rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P32157/1:b..l P24039/1:b..l
rcu: (detected by 1, t=10503 jiffies, g=142073, q=991 ncpus=2)
task:syz-executor state:R running task stack:21640 pid:24039 tgid:24039 ppid:1 task_flags:0x40054c flags:0x00004004
Call Trace:
<TASK>
context_switch kernel/sched/core.c:5397 [inline]
__schedule+0x16f5/0x4d00 kernel/sched/core.c:6786
preempt_schedule_common+0x83/0xd0 kernel/sched/core.c:6966
preempt_schedule+0xae/0xc0 kernel/sched/core.c:6990
preempt_schedule_thunk+0x16/0x30 arch/x86/entry/thunk.S:12
__raw_spin_unlock include/linux/spinlock_api_smp.h:143 [inline]
_raw_spin_unlock+0x3f/0x50 kernel/locking/spinlock.c:186
spin_unlock include/linux/spinlock.h:391 [inline]
zap_pte_range mm/memory.c:1765 [inline]
zap_pmd_range mm/memory.c:1827 [inline]
zap_pud_range mm/memory.c:1856 [inline]
zap_p4d_range mm/memory.c:1877 [inline]
unmap_page_range+0x3842/0x41c0 mm/memory.c:1898
unmap_single_vma mm/memory.c:1941 [inline]
unmap_vmas+0x399/0x580 mm/memory.c:1985
exit_mmap+0x248/0xb50 mm/mmap.c:1284
__mmput+0x118/0x420 kernel/fork.c:1121
exit_mm+0x1da/0x2c0 kernel/exit.c:581
do_exit+0x648/0x22e0 kernel/exit.c:952
do_group_exit+0x21c/0x2d0 kernel/exit.c:1105
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:111
exit_to_user_mode_prepare include/linux/entry-common.h:330 [inline]
syscall_exit_to_user_mode_work include/linux/entry-common.h:414 [inline]
syscall_exit_to_user_mode include/linux/entry-common.h:449 [inline]
do_syscall_64+0x2bd/0x3b0 arch/x86/entry/syscall_64.c:100
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f96811c1265
RSP: 002b:00007ffe90787dd0 EFLAGS: 00000293 ORIG_RAX: 00000000000000e6
RAX: 0000000000000000 RBX: 00000000000005cb RCX: 00007f96811c1265
RDX: 00007ffe90787e10 RSI: 0000000000000000 RDI: 0000000000000000
RBP: 00007ffe90787e7c R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000293 R12: 000000000000021a
R13: 0000000000000064 R14: 00000000000c9bb0 R15: 00007ffe90787ed0
</TASK>
task:syz.1.8871 state:R running task stack:26056 pid:32157 tgid:32156 ppid:23253 task_flags:0x40054c flags:0x00004002
Call Trace:
<TASK>
context_switch kernel/sched/core.c:5397 [inline]
__schedule+0x16f5/0x4d00 kernel/sched/core.c:6786
preempt_schedule_irq+0xb5/0x150 kernel/sched/core.c:7109
irqentry_exit+0x6f/0x90 kernel/entry/common.c:307
asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702
RIP: 0010:__nr_to_section include/linux/mmzone.h:1937 [inline]
RIP: 0010:__pfn_to_section include/linux/mmzone.h:2075 [inline]
RIP: 0010:lookup_page_ext mm/page_ext.c:251 [inline]
RIP: 0010:page_ext_lookup+0x90/0x180 mm/page_ext.c:520
Code: 74 0c 48 c7 c7 40 f0 b0 99 e8 7c f2 f4 ff 48 8b 05 45 a8 83 17 48 85 c0 74 36 4e 8d 34 f0 4c 89 f0 48 c1 e8 03 42 80 3c 28 00 <74> 08 4c 89 f7 e8 56 f2 f4 ff 4d 8b 36 4d 85 f6 74 1b 48 c1 eb 0f
RSP: 0018:ffffc9000eef7108 EFLAGS: 00000246
RAX: 1ffff11047ffde80 RBX: 0000000000057500 RCX: ffff888033c70000
RDX: 0000000000000000 RSI: 0000000000001000 RDI: 0000000000000000
RBP: 0000000000000001 R08: 0000000000000000 R09: ffffffff822d525a
R10: dffffc0000000000 R11: ffffed100b19d9f0 R12: 0000000000057500
R13: dffffc0000000000 R14: ffff88823ffef400 R15: 0000000000001000
page_ext_iter_begin include/linux/page_ext.h:132 [inline]
__page_table_check_zero+0x18f/0x530 mm/page_table_check.c:139
page_table_check_free include/linux/page_table_check.h:43 [inline]
free_pages_prepare mm/page_alloc.c:1249 [inline]
__free_frozen_pages+0xc84/0xe70 mm/page_alloc.c:2706
__slab_free+0x326/0x400 mm/slub.c:4554
qlink_free mm/kasan/quarantine.c:163 [inline]
qlist_free_all+0x97/0x140 mm/kasan/quarantine.c:179
kasan_quarantine_reduce+0x148/0x160 mm/kasan/quarantine.c:286
__kasan_slab_alloc+0x22/0x80 mm/kasan/common.c:329
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+0x1bb/0x3c0 mm/slub.c:4249
kmalloc_reserve+0xbd/0x290 net/core/skbuff.c:579
__alloc_skb+0x142/0x2d0 net/core/skbuff.c:670
alloc_skb include/linux/skbuff.h:1336 [inline]
alloc_uevent_skb+0x7d/0x230 lib/kobject_uevent.c:289
uevent_net_broadcast_tagged lib/kobject_uevent.c:352 [inline]
kobject_uevent_net_broadcast+0x184/0x560 lib/kobject_uevent.c:413
kobject_uevent_env+0x55b/0x8c0 lib/kobject_uevent.c:608
__kobject_del+0xd2/0x300 lib/kobject.c:601
kobject_cleanup lib/kobject.c:680 [inline]
kobject_release lib/kobject.c:720 [inline]
kref_put include/linux/kref.h:65 [inline]
kobject_put+0x243/0x480 lib/kobject.c:737
net_rx_queue_update_kobjects+0x66f/0x720 net/core/net-sysfs.c:1317
remove_queue_kobjects net/core/net-sysfs.c:2148 [inline]
netdev_unregister_kobject+0x113/0x450 net/core/net-sysfs.c:2304
unregister_netdevice_many_notify+0x1d52/0x2320 net/core/dev.c:12112
unregister_netdevice_many net/core/dev.c:12140 [inline]
unregister_netdevice_queue+0x33c/0x380 net/core/dev.c:11984
unregister_netdevice include/linux/netdevice.h:3379 [inline]
ppp_release+0xed/0x1f0 drivers/net/ppp/ppp_generic.c:422
__fput+0x44c/0xa70 fs/file_table.c:465
task_work_run+0x1d1/0x260 kernel/task_work.c:227
exit_task_work include/linux/task_work.h:40 [inline]
do_exit+0x6b5/0x22e0 kernel/exit.c:964
do_group_exit+0x21c/0x2d0 kernel/exit.c:1105
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:111
exit_to_user_mode_prepare include/linux/entry-common.h:330 [inline]
syscall_exit_to_user_mode_work include/linux/entry-common.h:414 [inline]
syscall_exit_to_user_mode include/linux/entry-common.h:449 [inline]
do_syscall_64+0x2bd/0x3b0 arch/x86/entry/syscall_64.c:100
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f6f3c58e9a9
RSP: 002b:00007f6f3d489fd8 EFLAGS: 00000246 ORIG_RAX: 0000000000000029
RAX: 000000000000000a RBX: 0000000000000007 RCX: 00007f6f3c58e9a9
RDX: 0000000000000000 RSI: 0000000000000002 RDI: 0000000000000003
RBP: 00007f6f3c610d69 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 0000000000000000 R14: 00007f6f3c7b5fa0 R15: 00007ffca8177aa8
</TASK>
rcu: rcu_preempt kthread starved for 1722 jiffies! g142073 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x0 ->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:R running task stack:26792 pid:16 tgid:16 ppid:2 task_flags:0x208040 flags:0x00004000
Call Trace:
<TASK>
context_switch kernel/sched/core.c:5397 [inline]
__schedule+0x16f5/0x4d00 kernel/sched/core.c:6786
__schedule_loop kernel/sched/core.c:6864 [inline]
schedule+0x165/0x360 kernel/sched/core.c:6879
schedule_timeout+0x12b/0x270 kernel/time/sleep_timeout.c:99
rcu_gp_fqs_loop+0x301/0x1540 kernel/rcu/tree.c:2054
rcu_gp_kthread+0x99/0x390 kernel/rcu/tree.c:2256
kthread+0x70e/0x8a0 kernel/kthread.c:464
ret_from_fork+0x3fc/0x770 arch/x86/kernel/process.c:148
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
</TASK>
rcu: Stack dump where RCU GP kthread last ran:
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 17709 Comm: kworker/u8:20 Not tainted 6.16.0-rc6-syzkaller-00128-g81e0db8e8398 #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025
Workqueue: wg-kex-wg0 wg_packet_handshake_send_worker
RIP: 0010:rcu_read_lock_held+0x0/0x50 kernel/rcu/update.c:346
Code: 05 81 d9 fb 0d c3 cc cc cc cc cc 66 66 66 66 66 66 2e 0f 1f 84 00 00 00 00 00 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 <f3> 0f 1e fa 53 e8 86 91 c7 09 85 c0 74 26 31 db e8 fb 2d 01 00 84
RSP: 0018:ffffc90000007520 EFLAGS: 00000202
RAX: ffffffff8a4fef97 RBX: ffffffff8a4feebe RCX: 0000000000000100
RDX: ffff888029f98000 RSI: 0000000000000001 RDI: 0000000000000000
RBP: 000000000000004b R08: 0000000000000000 R09: ffffffff8a4feebe
R10: ffff888152342610 R11: ffffed102a4684c6 R12: ffff88801fae3000
R13: dffffc0000000000 R14: 0000000000000001 R15: dffffc0000000000
FS: 0000000000000000(0000) GS:ffff888125c23000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000555562999808 CR3: 00000000780f8000 CR4: 00000000003526f0
Call Trace:
<IRQ>
net_generic+0x101/0x240 include/net/netns/generic.h:46
brnf_get_logical_dev+0x30/0x270 net/bridge/br_netfilter_hooks.c:435
setup_pre_routing+0x1b2/0x470 net/bridge/br_netfilter_hooks.c:460
br_nf_pre_routing_ipv6+0x160/0x6b0 net/bridge/br_netfilter_ipv6.c:175
nf_hook_entry_hookfn include/linux/netfilter.h:157 [inline]
nf_hook_bridge_pre net/bridge/br_input.c:283 [inline]
br_handle_frame+0x982/0x14c0 net/bridge/br_input.c:434
__netif_receive_skb_core+0x10de/0x4180 net/core/dev.c:5863
__netif_receive_skb_one_core net/core/dev.c:5975 [inline]
__netif_receive_skb+0x72/0x380 net/core/dev.c:6090
process_backlog+0x60e/0x14f0 net/core/dev.c:6442
__napi_poll+0xc7/0x480 net/core/dev.c:7414
napi_poll net/core/dev.c:7478 [inline]
net_rx_action+0x707/0xe30 net/core/dev.c:7605
handle_softirqs+0x286/0x870 kernel/softirq.c:579
do_softirq+0xec/0x180 kernel/softirq.c:480
</IRQ>
<TASK>
__local_bh_enable_ip+0x17d/0x1c0 kernel/softirq.c:407
wg_packet_send_handshake_initiation drivers/net/wireguard/send.c:36 [inline]
wg_packet_handshake_send_worker+0x184/0x320 drivers/net/wireguard/send.c:51
process_one_work kernel/workqueue.c:3238 [inline]
process_scheduled_works+0xae1/0x17b0 kernel/workqueue.c:3321
worker_thread+0x8a0/0xda0 kernel/workqueue.c:3402
kthread+0x70e/0x8a0 kernel/kthread.c:464
ret_from_fork+0x3fc/0x770 arch/x86/kernel/process.c:148
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
</TASK>
net_ratelimit: 4388 callbacks suppressed
bridge0: received packet on veth0_to_bridge with own address as source address (addr:aa:aa:aa:aa:aa:0c, vlan:0)
bridge0: received packet on bridge_slave_0 with own address as source address (addr:aa:aa:aa:aa:aa:1b, vlan:0)
bridge0: received packet on bridge_slave_0 with own address as source address (addr:aa:aa:aa:aa:aa:0c, vlan:0)
bridge0: received packet on veth0_to_bridge with own address as source address (addr:aa:aa:aa:aa:aa:0c, vlan:0)
bridge0: received packet on bridge_slave_0 with own address as source address (addr:aa:aa:aa:aa:aa:1b, vlan:0)
bridge0: received packet on bridge_slave_0 with own address as source address (addr:aa:aa:aa:aa:aa:0c, vlan:0)
bridge0: received packet on veth0_to_bridge with own address as source address (addr:aa:aa:aa:aa:aa:0c, vlan:0)
bridge0: received packet on bridge_slave_0 with own address as source address (addr:aa:aa:aa:aa:aa:1b, vlan:0)
bridge0: received packet on bridge_slave_0 with own address as source address (addr:aa:aa:aa:aa:aa:0c, vlan:0)
bridge0: received packet on veth0_to_bridge with own address as source address (addr:aa:aa:aa:aa:aa:0c, vlan:0)