bridge0: received packet on bridge_slave_1 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): P5233/1:b..l rcu: (detected by 0, t=10503 jiffies, g=194409, q=499 ncpus=2) task:syz.3.8293 state:R running task stack:25464 pid:5233 tgid:5233 ppid:30035 task_flags:0x40004c flags:0x00080000 Call Trace: context_switch kernel/sched/core.c:5388 [inline] __schedule+0x1821/0x5740 kernel/sched/core.c:7189 preempt_schedule_irq+0x4d/0xa0 kernel/sched/core.c:7513 irqentry_exit_to_kernel_mode include/linux/irq-entry-common.h:547 [inline] irqentry_exit+0x14f/0x760 kernel/entry/common.c:164 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:697 RIP: 0010:__nr_to_section include/linux/mmzone.h:2065 [inline] RIP: 0010:__pfn_to_section include/linux/mmzone.h:2198 [inline] RIP: 0010:lookup_page_ext mm/page_ext.c:255 [inline] RIP: 0010:page_ext_lookup+0x90/0x180 mm/page_ext.c:513 Code: 74 0c 48 c7 c7 00 ea 4a 9a e8 fc 7d f4 ff 48 8b 05 f5 65 0e 18 48 85 c0 74 36 4e 8d 34 f0 4c 89 f0 48 c1 e8 03 42 80 3c 28 00 <74> 08 4c 89 f7 e8 d6 7d f4 ff 4d 8b 36 4d 85 f6 74 1b 48 c1 eb 0f RSP: 0018:ffffc90014dff488 EFLAGS: 00000246 RAX: 1ffff11047ffc600 RBX: 0000000000076090 RCX: ffff888071dd3d80 RDX: 0000000000000000 RSI: 0000000000001000 RDI: 0000000000000000 RBP: 0000000000000000 R08: ffffffff823ac4fe R09: ffffffff8e95cda0 R10: 000000000000000e R11: ffffffff81b0efc0 R12: 0000000000076090 R13: dffffc0000000000 R14: ffff88823ffe3000 R15: 0000000000001000 page_ext_iter_begin include/linux/page_ext.h:133 [inline] __update_page_owner_free_handle+0x103/0x470 mm/page_owner.c:284 __reset_page_owner+0x85/0x1f0 mm/page_owner.c:321 reset_page_owner include/linux/page_owner.h:25 [inline] __free_pages_prepare mm/page_alloc.c:1402 [inline] free_unref_folios+0xcec/0x1480 mm/page_alloc.c:3004 folios_put_refs+0x9ff/0xb40 mm/swap.c:1008 free_pages_and_swap_cache+0x2b9/0x490 mm/swap_state.c:401 __tlb_batch_free_encoded_pages mm/mmu_gather.c:138 [inline] tlb_batch_pages_flush mm/mmu_gather.c:151 [inline] tlb_flush_mmu_free mm/mmu_gather.c:417 [inline] tlb_flush_mmu+0x6d3/0xa30 mm/mmu_gather.c:424 tlb_finish_mmu+0xf9/0x230 mm/mmu_gather.c:549 exit_mmap+0x498/0x9e0 mm/mmap.c:1313 __mmput+0x118/0x430 kernel/fork.c:1178 exit_mm+0x1f6/0x2d0 kernel/exit.c:582 do_exit+0x6a2/0x22c0 kernel/exit.c:964 do_group_exit+0x21b/0x2d0 kernel/exit.c:1119 __do_sys_exit_group kernel/exit.c:1130 [inline] __se_sys_exit_group kernel/exit.c:1128 [inline] __x64_sys_exit_group+0x3f/0x40 kernel/exit.c:1128 x64_sys_call+0x221a/0x2240 arch/x86/include/generated/asm/syscalls_64.h:232 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0x15f/0xf80 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7fd7c739ce59 RSP: 002b:00007ffec2375ce8 EFLAGS: 00000246 ORIG_RAX: 00000000000000e7 RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007fd7c739ce59 RDX: 0000000000000064 RSI: 0000000000000000 RDI: 0000000000000000 RBP: 00007ffec2375d4c R08: 0000000000000000 R09: 00000000000927c0 R10: 0000000000000006 R11: 0000000000000246 R12: 0000000000000153 R13: 00000000000927c0 R14: 00000000000e6586 R15: 00007ffec2375da0 rcu: rcu_preempt kthread starved for 845 jiffies! g194409 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:27968 pid:16 tgid:16 ppid:2 task_flags:0x208040 flags:0x00080000 Call Trace: context_switch kernel/sched/core.c:5388 [inline] __schedule+0x1821/0x5740 kernel/sched/core.c:7189 __schedule_loop kernel/sched/core.c:7268 [inline] schedule+0x164/0x360 kernel/sched/core.c:7283 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+0x389/0x470 kernel/kthread.c:436 ret_from_fork+0x514/0xb70 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: 9072 Comm: kworker/u8:12 Not tainted syzkaller #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/18/2026 Workqueue: krds_cp_wq#10/4 rds_connect_worker RIP: 0010:__lock_acquire+0x1454/0x2cf0 kernel/locking/lockdep.c:5270 Code: 31 ed 65 48 8b 05 dc 92 97 11 48 3b 84 24 e0 00 00 00 0f 85 69 16 00 00 89 e8 48 81 c4 e8 00 00 00 5b 41 5c 41 5d 41 5e 41 5f <5d> c3 cc cc cc cc cc 4d 85 ff 4c 8b 6c 24 10 0f 84 c8 10 00 00 e8 RSP: 0018:ffffc90000a07880 EFLAGS: 00000082 RAX: 0000000000000001 RBX: 0000000000000000 RCX: 0000000000000000 RDX: 000000007f45ee1d RSI: 000000005970cd9e RDI: ffff8880325b5c40 RBP: 0000000000000001 R08: ffffffff8176f256 R09: ffffffff8e95cda0 R10: ffffc90000a07a88 R11: fffff52000140f5d R12: 0000000000000002 R13: ffffffff8e95cda0 R14: 0000000000000000 R15: 0000000000000246 FS: 0000000000000000(0000) GS:ffff88812538a000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 000055fd14851008 CR3: 0000000036418000 CR4: 00000000003526f0 Call Trace: lock_acquire+0x106/0x350 kernel/locking/lockdep.c:5868 rcu_lock_acquire include/linux/rcupdate.h:300 [inline] rcu_read_lock include/linux/rcupdate.h:838 [inline] class_rcu_constructor include/linux/rcupdate.h:1181 [inline] unwind_next_frame+0xc3/0x2550 arch/x86/kernel/unwind_orc.c:495 __unwind_start+0x5b8/0x760 arch/x86/kernel/unwind_orc.c:787 unwind_start arch/x86/include/asm/unwind.h:64 [inline] arch_stack_walk+0xe3/0x150 arch/x86/kernel/stacktrace.c:24 stack_trace_save+0xa9/0x100 kernel/stacktrace.c:122 kasan_save_stack mm/kasan/common.c:57 [inline] kasan_save_track+0x3e/0x80 mm/kasan/common.c:78 kasan_save_free_info+0x46/0x50 mm/kasan/generic.c:584 poison_slab_object mm/kasan/common.c:253 [inline] __kasan_slab_free+0x5c/0x80 mm/kasan/common.c:285 kasan_slab_free include/linux/kasan.h:235 [inline] slab_free_hook mm/slub.c:2689 [inline] slab_free mm/slub.c:6250 [inline] kmem_cache_free+0x182/0x650 mm/slub.c:6377 skb_ext_reset include/linux/skbuff.h:5116 [inline] skb_release_head_state+0x270/0x360 net/core/skbuff.c:1181 skb_release_all net/core/skbuff.c:1187 [inline] __kfree_skb+0x24/0x210 net/core/skbuff.c:1203 kfree_skb_reason include/linux/skbuff.h:1322 [inline] kfree_skb include/linux/skbuff.h:1331 [inline] ip6_mc_input+0x8de/0xbd0 net/ipv6/ip6_input.c:638 ip_sabotage_in+0x1e1/0x270 net/bridge/br_netfilter_hooks.c:984 nf_hook_entry_hookfn include/linux/netfilter.h:158 [inline] nf_hook_slow+0xc5/0x220 net/netfilter/core.c:619 nf_hook include/linux/netfilter.h:273 [inline] NF_HOOK+0x21f/0x3c0 include/linux/netfilter.h:316 __netif_receive_skb_one_core net/core/dev.c:6202 [inline] __netif_receive_skb net/core/dev.c:6315 [inline] netif_receive_skb_internal net/core/dev.c:6401 [inline] netif_receive_skb+0x278/0xbf0 net/core/dev.c:6460 NF_HOOK+0xa4/0x3a0 include/linux/netfilter.h:318 br_handle_frame_finish+0x1541/0x1c80 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+0x91f/0xc30 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:183 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/0x3170 net/core/dev.c:6089 __netif_receive_skb_one_core net/core/dev.c:6200 [inline] __netif_receive_skb net/core/dev.c:6315 [inline] process_backlog+0x76d/0x1950 net/core/dev.c:6666 __napi_poll+0xae/0x340 net/core/dev.c:7733 napi_poll net/core/dev.c:7796 [inline] net_rx_action+0x627/0xf70 net/core/dev.c:7953 handle_softirqs+0x22a/0x840 kernel/softirq.c:622 __do_softirq kernel/softirq.c:656 [inline] invoke_softirq kernel/softirq.c:496 [inline] __irq_exit_rcu+0xca/0x220 kernel/softirq.c:735 irq_exit_rcu+0x9/0x30 kernel/softirq.c:752 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1061 [inline] sysvec_apic_timer_interrupt+0xa6/0xc0 arch/x86/kernel/apic/apic.c:1061 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:697 RIP: 0010:__schedule+0x1829/0x5740 kernel/sched/core.c:7149 Code: d8 48 c1 e8 03 42 80 3c 30 00 74 08 48 89 df e8 8d 3e 87 f6 4c 89 23 4c 89 ef 4c 89 e6 e8 af 7b 89 f5 48 89 c7 e8 c7 2e eb f5 <31> ff 4d 39 e5 40 0f 95 c7 e8 a9 3a eb f5 48 8b 84 24 00 01 00 00 RSP: 0018:ffffc9000353f4a0 EFLAGS: 00000206 RAX: 00000000010badeb RBX: ffff8880b873ae88 RCX: 0000000080000001 RDX: 0000000000000006 RSI: ffffffff8dfa6c27 RDI: ffffffff8c28af60 RBP: ffffc9000353f6b0 R08: ffffffff9030bcf7 R09: 1ffffffff206179e R10: dffffc0000000000 R11: fffffbfff206179f R12: ffff8880325b5c40 R13: ffff8880325b5c40 R14: dffffc0000000000 R15: ffff8880b873b9f8 preempt_schedule_common+0x82/0xd0 kernel/sched/core.c:7370 preempt_schedule_thunk+0x16/0x30 arch/x86/entry/thunk.S:12 __local_bh_enable_ip+0xe1/0x130 kernel/softirq.c:457 lock_sock include/net/sock.h:1713 [inline] __inet6_bind+0x30c/0xf60 net/ipv6/af_inet6.c:292 kernel_bind+0x13e/0x1c0 net/socket.c:3660 rds_tcp_conn_path_connect+0x53e/0x930 net/rds/tcp_connect.c:175 rds_connect_worker+0x1d8/0x290 net/rds/threads.c:176 process_one_work kernel/workqueue.c:3314 [inline] process_scheduled_works+0xb5d/0x1860 kernel/workqueue.c:3397 worker_thread+0xa53/0xfc0 kernel/workqueue.c:3478 kthread+0x389/0x470 kernel/kthread.c:436 ret_from_fork+0x514/0xb70 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 net_ratelimit: 7257 callbacks suppressed bridge0: received packet on bridge_slave_1 with own address as source address (addr:aa:aa:aa:aa:aa:1c, vlan:0) bridge0: received packet on veth1_to_bridge with own address as source address (addr:72:25:f0:6f:fa:ee, vlan:0) bridge0: received packet on bridge_slave_1 with own address as source address (addr:aa:aa:aa:aa:aa:1c, vlan:0) bridge0: received packet on bridge_slave_1 with own address as source address (addr:aa:aa:aa:aa:aa:0c, vlan:0) bridge0: received packet on bridge_slave_1 with own address as source address (addr:aa:aa:aa:aa:aa:1c, vlan:0) bridge0: received packet on veth1_to_bridge with own address as source address (addr:aa:aa:aa:aa:aa:0c, vlan:0) bridge0: received packet on veth1_to_bridge with own address as source address (addr:72:25:f0:6f:fa:ee, vlan:0) bridge0: received packet on bridge_slave_1 with own address as source address (addr:aa:aa:aa:aa:aa:0c, vlan:0) bridge0: received packet on veth1_to_bridge with own address as source address (addr:aa:aa:aa:aa:aa:0c, vlan:0) bridge0: received packet on veth1_to_bridge with own address as source address (addr:72:25:f0:6f:fa:ee, vlan:0) net_ratelimit: 17095 callbacks suppressed bridge0: received packet on veth1_to_bridge with own address as source address (addr:aa:aa:aa:aa:aa:0c, vlan:0) bridge0: received packet on bridge_slave_1 with own address as source address (addr:aa:aa:aa:aa:aa:1c, vlan:0) bridge0: received packet on veth1_to_bridge with own address as source address (addr:72:25:f0:6f:fa:ee, vlan:0) bridge0: received packet on bridge_slave_1 with own address as source address (addr:aa:aa:aa:aa:aa:0c, vlan:0) bridge0: received packet on bridge_slave_1 with own address as source address (addr:aa:aa:aa:aa:aa:1c, vlan:0) bridge0: received packet on veth1_to_bridge with own address as source address (addr:aa:aa:aa:aa:aa:0c, vlan:0) bridge0: received packet on veth1_to_bridge with own address as source address (addr:72:25:f0:6f:fa:ee, vlan:0) bridge0: received packet on bridge_slave_1 with own address as source address (addr:aa:aa:aa:aa:aa:0c, vlan:0) bridge0: received packet on bridge_slave_1 with own address as source address (addr:aa:aa:aa:aa:aa:1c, vlan:0) bridge0: received packet on veth1_to_bridge with own address as source address (addr:aa:aa:aa:aa:aa:0c, vlan:0)