rcu: INFO: rcu_preempt detected stalls on CPUs/tasks: rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P28857/1:b..l rcu: (detected by 1, t=10502 jiffies, g=171845, q=1107 ncpus=2) task:syz-executor state:R running task stack:20952 pid:28857 tgid:28857 ppid:28847 task_flags:0x400140 flags:0x00080000 Call Trace: context_switch kernel/sched/core.c:5387 [inline] __schedule+0x17b4/0x5680 kernel/sched/core.c:7188 preempt_schedule_irq+0x4d/0xa0 kernel/sched/core.c:7512 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:lock_acquire+0x221/0x350 kernel/locking/lockdep.c:5872 Code: ff ff ff e8 a1 17 17 0a f7 44 24 08 00 02 00 00 0f 84 3a ff ff ff 65 48 8b 05 8b 02 9f 11 48 3b 44 24 58 75 33 fb 48 83 c4 60 <5b> 41 5c 41 5d 41 5e 41 5f 5d c3 cc cc cc cc cc 48 8d 3d d8 11 95 RSP: 0018:ffffc900059fefd8 EFLAGS: 00000286 RAX: 15e9fa7271c23b00 RBX: 0000000000000000 RCX: 0000000000000046 RDX: 000000004c643b95 RSI: ffffffff8e24f3ee RDI: ffffffff8c289f60 RBP: ffffffff81771256 R08: ffffffff81771256 R09: ffffffff8e95cce0 R10: ffffc900059ff138 R11: ffffffff81b105c0 R12: 0000000000000002 R13: ffffffff8e95cce0 R14: 0000000000000000 R15: 0000000000000246 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 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_frozen_pages+0xbc7/0xd30 mm/page_alloc.c:2943 __slab_free+0x274/0x2c0 mm/slub.c:5608 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:4569 [inline] slab_alloc_node mm/slub.c:4898 [inline] __do_kmalloc_node mm/slub.c:5294 [inline] __kmalloc_noprof+0x316/0x760 mm/slub.c:5307 kmalloc_noprof include/linux/slab.h:954 [inline] tomoyo_realpath_from_path+0xe3/0x5d0 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+0x384/0x14e0 fs/open.c:924 vfs_open+0x3b/0x340 fs/open.c:1079 do_open fs/namei.c:4699 [inline] path_openat+0x2e08/0x3860 fs/namei.c:4858 do_file_open+0x23e/0x4a0 fs/namei.c:4887 do_sys_openat2+0x113/0x200 fs/open.c:1364 do_sys_open fs/open.c:1370 [inline] __do_sys_openat fs/open.c:1386 [inline] __se_sys_openat fs/open.c:1381 [inline] __x64_sys_openat+0x138/0x170 fs/open.c:1381 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: 0033:0x7f258435d60e RSP: 002b:00007fff067c7328 EFLAGS: 00000246 ORIG_RAX: 0000000000000101 RAX: ffffffffffffffda RBX: 000055555a879500 RCX: 00007f258435d60e RDX: 0000000000000002 RSI: 00007fff067c7470 RDI: ffffffffffffff9c RBP: 00007fff067c741c R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000080 R13: 0000000000000063 R14: 00000000000e62b2 R15: 00007fff067c7470 rcu: rcu_preempt kthread starved for 7763 jiffies! g171845 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:27536 pid:16 tgid:16 ppid:2 task_flags:0x208040 flags:0x00080000 Call Trace: context_switch kernel/sched/core.c:5387 [inline] __schedule+0x17b4/0x5680 kernel/sched/core.c:7188 __schedule_loop kernel/sched/core.c:7267 [inline] schedule+0x164/0x360 kernel/sched/core.c:7282 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: CPU: 1 UID: 0 PID: 19062 Comm: kworker/R-bond1 Not tainted syzkaller #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/18/2026 Workqueue: bond1 bond_alb_monitor RIP: 0010:rcu_read_unlock include/linux/rcupdate.h:867 [inline] RIP: 0010:class_rcu_destructor include/linux/rcupdate.h:1181 [inline] RIP: 0010:unwind_next_frame+0x1b76/0x2550 arch/x86/kernel/unwind_orc.c:709 Code: 4c 8b 6c 24 20 41 0f b6 44 2d 00 84 c0 0f 85 81 02 00 00 41 c7 06 00 00 00 00 31 db e8 73 bd 41 0a 85 c0 74 3a e8 ca c6 33 00 <84> c0 75 31 e8 61 bd 41 0a 85 c0 74 28 80 3d e4 1a a6 0e 00 75 1f RSP: 0018:ffffc90000a07e18 EFLAGS: 00000202 RAX: 0000000000000001 RBX: ffffffff90d6a501 RCX: 0000000080000102 RDX: ffffc90000a07f01 RSI: ffffffff8c289f40 RDI: ffffffff8c289f00 RBP: dffffc0000000000 R08: ffffc90000a08280 R09: 0000000000000000 R10: ffffc90000a07f38 R11: fffff52000140fe9 R12: ffffc90000a08290 R13: ffffc90000a01000 R14: ffffc90000a07ee8 R15: ffffffff81771256 FS: 0000000000000000(0000) GS:ffff888125313000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 000055558bd049e8 CR3: 000000007d88c000 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+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:6246 [inline] kfree+0x1c5/0x640 mm/slub.c:6561 skb_kfree_head net/core/skbuff.c:1075 [inline] skb_free_head net/core/skbuff.c:1087 [inline] skb_release_data+0x828/0xa60 net/core/skbuff.c:1114 skb_release_all net/core/skbuff.c:1189 [inline] __kfree_skb+0x5d/0x210 net/core/skbuff.c:1203 nft_synproxy_eval_v6+0x352/0x4e0 net/netfilter/nft_synproxy.c:92 nft_synproxy_do_eval+0x3ce/0x580 net/netfilter/nft_synproxy.c:146 expr_call_ops_eval net/netfilter/nf_tables_core.c:237 [inline] nft_do_chain+0x467/0x19f0 net/netfilter/nf_tables_core.c:285 nft_do_chain_inet+0x360/0x4b0 net/netfilter/nft_chain_filter.c:162 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 ip6_input+0x16a/0x270 net/ipv6/ip6_input.c:540 NF_HOOK+0x336/0x3c0 include/linux/netfilter.h:318 __netif_receive_skb_one_core net/core/dev.c:6209 [inline] __netif_receive_skb net/core/dev.c:6322 [inline] process_backlog+0x7dd/0x1950 net/core/dev.c:6673 __napi_poll+0xae/0x340 net/core/dev.c:7737 napi_poll net/core/dev.c:7800 [inline] net_rx_action+0x627/0xf70 net/core/dev.c:7957 handle_softirqs+0x22a/0x840 kernel/softirq.c:622 do_softirq+0x76/0xd0 kernel/softirq.c:523 __local_bh_enable_ip+0xf8/0x130 kernel/softirq.c:450 spin_unlock_bh include/linux/spinlock.h:396 [inline] tlb_clear_slave drivers/net/bonding/bond_alb.c:121 [inline] bond_alb_monitor+0x7a7/0x17e0 drivers/net/bonding/bond_alb.c:1572 process_one_work kernel/workqueue.c:3302 [inline] process_scheduled_works+0xb5d/0x1860 kernel/workqueue.c:3385 rescuer_thread+0x827/0x1130 kernel/workqueue.c:3609 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