rcu: INFO: rcu_preempt detected stalls on CPUs/tasks: rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P616/1:b..l rcu: (detected by 1, t=10505 jiffies, g=214857, q=278848 ncpus=2) task:syz.5.7008 state:R running task stack:24680 pid:616 tgid:616 ppid:30260 task_flags:0x400040 flags:0x00080002 Call Trace: context_switch kernel/sched/core.c:5510 [inline] __schedule+0x17d9/0x56c0 kernel/sched/core.c:7234 preempt_schedule_common+0x82/0xd0 kernel/sched/core.c:7413 preempt_schedule_thunk+0x16/0x40 arch/x86/entry/thunk.S:12 __local_bh_enable_ip+0xe1/0x130 kernel/softirq.c:457 nl80211_netlink_notify+0x49c/0x860 net/wireless/nl80211.c:22961 notifier_call_chain+0x1a5/0x3d0 kernel/notifier.c:85 blocking_notifier_call_chain+0x6a/0x90 kernel/notifier.c:380 netlink_release+0x11f8/0x1a80 net/netlink/af_netlink.c:762 __sock_release net/socket.c:710 [inline] sock_close+0xad/0x220 net/socket.c:1501 __fput+0x418/0xa50 fs/file_table.c:512 task_work_run+0x1d9/0x270 kernel/task_work.c:233 resume_user_mode_work include/linux/resume_user_mode.h:50 [inline] __exit_to_user_mode_loop kernel/entry/common.c:70 [inline] exit_to_user_mode_loop+0x1fa/0x730 kernel/entry/common.c:101 __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:230 [inline] syscall_exit_to_user_mode include/linux/entry-common.h:318 [inline] do_syscall_64+0x353/0x580 arch/x86/entry/syscall_64.c:100 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7fa555d9de99 RSP: 002b:00007ffd532fe118 EFLAGS: 00000246 ORIG_RAX: 00000000000001b4 RAX: 0000000000000000 RBX: 00007fa556027da0 RCX: 00007fa555d9de99 RDX: 0000000000000000 RSI: 000000000000001e RDI: 0000000000000003 RBP: 00007fa556027da0 R08: 0000000000000006 R09: 0000000000000000 R10: 00007fa556027cb0 R11: 0000000000000246 R12: 0000000000117fd7 R13: 00007fa55602618c R14: 0000000000117e1f R15: 00007fa556026180 rcu: rcu_preempt kthread starved for 2278 jiffies! g214857 f0x2 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:28104 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: 29555 Comm: kworker/R-bond1 Not tainted syzkaller #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 06/25/2026 Workqueue: bond12 bond_3ad_state_machine_handler RIP: 0010:lock_acquire+0x221/0x350 kernel/locking/lockdep.c:5872 Code: ff ff ff e8 61 8f 2d 0a f7 44 24 08 00 02 00 00 0f 84 3a ff ff ff 65 48 8b 05 4b 9a ca 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 98 ec b8 RSP: 0018:ffffc90000a07f00 EFLAGS: 00000286 RAX: 82bdbd19c9a9ca00 RBX: 0000000000000000 RCX: 0000000000000101 RDX: 00000000a42637f2 RSI: ffffffff8e4b0ad7 RDI: ffffffff8c4bda80 RBP: ffffffff8176f27f R08: ffffffff8176f27f R09: 0000000000000000 R10: 0000000000000000 R11: ffffffff8eb59c60 R12: 0000000000000002 R13: ffffffff8eb59c60 R14: 0000000000000000 R15: 0000000000000246 FS: 0000000000000000(0000) GS:ffff888125054000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 000055555981f4e8 CR3: 0000000030f58000 CR4: 00000000003526f0 Call Trace: rcu_lock_acquire include/linux/rcupdate.h:300 [inline] rcu_read_lock include/linux/rcupdate.h:840 [inline] class_rcu_constructor include/linux/rcupdate.h:1183 [inline] unwind_next_frame+0xac/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 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 nft_synproxy_eval_v4+0x36a/0x4e0 net/netfilter/nft_synproxy.c:-1 nft_synproxy_do_eval+0x335/0x550 net/netfilter/nft_synproxy.c:141 expr_call_ops_eval net/netfilter/nf_tables_core.c:237 [inline] nft_do_chain+0x48d/0x1b10 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 NF_HOOK+0x336/0x3c0 include/linux/netfilter.h:318 __netif_receive_skb_one_core net/core/dev.c:6212 [inline] __netif_receive_skb net/core/dev.c:6325 [inline] process_backlog+0xa34/0x1860 net/core/dev.c:6676 __napi_poll+0xaa/0x330 net/core/dev.c:7735 napi_poll net/core/dev.c:7798 [inline] net_rx_action+0x61d/0xf50 net/core/dev.c:7955 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:__schedule+0x80/0x56c0 kernel/sched/core.c:7062 Code: ed 98 47 8e 48 c7 84 24 30 01 00 00 30 8e d0 8b 4c 8d b4 24 20 01 00 00 49 c1 ee 03 48 b8 f1 f1 f1 f1 f8 f8 f8 f2 4b 89 04 2e <48> b8 f2 f2 f2 f2 f8 f8 f3 f3 4b 89 44 2e 08 66 43 c7 44 2e 0c 00 RSP: 0018:ffffc900046cf680 EFLAGS: 00000a02 RAX: f2f8f8f8f1f1f1f1 RBX: ffffffff81336f16 RCX: 0000000000000000 RDX: 0000000000000006 RSI: ffffffff8e22b815 RDI: ffffc900046cf800 RBP: ffffc900046cf880 R08: ffffffff905784f7 R09: 1ffffffff20af09e R10: dffffc0000000000 R11: fffffbfff20af09f R12: ffff888037262d18 R13: dffffc0000000000 R14: 1ffff920008d9ef4 R15: dffffc0000000000 preempt_schedule_common+0x82/0xd0 kernel/sched/core.c:7413 preempt_schedule_thunk+0x16/0x40 arch/x86/entry/thunk.S:12 __local_bh_enable_ip+0xe1/0x130 kernel/softirq.c:457 spin_unlock_bh include/linux/spinlock.h:396 [inline] bond_3ad_state_machine_handler+0x5a7c/0x5d60 drivers/net/bonding/bond_3ad.c:2618 process_one_work kernel/workqueue.c:3322 [inline] process_scheduled_works+0xa8e/0x14e0 kernel/workqueue.c:3405 rescuer_thread+0x7b6/0x10b0 kernel/workqueue.c:3629 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