rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P6060/1:b..l
rcu: (detected by 0, t=10503 jiffies, g=205389, q=1558 ncpus=2)
task:syz-executor state:R running task stack:22264 pid:6060 tgid:6060 ppid:6041 task_flags:0x400140 flags:0x00080000
Call Trace:
context_switch kernel/sched/core.c:5260 [inline]
__schedule+0x1522/0x51d0 kernel/sched/core.c:6867
preempt_schedule_irq+0x4d/0xa0 kernel/sched/core.c:7194
irqentry_exit+0x597/0x620 kernel/entry/common.c:216
asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:697
RIP: 0010:lock_acquire+0x221/0x330 kernel/locking/lockdep.c:5872
Code: ff ff ff e8 41 d0 f6 09 f7 44 24 08 00 02 00 00 0f 84 3a ff ff ff 65 48 8b 05 2b 81 52 11 48 3b 44 24 58 75 33 fb 48 83 c4 60 <5b> 41 5c 41 5d 41 5e 41 5f 5d e9 d0 b5 f9 09 cc 48 8d 3d 58 1a 52
RSP: 0018:ffffc9000511ee38 EFLAGS: 00000282
RAX: 1968f0c1962f1200 RBX: 0000000000000000 RCX: 0000000000000046
RDX: 00000000a11fcbc3 RSI: ffffffff8df35112 RDI: ffffffff8c073b00
RBP: ffffffff81759195 R08: ffffffff81759195 R09: ffffffff8e55a360
R10: ffffc9000511ef98 R11: ffffffff81afb440 R12: 0000000000000002
R13: ffffffff8e55a360 R14: 0000000000000000 R15: 0000000000000246
rcu_lock_acquire include/linux/rcupdate.h:331 [inline]
rcu_read_lock include/linux/rcupdate.h:867 [inline]
class_rcu_constructor include/linux/rcupdate.h:1195 [inline]
unwind_next_frame+0xc2/0x23c0 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
save_stack+0x122/0x230 mm/page_owner.c:165
__set_page_owner+0x8d/0x4c0 mm/page_owner.c:341
set_page_owner include/linux/page_owner.h:32 [inline]
post_alloc_hook+0x228/0x280 mm/page_alloc.c:1884
prep_new_page mm/page_alloc.c:1892 [inline]
get_page_from_freelist+0x24dc/0x2580 mm/page_alloc.c:3945
__alloc_frozen_pages_noprof+0x18d/0x380 mm/page_alloc.c:5240
alloc_pages_mpol+0x232/0x4a0 mm/mempolicy.c:2486
alloc_frozen_pages_noprof mm/mempolicy.c:2557 [inline]
alloc_pages_noprof+0xa8/0x190 mm/mempolicy.c:2577
pagetable_alloc_noprof include/linux/mm.h:3194 [inline]
__pud_alloc_one_noprof include/asm-generic/pgalloc.h:181 [inline]
pud_alloc_one_noprof include/asm-generic/pgalloc.h:206 [inline]
__pud_alloc+0x3a/0x6e0 mm/memory.c:6645
pud_alloc include/linux/mm.h:3104 [inline]
copy_pud_range mm/memory.c:1409 [inline]
copy_p4d_range mm/memory.c:1453 [inline]
copy_page_range+0xc2b/0x11c0 mm/memory.c:1539
dup_mmap+0xf70/0x1bb0 mm/mmap.c:1827
dup_mm kernel/fork.c:1529 [inline]
copy_mm+0x13b/0x4b0 kernel/fork.c:1581
copy_process+0x166e/0x3980 kernel/fork.c:2221
kernel_clone+0x248/0x870 kernel/fork.c:2651
__do_sys_clone kernel/fork.c:2792 [inline]
__se_sys_clone kernel/fork.c:2776 [inline]
__x64_sys_clone+0x1b6/0x230 kernel/fork.c:2776
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0xe2/0xf80 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f0699bc3952
RSP: 002b:00007f0699f3fc60 EFLAGS: 00000246 ORIG_RAX: 0000000000000038
RAX: ffffffffffffffda RBX: 00007f0699f3fc60 RCX: 00007f0699bc3952
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000001200011
RBP: 00007f0699f3fdec R08: 0000000000000000 R09: 0000000000000001
R10: 0000555556c9b7d0 R11: 0000000000000246 R12: 0000000000000001
R13: 0000000000000059 R14: 000000000011ac6c R15: 00007f0699f3fe40
rcu: rcu_preempt kthread starved for 318 jiffies! g205389 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x0 ->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:I stack:27896 pid:16 tgid:16 ppid:2 task_flags:0x208040 flags:0x00080000
Call Trace:
context_switch kernel/sched/core.c:5260 [inline]
__schedule+0x1522/0x51d0 kernel/sched/core.c:6867
__schedule_loop kernel/sched/core.c:6949 [inline]
schedule+0x164/0x360 kernel/sched/core.c:6964
schedule_timeout+0x158/0x2c0 kernel/time/sleep_timeout.c:99
rcu_gp_fqs_loop+0x312/0x1560 kernel/rcu/tree.c:2083
rcu_gp_kthread+0x9d/0x3b0 kernel/rcu/tree.c:2285
kthread+0x726/0x8b0 kernel/kthread.c:463
ret_from_fork+0x51b/0xa40 arch/x86/kernel/process.c:158
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:246
rcu: Stack dump where RCU GP kthread last ran:
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 3567 Comm: kworker/u8:8 Tainted: G L syzkaller #0 PREEMPT(full)
Tainted: [L]=SOFTLOCKUP
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/24/2026
Workqueue: events_unbound toggle_allocation_gate
RIP: 0010:unwind_next_frame+0x4a5/0x23c0 arch/x86/kernel/unwind_orc.c:520
Code: e0 48 c1 e8 03 0f b6 04 28 84 c0 0f 85 66 18 00 00 4c 89 e8 48 c1 e8 03 0f b6 04 28 84 c0 0f 85 79 18 00 00 41 0f b6 44 24 01 <83> e0 07 0f 84 66 15 00 00 83 f8 01 4c 8b 7c 24 50 48 bd 00 00 00
RSP: 0018:ffffc90000a07db8 EFLAGS: 00000246
RAX: 0000000000000002 RBX: ffffffff9007c1d8 RCX: ffffffff9007c1dc
RDX: ffffffff90834c26 RSI: ffffffff90834c26 RDI: ffffffff8c073aa0
RBP: dffffc0000000000 R08: 0000000000000009 R09: ffffffff8e55a360
R10: ffffc90000a07ed8 R11: ffffffff81afb440 R12: ffffffff90834c2a
R13: ffffffff90834c2b R14: ffffc90000a07e88 R15: ffffffff9007c1d8
FS: 0000000000000000(0000) GS:ffff8881257f3000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f615f000218 CR3: 000000000e346000 CR4: 00000000003526f0
Call Trace:
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:340 [inline]
__kasan_slab_alloc+0x6c/0x80 mm/kasan/common.c:366
kasan_slab_alloc include/linux/kasan.h:253 [inline]
slab_post_alloc_hook mm/slub.c:4953 [inline]
slab_alloc_node mm/slub.c:5263 [inline]
kmem_cache_alloc_node_noprof+0x427/0x6f0 mm/slub.c:5315
__alloc_skb+0x1d7/0x390 net/core/skbuff.c:679
alloc_skb include/linux/skbuff.h:1383 [inline]
synproxy_send_client_synack+0x172/0xe30 net/netfilter/nf_synproxy_core.c:460
nft_synproxy_eval_v4+0x34a/0x4e0 net/netfilter/nft_synproxy.c:59
nft_synproxy_do_eval+0x305/0x580 net/netfilter/nft_synproxy.c:141
expr_call_ops_eval net/netfilter/nf_tables_core.c:237 [inline]
nft_do_chain+0x45e/0x1990 net/netfilter/nf_tables_core.c:285
nft_do_chain_inet+0x29d/0x380 net/netfilter/nft_chain_filter.c:161
nf_hook_entry_hookfn include/linux/netfilter.h:158 [inline]
nf_hook_slow+0xc5/0x220 net/netfilter/core.c:623
nf_hook include/linux/netfilter.h:273 [inline]
NF_HOOK+0x21f/0x3c0 include/linux/netfilter.h:316
NF_HOOK+0x336/0x3c0 include/linux/netfilter.h:318
__netif_receive_skb_one_core net/core/dev.c:6152 [inline]
__netif_receive_skb net/core/dev.c:6265 [inline]
process_backlog+0xaa3/0x1950 net/core/dev.c:6617
__napi_poll+0xae/0x340 net/core/dev.c:7681
napi_poll net/core/dev.c:7744 [inline]
net_rx_action+0x627/0xf70 net/core/dev.c:7896
handle_softirqs+0x22a/0x7c0 kernel/softirq.c:622
__do_softirq kernel/softirq.c:656 [inline]
invoke_softirq kernel/softirq.c:496 [inline]
__irq_exit_rcu+0x5f/0x150 kernel/softirq.c:723
irq_exit_rcu+0x9/0x30 kernel/softirq.c:739
instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1056 [inline]
sysvec_apic_timer_interrupt+0xa6/0xc0 arch/x86/kernel/apic/apic.c:1056
asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:697
RIP: 0010:csd_lock_wait kernel/smp.c:342 [inline]
RIP: 0010:smp_call_function_many_cond+0xce5/0x1270 kernel/smp.c:877
Code: 45 8b 2c 24 44 89 ee 83 e6 01 31 ff e8 c4 db 0b 00 41 83 e5 01 49 bd 00 00 00 00 00 fc ff df 75 07 e8 6f d7 0b 00 eb 38 f3 90 <42> 0f b6 04 2b 84 c0 75 11 41 f7 04 24 01 00 00 00 74 1e e8 53 d7
RSP: 0018:ffffc9000c29f6a0 EFLAGS: 00000293
RAX: ffffffff81b8a2cd RBX: 1ffff110170c856d RCX: ffff888031699e80
RDX: 0000000000000000 RSI: 0000000000000001 RDI: 0000000000000000
RBP: ffffc9000c29f7e0 R08: ffffffff8fef2077 R09: 1ffffffff1fde40e
R10: dffffc0000000000 R11: fffffbfff1fde40f R12: ffff8880b8642b68
R13: dffffc0000000000 R14: ffff8880b873bb00 R15: 0000000000000000
on_each_cpu_cond_mask+0x3f/0x80 kernel/smp.c:1043
on_each_cpu include/linux/smp.h:71 [inline]
smp_text_poke_sync_each_cpu arch/x86/kernel/alternative.c:2711 [inline]
smp_text_poke_batch_finish+0x5f5/0x1160 arch/x86/kernel/alternative.c:2921
arch_jump_label_transform_apply+0x1c/0x30 arch/x86/kernel/jump_label.c:146
static_key_enable_cpuslocked+0x128/0x240 kernel/jump_label.c:210
static_key_enable+0x1a/0x20 kernel/jump_label.c:223
toggle_allocation_gate+0xab/0x290 mm/kfence/core.c:894
process_one_work kernel/workqueue.c:3257 [inline]
process_scheduled_works+0xaec/0x17a0 kernel/workqueue.c:3340
worker_thread+0xda6/0x1360 kernel/workqueue.c:3421
kthread+0x726/0x8b0 kernel/kthread.c:463
ret_from_fork+0x51b/0xa40 arch/x86/kernel/process.c:158
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:246