rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 	Tasks blocked on level-0 rcu_node (CPUs 0-1): P10460/1:b..l
rcu: 	(detected by 1, t=10510 jiffies, g=38849, q=1384 ncpus=2)
task:syz.0.505       state:R  running task     stack:24376 pid:10460 tgid:10443 ppid:5624   task_flags:0x400040 flags:0x00080002
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5520 [inline]
 __schedule+0x17d4/0x5820 kernel/sched/core.c:7270
 preempt_schedule_irq+0x4b/0x90 kernel/sched/core.c:7592
 irqentry_exit_to_kernel_mode include/linux/irq-entry-common.h:539 [inline]
 irqentry_exit+0x14f/0x910 kernel/entry/common.c:167
 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:674
RIP: 0010:lock_release+0x20/0x3c0 kernel/locking/lockdep.c:5917
Code: 90 90 90 90 90 90 90 90 90 90 f3 0f 1e fa 55 41 57 41 56 41 55 41 54 53 48 83 ec 30 49 89 f5 49 89 fe 65 48 8b 05 48 d7 f0 11 <48> 89 44 24 28 0f 1f 44 00 00 65 8b 05 47 d7 f0 11 83 f8 08 0f 83
RSP: 0018:ffffc900068468b8 EFLAGS: 00000286
RAX: c47fa5b060f23800 RBX: ffffffff81b0e3ed RCX: 8000000000000001
RDX: 00000000105209fd RSI: ffffffff81b0e3ed RDI: ffffffff8ed5c6e0
RBP: 0000000000000000 R08: c800000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: ffffffff8ed5c6e0 R12: ffff888066de9f40
R13: ffffffff81b0e3ed R14: ffffffff8ed5c6e0 R15: 1ffff92000d08d3e
 rcu_lock_release include/linux/rcupdate.h:319 [inline]
 rcu_read_unlock include/linux/rcupdate.h:880 [inline]
 class_rcu_destructor include/linux/rcupdate.h:1216 [inline]
 is_module_text_address+0x18b/0x1e0 kernel/module/main.c:3936
 kernel_text_address+0x94/0xe0 kernel/extable.c:119
 __kernel_text_address+0xd/0x30 kernel/extable.c:79
 unwind_get_return_address+0x4d/0x90 arch/x86/kernel/unwind_orc.c:385
 arch_stack_walk+0xfb/0x150 arch/x86/kernel/stacktrace.c:26
 stack_trace_save+0xa9/0x100 kernel/stacktrace.c:122
 save_stack+0x122/0x230 mm/page_owner.c:183
 __reset_page_owner+0x71/0x1f0 mm/page_owner.c:338
 reset_page_owner include/linux/page_owner.h:26 [inline]
 __free_pages_prepare mm/page_alloc.c:1418 [inline]
 __free_frozen_pages+0xc93/0xd90 mm/page_alloc.c:2962
 __folio_put+0x4b3/0x590 mm/folio.c:105
 folio_put_refs include/linux/mm.h:2180 [inline]
 collapse_file mm/khugepaged.c:2649 [inline]
 collapse_scan_file+0x41d8/0x5180 mm/khugepaged.c:2778
 collapse_single_pmd+0x2a2/0x3c50 mm/khugepaged.c:2813
 madvise_collapse+0x2cf/0x790 mm/khugepaged.c:3237
 madvise_vma_behavior+0x115f/0x4170 mm/madvise.c:1364
 madvise_walk_vmas+0x576/0xb00 mm/madvise.c:1713
 madvise_do_behavior+0x385/0x540 mm/madvise.c:1908
 do_madvise+0x327/0x3a0 mm/madvise.c:2006
 __do_sys_madvise mm/madvise.c:2015 [inline]
 __se_sys_madvise mm/madvise.c:2013 [inline]
 __x64_sys_madvise+0xa6/0xc0 mm/madvise.c:2013
 do_syscall_x64 arch/x86/entry/syscall_64.c:61 [inline]
 do_syscall_64+0x166/0x520 arch/x86/entry/syscall_64.c:84
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f37a599e159
RSP: 002b:00007f37a682c028 EFLAGS: 00000246 ORIG_RAX: 000000000000001c
RAX: ffffffffffffffda RBX: 00007f37a5c26090 RCX: 00007f37a599e159
RDX: 0000000000000019 RSI: 000000000060005f RDI: 0000200000000000
RBP: 00007f37a5a35024 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f37a5c26128 R14: 00007f37a5c26090 R15: 00007f37a5d4fa48
 </TASK>
rcu: rcu_preempt kthread starved for 358 jiffies! g38849 f0x0 RCU_GP_WAIT_FQS(5) ->state=R ->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:27656 pid:17    tgid:17    ppid:2      task_flags:0x208040 flags:0x00080000
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5520 [inline]
 __schedule+0x17d4/0x5820 kernel/sched/core.c:7270
 __schedule_loop kernel/sched/core.c:7347 [inline]
 schedule+0x164/0x2b0 kernel/sched/core.c:7362
 schedule_timeout+0x152/0x2c0 kernel/time/sleep_timeout.c:99
 rcu_gp_fqs_loop+0x30c/0x11f0 kernel/rcu/tree.c:2122
 rcu_gp_kthread+0x9e/0x2b0 kernel/rcu/tree.c:2330
 kthread+0x38b/0x480 kernel/kthread.c:436
 ret_from_fork+0x514/0xb70 arch/x86/kernel/process.c:158
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
 </TASK>
rcu: Stack dump where RCU GP kthread last ran:
CPU: 1 UID: 0 PID: 8245 Comm: kworker/u8:23 Tainted: G             L      syzkaller #0 PREEMPT(full) 
Tainted: [L]=SOFTLOCKUP
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/24/2026
Workqueue: wg-kex-wg1 wg_packet_handshake_send_worker
RIP: 0010:cpumask_test_cpu include/linux/cpumask.h:650 [inline]
RIP: 0010:cpu_online include/linux/cpumask.h:1232 [inline]
RIP: 0010:trace_lock_acquire include/trace/events/lock.h:23 [inline]
RIP: 0010:lock_acquire+0x47/0x350 kernel/locking/lockdep.c:5871
Code: 24 04 41 89 f6 49 89 fc 65 48 8b 05 8b 09 f1 11 48 89 44 24 50 0f 1f 44 00 00 65 8b 05 8a 09 f1 11 83 f8 08 0f 83 9b 01 00 00 <89> c0 48 0f a3 05 b7 22 d7 0e 73 0d e8 68 34 09 00 84 c0 0f 84 e2
RSP: 0018:ffffc90000a171c8 EFLAGS: 00000297
RAX: 0000000000000001 RBX: 0000000000000000 RCX: 0000000000000002
RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffffffff8ed5c6e0
RBP: 1ffff92000142e68 R08: 0000000000000000 R09: 0000000000000000
R10: ffffc90000a17358 R11: ffffffff81b272d0 R12: ffffffff8ed5c6e0
R13: 0000000000000002 R14: 0000000000000000 R15: 0000000000000000
FS:  0000000000000000(0000) GS:ffff888124dde000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00002000001b6030 CR3: 0000000033e46000 CR4: 00000000003526f0
Call Trace:
 <IRQ>
 rcu_lock_acquire include/linux/rcupdate.h:309 [inline]
 rcu_read_lock include/linux/rcupdate.h:849 [inline]
 class_rcu_constructor include/linux/rcupdate.h:1216 [inline]
 unwind_next_frame+0xac/0x2550 arch/x86/kernel/unwind_orc.c:495
 arch_stack_walk+0x11b/0x150 arch/x86/kernel/stacktrace.c:25
 stack_trace_save+0xa9/0x100 kernel/stacktrace.c:122
 kasan_save_stack mm/kasan/common.c:57 [inline]
 kasan_save_track+0x3e/0x80 mm/kasan/common.c:78
 kasan_save_free_info+0x40/0x50 mm/kasan/generic.c:584
 poison_slab_object mm/kasan/common.c:253 [inline]
 __kasan_slab_free+0x5c/0x80 mm/kasan/common.c:285
 kasan_slab_free include/linux/kasan.h:235 [inline]
 slab_free_hook mm/slub.c:2748 [inline]
 slab_free mm/slub.c:6499 [inline]
 kmem_cache_free+0x182/0x650 mm/slub.c:6626
 skb_ext_reset include/linux/skbuff.h:5118 [inline]
 skb_scrub_packet+0x2c8/0x3d0 net/core/skbuff.c:6284
 ____dev_forward_skb include/linux/netdevice.h:4483 [inline]
 __dev_forward_skb2+0x28c/0x730 net/core/dev.c:2466
 veth_forward_skb drivers/net/veth.c:324 [inline]
 veth_xmit+0x493/0xe60 drivers/net/veth.c:380
 __netdev_start_xmit include/linux/netdevice.h:5429 [inline]
 netdev_start_xmit include/linux/netdevice.h:5438 [inline]
 xmit_one net/core/dev.c:3937 [inline]
 dev_hard_start_xmit+0x2cd/0x830 net/core/dev.c:3953
 __dev_queue_xmit+0x14c0/0x3820 net/core/dev.c:4926
 dev_queue_xmit include/linux/netdevice.h:3461 [inline]
 br_dev_queue_push_xmit+0x370/0x4b0 net/bridge/br_forward.c:53
 NF_HOOK+0x64e/0x6e0 include/linux/netfilter.h:325
 br_nf_post_routing+0xa53/0xee0 net/bridge/br_netfilter_hooks.c:964
 nf_hook_entry_hookfn include/linux/netfilter.h:165 [inline]
 nf_hook_slow+0xc5/0x220 net/netfilter/core.c:619
 nf_hook include/linux/netfilter.h:280 [inline]
 NF_HOOK+0x23e/0x3f0 include/linux/netfilter.h:323
 br_forward_finish+0xd3/0x130 net/bridge/br_forward.c:66
 br_nf_hook_thresh net/bridge/br_netfilter_hooks.c:1165 [inline]
 br_nf_forward_finish+0xa76/0xea0 net/bridge/br_netfilter_hooks.c:667
 NF_HOOK+0x64e/0x6e0 include/linux/netfilter.h:325
 br_nf_forward_ip+0x7eb/0xa30 net/bridge/br_netfilter_hooks.c:721
 nf_hook_entry_hookfn include/linux/netfilter.h:165 [inline]
 nf_hook_slow+0xc5/0x220 net/netfilter/core.c:619
 nf_hook include/linux/netfilter.h:280 [inline]
 NF_HOOK+0x23e/0x3f0 include/linux/netfilter.h:323
 __br_forward+0x397/0x540 net/bridge/br_forward.c:115
 deliver_clone net/bridge/br_forward.c:131 [inline]
 maybe_deliver net/bridge/br_forward.c:191 [inline]
 br_flood+0x3e6/0x8d0 net/bridge/br_forward.c:245
 br_handle_frame_finish+0x1119/0x1950 net/bridge/br_input.c:229
 br_nf_hook_thresh+0x3dd/0x4c0 net/bridge/br_netfilter_hooks.c:-1
 br_nf_pre_routing_finish_ipv6+0x90c/0xc40 net/bridge/br_netfilter_ipv6.c:-1
 NF_HOOK include/linux/netfilter.h:325 [inline]
 br_nf_pre_routing_ipv6+0x382/0x6f0 net/bridge/br_netfilter_ipv6.c:183
 nf_hook_entry_hookfn include/linux/netfilter.h:165 [inline]
 nf_hook_bridge_pre net/bridge/br_input.c:291 [inline]
 br_handle_frame+0x127f/0x1510 net/bridge/br_input.c:442
 __netif_receive_skb_core+0x989/0x30c0 net/core/dev.c:6151
 __netif_receive_skb_one_core net/core/dev.c:6262 [inline]
 __netif_receive_skb net/core/dev.c:6377 [inline]
 process_backlog+0x727/0x18b0 net/core/dev.c:6728
 __napi_poll+0xaa/0x330 net/core/dev.c:7787
 napi_poll net/core/dev.c:7850 [inline]
 net_rx_action+0x61d/0xf50 net/core/dev.c:8007
 handle_softirqs+0x226/0x860 kernel/softirq.c:645
 do_softirq+0x77/0xd0 kernel/softirq.c:546
 </IRQ>
 <TASK>
 __local_bh_enable_ip+0x100/0x140 kernel/softirq.c:473
 blake2s_compress+0xfa/0x1c00 lib/crypto/x86/blake2s.h:42
 blake2s_update+0x140/0x450 lib/crypto/blake2s.c:119
 hmac+0x2d1/0x3b0 drivers/net/wireguard/noise.c:332
 kdf drivers/net/wireguard/noise.c:360 [inline]
 message_ephemeral+0x233/0x310 drivers/net/wireguard/noise.c:493
 wg_noise_handshake_create_initiation+0x24f/0x810 drivers/net/wireguard/noise.c:545
 wg_packet_send_handshake_initiation drivers/net/wireguard/send.c:34 [inline]
 wg_packet_handshake_send_worker+0x18c/0x370 drivers/net/wireguard/send.c:51
 process_one_work kernel/workqueue.c:3387 [inline]
 process_scheduled_works+0xc3d/0x1630 kernel/workqueue.c:3470
 worker_thread+0xa47/0xfb0 kernel/workqueue.c:3551
 kthread+0x38b/0x480 kernel/kthread.c:436
 ret_from_fork+0x514/0xb70 arch/x86/kernel/process.c:158
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
 </TASK>