GRED: Unable to relocate VQ 0x0 after dequeue, screwing up backlog ip6_tunnel: ip6gre1 xmit: Local address not yet configured! rcu: INFO: rcu_preempt detected stalls on CPUs/tasks: rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P17452/1:b..l rcu: (detected by 1, t=10503 jiffies, g=57453, q=595636 ncpus=2) task:syz-executor state:R running task stack:21384 pid:17452 tgid:17452 ppid:1 task_flags:0x40054c flags:0x00004004 Call Trace: context_switch kernel/sched/core.c:5357 [inline] __schedule+0x1798/0x4cc0 kernel/sched/core.c:6961 preempt_schedule_irq+0xb5/0x150 kernel/sched/core.c:7288 irqentry_exit+0x6f/0x90 kernel/entry/common.c:197 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702 RIP: 0010:on_stack arch/x86/include/asm/stacktrace.h:58 [inline] RIP: 0010:stack_access_ok arch/x86/kernel/unwind_orc.c:393 [inline] RIP: 0010:deref_stack_reg arch/x86/kernel/unwind_orc.c:403 [inline] RIP: 0010:unwind_next_frame+0xb56/0x2390 arch/x86/kernel/unwind_orc.c:585 Code: ff df 48 8b 4c 24 20 0f b6 04 01 84 c0 0f 85 85 13 00 00 41 83 3e 00 0f 95 c0 49 39 df 0f 96 c1 20 c1 49 39 dc 0f 97 c0 20 c8 <3c> 01 75 18 48 8d 43 08 4c 39 f8 0f 97 c1 4c 39 e0 0f 96 c0 84 c1 RSP: 0018:ffffc90003f1f1f8 EFLAGS: 00000202 RAX: 0000000000000001 RBX: ffffc90003f1fa18 RCX: 1ffff920007e3e01 RDX: ffffffff9034014c RSI: 0000000000000002 RDI: ffffffff8be33ba0 RBP: 1ffff920007e3e5a R08: 0000000000000001 R09: ffffffff8172d195 R10: ffffc90003f1f318 R11: ffffffff81ac4b00 R12: ffffc90003f20000 R13: 1ffff920007e3e5b R14: ffffc90003f1f2c8 R15: ffffc90003f18000 arch_stack_walk+0x11c/0x150 arch/x86/kernel/stacktrace.c:25 stack_trace_save+0x9c/0xe0 kernel/stacktrace.c:122 kasan_save_stack+0x3e/0x60 mm/kasan/common.c:47 kasan_record_aux_stack+0xbd/0xd0 mm/kasan/generic.c:548 __call_rcu_common kernel/rcu/tree.c:3123 [inline] call_rcu+0x157/0x9c0 kernel/rcu/tree.c:3243 slab_free_hook mm/slub.c:2386 [inline] slab_free mm/slub.c:4695 [inline] kmem_cache_free+0x309/0x400 mm/slub.c:4797 exit_mmap+0x53f/0xb50 mm/mmap.c:1305 __mmput+0x118/0x430 kernel/fork.c:1129 exit_mm+0x1da/0x2c0 kernel/exit.c:582 do_exit+0x648/0x2300 kernel/exit.c:949 do_group_exit+0x21c/0x2d0 kernel/exit.c:1102 get_signal+0x1286/0x1340 kernel/signal.c:3034 arch_do_signal_or_restart+0x9a/0x750 arch/x86/kernel/signal.c:337 exit_to_user_mode_loop+0x75/0x110 kernel/entry/common.c:40 exit_to_user_mode_prepare include/linux/irq-entry-common.h:225 [inline] syscall_exit_to_user_mode_work include/linux/entry-common.h:175 [inline] syscall_exit_to_user_mode include/linux/entry-common.h:210 [inline] do_syscall_64+0x2bd/0x3b0 arch/x86/entry/syscall_64.c:100 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f4ba0384e17 RSP: 002b:00007ffc6f458450 EFLAGS: 00000293 ORIG_RAX: 000000000000003d RAX: fffffffffffffe00 RBX: 000000000000007b RCX: 00007f4ba0384e17 RDX: 0000000040000000 RSI: 00007ffc6f4584bc RDI: 00000000ffffffff RBP: 00007ffc6f4584bc R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000293 R12: 0000000000000028 R13: 000055557df7c590 R14: 0000000000050832 R15: 00007ffc6f458510 rcu: rcu_preempt kthread starved for 945 jiffies! g57453 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:27160 pid:16 tgid:16 ppid:2 task_flags:0x208040 flags:0x00004000 Call Trace: context_switch kernel/sched/core.c:5357 [inline] __schedule+0x1798/0x4cc0 kernel/sched/core.c:6961 __schedule_loop kernel/sched/core.c:7043 [inline] schedule+0x165/0x360 kernel/sched/core.c:7058 schedule_timeout+0x12b/0x270 kernel/time/sleep_timeout.c:99 rcu_gp_fqs_loop+0x301/0x1540 kernel/rcu/tree.c:2083 rcu_gp_kthread+0x99/0x390 kernel/rcu/tree.c:2285 kthread+0x70e/0x8a0 kernel/kthread.c:463 ret_from_fork+0x436/0x7d0 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: CPU: 1 UID: 0 PID: 9419 Comm: kworker/u8:18 Not tainted syzkaller #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/18/2025 Workqueue: wg-kex-wg2 wg_packet_handshake_send_worker RIP: 0010:__rcu_read_unlock+0x0/0xe0 kernel/rcu/tree_plugin.h:431 Code: 89 d9 80 e1 07 80 c1 03 38 c1 7c dc 48 89 df e8 96 07 7c 00 eb d2 0f 1f 40 00 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 0f 1e fa 41 57 41 56 41 55 41 54 53 49 bf 00 00 00 00 00 fc ff RSP: 0018:ffffc90000a076b0 EFLAGS: 00000282 RAX: e7795c26d3fc2400 RBX: ffffffff90c0a301 RCX: e7795c26d3fc2400 RDX: 0000000000000007 RSI: ffffffff8dba91be RDI: ffffffff8be33c00 RBP: dffffc0000000000 R08: ffffc90000a08370 R09: 0000000000000000 R10: ffffc90000a077d8 R11: fffff52000140efd R12: ffffc90000a08380 R13: ffffc90000a01000 R14: ffffc90000a07788 R15: ffffffff8172d195 FS: 0000000000000000(0000) GS:ffff888125d15000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 000055558387d5c8 CR3: 0000000074416000 CR4: 00000000003526f0 Call Trace: rcu_read_unlock include/linux/rcupdate.h:873 [inline] class_rcu_destructor include/linux/rcupdate.h:1155 [inline] unwind_next_frame+0x19ae/0x2390 arch/x86/kernel/unwind_orc.c:680 arch_stack_walk+0x11c/0x150 arch/x86/kernel/stacktrace.c:25 stack_trace_save+0x9c/0xe0 kernel/stacktrace.c:122 kasan_save_stack mm/kasan/common.c:47 [inline] kasan_save_track+0x3e/0x80 mm/kasan/common.c:68 poison_kmalloc_redzone mm/kasan/common.c:388 [inline] __kasan_kmalloc+0x93/0xb0 mm/kasan/common.c:405 kasan_kmalloc include/linux/kasan.h:260 [inline] __kmalloc_cache_noprof+0x230/0x3d0 mm/slub.c:4407 kmalloc_noprof include/linux/slab.h:905 [inline] kzalloc_noprof include/linux/slab.h:1039 [inline] ref_tracker_alloc+0x133/0x460 lib/ref_tracker.c:271 __netdev_tracker_alloc include/linux/netdevice.h:4349 [inline] netdev_hold include/linux/netdevice.h:4378 [inline] dst_init+0xd9/0x450 net/core/dst.c:52 dst_alloc+0x12a/0x170 net/core/dst.c:93 rt_dst_alloc net/ipv4/route.c:1645 [inline] __mkroute_output net/ipv4/route.c:2649 [inline] ip_route_output_key_hash_rcu+0x1560/0x23e0 net/ipv4/route.c:2870 ip_route_output_key_hash+0x1b9/0x2e0 net/ipv4/route.c:2700 __ip_route_output_key include/net/route.h:169 [inline] ip_route_output_flow+0x2a/0x150 net/ipv4/route.c:2927 ip_route_output_key include/net/route.h:179 [inline] ip_route_me_harder+0x6d2/0x1030 net/ipv4/netfilter.c:53 synproxy_send_tcp+0x359/0x6c0 net/netfilter/nf_synproxy_core.c:431 synproxy_send_client_synack+0x8bb/0xe20 net/netfilter/nf_synproxy_core.c:484 nft_synproxy_eval_v4+0x36e/0x560 net/netfilter/nft_synproxy.c:59 nft_synproxy_do_eval+0x345/0x570 net/netfilter/nft_synproxy.c:141 expr_call_ops_eval net/netfilter/nf_tables_core.c:237 [inline] nft_do_chain+0x40c/0x1920 net/netfilter/nf_tables_core.c:285 nft_do_chain_inet+0x25d/0x340 net/netfilter/nft_chain_filter.c:161 nf_hook_entry_hookfn include/linux/netfilter.h:158 [inline] nf_hook_slow+0xc5/0x220 net/netfilter/core.c:623 nf_hook include/linux/netfilter.h:273 [inline] NF_HOOK+0x206/0x3a0 include/linux/netfilter.h:316 NF_HOOK+0x309/0x3a0 include/linux/netfilter.h:318 __netif_receive_skb_one_core net/core/dev.c:5991 [inline] __netif_receive_skb+0x143/0x380 net/core/dev.c:6104 process_backlog+0x60e/0x14f0 net/core/dev.c:6456 __napi_poll+0xc4/0x360 net/core/dev.c:7506 napi_poll net/core/dev.c:7569 [inline] net_rx_action+0x707/0xe30 net/core/dev.c:7696 handle_softirqs+0x283/0x870 kernel/softirq.c:579 do_softirq+0xec/0x180 kernel/softirq.c:480 __local_bh_enable_ip+0x17d/0x1c0 kernel/softirq.c:407 local_bh_enable include/linux/bottom_half.h:33 [inline] fpregs_unlock arch/x86/include/asm/fpu/api.h:77 [inline] kernel_fpu_end+0xd2/0x120 arch/x86/kernel/fpu/core.c:479 blake2s_compress+0x5f/0xd0 lib/crypto/x86/blake2s-glue.c:46 blake2s_update+0x14b/0x450 lib/crypto/blake2s.c:33 hmac+0x1b6/0x330 drivers/net/wireguard/noise.c:324 kdf drivers/net/wireguard/noise.c:367 [inline] message_ephemeral+0x1e2/0x280 drivers/net/wireguard/noise.c:493 wg_noise_handshake_create_initiation+0x27c/0x7e0 drivers/net/wireguard/noise.c:545 wg_packet_send_handshake_initiation drivers/net/wireguard/send.c:34 [inline] wg_packet_handshake_send_worker+0x163/0x320 drivers/net/wireguard/send.c:51 process_one_work kernel/workqueue.c:3236 [inline] process_scheduled_works+0xae1/0x17b0 kernel/workqueue.c:3319 worker_thread+0x8a0/0xda0 kernel/workqueue.c:3400 kthread+0x70e/0x8a0 kernel/kthread.c:463 ret_from_fork+0x436/0x7d0 arch/x86/kernel/process.c:148 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245