bridge0: received packet on veth0_to_bridge with own address as source address (addr:26:9d:25:72:02:08, vlan:0) rcu: INFO: rcu_preempt detected stalls on CPUs/tasks: rcu: (detected by 0, t=10502 jiffies, g=25197, q=939 ncpus=2) rcu: All QSes seen, last rcu_preempt kthread activity 7357 (4294970166-4294962809), jiffies_till_next_fqs=1, root ->qsmask 0x0 rcu: rcu_preempt kthread starved for 7357 jiffies! g25197 f0x2 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:28128 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 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:__debug_object_init+0x12/0x4e0 lib/debugobjects.c:732 Code: 0f 1f 84 00 00 00 00 00 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 55 41 57 41 56 41 55 41 54 53 48 83 ec 20 89 54 24 10 <48> 89 fb 66 90 8b 05 7b 48 38 0a 3b 05 79 48 38 0a 0f 82 7a 03 00 RSP: 0018:ffffc90000157a28 EFLAGS: 00000286 RAX: ffffffff81b16f9d RBX: dffffc0000000000 RCX: ffff88801d680000 RDX: 0000000000000001 RSI: ffffffff8bcf3c40 RDI: ffffc90000157b00 RBP: 0000000000000000 R08: ffffffff9a2b64e0 R09: 0000000000000000 R10: ffffc90000157b00 R11: fffff5200002af6a R12: ffffffff81b2a970 R13: ffffc90000157b00 R14: ffffffff8bcf5b20 R15: ffffc90000157b00 timer_init_key_on_stack+0x3c/0x110 kernel/time/timer.c:816 schedule_timeout+0x146/0x2c0 kernel/time/sleep_timeout.c:96 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: 6165 Comm: kworker/u8:14 Tainted: G L syzkaller #0 PREEMPT(full) Tainted: [L]=SOFTLOCKUP Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2026 Workqueue: writeback wb_workfn (flush-8:0) RIP: 0010:trace_hardirqs_off+0x5/0x40 kernel/trace/trace_preemptirq.c:104 Code: fe ff ff 90 0f 0b 90 e9 2c ff ff ff 66 0f 1f 84 00 00 00 00 00 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 f3 0f 1e fa 53 <48> 8b 5c 24 08 48 89 df e8 be b1 df 09 65 8b 05 c7 61 4f 11 85 c0 RSP: 0018:ffffc90000a084e8 EFLAGS: 00000006 RAX: e8d5c2d4dcafd200 RBX: 0000000000000202 RCX: ffffffff89776c00 RDX: ffffc90000a08600 RSI: ffff88801ce92d80 RDI: ffff88801ce92d80 RBP: ffffc90000a085a8 R08: 00000000000000b8 R09: ffff8880b87431a0 R10: ffff888047c4ea28 R11: ffffed1008f89d48 R12: 0000000000000820 R13: 0000000000000001 R14: ffff88801ce92d80 R15: ffffffff89776cc8 FS: 0000000000000000(0000) GS:ffff888125564000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00002000002e9030 CR3: 00000000684da000 CR4: 00000000003526f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 00000000f1ffffdf DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000400 Call Trace: __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:130 [inline] _raw_spin_lock_irqsave+0x1a/0x60 kernel/locking/spinlock.c:162 get_from_partial_node+0x54/0x500 mm/slub.c:3773 get_from_partial mm/slub.c:3901 [inline] ___slab_alloc+0xae/0x6b0 mm/slub.c:4372 __slab_alloc_node mm/slub.c:4442 [inline] slab_alloc_node mm/slub.c:4818 [inline] kmem_cache_alloc_noprof+0x12d/0x650 mm/slub.c:4837 __skb_ext_alloc net/core/skbuff.c:7061 [inline] skb_ext_add+0x148/0x8f0 net/core/skbuff.c:7165 nf_bridge_alloc include/net/netfilter/br_netfilter.h:12 [inline] br_nf_pre_routing_ipv6+0x12e/0x6f0 net/bridge/br_netfilter_ipv6.c:172 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:6043 __netif_receive_skb_one_core net/core/dev.c:6154 [inline] __netif_receive_skb net/core/dev.c:6269 [inline] process_backlog+0x76d/0x1950 net/core/dev.c:6620 __napi_poll+0xae/0x340 net/core/dev.c:7684 napi_poll net/core/dev.c:7747 [inline] net_rx_action+0x627/0xf70 net/core/dev.c:7899 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:arch_try_cmpxchg128 arch/x86/include/asm/cmpxchg_64.h:83 [inline] RIP: 0010:__update_freelist_fast mm/slub.c:637 [inline] RIP: 0010:slab_update_freelist mm/slub.c:703 [inline] RIP: 0010:__slab_free+0x105/0x2b0 mm/slub.c:5483 Code: fa 41 f7 c5 00 02 00 00 75 42 4c 89 f7 48 8d 74 24 40 48 8d 54 24 30 e8 79 7a 00 00 89 c3 eb 4a 48 8b 5c 24 30 48 8b 4c 24 38 <48> 8b 44 24 40 48 8b 54 24 48 f0 49 0f c7 4e 20 0f 84 86 00 00 00 RSP: 0018:ffffc9000bdbe1c0 EFLAGS: 00000202 RAX: 000000000000000b RBX: ffff888032c6fa00 RCX: 000000000010000b RDX: ffff888032c6fa00 RSI: ffff888032c6fa00 RDI: 0000000000000000 RBP: ffffc9000bdbe250 R08: 0000000000000001 R09: ffffffff822fc2fc R10: dffffc0000000000 R11: fffffbfff2023037 R12: 0000000000000000 R13: ffff88801daa6c80 R14: ffffea0000cb1bc0 R15: ffff888032c6f900 qlink_free mm/kasan/quarantine.c:163 [inline] qlist_free_all+0x97/0x100 mm/kasan/quarantine.c:179 kasan_quarantine_reduce+0x148/0x160 mm/kasan/quarantine.c:286 __kasan_slab_alloc+0x22/0x80 mm/kasan/common.c:350 kasan_slab_alloc include/linux/kasan.h:253 [inline] slab_post_alloc_hook mm/slub.c:4501 [inline] slab_alloc_node mm/slub.c:4830 [inline] kmem_cache_alloc_noprof+0x2bc/0x650 mm/slub.c:4837 ext4_mb_pa_alloc fs/ext4/mballoc.c:5726 [inline] ext4_mb_new_blocks+0xc99/0x4780 fs/ext4/mballoc.c:6311 ext4_new_meta_blocks+0x18c/0x410 fs/ext4/balloc.c:750 ext4_ext_grow_indepth fs/ext4/extents.c:1330 [inline] ext4_ext_create_new_leaf fs/ext4/extents.c:1434 [inline] ext4_ext_insert_extent+0xec9/0x4b50 fs/ext4/extents.c:2120 ext4_ext_map_blocks+0x1696/0x58b0 fs/ext4/extents.c:4457 ext4_map_create_blocks+0x11d/0x540 fs/ext4/inode.c:616 ext4_map_blocks+0x7cd/0x11d0 fs/ext4/inode.c:809 mpage_map_one_extent fs/ext4/inode.c:2373 [inline] mpage_map_and_submit_extent fs/ext4/inode.c:2467 [inline] ext4_do_writepages+0x22c0/0x46e0 fs/ext4/inode.c:2925 ext4_writepages+0x241/0x3b0 fs/ext4/inode.c:3019 do_writepages+0x32e/0x550 mm/page-writeback.c:2554 __writeback_single_inode+0x133/0x11a0 fs/fs-writeback.c:1750 writeback_sb_inodes+0x992/0x1a20 fs/fs-writeback.c:2042 __writeback_inodes_wb+0x111/0x240 fs/fs-writeback.c:2118 wb_writeback+0x46a/0xb70 fs/fs-writeback.c:2229 wb_check_old_data_flush fs/fs-writeback.c:2333 [inline] wb_do_writeback fs/fs-writeback.c:2386 [inline] wb_workfn+0xb4c/0xf50 fs/fs-writeback.c:2414 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: 20030 callbacks suppressed 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:26:9d:25:72:02:08, 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:26:9d:25:72:02:08, 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 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: 22060 callbacks suppressed 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:26:9d:25:72:02:08, 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:26:9d:25:72:02:08, 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 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)