rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P7535/1:b..l P7529/1:b..l
rcu: (detected by 0, t=10503 jiffies, g=33353, q=722543 ncpus=2)
task:syz.2.420 state:R running task stack:25688 pid:7529 tgid:7524 ppid:5628 task_flags:0x40044c flags:0x00080002
Call Trace:
context_switch kernel/sched/core.c:5526 [inline]
__schedule+0x17db/0x58f0 kernel/sched/core.c:7276
preempt_schedule_common+0x7f/0xd0 kernel/sched/core.c:7455
preempt_schedule_thunk+0x16/0x40 arch/x86/entry/thunk.S:12
__raw_spin_unlock include/linux/spinlock_api_smp.h:201 [inline]
_raw_spin_unlock+0x41/0x50 kernel/locking/spinlock.c:213
spin_unlock include/linux/spinlock.h:401 [inline]
zap_pte_range mm/memory.c:2095 [inline]
zap_pmd_range mm/memory.c:2151 [inline]
zap_pud_range mm/memory.c:2179 [inline]
zap_p4d_range mm/memory.c:2200 [inline]
__zap_vma_range+0x40e1/0x4f80 mm/memory.c:2240
unmap_vmas+0x390/0x550 mm/memory.c:2309
exit_mmap+0x293/0x9f0 mm/mmap.c:1315
__mmput+0x118/0x420 kernel/fork.c:1193
exit_mm+0x221/0x2d0 kernel/exit.c:617
do_exit+0x6cd/0x2360 kernel/exit.c:999
do_group_exit+0x22d/0x2f0 kernel/exit.c:1154
get_signal+0x121b/0x12c0 kernel/signal.c:3051
arch_do_signal_or_restart+0xbb/0x860 arch/x86/kernel/signal.c:337
__exit_to_user_mode_loop kernel/entry/common.c:66 [inline]
exit_to_user_mode_loop+0x10e/0x770 kernel/entry/common.c:101
__exit_to_user_mode_prepare include/linux/irq-entry-common.h:207 [inline]
syscall_exit_to_user_mode_prepare include/linux/irq-entry-common.h:230 [inline]
syscall_exit_to_user_mode include/linux/entry-common.h:336 [inline]
do_syscall_64+0x328/0x520 arch/x86/entry/syscall_64.c:89
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fc26959e159
RSP: 002b:00007fc2677b4028 EFLAGS: 00000246 ORIG_RAX: 000000000000001c
RAX: fffffffffffffff4 RBX: 00007fc269826180 RCX: 00007fc26959e159
RDX: 0000000000000003 RSI: 7fffffffffffffff RDI: 0000200000000000
RBP: 00007fc26963503b R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007fc269826218 R14: 00007fc269826180 R15: 00007fc26994fa48
task:syz.1.422 state:R running task stack:25608 pid:7535 tgid:7535 ppid:5625 task_flags:0x40044c flags:0x00080003
Call Trace:
context_switch kernel/sched/core.c:5526 [inline]
__schedule+0x17db/0x58f0 kernel/sched/core.c:7276
preempt_schedule_irq+0x4b/0x90 kernel/sched/core.c:7598
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:trace_lock_acquire include/trace/events/lock.h:23 [inline]
RIP: 0010:lock_acquire+0x51/0x350 kernel/locking/lockdep.c:5905
Code: 8b 05 3b b7 f1 11 48 89 44 24 50 0f 1f 44 00 00 65 8b 05 3a b7 f1 11 83 f8 08 0f 83 9b 01 00 00 89 c0 48 0f a3 05 67 02 d7 0e <73> 0d e8 f8 34 09 00 84 c0 0f 84 e2 01 00 00 83 3d 59 33 d7 0e 00
RSP: 0018:ffffc9000328f4b8 EFLAGS: 00000293
RAX: 0000000000000000 RBX: 0000000000000000 RCX: 0000000000000002
RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffffffff8ed5c8a0
RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000010 R11: ffffffff81b285d0 R12: ffffffff8ed5c8a0
R13: 0000000000000002 R14: 0000000000000000 R15: 0000000000000000
rcu_lock_acquire include/linux/rcupdate.h:309 [inline]
rcu_read_lock include/linux/rcupdate.h:849 [inline]
__update_page_owner_free_handle+0x4b/0x4a0 mm/page_owner.c:301
__reset_page_owner+0x85/0x1f0 mm/page_owner.c:339
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
__slab_free+0x274/0x2c0 mm/slub.c:5815
qlink_free mm/kasan/quarantine.c:163 [inline]
qlist_free_all+0x99/0x100 mm/kasan/quarantine.c:179
kasan_quarantine_reduce+0x148/0x160 mm/kasan/quarantine.c:286
__kasan_slab_alloc+0x22/0x80 mm/kasan/common.c:350
kasan_slab_alloc include/linux/kasan.h:253 [inline]
slab_post_alloc_hook mm/slub.c:4683 [inline]
slab_alloc_node mm/slub.c:4996 [inline]
__kmalloc_cache_noprof+0x29f/0x600 mm/slub.c:5559
_kmalloc_noprof include/linux/slab.h:991 [inline]
_kzalloc_noprof include/linux/slab.h:1312 [inline]
kobject_uevent_env+0x289/0x9e0 lib/kobject_uevent.c:543
device_remove drivers/base/dd.c:616 [inline]
__device_release_driver drivers/base/dd.c:1349 [inline]
device_release_driver_internal+0x48b/0x880 drivers/base/dd.c:1372
driver_detach+0x1f3/0x2d0 drivers/base/dd.c:1435
bus_remove_driver+0x226/0x320 drivers/base/bus.c:832
usb_gadget_unregister_driver+0x4e/0x70 drivers/usb/gadget/udc/core.c:1784
raw_release+0xd7/0x260 drivers/usb/gadget/legacy/raw_gadget.c:463
__fput+0x418/0xa50 fs/file_table.c:512
task_work_run+0x1d9/0x270 kernel/task_work.c:233
exit_task_work include/linux/task_work.h:40 [inline]
do_exit+0x73a/0x2360 kernel/exit.c:1011
do_group_exit+0x22d/0x2f0 kernel/exit.c:1154
get_signal+0x121b/0x12c0 kernel/signal.c:3051
arch_do_signal_or_restart+0xbb/0x860 arch/x86/kernel/signal.c:337
__exit_to_user_mode_loop kernel/entry/common.c:66 [inline]
exit_to_user_mode_loop+0x10e/0x770 kernel/entry/common.c:101
__exit_to_user_mode_prepare include/linux/irq-entry-common.h:207 [inline]
syscall_exit_to_user_mode_prepare include/linux/irq-entry-common.h:230 [inline]
syscall_exit_to_user_mode include/linux/entry-common.h:336 [inline]
do_syscall_64+0x328/0x520 arch/x86/entry/syscall_64.c:89
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fbbd679e159
RSP: 002b:00007fbbd6b4fba8 EFLAGS: 00000246 ORIG_RAX: 00000000000000ca
RAX: ffffffffffffff92 RBX: 000000000003d692 RCX: 00007fbbd679e159
RDX: 0000000000000000 RSI: 0000000000000080 RDI: 00007fbbd6a25fac
RBP: 0000000000000bea R08: 3fffffffffffffff R09: 0000000000000000
R10: 00007fbbd6b4fcb0 R11: 0000000000000246 R12: 00007fbbd6b4fcd0
R13: 00007fbbd6a25fac R14: 000000000003e27c R15: 00007fbbd6b4fcb0
rcu: rcu_preempt kthread starved for 1611 jiffies! g33353 f0x2 RCU_GP_WAIT_FQS(5) ->state=R ->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:27496 pid:17 tgid:17 ppid:2 task_flags:0x208040 flags:0x00080000
Call Trace:
context_switch kernel/sched/core.c:5526 [inline]
__schedule+0x17db/0x58f0 kernel/sched/core.c:7276
__schedule_loop kernel/sched/core.c:7353 [inline]
schedule+0x164/0x2b0 kernel/sched/core.c:7368
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
rcu: Stack dump where RCU GP kthread last ran:
CPU: 0 UID: 0 PID: 4364 Comm: kworker/0:2 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-wg0 wg_packet_handshake_receive_worker
RIP: 0010:arch_static_branch_jump kernel/sched/clock.c:303 [inline]
RIP: 0010:local_clock_noinstr+0x4/0xe0 kernel/sched/clock.c:306
Code: 48 c7 c7 20 09 0b 8c e8 fa 65 42 f5 cc cc cc cc cc cc cc cc cc cc 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 0f 1f 40 d6 <53> 66 90 e8 b4 d4 ff ff 48 03 05 0d 38 95 04 5b c3 cc cc cc cc cc
RSP: 0018:ffffc90000006870 EFLAGS: 00000286
RAX: ffffffff8241e40a RBX: 00000000000d2820 RCX: ffff888035595dc0
RDX: 8000000000000300 RSI: 0000000000000100 RDI: ffffea0005f3d480
RBP: ffffc90000006930 R08: ffffffff907a2b7f R09: 0000000000000000
R10: ffffed102f9ea400 R11: fffffbfff20f4570 R12: ffff88817cf52000
R13: dffffc0000000000 R14: ffffea0005f3d480 R15: 0000000000000001
FS: 0000000000000000(0000) GS:ffff888124cd2000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000020000034f030 CR3: 000000000eb48000 CR4: 00000000003526f0
Call Trace:
local_clock+0x11/0x30 kernel/sched/clock.c:321
__set_page_owner+0x7f/0x4c0 mm/page_owner.c:356
set_page_owner include/linux/page_owner.h:33 [inline]
post_alloc_hook+0x1f9/0x250 mm/page_alloc.c:1871
prep_new_page mm/page_alloc.c:1879 [inline]
get_page_from_freelist+0x2209/0x2280 mm/page_alloc.c:3943
__alloc_frozen_pages_noprof+0x217/0x5a0 mm/page_alloc.c:5436
alloc_slab_page mm/slub.c:3347 [inline]
allocate_slab+0x7d/0x620 mm/slub.c:3462
new_slab mm/slub.c:3513 [inline]
refill_objects+0x2d5/0x350 mm/slub.c:7410
refill_sheaf mm/slub.c:2885 [inline]
__pcs_replace_empty_main+0x2c8/0x6c0 mm/slub.c:4774
alloc_from_pcs mm/slub.c:4850 [inline]
slab_alloc_node mm/slub.c:4984 [inline]
kmem_cache_alloc_noprof+0x399/0x600 mm/slub.c:5010
skb_clone+0x212/0x3a0 net/core/skbuff.c:2119
netem_enqueue+0xecb/0x32b0 net/sched/sch_netem.c:507
dev_qdisc_enqueue+0x4e/0x260 net/core/dev.c:4227
__dev_xmit_skb net/core/dev.c:4342 [inline]
__dev_queue_xmit+0x1b45/0x3820 net/core/dev.c:4884
dev_queue_xmit include/linux/netdevice.h:3461 [inline]
neigh_hh_output include/net/neighbour.h:544 [inline]
neigh_output include/net/neighbour.h:558 [inline]
ip_finish_output2+0xbda/0x10b0 net/ipv4/ip_output.c:236
NF_HOOK_COND include/linux/netfilter.h:314 [inline]
ip_output+0x29f/0x450 net/ipv4/ip_output.c:437
synproxy_send_client_synack+0x89b/0xde0 net/netfilter/nf_synproxy_core.c:487
nft_synproxy_eval_v4+0x362/0x4e0 net/netfilter/nft_synproxy.c:59
nft_synproxy_do_eval+0x335/0x550 net/netfilter/nft_synproxy.c:141
expr_call_ops_eval net/netfilter/nf_tables_core.c:237 [inline]
nft_do_chain+0x48d/0x1b10 net/netfilter/nf_tables_core.c:285
nft_do_chain_inet+0x360/0x4b0 net/netfilter/nft_chain_filter.c:162
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+0x21f/0x3c0 include/linux/netfilter.h:323
NF_HOOK+0x336/0x3c0 include/linux/netfilter.h:325
__netif_receive_skb_one_core net/core/dev.c:6264 [inline]
__netif_receive_skb net/core/dev.c:6377 [inline]
process_backlog+0xa6b/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
__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
blake2s include/crypto/blake2s.h:156 [inline]
compute_mac1+0x177/0x200 drivers/net/wireguard/cookie.c:80
wg_cookie_add_mac_to_packet+0x57/0x1a0 drivers/net/wireguard/cookie.c:163
wg_packet_send_handshake_response+0x128/0x2d0 drivers/net/wireguard/send.c:95
wg_receive_handshake_packet drivers/net/wireguard/receive.c:154 [inline]
wg_packet_handshake_receive_worker+0x6a9/0x10c0 drivers/net/wireguard/receive.c:213
process_one_work kernel/workqueue.c:3396 [inline]
process_scheduled_works+0xc3d/0x1630 kernel/workqueue.c:3479
worker_thread+0xa47/0xfb0 kernel/workqueue.c:3560
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