rcu: INFO: rcu_preempt detected stalls on CPUs/tasks: rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P1131/1:b..l rcu: (detected by 1, t=10502 jiffies, g=68817, q=1179 ncpus=2) task:kworker/u8:8 state:R running task stack:22144 pid:1131 tgid:1131 ppid:2 task_flags:0x4208160 flags:0x00080000 Workqueue: krds_cp_wq#4/0 rds_connect_worker Call Trace: context_switch kernel/sched/core.c:5510 [inline] __schedule+0x17d9/0x56c0 kernel/sched/core.c:7234 preempt_schedule_irq+0x4d/0xa0 kernel/sched/core.c:7556 irqentry_exit_to_kernel_mode include/linux/irq-entry-common.h:539 [inline] irqentry_exit+0x14f/0x8f0 kernel/entry/common.c:167 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:674 RIP: 0010:orc_ip arch/x86/kernel/unwind_orc.c:81 [inline] RIP: 0010:__orc_find arch/x86/kernel/unwind_orc.c:103 [inline] RIP: 0010:orc_find arch/x86/kernel/unwind_orc.c:238 [inline] RIP: 0010:unwind_next_frame+0x4e2/0x2550 arch/x86/kernel/unwind_orc.c:510 Code: e9 ee 01 00 00 49 89 d5 49 89 d7 4c 89 e0 4c 29 f8 48 89 c1 48 c1 f9 02 48 c1 e8 3f 48 01 c8 48 83 e0 fe 49 8d 1c 47 48 89 d8 <48> c1 e8 03 48 b9 00 00 00 00 00 fc ff df 0f b6 04 08 84 c0 75 27 RSP: 0018:ffffc9000540f220 EFLAGS: 00000246 RAX: ffffffff90a59ff0 RBX: ffffffff90a59ff0 RCX: 0000000000000000 RDX: ffffffff90a59ff0 RSI: ffffffff914ec052 RDI: ffffffff8c2a9f20 RBP: ffffffff897cf109 R08: 0000000000000001 R09: 0000000000000000 R10: 0000000000000000 R11: ffffffff8e959c20 R12: ffffffff90a59ff0 R13: ffffffff90a59ff0 R14: ffffc9000540f2c8 R15: ffffffff90a59ff0 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:1406 [inline] __free_frozen_pages+0xc1e/0xd10 mm/page_alloc.c:2950 __slab_free+0x274/0x2c0 mm/slub.c:5767 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] __do_kmalloc_node mm/slub.c:5362 [inline] __kmalloc_noprof+0x375/0x720 mm/slub.c:5387 _kmalloc_noprof include/linux/slab.h:973 [inline] _kzalloc_noprof include/linux/slab.h:1290 [inline] lsm_blob_alloc security/security.c:218 [inline] lsm_sock_alloc security/security.c:4478 [inline] security_sk_alloc+0x52/0x360 security/security.c:4494 sk_prot_alloc+0x101/0x210 net/core/sock.c:2255 sk_alloc+0x3a/0x390 net/core/sock.c:2308 inet_create+0x7a9/0xff0 net/ipv4/af_inet.c:333 __sock_create+0x4b3/0x9d0 net/socket.c:1651 rds_tcp_conn_path_connect+0x2d8/0x920 net/rds/tcp_connect.c:-1 rds_connect_worker+0x1d8/0x290 net/rds/threads.c:176 process_one_work kernel/workqueue.c:3322 [inline] process_scheduled_works+0xa8e/0x14e0 kernel/workqueue.c:3405 worker_thread+0xa47/0xfb0 kernel/workqueue.c:3486 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: rcu_preempt kthread starved for 9741 jiffies! g68817 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:27496 pid:16 tgid:16 ppid:2 task_flags:0x208040 flags:0x00080000 Call Trace: context_switch kernel/sched/core.c:5510 [inline] __schedule+0x17d9/0x56c0 kernel/sched/core.c:7234 __schedule_loop kernel/sched/core.c:7311 [inline] schedule+0x164/0x2b0 kernel/sched/core.c:7326 schedule_timeout+0x152/0x2c0 kernel/time/sleep_timeout.c:99 rcu_gp_fqs_loop+0x30c/0x11f0 kernel/rcu/tree.c:2123 rcu_gp_kthread+0x9e/0x2b0 kernel/rcu/tree.c:2325 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: CPU: 1 UID: 0 PID: 8207 Comm: kworker/R-bond1 Not tainted syzkaller #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/09/2026 Workqueue: 0x0 (bond1) RIP: 0010:unwind_next_frame+0x722/0x2550 arch/x86/kernel/unwind_orc.c:530 Code: 0f b6 04 20 84 c0 0f 85 ac 17 00 00 49 8d 46 35 88 18 0f b7 1a 83 e3 0f 83 fb 04 0f 8e 84 00 00 00 83 fb 06 0f 8e 87 01 00 00 <83> fb 07 0f 84 c5 02 00 00 83 fb 09 0f 84 b9 0b 00 00 83 fb 0a 0f RSP: 0018:ffffc90000a07a60 EFLAGS: 00000206 RAX: ffffc90000a07b3d RBX: 0000000000000009 RCX: ffffffff90bbf5a0 RDX: ffffffff917040d2 RSI: ffffffff917040b6 RDI: ffffffff8c2a9f20 RBP: ffffc90000a07b40 R08: 000000000000000e R09: 0000000000000000 R10: 0000000000000000 R11: ffffffff8e959c20 R12: dffffc0000000000 R13: ffffffff917040ce R14: ffffc90000a07b08 R15: 1ffff92000140f61 FS: 0000000000000000(0000) GS:ffff888125326000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007ffd9e344d4c CR3: 000000007ff48000 CR4: 00000000003526f0 Call Trace: 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 kasan_save_free_info+0x40/0x50 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:2705 [inline] slab_free mm/slub.c:6405 [inline] kmem_cache_free+0x182/0x650 mm/slub.c:6532 skb_ext_reset include/linux/skbuff.h:5117 [inline] skb_release_head_state+0x270/0x360 net/core/skbuff.c:1183 skb_release_all net/core/skbuff.c:1189 [inline] __kfree_skb+0x24/0x210 net/core/skbuff.c:1205 kfree_skb_reason include/linux/skbuff.h:1323 [inline] kfree_skb include/linux/skbuff.h:1332 [inline] ip6_mc_input+0x909/0xbc0 net/ipv6/ip6_input.c:638 ip_sabotage_in+0x1e1/0x270 net/bridge/br_netfilter_hooks.c:988 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:6206 [inline] __netif_receive_skb net/core/dev.c:6319 [inline] netif_receive_skb_internal net/core/dev.c:6405 [inline] netif_receive_skb+0x278/0xbf0 net/core/dev.c:6464 NF_HOOK+0xa4/0x3a0 include/linux/netfilter.h:318 br_handle_frame_finish+0x1192/0x1990 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+0x90c/0xc40 net/bridge/br_netfilter_ipv6.c:-1 NF_HOOK include/linux/netfilter.h:318 [inline] br_nf_pre_routing_ipv6+0x382/0x6f0 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+0x127f/0x1510 net/bridge/br_input.c:442 __netif_receive_skb_core+0x989/0x30b0 net/core/dev.c:6093 __netif_receive_skb_one_core net/core/dev.c:6204 [inline] __netif_receive_skb net/core/dev.c:6319 [inline] process_backlog+0x706/0x1860 net/core/dev.c:6670 __napi_poll+0xaa/0x330 net/core/dev.c:7729 napi_poll net/core/dev.c:7792 [inline] net_rx_action+0x61d/0xf50 net/core/dev.c:7949 handle_softirqs+0x225/0x840 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:1062 [inline] sysvec_apic_timer_interrupt+0xa6/0xc0 arch/x86/kernel/apic/apic.c:1062 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:674 RIP: 0010:native_irq_enable arch/x86/include/asm/irqflags.h:-1 [inline] RIP: 0010:arch_local_irq_enable arch/x86/include/asm/irqflags.h:119 [inline] RIP: 0010:raw_spin_rq_unlock_irq kernel/sched/sched.h:1673 [inline] RIP: 0010:__schedule+0x1da2/0x56c0 kernel/sched/core.c:7239 Code: 31 f6 e8 21 5b e0 f5 4c 89 ff e8 99 67 e1 f5 0f 1f 44 00 00 49 83 c7 48 4c 89 ff e8 08 c1 01 00 e8 83 12 1a f6 fb 4c 8b 24 24 3a fa ff ff 90 0f 0b 90 f7 c6 01 01 00 00 0f 85 2a e8 ff ff e9 RSP: 0018:ffffc9000563fac0 EFLAGS: 00000202 RAX: 000000000009790b RBX: 1ffff92000ac7f7c RCX: 0000000080000001 RDX: 0000000000000000 RSI: ffffffff8dfe0307 RDI: ffffffff8c2a9f80 RBP: ffffc9000563fca8 R08: ffffffff9032d2f7 R09: 1ffffffff2065a5e R10: dffffc0000000000 R11: fffffbfff2065a5f R12: ffff888050b39f00 R13: dffffc0000000000 R14: ffff888050b39f00 R15: ffff8880b873b148 __schedule_loop kernel/sched/core.c:7311 [inline] schedule+0x164/0x2b0 kernel/sched/core.c:7326 rescuer_thread+0xf45/0x10b0 kernel/workqueue.c:3678 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 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:1c, 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:1c, vlan:0) bridge0: received packet on bridge_slave_1 with own address as source address (addr:aa:aa:aa:aa:aa:1c, vlan:0)