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): P9475/1:b..l rcu: (detected by 0, t=10503 jiffies, g=274821, q=1704 ncpus=2) task:syz.6.9495 state:R running task stack:25800 pid:9475 tgid:9470 ppid:1427 task_flags:0x40054c flags:0x00080003 Call Trace: context_switch kernel/sched/core.c:5388 [inline] __schedule+0x17b4/0x5680 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/0x730 kernel/entry/common.c:164 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:697 RIP: 0010:deref_stack_reg arch/x86/kernel/unwind_orc.c:422 [inline] RIP: 0010:unwind_next_frame+0xeff/0x2550 arch/x86/kernel/unwind_orc.c:614 Code: 00 00 48 89 c3 48 bd 00 00 00 00 00 fc ff df 48 8b 44 24 30 80 3c 28 00 4c 8b 7c 24 10 74 08 4c 89 ff e8 24 fb b9 00 49 89 1f <48> 8b 44 24 58 80 3c 28 00 48 8b 5c 24 78 4c 8b 64 24 18 74 08 48 RSP: 0018:ffffc900065e6d78 EFLAGS: 00000246 RAX: 1ffff92000cbcdd2 RBX: ffffffff81872cef RCX: 1ffff92000cbcd01 RDX: ffffffff90c67e62 RSI: 0000000000000002 RDI: ffffc900065e7af8 RBP: dffffc0000000000 R08: 0000000000000007 R09: ffffffff8e95cd60 R10: ffffc900065e6e98 R11: ffffffff81b0e910 R12: ffffc900065e8000 R13: 1ffff92000cbcdcb R14: ffffc900065e6e48 R15: ffffc900065e6e90 arch_stack_walk+0x11b/0x150 arch/x86/kernel/stacktrace.c:25 stack_trace_save+0xa9/0x100 kernel/stacktrace.c:122 save_stack+0x122/0x230 mm/page_owner.c:165 __reset_page_owner+0x71/0x1f0 mm/page_owner.c:320 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 folio_batch_release include/linux/folio_batch.h:101 [inline] shmem_undo_range+0x52c/0x1660 mm/shmem.c:1149 shmem_truncate_range mm/shmem.c:1277 [inline] shmem_evict_inode+0x289/0xae0 mm/shmem.c:1407 evict+0x61e/0xb10 fs/inode.c:841 __dentry_kill+0x1a2/0x690 fs/dcache.c:718 finish_dput+0xc9/0x480 fs/dcache.c:927 __fput+0x691/0xa60 fs/file_table.c:518 task_work_run+0x1d9/0x270 kernel/task_work.c:233 exit_task_work include/linux/task_work.h:40 [inline] do_exit+0x70f/0x22c0 kernel/exit.c:975 do_group_exit+0x21b/0x2d0 kernel/exit.c:1117 get_signal+0x1284/0x1330 kernel/signal.c:3037 arch_do_signal_or_restart+0xbc/0x830 arch/x86/kernel/signal.c:337 __exit_to_user_mode_loop kernel/entry/common.c:64 [inline] exit_to_user_mode_loop+0x86/0x480 kernel/entry/common.c:98 __exit_to_user_mode_prepare include/linux/irq-entry-common.h:207 [inline] syscall_exit_to_user_mode_prepare include/linux/irq-entry-common.h:238 [inline] syscall_exit_to_user_mode include/linux/entry-common.h:318 [inline] do_syscall_64+0x33e/0xf80 arch/x86/entry/syscall_64.c:100 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f063f79cdd9 RSP: 002b:00007f0640643028 EFLAGS: 00000246 ORIG_RAX: 0000000000000009 RAX: 0000200000000000 RBX: 00007f063fa16090 RCX: 00007f063f79cdd9 RDX: b635773f07ebbee6 RSI: 0000000000b36000 RDI: 0000200000000000 RBP: 00007f063f832d69 R08: 0000000000000004 R09: 00000000215eb000 R10: 0000000000008031 R11: 0000000000000246 R12: 0000000000000000 R13: 00007f063fa16128 R14: 00007f063fa16090 R15: 00007fff776b9078 rcu: rcu_preempt kthread starved for 2013 jiffies! g274821 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:27544 pid:16 tgid:16 ppid:2 task_flags:0x208040 flags:0x00080000 Call Trace: context_switch kernel/sched/core.c:5388 [inline] __schedule+0x17b4/0x5680 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+0x388/0x470 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: 16461 Comm: kworker/u8:16 Not tainted syzkaller #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/18/2026 Workqueue: krds_cp_wq#1/0 rds_connect_worker RIP: 0010:__rcu_read_unlock+0xc/0xe0 kernel/rcu/tree_plugin.h:431 Code: 89 df e8 07 6e 85 00 eb d2 0f 1f 44 00 00 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 f3 0f 1e fa 41 57 41 56 41 55 41 54 <53> 49 bf 00 00 00 00 00 fc ff df 65 48 8b 3d 29 a3 8d 11 48 8d 9f RSP: 0018:ffffc90000a07bb0 EFLAGS: 00000286 RAX: 822463d7d4012200 RBX: ffffc90000a07c01 RCX: 0000000080000101 RDX: 0000000000000006 RSI: ffffffff8e219c6f RDI: ffffffff8c28ade0 RBP: dffffc0000000000 R08: ffffc90000a07d07 R09: 0000000000000000 R10: ffffc90000a07cf8 R11: fffff52000140fa1 R12: ffffc90005ba7628 R13: ffffc90005ba0000 R14: ffffc90000a07ca8 R15: ffffffff8176f256 FS: 0000000000000000(0000) GS:ffff88812538d000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 000055558f7d94e8 CR3: 000000007eec0000 CR4: 00000000003526f0 Call Trace: rcu_read_unlock include/linux/rcupdate.h:871 [inline] class_rcu_destructor include/linux/rcupdate.h:1181 [inline] unwind_next_frame+0x1bbf/0x2550 arch/x86/kernel/unwind_orc.c:709 arch_stack_walk+0x11b/0x150 arch/x86/kernel/stacktrace.c:25 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 unpoison_slab_object mm/kasan/common.c:340 [inline] __kasan_slab_alloc+0x6c/0x80 mm/kasan/common.c:366 kasan_slab_alloc include/linux/kasan.h:253 [inline] slab_post_alloc_hook mm/slub.c:4569 [inline] slab_alloc_node mm/slub.c:4898 [inline] kmem_cache_alloc_noprof+0x2bc/0x650 mm/slub.c:4905 skb_ext_maybe_cow net/core/skbuff.c:7063 [inline] skb_ext_add+0x1b6/0x8f0 net/core/skbuff.c:7138 nf_bridge_unshare net/bridge/br_netfilter_hooks.c:170 [inline] br_nf_forward_ip+0xc3/0xa30 net/bridge/br_netfilter_hooks.c:682 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+0x23e/0x3f0 include/linux/netfilter.h:316 __br_forward+0x397/0x540 net/bridge/br_forward.c:115 br_handle_frame_finish+0x1521/0x1c80 net/bridge/br_input.c:229 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:__raw_spin_unlock_irqrestore include/linux/spinlock_api_smp.h:179 [inline] RIP: 0010:_raw_spin_unlock_irqrestore+0x47/0x80 kernel/locking/spinlock.c:198 Code: f7 e8 ad f5 f6 f5 f7 c3 00 02 00 00 74 05 e8 b0 8b 22 f6 9c 58 a9 00 02 00 00 75 27 f7 c3 00 02 00 00 74 01 fb bf 01 00 00 00 24 78 e8 f5 65 8b 05 ed d0 8d 07 85 c0 74 18 5b 41 5e e9 51 48 RSP: 0018:ffffc90005ba7410 EFLAGS: 00000206 RAX: 0000000000000006 RBX: 0000000000000286 RCX: 0000000080000001 RDX: 0000000000000007 RSI: ffffffff8dfa6882 RDI: 0000000000000001 RBP: 0000000000000000 R08: ffffffff9030b0f7 R09: 1ffffffff206161e R10: dffffc0000000000 R11: fffffbfff206161f R12: ffff888048180000 R13: ffff88804817c000 R14: ffffffff9a6d74e8 R15: 0000000000000003 __debug_check_no_obj_freed lib/debugobjects.c:1125 [inline] debug_check_no_obj_freed+0x52e/0x550 lib/debugobjects.c:1146 __free_pages_prepare mm/page_alloc.c:1409 [inline] __free_frozen_pages+0x593/0xd30 mm/page_alloc.c:2943 __slab_free+0x274/0x2c0 mm/slub.c:5612 qlink_free mm/kasan/quarantine.c:163 [inline] qlist_free_all+0x99/0x100 mm/kasan/quarantine.c:179 kasan_quarantine_reduce+0x148/0x160 mm/kasan/quarantine.c:286 __kasan_kmalloc+0x22/0xb0 mm/kasan/common.c:406 kasan_kmalloc include/linux/kasan.h:263 [inline] __kmalloc_cache_noprof+0x31c/0x660 mm/slub.c:5419 kmalloc_noprof include/linux/slab.h:950 [inline] kzalloc_noprof include/linux/slab.h:1188 [inline] ref_tracker_alloc+0x15a/0x4c0 lib/ref_tracker.c:270 __netns_tracker_alloc include/net/net_namespace.h:367 [inline] sk_alloc+0x2c3/0x390 net/core/sock.c:2324 inet_create+0x7a0/0x1000 net/ipv4/af_inet.c:333 __sock_create+0x4b2/0x9d0 net/socket.c:1664 rds_tcp_conn_path_connect+0x2d7/0x930 net/rds/tcp_connect.c:-1 rds_connect_worker+0x1d8/0x290 net/rds/threads.c:176 process_one_work kernel/workqueue.c:3302 [inline] process_scheduled_works+0xb5d/0x1860 kernel/workqueue.c:3385 worker_thread+0xa53/0xfc0 kernel/workqueue.c:3466 kthread+0x388/0x470 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: 14748 callbacks suppressed bridge0: received packet on veth1_to_bridge with own address as source address (addr:fa:b1:c5:cb:cc:8c, 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:fa:b1:c5:cb:cc:8c, 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:fa:b1:c5:cb:cc:8c, 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:fa:b1:c5:cb:cc:8c, 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:fa:b1:c5:cb:cc:8c, vlan:0) bridge0: received packet on bridge_slave_1 with own address as source address (addr:aa:aa:aa:aa:aa:1c, vlan:0) net_ratelimit: 21026 callbacks suppressed 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:fa:b1:c5:cb:cc:8c, 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:fa:b1:c5:cb:cc:8c, 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:fa:b1:c5:cb:cc:8c, 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:fa:b1:c5:cb:cc:8c, 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:fa:b1:c5:cb:cc:8c, vlan:0)