rcu: INFO: rcu_preempt self-detected stall on CPU
rcu: 1-....: (10260 ticks this GP) idle=af04/1/0x4000000000000000 softirq=78484/78484 fqs=3411
rcu: hardirqs softirqs csw/system
rcu: number: 1188032 0 0
rcu: cputime: 11413 27453 36 ==> 38900(ms)
rcu: (t=10503 jiffies g=101313 q=1283 ncpus=2)
rcu: rcu_preempt kthread timer wakeup didn't happen for 1204 jiffies! g101313 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x402
rcu: Possible timer handling issue on cpu=0 timer-softirq=63636
rcu: rcu_preempt kthread starved for 1207 jiffies! g101313 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x402 ->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:I stack:26856 pid:17 ppid:2 flags:0x00004000
Call Trace:
context_switch kernel/sched/core.c:5382 [inline]
__schedule+0x15ae/0x4660 kernel/sched/core.c:6701
schedule+0xbd/0x170 kernel/sched/core.c:6775
schedule_timeout+0x188/0x2d0 kernel/time/timer.c:2168
rcu_gp_fqs_loop+0x30d/0x1590 kernel/rcu/tree.c:1667
rcu_gp_kthread+0x9d/0x3b0 kernel/rcu/tree.c:1866
kthread+0x2fa/0x390 kernel/kthread.c:388
ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:152
ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:293
rcu: Stack dump where RCU GP kthread last ran:
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 PID: 8394 Comm: kworker/u4:23 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/24/2026
Workqueue: wg-kex-wg0 wg_packet_handshake_send_worker
RIP: 0010:queued_write_lock_slowpath+0x12c/0x29f kernel/locking/qrwlock.c:85
Code: f0 41 81 0e 00 01 00 00 42 0f b6 04 23 84 c0 74 37 44 89 f1 80 e1 07 80 c1 03 38 c1 7c 2a 4c 89 f7 e8 f8 78 46 f7 eb 20 f3 90 <42> 0f b6 04 23 84 c0 74 15 44 89 f1 80 e1 07 80 c1 03 38 c1 7c 08
RSP: 0018:ffffc9001001f3a0 EFLAGS: 00000206
RAX: 00000000000001ff RBX: 1ffff11004b2b705 RCX: ffffffff8a997702
RDX: 0000000000000001 RSI: 0000000000000004 RDI: ffff88802595b828
RBP: ffffc9001001f430 R08: ffff88802595b82b R09: 1ffff11004b2b705
R10: dffffc0000000000 R11: ffffed1004b2b706 R12: dffffc0000000000
R13: 1ffff92002003e74 R14: ffff88802595b828 R15: ffffc9001001f3d0
FS: 0000000000000000(0000) GS:ffff8880b8e00000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fff225a8080 CR3: 000000000cf32000 CR4: 00000000003506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000600
Call Trace:
queued_write_lock include/asm-generic/qrwlock.h:101 [inline]
do_raw_write_lock+0x1ea/0x260 kernel/locking/spinlock_debug.c:210
__neigh_event_send+0x39/0x1480 net/core/neighbour.c:1182
neigh_event_send_probe include/net/neighbour.h:467 [inline]
neigh_event_send include/net/neighbour.h:473 [inline]
neigh_resolve_output+0x1a4/0x710 net/core/neighbour.c:1552
neigh_output include/net/neighbour.h:547 [inline]
ip6_finish_output2+0xf7a/0x1690 net/ipv6/ip6_output.c:143
ip6tunnel_xmit include/net/ip6_tunnel.h:161 [inline]
udp_tunnel6_xmit_skb+0x516/0x930 net/ipv6/ip6_udp_tunnel.c:110
send6+0x608/0x950 drivers/net/wireguard/socket.c:152
wg_socket_send_skb_to_peer+0x111/0x1c0 drivers/net/wireguard/socket.c:178
wg_packet_send_handshake_initiation drivers/net/wireguard/send.c:40 [inline]
wg_packet_handshake_send_worker+0x207/0x360 drivers/net/wireguard/send.c:51
process_one_work kernel/workqueue.c:2657 [inline]
process_scheduled_works+0xa60/0x1600 kernel/workqueue.c:2734
worker_thread+0xa5e/0xfe0 kernel/workqueue.c:2815
kthread+0x2fa/0x390 kernel/kthread.c:388
ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:152
ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:293
CPU: 1 PID: 20554 Comm: syz.1.4097 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/24/2026
RIP: 0010:rcu_read_unlock_special+0x83/0x4d0 kernel/rcu/tree_plugin.h:763
Code: eb 03 48 b8 f1 f1 f1 f1 f8 f2 f2 f2 4a 89 04 2b 42 c7 44 2b 08 f8 f3 f3 f3 65 44 8b 35 5e b3 91 7e 41 f7 c6 00 00 f0 00 74 40 <48> c7 44 24 20 0e 36 e0 45 4a c7 04 2b 00 00 00 00 42 c7 44 2b 08
RSP: 0018:ffffc900001f04c0 EFLAGS: 00000206
RAX: 62b73c818e1ef900 RBX: 1ffff9200003e09c RCX: 62b73c818e1ef900
RDX: dffffc0000000000 RSI: ffffffff8acacbe0 RDI: ffffffff8b1d3360
RBP: ffffc900001f0588 R08: ffffffff911ef5c7 R09: 1ffffffff223deb8
R10: dffffc0000000000 R11: fffffbfff223deb9 R12: ffffffff8d137000
R13: dffffc0000000000 R14: ffff8880b8f3d190 R15: 1ffff110171e7a32
FS: 00007f02bb6716c0(0000) GS:ffff8880b8f00000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000100000000 CR3: 0000000028df5000 CR4: 00000000003506e0
DR0: 0000000000000000 DR1: 0000200000000300 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000600
Call Trace:
__rcu_read_unlock+0x7c/0xd0 kernel/rcu/tree_plugin.h:426
rcu_read_unlock include/linux/rcupdate.h:818 [inline]
is_bpf_text_address+0x27e/0x2a0 kernel/bpf/core.c:744
kernel_text_address+0xa0/0xd0 kernel/extable.c:125
__kernel_text_address+0xd/0x30 kernel/extable.c:79
unwind_get_return_address+0x5d/0xc0 arch/x86/kernel/unwind_orc.c:369
arch_stack_walk+0x11d/0x190 arch/x86/kernel/stacktrace.c:26
stack_trace_save+0xaa/0x100 kernel/stacktrace.c:122
kasan_save_stack mm/kasan/common.c:46 [inline]
kasan_set_track+0x4e/0x70 mm/kasan/common.c:53
kasan_save_free_info+0x28/0x40 mm/kasan/generic.c:522
____kasan_slab_free+0x126/0x1f0 mm/kasan/common.c:237
kasan_slab_free include/linux/kasan.h:164 [inline]
slab_free_hook mm/slub.c:1811 [inline]
slab_free_freelist_hook+0x130/0x1a0 mm/slub.c:1837
slab_free mm/slub.c:3830 [inline]
kmem_cache_free+0xf8/0x290 mm/slub.c:3852
__skb_queue_purge_reason include/linux/skbuff.h:3245 [inline]
__skb_queue_purge include/linux/skbuff.h:3250 [inline]
neigh_invalidate+0x39e/0x460 net/core/neighbour.c:1067
neigh_timer_handler+0x911/0xff0 net/core/neighbour.c:1151
call_timer_fn+0x189/0x540 kernel/time/timer.c:1701
expire_timers kernel/time/timer.c:1752 [inline]
__run_timers+0x570/0x810 kernel/time/timer.c:2023
run_timer_softirq+0x67/0xf0 kernel/time/timer.c:2036
handle_softirqs+0x27d/0x820 kernel/softirq.c:578
__do_softirq kernel/softirq.c:612 [inline]
invoke_softirq kernel/softirq.c:452 [inline]
__irq_exit_rcu+0xd3/0x190 kernel/softirq.c:661
irq_exit_rcu+0x9/0x20 kernel/softirq.c:673
instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1088 [inline]
sysvec_apic_timer_interrupt+0xa4/0xc0 arch/x86/kernel/apic/apic.c:1088
asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:687
RIP: 0010:bytes_is_nonzero mm/kasan/generic.c:85 [inline]
RIP: 0010:memory_is_nonzero mm/kasan/generic.c:102 [inline]
RIP: 0010:memory_is_poisoned_n mm/kasan/generic.c:127 [inline]
RIP: 0010:memory_is_poisoned mm/kasan/generic.c:159 [inline]
RIP: 0010:check_region_inline mm/kasan/generic.c:178 [inline]
RIP: 0010:kasan_check_range+0x89/0x290 mm/kasan/generic.c:187
Code: 00 fc ff df 4d 8d 34 19 4d 89 f4 4d 29 dc 49 83 fc 10 7f 29 4d 85 e4 0f 84 3d 01 00 00 4c 89 cb 48 f7 d3 4c 01 fb 41 80 3b 00 <0f> 85 8d 01 00 00 49 ff c3 48 ff c3 75 ee e9 1d 01 00 00 44 89 dd
RSP: 0018:ffffc90003377988 EFLAGS: 00000246
RAX: 0000000000000001 RBX: ffffffffffffffff RCX: ffffffff8a97a17e
RDX: 0000000000000001 RSI: 0000000000000010 RDI: ffffc90003377b70
RBP: 0000000000000000 R08: ffffc90003377b7f R09: 1ffff9200066ef6f
R10: dffffc0000000000 R11: fffff5200066ef6f R12: 0000000000000002
R13: ffff88805a149028 R14: fffff5200066ef70 R15: 1ffff9200066ef6e
__asan_memset+0x22/0x40 mm/kasan/shadow.c:84
__schedule+0xce/0x4660 kernel/sched/core.c:6584
preempt_schedule_common+0x82/0xc0 kernel/sched/core.c:6868
preempt_schedule+0xc0/0xd0 kernel/sched/core.c:6892
preempt_schedule_thunk+0x1a/0x30 arch/x86/entry/thunk_64.S:45
rcu_read_unlock_sched include/linux/rcupdate.h:901 [inline]
fd_install+0x397/0x4e0 fs/file.c:611
__do_sys_perf_event_open kernel/events/core.c:12978 [inline]
__se_sys_perf_event_open+0x19fe/0x1c60 kernel/events/core.c:12609
do_syscall_x64 arch/x86/entry/common.c:46 [inline]
do_syscall_64+0x55/0xb0 arch/x86/entry/common.c:76
entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7f02ba79e159
Code: ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 e8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007f02bb671028 EFLAGS: 00000246 ORIG_RAX: 000000000000012a
RAX: ffffffffffffffda RBX: 00007f02baa25fa0 RCX: 00007f02ba79e159
RDX: ffffffffffffffff RSI: 0000000000000000 RDI: 0000200000000480
RBP: 00007f02ba835024 R08: 0000000000000000 R09: 0000000000000000
R10: ffffffffffffffff R11: 0000000000000246 R12: 0000000000000000
R13: 00007f02baa26038 R14: 00007f02baa25fa0 R15: 00007ffed918b508