel/apic/apic.c:1050 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702 RIP: 0010:pv_native_safe_halt+0xf/0x20 arch/x86/kernel/paravirt.c:82 Code: 7d 61 02 c3 cc cc cc cc 0f 1f 00 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 f3 0f 1e fa 66 90 0f 00 2d d3 56 15 00 fb f4 cc 09 03 00 66 2e 0f 1f 84 00 00 00 00 00 66 90 90 90 90 90 90 RSP: 0018:ffffc90000197df8 EFLAGS: 000002c2 RAX: 00000000013edf81 RBX: 0000000000000001 RCX: ffffffff8b94bb49 RDX: 0000000000000000 RSI: ffffffff8de52c58 RDI: ffffffff8c163300 RBP: ffffed1003c5d488 R08: 0000000000000001 R09: ffffed10170a6655 R10: ffff8880b85332ab R11: 0000000000000000 R12: 0000000000000001 R13: ffff88801e2ea440 R14: ffffffff90ab7290 R15: 0000000000000000 arch_safe_halt arch/x86/include/asm/paravirt.h:107 [inline] default_idle+0x13/0x20 arch/x86/kernel/process.c:757 default_idle_call+0x6d/0xb0 kernel/sched/idle.c:122 cpuidle_idle_call kernel/sched/idle.c:190 [inline] do_idle+0x391/0x510 kernel/sched/idle.c:330 cpu_startup_entry+0x4f/0x60 kernel/sched/idle.c:428 start_secondary+0x21d/0x2b0 arch/x86/kernel/smpboot.c:315 common_startup_64+0x13e/0x148 net_ratelimit: 26439 callbacks suppressed bridge0: received packet on veth0_to_bridge with own address as source address (addr:82:c9:f3:48:d3:0b, 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:82:c9:f3:48:d3:0b, 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:82:c9:f3:48:d3:0b, 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:82:c9:f3:48:d3:0b, 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:82:c9:f3:48:d3:0b, vlan:0) bridge0: received packet on bridge_slave_0 with own address as source address (addr:aa:aa:aa:aa:aa:1b, vlan:0)