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): P20538/1:b..l rcu: (detected by 0, t=10502 jiffies, g=81465, q=1962 ncpus=2) task:syz.0.3887 state:R running task stack:25960 pid:20538 tgid:20533 ppid:16217 task_flags:0x400140 flags:0x00080002 Call Trace: context_switch kernel/sched/core.c:5295 [inline] __schedule+0x1585/0x5340 kernel/sched/core.c:6907 preempt_schedule_irq+0x4d/0xa0 kernel/sched/core.c:7234 irqentry_exit+0x599/0x620 kernel/entry/common.c:239 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:697 RIP: 0010:check_kcov_mode kernel/kcov.c:185 [inline] RIP: 0010:write_comp_data kernel/kcov.c:246 [inline] RIP: 0010:__sanitizer_cov_trace_const_cmp8+0x30/0x90 kernel/kcov.c:321 Code: 04 24 65 48 8b 0d 88 0e 56 11 65 8b 15 a9 0e 56 11 81 e2 00 01 ff 00 74 11 81 fa 00 01 00 00 75 57 83 b9 54 16 00 00 00 74 4e <8b> 91 30 16 00 00 83 fa 03 75 43 48 8b 91 38 16 00 00 44 8b 89 34 RSP: 0018:ffffc90010a5f0d0 EFLAGS: 00000246 RAX: ffffffff823bea9c RBX: 0000000000067fea RCX: ffff888026f2dac0 RDX: 0000000000000000 RSI: 0000000000007fea RDI: 0000000000000000 RBP: dffffc0000000000 R08: ffff88801da7f91f R09: 1ffff11003b4ff23 R10: dffffc0000000000 R11: ffffed1003b4ff24 R12: 0000000000000000 R13: 0000000000067fea R14: dffffc0000000000 R15: ffff88801da7f8d0 page_ext_iter_next_fast_possible include/linux/page_ext.h:80 [inline] page_ext_iter_next include/linux/page_ext.h:156 [inline] __page_table_check_zero+0x23c/0x3e0 mm/page_table_check.c:139 page_table_check_alloc include/linux/page_table_check.h:38 [inline] post_alloc_hook+0x240/0x280 mm/page_alloc.c:1890 prep_new_page mm/page_alloc.c:1897 [inline] get_page_from_freelist+0x24dc/0x2580 mm/page_alloc.c:3962 __alloc_frozen_pages_noprof+0x18d/0x380 mm/page_alloc.c:5250 alloc_pages_mpol+0x232/0x4a0 mm/mempolicy.c:2485 folio_alloc_mpol_noprof+0x39/0x70 mm/mempolicy.c:2504 shmem_alloc_folio mm/shmem.c:1930 [inline] shmem_alloc_and_add_folio+0x445/0xf80 mm/shmem.c:1972 shmem_get_folio_gfp+0x5a9/0x1670 mm/shmem.c:2567 shmem_fault+0x179/0x390 mm/shmem.c:2768 __do_fault+0x138/0x390 mm/memory.c:5363 do_read_fault mm/memory.c:5798 [inline] do_fault mm/memory.c:5932 [inline] do_pte_missing+0x228f/0x3750 mm/memory.c:4477 handle_pte_fault mm/memory.c:6316 [inline] __handle_mm_fault mm/memory.c:6454 [inline] handle_mm_fault+0x1bec/0x3310 mm/memory.c:6623 faultin_page mm/gup.c:1126 [inline] __get_user_pages+0x165b/0x29d0 mm/gup.c:1428 populate_vma_page_range+0x2be/0x3c0 mm/gup.c:1860 __mm_populate+0x25f/0x390 mm/gup.c:1963 mm_populate include/linux/mm.h:3899 [inline] vm_mmap_pgoff+0x3aa/0x4f0 mm/util.c:586 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0x14d/0xf80 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7ff070f9c629 RSP: 002b:00007ff071f16028 EFLAGS: 00000246 ORIG_RAX: 0000000000000009 RAX: ffffffffffffffda RBX: 00007ff071216090 RCX: 00007ff070f9c629 RDX: b635773f07ebbeef RSI: 0000000000b36000 RDI: 0000200000000000 RBP: 00007ff071032b39 R08: ffffffffffffffff R09: 00000000215e8000 R10: 0000000000008031 R11: 0000000000000246 R12: 0000000000000000 R13: 00007ff071216128 R14: 00007ff071216090 R15: 00007ffc19152778 rcu: rcu_preempt kthread starved for 1187 jiffies! g81465 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:27664 pid:16 tgid:16 ppid:2 task_flags:0x208040 flags:0x00080000 Call Trace: context_switch kernel/sched/core.c:5295 [inline] __schedule+0x1585/0x5340 kernel/sched/core.c:6907 __schedule_loop kernel/sched/core.c:6989 [inline] schedule+0x164/0x360 kernel/sched/core.c:7004 schedule_timeout+0x158/0x2c0 kernel/time/sleep_timeout.c:99 rcu_gp_fqs_loop+0x312/0x11d0 kernel/rcu/tree.c:2095 rcu_gp_kthread+0x9e/0x2b0 kernel/rcu/tree.c:2297 kthread+0x388/0x470 kernel/kthread.c:467 ret_from_fork+0x51e/0xb90 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 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 UID: 0 PID: 12 Comm: kworker/u8:0 Not tainted syzkaller #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2026 Workqueue: events_unbound toggle_allocation_gate RIP: 0010:nf_hook include/linux/netfilter.h:274 [inline] RIP: 0010:NF_HOOK+0x22a/0x3c0 include/linux/netfilter.h:316 Code: 48 8b 44 24 28 48 89 84 24 88 00 00 00 48 8b 7c 24 20 4c 89 ee 4c 89 f2 31 c9 e8 01 3b 76 ff 89 c3 43 c7 44 3c 04 f8 f8 f8 f8 <66> 43 c7 44 3c 08 f8 f8 eb 0a e8 77 2a 76 f7 bb 01 00 00 00 e8 dd RSP: 0018:ffffc90000a080a0 EFLAGS: 00000282 RAX: 0000000000000000 RBX: 0000000000000000 RCX: ffff88801d2e8000 RDX: 0000000000000100 RSI: ffffffff8fc43120 RDI: 0000000000000002 RBP: ffffc90000a081b0 R08: ffff88801d2e8000 R09: 0000000000000004 R10: 0000000000000003 R11: 0000000000000100 R12: 1ffff9200014101c R13: ffffc90000a08100 R14: ffff8880337c9b00 R15: dffffc0000000000 FS: 0000000000000000(0000) GS:ffff888125566000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000555592c7a4e8 CR3: 000000000e54c000 CR4: 00000000003526f0 Call Trace: __netif_receive_skb_one_core net/core/dev.c:6154 [inline] __netif_receive_skb net/core/dev.c:6267 [inline] netif_receive_skb_internal net/core/dev.c:6353 [inline] netif_receive_skb+0x278/0xc50 net/core/dev.c:6412 NF_HOOK+0xa4/0x3a0 include/linux/netfilter.h:319 br_handle_frame_finish+0x14b2/0x1b40 net/bridge/br_input.c:-1 br_nf_hook_thresh+0x3dd/0x4c0 net/bridge/br_netfilter_hooks.c:-1 br_nf_pre_routing_finish_ipv6+0xa3a/0xd70 net/bridge/br_netfilter_ipv6.c:-1 NF_HOOK include/linux/netfilter.h:318 [inline] br_nf_pre_routing_ipv6+0x374/0x6f0 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+0x1277/0x1510 net/bridge/br_input.c:442 __netif_receive_skb_core+0x98f/0x31a0 net/core/dev.c:6041 __netif_receive_skb_one_core net/core/dev.c:6152 [inline] __netif_receive_skb net/core/dev.c:6267 [inline] process_backlog+0x76d/0x1950 net/core/dev.c:6619 __napi_poll+0xae/0x340 net/core/dev.c:7683 napi_poll net/core/dev.c:7746 [inline] net_rx_action+0x627/0xf70 net/core/dev.c:7898 handle_softirqs+0x22a/0x870 kernel/softirq.c:622 __do_softirq kernel/softirq.c:656 [inline] invoke_softirq kernel/softirq.c:496 [inline] __irq_exit_rcu+0x5f/0x150 kernel/softirq.c:723 irq_exit_rcu+0x9/0x30 kernel/softirq.c:739 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1056 [inline] sysvec_apic_timer_interrupt+0xa6/0xc0 arch/x86/kernel/apic/apic.c:1056 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+0xce5/0x12c0 kernel/smp.c:877 Code: 45 8b 2c 24 44 89 ee 83 e6 01 31 ff e8 24 e3 0b 00 41 83 e5 01 49 bd 00 00 00 00 00 fc ff df 75 07 e8 cf de 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 b3 de RSP: 0018:ffffc90000117720 EFLAGS: 00000293 RAX: ffffffff81b9addd RBX: 1ffff110170c8515 RCX: ffff88801d2e8000 RDX: 0000000000000000 RSI: 0000000000000001 RDI: 0000000000000000 RBP: ffffc90000117860 R08: ffffffff901172b7 R09: 1ffffffff2022e56 R10: dffffc0000000000 R11: fffffbfff2022e57 R12: ffff8880b86428a8 R13: dffffc0000000000 R14: ffff8880b873bf80 R15: 0000000000000000 on_each_cpu_cond_mask+0x3f/0x80 kernel/smp.c:1043 on_each_cpu include/linux/smp.h:72 [inline] smp_text_poke_sync_each_cpu arch/x86/kernel/alternative.c:2746 [inline] smp_text_poke_batch_finish+0x5f5/0x1160 arch/x86/kernel/alternative.c:2956 arch_jump_label_transform_apply+0x1c/0x30 arch/x86/kernel/jump_label.c:146 static_key_enable_cpuslocked+0x128/0x240 kernel/jump_label.c:210 static_key_enable+0x1a/0x20 kernel/jump_label.c:223 toggle_allocation_gate+0xab/0x290 mm/kfence/core.c:899 process_one_work kernel/workqueue.c:3275 [inline] process_scheduled_works+0xb02/0x1830 kernel/workqueue.c:3358 worker_thread+0xa50/0xfc0 kernel/workqueue.c:3439 kthread+0x388/0x470 kernel/kthread.c:467 ret_from_fork+0x51e/0xb90 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 net_ratelimit: 31535 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 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:fa:5f:10:2b:2c:78, 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) bridge0: received packet on bridge_slave_0 with own address as source address (addr:aa:aa:aa:aa:aa:0c, vlan:0) lec0: NETDEV WATCHDOG: CPU: 1: transmit queue 0 timed out 5010 ms lec:lec_tx_timeout: lec0 lec:lec_start_xmit: lec0:No lecd attached net_ratelimit: 40635 callbacks suppressed bridge0: received packet on veth0_to_bridge with own address as source address (addr:fa:5f:10:2b:2c:78, 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 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 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: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: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) lec0: NETDEV WATCHDOG: CPU: 1: transmit queue 0 timed out 5010 ms lec:lec_tx_timeout: lec0 lec:lec_start_xmit: lec0:No lecd attached