rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 	1-...!: (3 ticks this GP) idle=2a04/1/0x4000000000000000 softirq=21968/21968 fqs=0
rcu: 	(detected by 0, t=10502 jiffies, g=15677, q=1071 ncpus=2)
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 6440 Comm: napi/wg2-0 Not tainted syzkaller #0 PREEMPT(full) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/18/2025
RIP: 0010:do_raw_spin_lock+0x2c/0x290 kernel/locking/spinlock_debug.c:114
Code: 1e fa 55 48 89 e5 41 57 41 56 41 55 41 54 53 48 83 e4 e0 48 81 ec 80 00 00 00 48 89 fb 65 48 8b 05 e9 2d 23 11 48 89 44 24 60 <49> bf 00 00 00 00 00 fc ff df 48 c7 44 24 20 b3 8a b5 41 48 c7 44
RSP: 0018:ffffc90000a08be0 EFLAGS: 00000082
RAX: a264876bf5a01700 RBX: ffff8880b8727ac0 RCX: a264876bf5a01700
RDX: 0000000000000000 RSI: ffffffff8dd8c626 RDI: ffff8880b8727ac0
RBP: ffffc90000a08c90 R08: 0000000000000000 R09: ffffffff81ae5162
R10: dffffc0000000000 R11: fffffbfff1f8680f R12: ffff888033a07340
R13: dffffc0000000000 R14: 1ffff92000141194 R15: dffffc0000000000
FS:  0000000000000000(0000) GS:ffff888125b03000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000200000000600 CR3: 0000000071130000 CR4: 00000000003526f0
Call Trace:
 <IRQ>
 __raw_spin_lock_irq include/linux/spinlock_api_smp.h:120 [inline]
 _raw_spin_lock_irq+0xae/0xf0 kernel/locking/spinlock.c:170
 __run_hrtimer kernel/time/hrtimer.c:1781 [inline]
 __hrtimer_run_queues+0x602/0xc60 kernel/time/hrtimer.c:1841
 hrtimer_interrupt+0x45b/0xaa0 kernel/time/hrtimer.c:1903
 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1041 [inline]
 __sysvec_apic_timer_interrupt+0x10b/0x410 arch/x86/kernel/apic/apic.c:1058
 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1052 [inline]
 sysvec_apic_timer_interrupt+0xa1/0xc0 arch/x86/kernel/apic/apic.c:1052
 </IRQ>
 <TASK>
 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:697
RIP: 0010:trace_kfree_skb+0x0/0x200 include/trace/events/skb.h:24
Code: f8 48 89 df 5b e9 60 50 21 00 e8 7b 6e 58 f8 5b e9 45 3c 19 02 cc 0f 1f 40 00 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 <55> 41 57 41 56 41 55 41 54 53 48 89 cb 89 d5 49 89 f6 49 89 ff e8
RSP: 0018:ffffc900036b7188 EFLAGS: 00000293
RAX: ffffffff896471fe RBX: ffff888071031140 RCX: 0000000000000000
RDX: 0000000000000002 RSI: ffffffff8a37763e RDI: ffff888071031140
RBP: 00000000fffd0002 R08: ffff888071031227 R09: 1ffff1100e206244
R10: dffffc0000000000 R11: ffffed100e206245 R12: ffff888071031224
R13: ffff888058ba6ae8 R14: 0000000000000002 R15: 0000000000000000
 __sk_skb_reason_drop net/core/skbuff.c:1186 [inline]
 sk_skb_reason_drop+0xe1/0x170 net/core/skbuff.c:1203
 kfree_skb_reason include/linux/skbuff.h:1316 [inline]
 kfree_skb include/linux/skbuff.h:1325 [inline]
 ip6_mc_input+0x8de/0xb70 net/ipv6/ip6_input.c:593
 dst_input include/net/dst.h:474 [inline]
 ip6_sublist_rcv_finish+0x272/0x2a0 net/ipv6/ip6_input.c:88
 ip6_list_rcv_finish net/ipv6/ip6_input.c:145 [inline]
 ip6_sublist_rcv+0xb11/0xdd0 net/ipv6/ip6_input.c:321
 ipv6_list_rcv+0x3e5/0x430 net/ipv6/ip6_input.c:355
 __netif_receive_skb_list_ptype net/core/dev.c:6115 [inline]
 __netif_receive_skb_list_core+0x5f4/0x800 net/core/dev.c:6162
 __netif_receive_skb_list net/core/dev.c:6214 [inline]
 netif_receive_skb_list_internal+0x96f/0xcb0 net/core/dev.c:6305
 gro_normal_list include/net/gro.h:532 [inline]
 gro_flush_normal include/net/gro.h:540 [inline]
 napi_complete_done+0x2f2/0x7c0 net/core/dev.c:6674
 wg_packet_rx_poll+0x2413/0x24a0 drivers/net/wireguard/receive.c:488
 __napi_poll+0xc7/0x360 net/core/dev.c:7587
 napi_threaded_poll_loop+0x2e3/0x6c0 net/core/dev.c:7706
 napi_threaded_poll+0x1be/0x2b0 net/core/dev.c:7733
 kthread+0x711/0x8a0 kernel/kthread.c:463
 ret_from_fork+0x4bc/0x870 arch/x86/kernel/process.c:158
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
 </TASK>
rcu: rcu_preempt kthread timer wakeup didn't happen for 10501 jiffies! g15677 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x402
rcu: 	Possible timer handling issue on cpu=1 timer-softirq=5370
rcu: rcu_preempt kthread starved for 10502 jiffies! g15677 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x402 ->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:27496 pid:16    tgid:16    ppid:2      task_flags:0x208040 flags:0x00080000
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5360 [inline]
 __schedule+0x1798/0x4cc0 kernel/sched/core.c:6964
 __schedule_loop kernel/sched/core.c:7046 [inline]
 schedule+0x165/0x360 kernel/sched/core.c:7061
 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+0x711/0x8a0 kernel/kthread.c:463
 ret_from_fork+0x4bc/0x870 arch/x86/kernel/process.c:158
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
 </TASK>
sched: DL replenish lagged too much