rcu: INFO: rcu_preempt detected stalls on CPUs/tasks: rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P24346/1:b..l rcu: (detected by 1, t=10502 jiffies, g=179665, q=3035 ncpus=2) task:syz.7.4874 state:R running task stack:27144 pid:24346 tgid:24346 ppid:21755 task_flags:0x40044c flags:0x00080003 Call Trace: context_switch kernel/sched/core.c:5510 [inline] __schedule+0x125c/0x6730 kernel/sched/core.c:7234 preempt_schedule_common+0x42/0xc0 kernel/sched/core.c:7413 preempt_schedule_thunk+0x16/0x40 arch/x86/entry/thunk.S:12 __local_bh_enable_ip+0xff/0x120 kernel/softirq.c:457 spin_unlock_bh include/linux/spinlock.h:396 [inline] nl80211_netlink_notify net/wireless/nl80211.c:22960 [inline] nl80211_netlink_notify+0x61c/0x970 net/wireless/nl80211.c:22911 notifier_call_chain+0x99/0x3f0 kernel/notifier.c:85 blocking_notifier_call_chain kernel/notifier.c:380 [inline] blocking_notifier_call_chain+0x69/0xa0 kernel/notifier.c:368 netlink_release+0x167a/0x1ff0 net/netlink/af_netlink.c:762 __sock_release+0xb3/0x260 net/socket.c:710 sock_close+0x1c/0x30 net/socket.c:1501 __fput+0x3ff/0xb50 fs/file_table.c:512 task_work_run+0x150/0x240 kernel/task_work.c:233 exit_task_work include/linux/task_work.h:40 [inline] do_exit+0x951/0x2ae0 kernel/exit.c:1004 do_group_exit+0xd5/0x2a0 kernel/exit.c:1147 get_signal+0x1ec7/0x21e0 kernel/signal.c:3038 arch_do_signal_or_restart+0x91/0x7e0 arch/x86/kernel/signal.c:337 __exit_to_user_mode_loop kernel/entry/common.c:66 [inline] exit_to_user_mode_loop+0x139/0x6f0 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] ret_from_fork+0x932/0xd50 arch/x86/kernel/process.c:167 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 rcu: rcu_preempt kthread starved for 3447 jiffies! g179665 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:27528 pid:16 tgid:16 ppid:2 task_flags:0x208040 flags:0x00080000 Call Trace: context_switch kernel/sched/core.c:5510 [inline] __schedule+0x125c/0x6730 kernel/sched/core.c:7234 __schedule_loop kernel/sched/core.c:7311 [inline] schedule+0xdd/0x2c0 kernel/sched/core.c:7326 schedule_timeout+0x127/0x280 kernel/time/sleep_timeout.c:99 rcu_gp_fqs_loop+0x1a9/0x900 kernel/rcu/tree.c:2123 rcu_gp_kthread+0x179/0x230 kernel/rcu/tree.c:2325 kthread+0x370/0x450 kernel/kthread.c:436 ret_from_fork+0x72b/0xd50 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 1 to CPUs 0: NMI backtrace for cpu 0 CPU: 0 UID: 0 PID: 0 Comm: swapper/0 Tainted: G L syzkaller #0 PREEMPT(full) Tainted: [L]=SOFTLOCKUP Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/09/2026 RIP: 0010:on_stack arch/x86/include/asm/stacktrace.h:55 [inline] RIP: 0010:unwind_next_frame+0x169e/0x2090 arch/x86/kernel/unwind_orc.c:694 Code: c1 ea 03 80 3c 02 00 0f 85 29 06 00 00 49 8d 7d 08 49 8b 5d 38 48 b8 00 00 00 00 00 fc ff df 48 89 fa 48 c1 ea 03 80 3c 02 00 <0f> 85 c1 07 00 00 49 8d 7d 10 49 8b 6d 08 48 b8 00 00 00 00 00 fc RSP: 0018:ffffc900000070e8 EFLAGS: 00000246 RAX: dffffc0000000000 RBX: ffffc90000007718 RCX: ffffffff925f9696 RDX: 1ffff92000000e2c RSI: ffffc900000076e8 RDI: ffffc90000007160 RBP: ffff888035128608 R08: 0000000000000001 R09: 0000000000000007 R10: 0000000000000200 R11: 000000000008f36b R12: ffffc900000071a8 R13: ffffc90000007158 R14: ffffc90000007718 R15: ffffc9000000718c FS: 0000000000000000(0000) GS:ffff888123dec000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f7bb1f556b8 CR3: 00000000ab157000 CR4: 00000000003526f0 Call Trace: arch_stack_walk+0x94/0xf0 arch/x86/kernel/stacktrace.c:25 stack_trace_save+0x8e/0xc0 kernel/stacktrace.c:122 kasan_save_stack+0x30/0x50 mm/kasan/common.c:57 kasan_save_track+0x14/0x30 mm/kasan/common.c:78 kasan_save_free_info+0x3b/0x70 mm/kasan/generic.c:584 poison_slab_object mm/kasan/common.c:253 [inline] __kasan_slab_free+0x5f/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] kfree+0x22b/0x6c0 mm/slub.c:6720 skb_kfree_head net/core/skbuff.c:1077 [inline] skb_free_head+0xb9/0x160 net/core/skbuff.c:1089 skb_release_data+0x6c5/0x8e0 net/core/skbuff.c:1116 skb_release_all net/core/skbuff.c:1191 [inline] __kfree_skb net/core/skbuff.c:1205 [inline] consume_skb net/core/skbuff.c:1439 [inline] consume_skb+0xc4/0x110 net/core/skbuff.c:1433 nft_synproxy_eval_v6 net/netfilter/nft_synproxy.c:91 [inline] nft_synproxy_do_eval+0x919/0xce0 net/netfilter/nft_synproxy.c:145 expr_call_ops_eval net/netfilter/nf_tables_core.c:237 [inline] nft_do_chain+0x2e5/0x19d0 net/netfilter/nf_tables_core.c:285 nft_do_chain_inet+0xf3/0x400 net/netfilter/nft_chain_filter.c:162 nf_hook_entry_hookfn include/linux/netfilter.h:158 [inline] nf_hook_slow+0xbf/0x220 net/netfilter/core.c:619 nf_hook.constprop.0+0x2a6/0x750 include/linux/netfilter.h:273 NF_HOOK include/linux/netfilter.h:316 [inline] ip6_input+0xe0/0x2f0 net/ipv6/ip6_input.c:545 dst_input include/net/dst.h:480 [inline] ip6_rcv_finish net/ipv6/ip6_input.c:119 [inline] NF_HOOK include/linux/netfilter.h:318 [inline] NF_HOOK include/linux/netfilter.h:312 [inline] ipv6_rcv+0x263/0x3d0 net/ipv6/ip6_input.c:351 __netif_receive_skb_one_core+0x12d/0x1e0 net/core/dev.c:6206 __netif_receive_skb+0x1f/0x120 net/core/dev.c:6319 process_backlog+0x37a/0x1580 net/core/dev.c:6670 __napi_poll.constprop.0+0xaf/0x450 net/core/dev.c:7729 napi_poll net/core/dev.c:7792 [inline] net_rx_action+0xa40/0xf20 net/core/dev.c:7949 handle_softirqs+0x1ea/0x9b0 kernel/softirq.c:622 __do_softirq kernel/softirq.c:656 [inline] invoke_softirq kernel/softirq.c:496 [inline] __irq_exit_rcu+0x162/0x210 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+0xa3/0xc0 arch/x86/kernel/apic/apic.c:1062 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:674 RIP: 0010:pv_native_safe_halt+0xf/0x20 arch/x86/kernel/paravirt.c:64 Code: 06 8e 02 c3 cc cc cc cc 0f 1f 00 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 f3 0f 1e fa 66 90 0f 00 2d c3 d9 12 00 fb f4 bc 48 03 00 66 2e 0f 1f 84 00 00 00 00 00 66 90 90 90 90 90 90 RSP: 0018:ffffffff8e807e10 EFLAGS: 00000246 RAX: 0000000006c567c5 RBX: ffffffff8e891480 RCX: ffffffff8bb8c2d5 RDX: 0000000000000000 RSI: ffffffff8e1a29fc RDI: ffffffff8c400c80 RBP: fffffbfff1d12290 R08: 0000000000000001 R09: ffffed101708678d R10: ffff8880b8433c6b R11: 0000000000000000 R12: 0000000000000000 R13: 0000000000000000 R14: 1ffffffff1d00fc6 R15: dffffc0000000000 arch_safe_halt arch/x86/include/asm/paravirt.h:62 [inline] default_idle+0x9/0x10 arch/x86/kernel/process.c:768 default_idle_call+0x6c/0xb0 kernel/sched/idle.c:122 cpuidle_idle_call kernel/sched/idle.c:199 [inline] do_idle+0x3a7/0x5b0 kernel/sched/idle.c:355 cpu_startup_entry+0x4f/0x60 kernel/sched/idle.c:454 rest_init+0x251/0x260 init/main.c:717 start_kernel+0x48e/0x490 init/main.c:1175 x86_64_start_reservations+0x24/0x30 arch/x86/kernel/head64.c:310 x86_64_start_kernel+0x12b/0x130 arch/x86/kernel/head64.c:291 common_startup_64+0x13e/0x158