rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 	0-...!: (3 ticks this GP) idle=4acc/1/0x4000000000000000 softirq=127421/127423 fqs=3
rcu: 	(detected by 1, t=10502 jiffies, g=126109, q=87 ncpus=2)
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 21701 Comm: syz.5.5149 Not tainted syzkaller #0 PREEMPT(full) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/18/2025
RIP: 0010:pv_queued_spin_unlock arch/x86/include/asm/paravirt.h:562 [inline]
RIP: 0010:queued_spin_unlock arch/x86/include/asm/qspinlock.h:57 [inline]
RIP: 0010:do_raw_spin_unlock+0xfe/0x240 kernel/locking/spinlock_debug.c:142
Code: 06 ff ff ff ff 42 0f b6 44 25 00 84 c0 0f 85 29 01 00 00 41 c7 07 ff ff ff ff 48 c7 c0 38 8c 1a 8e 48 c1 e8 03 42 80 3c 20 00 <74> 0c 48 c7 c7 38 8c 1a 8e e8 54 53 86 00 48 83 3d 34 6a 7c 0c 00
RSP: 0018:ffffc90000007c68 EFLAGS: 00000046
RAX: 1ffffffff1c35187 RBX: ffff8880b8627ac0 RCX: 0000000000000000
RDX: 0000000000000000 RSI: 0000000000000004 RDI: ffff8880b8627ac0
RBP: 1ffff110170c4f59 R08: ffff8880b8627ac3 R09: 1ffff110170c4f58
R10: dffffc0000000000 R11: ffffed10170c4f59 R12: dffffc0000000000
R13: 1ffff110170c4f5a R14: ffff8880b8627ad0 R15: ffff8880b8627ac8
FS:  00007f657bbad6c0(0000) GS:ffff8881259e7000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00002000000f9030 CR3: 00000000648b4000 CR4: 00000000003526f0
Call Trace:
 <IRQ>
 __raw_spin_unlock_irqrestore include/linux/spinlock_api_smp.h:150 [inline]
 _raw_spin_unlock_irqrestore+0x78/0x110 kernel/locking/spinlock.c:194
 __run_hrtimer kernel/time/hrtimer.c:1773 [inline]
 __hrtimer_run_queues+0x408/0xc60 kernel/time/hrtimer.c:1841
 hrtimer_interrupt+0x45b/0xaa0 kernel/time/hrtimer.c:1903
 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1041 [inline]
 __sysvec_apic_timer_interrupt+0x10b/0x410 arch/x86/kernel/apic/apic.c:1058
 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1052 [inline]
 sysvec_apic_timer_interrupt+0xa1/0xc0 arch/x86/kernel/apic/apic.c:1052
 </IRQ>
 <TASK>
 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:697
RIP: 0010:sized_strscpy+0x0/0x250 lib/string.c:114
Code: 8b 74 24 08 48 8b 04 24 e9 96 fe ff ff 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 55 41 57 41 56 41 55 41 54 53 50 48 c7 c3 f9 ff ff ff
RSP: 0018:ffffc9000c696c58 EFLAGS: 00000286
RAX: ffffffff822ddb29 RBX: ffff88801ee4b9b8 RCX: ffff88802eb91e40
RDX: 000000000000000b RSI: ffff88802eb92740 RDI: ffff88801ee4b9b8
RBP: ffff88801ee4b990 R08: 0000000000000000 R09: ffffffff822dd89a
R10: ffff88802eb92740 R11: ffffffff81ac5170 R12: 000000000000000b
R13: 0000000000000000 R14: 000000000000000a R15: 0000000000000000
 sized_strscpy include/linux/fortify-string.h:329 [inline]
 __update_page_owner_handle+0x307/0x570 mm/page_owner.c:253
 __set_page_owner+0x10b/0x4a0 mm/page_owner.c:330
 set_page_owner include/linux/page_owner.h:32 [inline]
 post_alloc_hook+0x240/0x2a0 mm/page_alloc.c:1850
 prep_new_page mm/page_alloc.c:1858 [inline]
 get_page_from_freelist+0x21e4/0x22c0 mm/page_alloc.c:3869
 __alloc_frozen_pages_noprof+0x181/0x370 mm/page_alloc.c:5159
 alloc_pages_mpol+0x232/0x4a0 mm/mempolicy.c:2416
 folio_alloc_mpol_noprof mm/mempolicy.c:2435 [inline]
 vma_alloc_folio_noprof+0xe4/0x200 mm/mempolicy.c:2470
 folio_prealloc+0x30/0x180 mm/memory.c:-1
 wp_page_copy mm/memory.c:3723 [inline]
 do_wp_page+0x1231/0x5800 mm/memory.c:4184
 handle_pte_fault mm/memory.c:6242 [inline]
 __handle_mm_fault+0x1033/0x5400 mm/memory.c:6367
 handle_mm_fault+0x40a/0x8e0 mm/memory.c:6536
 do_user_addr_fault+0x764/0x1380 arch/x86/mm/fault.c:1387
 handle_page_fault arch/x86/mm/fault.c:1476 [inline]
 exc_page_fault+0x82/0x100 arch/x86/mm/fault.c:1532
 asm_exc_page_fault+0x26/0x30 arch/x86/include/asm/idtentry.h:618
RIP: 0010:__put_user_nocheck_4+0x3/0x10 arch/x86/lib/putuser.S:104
Code: d9 0f 01 cb 89 01 31 c9 0f 01 ca c3 cc cc cc cc 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 0f 01 cb <89> 01 31 c9 0f 01 ca e9 d1 64 03 00 90 90 90 90 90 90 90 90 90 90
RSP: 0018:ffffc9000c6978b8 EFLAGS: 00050202
RAX: 0000000000000000 RBX: 0000000000000000 RCX: 00002000000f9030
RDX: ffff88802eb91e40 RSI: 0000000000000002 RDI: 00000000ffffffff
RBP: ffffc9000c697a30 R08: ffffc9000c697667 R09: 1ffff920018d2ecc
R10: dffffc0000000000 R11: fffff520018d2ecd R12: 0000000000000002
R13: dffffc0000000000 R14: 0000000000000000 R15: 00002000000f9000
 ____sys_recvmsg+0x2ab/0x460 net/socket.c:2850
 ___sys_recvmsg+0x1b5/0x510 net/socket.c:2879
 do_recvmmsg+0x307/0x770 net/socket.c:2974
 __sys_recvmmsg net/socket.c:3048 [inline]
 __do_sys_recvmmsg net/socket.c:3071 [inline]
 __se_sys_recvmmsg net/socket.c:3064 [inline]
 __x64_sys_recvmmsg+0x190/0x240 net/socket.c:3064
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xfa/0xfa0 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f657ad8ec29
Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 a8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007f657bbad038 EFLAGS: 00000246 ORIG_RAX: 000000000000012b
RAX: ffffffffffffffda RBX: 00007f657afd6090 RCX: 00007f657ad8ec29
RDX: 0000000000010106 RSI: 00002000000000c0 RDI: 0000000000000004
RBP: 00007f657ae11e41 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000002 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f657afd6128 R14: 00007f657afd6090 R15: 00007ffe83113138
 </TASK>
rcu: rcu_preempt kthread starved for 10496 jiffies! g126109 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:R  running task     stack:26464 pid:16    tgid:16    ppid:2      task_flags:0x208040 flags:0x00080000
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5360 [inline]
 __schedule+0x1798/0x4cc0 kernel/sched/core.c:6964
 __schedule_loop kernel/sched/core.c:7046 [inline]
 schedule+0x165/0x360 kernel/sched/core.c:7061
 schedule_timeout+0x12b/0x270 kernel/time/sleep_timeout.c:99
 rcu_gp_fqs_loop+0x301/0x1540 kernel/rcu/tree.c:2083
 rcu_gp_kthread+0x99/0x390 kernel/rcu/tree.c:2285
 kthread+0x711/0x8a0 kernel/kthread.c:463
 ret_from_fork+0x4bc/0x870 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: 18571 Comm: kworker/u8:8 Not tainted syzkaller #0 PREEMPT(full) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/18/2025
Workqueue: events_unbound toggle_allocation_gate
RIP: 0010:csd_lock_wait kernel/smp.c:342 [inline]
RIP: 0010:smp_call_function_many_cond+0xd44/0x12d0 kernel/smp.c:877
Code: 41 83 e5 01 49 bd 00 00 00 00 00 fc ff df 75 07 e8 e1 74 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 c5 74 0b 00 eb e4 44 89 e1 80 e1 07 80 c1 03 38 c1 7c e2
RSP: 0018:ffffc900036df640 EFLAGS: 00000202
RAX: 0000000000000000 RBX: 1ffff110170c8441 RCX: ffff888021333c80
RDX: 0000000000000000 RSI: 0000000000000001 RDI: 0000000000000000
RBP: ffffc900036df7c0 R08: ffffffff8fc39677 R09: 1ffffffff1f872ce
R10: dffffc0000000000 R11: fffffbfff1f872cf R12: ffff8880b8642208
R13: dffffc0000000000 R14: ffff8880b873b200 R15: 0000000000000000
FS:  0000000000000000(0000) GS:ffff888125ae7000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f657ad72060 CR3: 000000000e138000 CR4: 00000000003526f0
DR0: 0000000000000008 DR1: 0000000000000002 DR2: 0000000000000081
DR3: ffffffffefffff14 DR6: 00000000ffff0ff0 DR7: 0000000000000400
Call Trace:
 <TASK>
 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:2713 [inline]
 smp_text_poke_batch_finish+0x5f9/0x1130 arch/x86/kernel/alternative.c:2923
 arch_jump_label_transform_apply+0x1c/0x30 arch/x86/kernel/jump_label.c:146
 static_key_enable_cpuslocked+0x128/0x250 kernel/jump_label.c:210
 static_key_enable+0x1a/0x20 kernel/jump_label.c:223
 toggle_allocation_gate+0xad/0x240 mm/kfence/core.c:852
 process_one_work kernel/workqueue.c:3263 [inline]
 process_scheduled_works+0xae1/0x17b0 kernel/workqueue.c:3346
 worker_thread+0x8a0/0xda0 kernel/workqueue.c:3427
 kthread+0x711/0x8a0 kernel/kthread.c:463
 ret_from_fork+0x4bc/0x870 arch/x86/kernel/process.c:158
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
 </TASK>