rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P8631/1:b..l..
rcu: (detected by 0, t=10503 jiffies, g=34709, q=853417 ncpus=2)
task:syz.1.769 state:R running task stack:26360 pid:8631 tgid:8628 ppid:5632 task_flags:0x400040 flags:0x00080002
Call Trace:
context_switch kernel/sched/core.c:5583 [inline]
__schedule+0x17dd/0x5830 kernel/sched/core.c:7382
preempt_schedule_irq+0x4b/0x90 kernel/sched/core.c:7662
irqentry_exit_to_kernel_mode include/linux/irq-entry-common.h:543 [inline]
irqentry_exit+0x14f/0x9b0 kernel/entry/common.c:154
asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:674
RIP: 0010:__orc_find arch/x86/kernel/unwind_orc.c:101 [inline]
RIP: 0010:orc_find arch/x86/kernel/unwind_orc.c:238 [inline]
RIP: 0010:unwind_next_frame+0x4c3/0x2550 arch/x86/kernel/unwind_orc.c:510
Code: 01 4c 8b 6c 24 50 49 bc 00 00 00 00 00 fc ff df 4c 8b 7c 24 10 49 8d 6e 38 0f 84 8a 16 00 00 e9 ee 01 00 00 49 89 d5 49 89 d7 <4c> 89 e0 4c 29 f8 48 89 c1 48 c1 f9 02 48 c1 e8 3f 48 01 c8 48 83
RSP: 0018:ffffc9000810f100 EFLAGS: 00000246
RAX: ffffffff92671500 RBX: dffffc0000000000 RCX: 8000000000000000
RDX: ffffffff91e1dfc4 RSI: ffffffff926715b0 RDI: ffffffff8c8ea020
RBP: ffffffff82533b6f R08: 0000000000000001 R09: 0000000000000000
R10: ffffc9000810f1f8 R11: ffffffff81b3ad40 R12: ffffffff91e1dfc4
R13: ffffffff91e1dfc4 R14: ffffc9000810f1a8 R15: ffffffff91e1dfc4
arch_stack_walk+0x11b/0x150 arch/x86/kernel/stacktrace.c:25
stack_trace_save+0xa9/0x100 kernel/stacktrace.c:122
save_stack+0x122/0x230 mm/page_owner.c:183
__set_page_owner+0x8d/0x4c0 mm/page_owner.c:359
set_page_owner include/linux/page_owner.h:33 [inline]
post_alloc_hook+0x1f9/0x250 mm/page_alloc.c:1856
prep_new_page mm/page_alloc.c:1864 [inline]
get_page_from_freelist+0x220f/0x2280 mm/page_alloc.c:3935
__alloc_frozen_pages_noprof+0x1fe/0x410 mm/page_alloc.c:5459
alloc_pages_mpol+0x21e/0x390 mm/mempolicy.c:2511
folio_alloc_mpol_noprof+0x39/0x160 mm/mempolicy.c:2530
shmem_alloc_folio mm/shmem.c:2141 [inline]
shmem_alloc_and_add_folio+0x43e/0xf60 mm/shmem.c:2183
shmem_get_folio_gfp+0x594/0x1330 mm/shmem.c:2736
shmem_get_folio mm/shmem.c:2835 [inline]
shmem_write_begin+0x16c/0x330 mm/shmem.c:3470
generic_perform_write+0x2d5/0x8e0 mm/filemap.c:4392
shmem_file_write_iter+0xf8/0x120 mm/shmem.c:3645
new_sync_write fs/read_write.c:595 [inline]
vfs_write+0x612/0xba0 fs/read_write.c:687
ksys_write+0x150/0x270 fs/read_write.c:1036
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: 0033:0x7fa7b395fd8e
RSP: 002b:00007fa7b48bfda8 EFLAGS: 00000246 ORIG_RAX: 0000000000000001
RAX: ffffffffffffffda RBX: 00007fa7b48c06c0 RCX: 00007fa7b395fd8e
RDX: 0000000000100000 RSI: 00007fa7a9600000 RDI: 0000000000000006
RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000006
R13: 00007fa7b48bfee0 R14: 00007fa7b48bfea0 R15: 00007fa7a9600000
rcu: rcu_preempt kthread starved for 603 jiffies! g34709 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:27696 pid:16 tgid:16 ppid:2 task_flags:0x208040 flags:0x00080000
Call Trace:
context_switch kernel/sched/core.c:5583 [inline]
__schedule+0x17dd/0x5830 kernel/sched/core.c:7382
__schedule_loop kernel/sched/core.c:7459 [inline]
schedule+0x164/0x2b0 kernel/sched/core.c:7474
schedule_timeout+0x152/0x2c0 kernel/time/sleep_timeout.c:99
rcu_gp_fqs_loop+0x30c/0x1230 kernel/rcu/tree.c:2122
rcu_gp_kthread+0x9c/0x340 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: 3831 Comm: kworker/0:2 Not tainted syzkaller #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/07/2026
Workqueue: wg-kex-wg0 wg_packet_handshake_receive_worker
RIP: 0010:check_preemption_disabled+0x3/0xd0 lib/smp_processor_id.c:13
Code: 8e 8c 48 c7 c6 60 a0 8e 8c eb 1c 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 55 41 57 <41> 56 53 65 8b 05 eb 2b dd 08 65 48 8b 0d bb 2b dd 08 85 c9 74 0c
RSP: 0018:ffffc90000006c28 EFLAGS: 00000282
RAX: 0000000000000001 RBX: ffffc90000006d18 RCX: ffff888026223e80
RDX: ffffc90000006d01 RSI: ffffffff8c8ea060 RDI: ffffffff8c8ea020
RBP: 1ffffffff25c6701 R08: ffffc90000007f50 R09: 0000000000000000
R10: ffffc90000006d58 R11: fffff52000000dad R12: ffffc90000000000
R13: ffffffff8178798f R14: ffffc90000006d08 R15: ffffc90000007f60
FS: 0000000000000000(0000) GS:ffff888123411000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fff0f065ff8 CR3: 000000000ff48000 CR4: 00000000003526f0
Call Trace:
rcu_is_watching_curr_cpu include/linux/context_tracking.h:128 [inline]
rcu_is_watching+0x16/0xb0 kernel/rcu/tree.c:753
rcu_read_unlock include/linux/rcupdate.h:878 [inline]
class_rcu_destructor include/linux/rcupdate.h:1216 [inline]
unwind_next_frame+0x1b66/0x2550 arch/x86/kernel/unwind_orc.c:709
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
unpoison_slab_object mm/kasan/common.c:351 [inline]
__kasan_slab_alloc+0x6c/0x80 mm/kasan/common.c:377
kasan_slab_alloc include/linux/kasan.h:253 [inline]
slab_post_alloc_hook mm/slub.c:4720 [inline]
slab_alloc_node mm/slub.c:5033 [inline]
kmem_cache_alloc_noprof+0x2b4/0x600 mm/slub.c:5047
kmem_alloc_batch lib/debugobjects.c:371 [inline]
fill_pool+0x163/0x610 lib/debugobjects.c:420
debug_objects_fill_pool lib/debugobjects.c:780 [inline]
debug_object_activate+0x38d/0x420 lib/debugobjects.c:869
debug_rcu_head_queue kernel/rcu/rcu.h:245 [inline]
rcu_do_enqueue+0x2a/0x870 kernel/rcu/tree.c:3164
__call_rcu_common kernel/rcu/tree.c:3300 [inline]
call_rcu+0x20e/0x300 kernel/rcu/tree.c:3395
refdst_drop include/net/dst.h:272 [inline]
skb_dst_drop include/net/dst.h:284 [inline]
skb_release_head_state+0x71/0x370 net/core/skbuff.c:1162
skb_release_all net/core/skbuff.c:1186 [inline]
__kfree_skb+0x24/0x210 net/core/skbuff.c:1202
nft_synproxy_eval_v4+0x36a/0x4e0 net/netfilter/nft_synproxy.c:-1
nft_synproxy_do_eval+0x389/0x5d0 net/netfilter/nft_synproxy.c:142
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:633
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:6405 [inline]
__netif_receive_skb net/core/dev.c:6518 [inline]
process_backlog+0xa6b/0x18b0 net/core/dev.c:6869
__napi_poll+0xaa/0x330 net/core/dev.c:7938
napi_poll net/core/dev.c:8001 [inline]
net_rx_action+0x61d/0xf50 net/core/dev.c:8158
handle_softirqs+0x265/0x8d0 kernel/softirq.c:669
do_softirq+0x77/0xd0 kernel/softirq.c:569
__local_bh_enable_ip+0x100/0x140 kernel/softirq.c:473
blake2s_compress+0xfa/0x1c00 lib/crypto/x86/blake2s.h:42
blake2s_final+0x10f/0x270 lib/crypto/blake2s.c:142
blake2s include/crypto/blake2s.h:166 [inline]
compute_mac1+0x184/0x200 drivers/net/wireguard/cookie.c:80
wg_cookie_validate_packet+0x143/0x380 drivers/net/wireguard/cookie.c:130
wg_receive_handshake_packet drivers/net/wireguard/receive.c:121 [inline]
wg_packet_handshake_receive_worker+0x4cb/0x10b0 drivers/net/wireguard/receive.c:213
process_one_work kernel/workqueue.c:3495 [inline]
process_scheduled_works+0xc3d/0x1630 kernel/workqueue.c:3578
worker_thread+0xa47/0xfb0 kernel/workqueue.c:3659
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