rcu: INFO: rcu_preempt detected stalls on CPUs/tasks: rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P15270/1:b..l rcu: (detected by 0, t=10502 jiffies, g=52977, q=327 ncpus=2) task:syz.4.2186 state:R running task stack:26280 pid:15270 tgid:15270 ppid:5838 task_flags:0x400040 flags:0x00004004 Call Trace: context_switch kernel/sched/core.c:5397 [inline] __schedule+0x116a/0x5dd0 kernel/sched/core.c:6786 preempt_schedule_irq+0x51/0x90 kernel/sched/core.c:7109 irqentry_exit+0x36/0x90 kernel/entry/common.c:307 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702 RIP: 0010:__reset_page_owner+0x5f/0x1a0 mm/page_owner.c:299 Code: 89 c3 e8 44 94 90 ff 4c 8b 3d 0d 16 50 0c 48 b8 00 00 00 00 00 fc ff df 49 01 df 49 8d 7f 08 48 89 fa 48 c1 ea 03 0f b6 04 02 <84> c0 74 08 3c 03 0f 8e 2a 01 00 00 48 89 df 45 8b 7f 08 0f b7 dd RSP: 0018:ffffc9000511f8b0 EFLAGS: 00000a06 RAX: 0000000000000000 RBX: ffff88801d978cc0 RCX: ffffffff822cd3cb RDX: 1ffff11003b2f19a RSI: ffffffff822b544c RDI: ffff88801d978cd0 RBP: 0000000000000002 R08: 0000000000000007 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000001 R12: ffffea0000f2d700 R13: 000000a056c6026c R14: 0000000000000002 R15: ffff88801d978cc8 reset_page_owner include/linux/page_owner.h:25 [inline] free_pages_prepare mm/page_alloc.c:1248 [inline] __free_frozen_pages+0x7fe/0x1180 mm/page_alloc.c:2706 qlink_free mm/kasan/quarantine.c:163 [inline] qlist_free_all+0x4d/0x120 mm/kasan/quarantine.c:179 kasan_quarantine_reduce+0x195/0x1e0 mm/kasan/quarantine.c:286 __kasan_kmalloc+0x8a/0xb0 mm/kasan/common.c:385 kasan_kmalloc include/linux/kasan.h:260 [inline] __do_kmalloc_node mm/slub.c:4328 [inline] __kmalloc_noprof+0x223/0x510 mm/slub.c:4340 kmalloc_noprof include/linux/slab.h:909 [inline] kzalloc_noprof include/linux/slab.h:1039 [inline] lsm_blob_alloc+0x68/0x90 security/security.c:684 lsm_task_alloc security/security.c:771 [inline] security_task_alloc+0x2d/0x260 security/security.c:3160 copy_process+0x2205/0x7650 kernel/fork.c:2151 kernel_clone+0xfc/0x960 kernel/fork.c:2599 __do_sys_clone3+0x212/0x290 kernel/fork.c:2903 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xcd/0x4c0 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f1b723c3209 RSP: 002b:00007ffd1dcdcd38 EFLAGS: 00000206 ORIG_RAX: 00000000000001b3 RAX: ffffffffffffffda RBX: 00007f1b72345600 RCX: 00007f1b723c3209 RDX: 00007f1b72345600 RSI: 0000000000000058 RDI: 00007ffd1dcdcd80 RBP: 00007f1b732756c0 R08: 00007f1b732756c0 R09: 00007ffd1dcdce67 R10: 0000000000000008 R11: 0000000000000206 R12: ffffffffffffffa8 R13: 000000000000006e R14: 00007ffd1dcdcd80 R15: 00007ffd1dcdce68 rcu: rcu_preempt kthread starved for 1170 jiffies! g52977 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:I stack:27784 pid:16 tgid:16 ppid:2 task_flags:0x208040 flags:0x00004000 Call Trace: context_switch kernel/sched/core.c:5397 [inline] __schedule+0x116a/0x5dd0 kernel/sched/core.c:6786 __schedule_loop kernel/sched/core.c:6864 [inline] schedule+0xe7/0x3a0 kernel/sched/core.c:6879 schedule_timeout+0x123/0x290 kernel/time/sleep_timeout.c:99 rcu_gp_fqs_loop+0x1ea/0xb00 kernel/rcu/tree.c:2054 rcu_gp_kthread+0x270/0x380 kernel/rcu/tree.c:2256 kthread+0x3c2/0x780 kernel/kthread.c:464 ret_from_fork+0x5d4/0x6f0 arch/x86/kernel/process.c:148 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 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 UID: 0 PID: 5976 Comm: kworker/1:8 Not tainted 6.16.0-rc7-syzkaller-00120-g5f33ebd2018c #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025 Workqueue: wg-kex-wg2 wg_packet_handshake_receive_worker RIP: 0010:stack_trace_consume_entry+0xaf/0x170 kernel/stacktrace.c:93 Code: c0 03 38 d0 7c 08 84 d2 0f 85 98 00 00 00 8b 43 0c 85 c0 75 57 48 b8 00 00 00 00 00 fc ff df 48 89 da 48 c1 ea 03 80 3c 02 00 <0f> 85 9a 00 00 00 8d 45 01 89 43 10 48 8b 03 48 8d 2c e8 48 b8 00 RSP: 0018:ffffc90000a08058 EFLAGS: 00000246 RAX: dffffc0000000000 RBX: ffffc90000a08138 RCX: ffffc90000a07fcc RDX: 1ffff92000141027 RSI: ffffffff8962aebf RDI: ffffc90000a08144 RBP: 0000000000000011 R08: 0000000000000001 R09: 0000000000000000 R10: 0000000000000000 R11: 000000000008629f R12: ffffffff81a78d10 R13: ffffc90000a08138 R14: 0000000000000000 R15: ffff888036480000 FS: 0000000000000000(0000) GS:ffff888124820000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007ffe26061840 CR3: 0000000029113000 CR4: 00000000003526f0 Call Trace: arch_stack_walk+0x85/0x100 arch/x86/kernel/stacktrace.c:27 stack_trace_save+0x8e/0xc0 kernel/stacktrace.c:122 kasan_save_stack+0x33/0x60 mm/kasan/common.c:47 kasan_save_track+0x14/0x30 mm/kasan/common.c:68 unpoison_slab_object mm/kasan/common.c:319 [inline] __kasan_slab_alloc+0x89/0x90 mm/kasan/common.c:345 kasan_slab_alloc include/linux/kasan.h:250 [inline] slab_post_alloc_hook mm/slub.c:4148 [inline] slab_alloc_node mm/slub.c:4197 [inline] kmem_cache_alloc_node_noprof+0x1d5/0x3b0 mm/slub.c:4249 __alloc_skb+0x2b2/0x380 net/core/skbuff.c:660 alloc_skb include/linux/skbuff.h:1336 [inline] synproxy_send_client_synack+0x1af/0x8f0 net/netfilter/nf_synproxy_core.c:460 nft_synproxy_eval_v4 net/netfilter/nft_synproxy.c:59 [inline] nft_synproxy_do_eval+0xa63/0xd80 net/netfilter/nft_synproxy.c:141 expr_call_ops_eval net/netfilter/nf_tables_core.c:237 [inline] nft_do_chain+0x2e6/0x1920 net/netfilter/nf_tables_core.c:285 nft_do_chain_inet+0x18a/0x340 net/netfilter/nft_chain_filter.c:161 nf_hook_entry_hookfn include/linux/netfilter.h:157 [inline] nf_hook_slow+0xbb/0x200 net/netfilter/core.c:623 nf_hook.constprop.0+0x422/0x750 include/linux/netfilter.h:272 NF_HOOK include/linux/netfilter.h:315 [inline] ip_local_deliver+0x169/0x1f0 net/ipv4/ip_input.c:254 dst_input include/net/dst.h:469 [inline] ip_rcv_finish net/ipv4/ip_input.c:448 [inline] NF_HOOK include/linux/netfilter.h:317 [inline] NF_HOOK include/linux/netfilter.h:311 [inline] ip_rcv+0x2c3/0x5d0 net/ipv4/ip_input.c:568 __netif_receive_skb_one_core+0x197/0x1e0 net/core/dev.c:5977 __netif_receive_skb+0x1d/0x160 net/core/dev.c:6090 process_backlog+0x442/0x15e0 net/core/dev.c:6442 __napi_poll.constprop.0+0xb7/0x550 net/core/dev.c:7414 napi_poll net/core/dev.c:7478 [inline] net_rx_action+0xa9f/0xfe0 net/core/dev.c:7605 handle_softirqs+0x219/0x8e0 kernel/softirq.c:579 do_softirq kernel/softirq.c:480 [inline] do_softirq+0xb2/0xf0 kernel/softirq.c:467 __local_bh_enable_ip+0x100/0x120 kernel/softirq.c:407 local_bh_enable include/linux/bottom_half.h:33 [inline] rcu_read_unlock_bh include/linux/rcupdate.h:910 [inline] wg_pubkey_hashtable_lookup+0x1b0/0x3f0 drivers/net/wireguard/peerlookup.c:69 wg_noise_handshake_consume_initiation+0x452/0x880 drivers/net/wireguard/noise.c:617 wg_receive_handshake_packet+0x219/0xbf0 drivers/net/wireguard/receive.c:144 wg_packet_handshake_receive_worker+0x17f/0x3a0 drivers/net/wireguard/receive.c:213 process_one_work+0x9cc/0x1b70 kernel/workqueue.c:3238 process_scheduled_works kernel/workqueue.c:3321 [inline] worker_thread+0x6c8/0xf10 kernel/workqueue.c:3402 kthread+0x3c2/0x780 kernel/kthread.c:464 ret_from_fork+0x5d4/0x6f0 arch/x86/kernel/process.c:148 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245