rcu: INFO: rcu_preempt detected stalls on CPUs/tasks: rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P16462/1:b..l rcu: (detected by 0, t=10505 jiffies, g=65785, q=2318 ncpus=2) task:syz-executor state:R running task stack:22728 pid:16462 tgid:16462 ppid:16459 task_flags:0x400140 flags:0x00080000 Call Trace: context_switch kernel/sched/core.c:5504 [inline] __schedule+0x17d9/0x56c0 kernel/sched/core.c:7228 preempt_schedule_irq+0x4d/0xa0 kernel/sched/core.c:7552 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:bytes_is_nonzero mm/kasan/generic.c:97 [inline] RIP: 0010:memory_is_nonzero mm/kasan/generic.c:115 [inline] RIP: 0010:memory_is_poisoned_n mm/kasan/generic.c:140 [inline] RIP: 0010:memory_is_poisoned mm/kasan/generic.c:172 [inline] RIP: 0010:check_region_inline mm/kasan/generic.c:191 [inline] RIP: 0010:kasan_check_range+0x81/0x2c0 mm/kasan/generic.c:200 Code: ff df 4f 8d 1c 17 49 ff c8 4d 89 c1 49 c1 e9 03 48 bb 01 00 00 00 00 fc ff df 4d 8d 34 19 4d 89 f4 4d 29 dc 49 83 fc 10 7f 29 <4d> 85 e4 0f 84 3d 01 00 00 4c 89 cb 48 f7 d3 4c 01 fb 41 80 3b 00 RSP: 0018:ffffc900038bf410 EFLAGS: 00000283 RAX: ffffffff823cc401 RBX: dffffc0000000001 RCX: ffffffff823cc4ed RDX: 0000000000000000 RSI: 0000000000000004 RDI: ffff88801c42ee9c RBP: 0000000000000000 R08: ffff88801c42ee9f R09: 1ffff11003885dd3 R10: dffffc0000000000 R11: ffffed1003885dd3 R12: 0000000000000001 R13: 0000000000030962 R14: ffffed1003885dd4 R15: 1ffff11003885dd3 instrument_atomic_read include/linux/instrumented.h:82 [inline] atomic_read include/linux/atomic/atomic-instrumented.h:32 [inline] __page_table_check_zero+0x1fd/0x3e0 mm/page_table_check.c:143 page_table_check_free include/linux/page_table_check.h:46 [inline] __free_pages_prepare mm/page_alloc.c:1398 [inline] __free_frozen_pages+0xc1d/0xd20 mm/page_alloc.c:2938 __slab_free+0x274/0x2c0 mm/slub.c:5672 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_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:4610 [inline] slab_alloc_node mm/slub.c:4939 [inline] __do_kmalloc_node mm/slub.c:5333 [inline] __kmalloc_noprof+0x312/0x750 mm/slub.c:5347 _kmalloc_noprof include/linux/slab.h:973 [inline] tomoyo_realpath_from_path+0xef/0x640 security/tomoyo/realpath.c:251 tomoyo_get_realpath security/tomoyo/file.c:151 [inline] tomoyo_check_open_permission+0x229/0x470 security/tomoyo/file.c:776 security_file_open+0xa9/0x240 security/security.c:2739 do_dentry_open+0x4a0/0x1380 fs/open.c:924 vfs_open+0x3b/0x340 fs/open.c:1079 do_open fs/namei.c:4700 [inline] path_openat+0x2e44/0x3830 fs/namei.c:4859 do_file_open+0x23e/0x4a0 fs/namei.c:4888 do_sys_openat2+0x115/0x200 fs/open.c:1395 do_sys_open fs/open.c:1401 [inline] __do_sys_openat fs/open.c:1417 [inline] __se_sys_openat fs/open.c:1412 [inline] __x64_sys_openat+0x138/0x170 fs/open.c:1412 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0x174/0x580 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f9e1ef5d68e RSP: 002b:00007ffdd3206268 EFLAGS: 00000246 ORIG_RAX: 0000000000000101 RAX: ffffffffffffffda RBX: 0000555585282500 RCX: 00007f9e1ef5d68e RDX: 0000000000000002 RSI: 00007ffdd32063b0 RDI: ffffffffffffff9c RBP: 00007ffdd320635c R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00000000000000b6 R13: 00000000000927c0 R14: 000000000004d6c5 R15: 00007ffdd32063b0 rcu: rcu_preempt kthread starved for 1350 jiffies! g65785 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x0 ->cpu=0 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:28040 pid:16 tgid:16 ppid:2 task_flags:0x208040 flags:0x00080000 Call Trace: context_switch kernel/sched/core.c:5504 [inline] __schedule+0x17d9/0x56c0 kernel/sched/core.c:7228 __schedule_loop kernel/sched/core.c:7307 [inline] schedule+0x164/0x360 kernel/sched/core.c:7322 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: 0 UID: 0 PID: 12449 Comm: kworker/0:10 Not tainted syzkaller #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/09/2026 Workqueue: events_long defense_work_handler RIP: 0010:ip6_ignore_linkdown+0x9b/0x140 include/net/addrconf.h:457 Code: 85 ed 74 44 e8 f6 8c 6f f7 48 85 db 0f 84 8a 00 00 00 e8 e8 8c 6f f7 48 81 c3 50 06 00 00 48 89 d8 48 c1 e8 03 42 0f b6 04 30 <84> c0 75 77 8b 1b 31 ff 89 de e8 06 91 6f f7 85 db 0f 95 c0 5b 41 RSP: 0018:ffffc900000068b8 EFLAGS: 00000a06 RAX: 0000000000000000 RBX: ffff888040273650 RCX: ffff888050309f00 RDX: 0000000000000100 RSI: 0000000000000000 RDI: 0000000000000000 RBP: 0000000000000000 R08: ffffc90000006be0 R09: ffffc90000006bf0 R10: ffffc90000006a40 R11: fffff52000000d4a R12: 0000000000000003 R13: ffff8880799af0c8 R14: dffffc0000000000 R15: 0000000000000001 FS: 0000000000000000(0000) GS:ffff88812527c000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00005555945d2a38 CR3: 000000000e746000 CR4: 00000000003526f0 Call Trace: find_match+0x9c/0xb40 net/ipv6/route.c:783 __find_rr_leaf+0x243/0x740 net/ipv6/route.c:872 find_rr_leaf net/ipv6/route.c:893 [inline] rt6_select net/ipv6/route.c:937 [inline] fib6_table_lookup+0x3c6/0xae0 net/ipv6/route.c:2255 ip6_pol_route+0x229/0x14d0 net/ipv6/route.c:2292 pol_lookup_func include/net/ip6_fib.h:669 [inline] fib6_rule_lookup+0x556/0x730 net/ipv6/fib6_rules.c:123 ip6_route_input_lookup net/ipv6/route.c:2363 [inline] ip6_route_input+0x78d/0xb20 net/ipv6/route.c:2666 ip6_rcv_finish+0x141/0x280 net/ipv6/ip6_input.c:117 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+0x76/0xd0 kernel/softirq.c:523 __local_bh_enable_ip+0xf8/0x130 kernel/softirq.c:450 local_bh_enable include/linux/bottom_half.h:33 [inline] update_defense_level+0x867/0xcb0 net/netfilter/ipvs/ip_vs_ctl.c:210 defense_work_handler+0x2d/0xd0 net/netfilter/ipvs/ip_vs_ctl.c:235 process_one_work kernel/workqueue.c:3314 [inline] process_scheduled_works+0xa8e/0x14e0 kernel/workqueue.c:3397 worker_thread+0xa47/0xfb0 kernel/workqueue.c:3478 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: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: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 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)