rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 	1-...!: (1 GPs behind) idle=459c/1/0x4000000000000000 softirq=74233/74236 fqs=3
rcu: 	(detected by 0, t=10502 jiffies, g=74773, q=307 ncpus=2)
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 17113 Comm: syz.4.4101 Not tainted syzkaller #0 PREEMPT(full) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/18/2025
RIP: 0010:debug_object_deactivate+0x3f/0x250 lib/debugobjects.c:863
Code: 49 89 fc 65 48 8b 05 a0 a0 b9 0d 48 89 44 24 30 48 8d 7c 24 08 ba 10 00 00 00 31 f6 e8 7a 23 95 fd 48 c7 44 24 18 05 00 00 00 <4c> 89 64 24 20 48 89 5c 24 28 80 3d 88 c1 cc 0a 00 0f 85 43 01 00
RSP: 0018:ffffc90000a08ca8 EFLAGS: 00000002
RAX: ffffc90000a08cb0 RBX: ffffffff8b4cf860 RCX: 0000000000000000
RDX: 0000000000000010 RSI: 0000000000000000 RDI: ffffc90000a08cc0
RBP: ffffc90000a08e90 R08: ffffc90000a08cbf R09: ffffc90000a08cb0
R10: dffffc0000000000 R11: fffff52000141198 R12: ffff88804db17340
R13: dffffc0000000000 R14: 1872045fe4811672 R15: ffff8880b8927bc0
FS:  0000000000000000(0000) GS:ffff888126496000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000001b2f422ff8 CR3: 00000000607c1000 CR4: 0000000000350ef0
Call Trace:
 <IRQ>
 debug_hrtimer_deactivate kernel/time/hrtimer.c:443 [inline]
 debug_deactivate+0x1d/0x200 kernel/time/hrtimer.c:483
 __run_hrtimer kernel/time/hrtimer.c:1745 [inline]
 __hrtimer_run_queues+0x2b0/0xc60 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:702
RIP: 0010:pfn_valid+0x1d1/0x490 include/linux/mmzone.h:2196
Code: e9 55 ff ff ff 43 80 7c 25 00 00 74 08 4c 89 ff e8 14 ce f4 ff 4d 8b 2f 4c 89 ee 48 83 e6 08 31 ff e8 43 31 8f ff 49 83 e5 08 <0f> 85 8b 00 00 00 49 83 c7 08 4c 89 f8 48 c1 e8 03 42 80 3c 20 00
RSP: 0018:ffffc9001c3c7558 EFLAGS: 00000202
RAX: ffffffff822f523d RBX: ffffffff822f512a RCX: ffff88802e041e40
RDX: 0000000000000000 RSI: 0000000000000008 RDI: 0000000000000000
RBP: 0000000000000002 R08: 0000000000000000 R09: ffffffff822f512a
R10: dffffc0000000000 R11: fffff940003c6c21 R12: dffffc0000000000
R13: 0000000000000008 R14: 0000000000078d84 R15: ffff88813fffa5e0
 page_table_check_clear+0x21/0x700 mm/page_table_check.c:70
 ptep_get_and_clear_full arch/x86/include/asm/jump_label.h:-1 [inline]
 get_and_clear_full_ptes include/linux/pgtable.h:725 [inline]
 zap_present_folio_ptes mm/memory.c:1627 [inline]
 zap_present_ptes mm/memory.c:1709 [inline]
 do_zap_pte_range mm/memory.c:1810 [inline]
 zap_pte_range mm/memory.c:1854 [inline]
 zap_pmd_range mm/memory.c:1946 [inline]
 zap_pud_range mm/memory.c:1975 [inline]
 zap_p4d_range mm/memory.c:1996 [inline]
 unmap_page_range+0x344b/0x4370 mm/memory.c:2017
 unmap_single_vma mm/memory.c:2060 [inline]
 unmap_vmas+0x399/0x580 mm/memory.c:2104
 exit_mmap+0x240/0xb40 mm/mmap.c:1280
 __mmput+0x118/0x430 kernel/fork.c:1133
 exit_mm+0x1da/0x2c0 kernel/exit.c:582
 do_exit+0x648/0x2300 kernel/exit.c:954
 do_group_exit+0x21c/0x2d0 kernel/exit.c:1107
 __do_sys_exit_group kernel/exit.c:1118 [inline]
 __se_sys_exit_group kernel/exit.c:1116 [inline]
 __x64_sys_exit_group+0x3f/0x40 kernel/exit.c:1116
 x64_sys_call+0x21f7/0x2200 arch/x86/include/generated/asm/syscalls_64.h:232
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xfa/0x3b0 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fabaab8eec9
Code: Unable to access opcode bytes at 0x7fabaab8ee9f.
RSP: 002b:00007ffeafb41738 EFLAGS: 00000246 ORIG_RAX: 00000000000000e7
RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007fabaab8eec9
RDX: 0000000000000064 RSI: 0000000000000000 RDI: 0000000000000000
RBP: 00007ffeafb4179c R08: 00000004afb4182f R09: 00000000000927c0
R10: 0000000000000001 R11: 0000000000000246 R12: 00000000000000ba
R13: 00000000000927c0 R14: 0000000000079ae2 R15: 00007ffeafb417f0
 </TASK>
rcu: rcu_preempt kthread starved for 10496 jiffies! g74773 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:26312 pid:16    tgid:16    ppid:2      task_flags:0x208040 flags:0x00080000
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5325 [inline]
 __schedule+0x1798/0x4cc0 kernel/sched/core.c:6929
 __schedule_loop kernel/sched/core.c:7011 [inline]
 schedule+0x165/0x360 kernel/sched/core.c:7026
 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+0x439/0x7d0 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:
CPU: 0 UID: 0 PID: 36 Comm: kworker/u8:2 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+0xd33/0x12d0 kernel/smp.c:877
Code: 45 8b 2c 24 44 89 ee 83 e6 01 31 ff e8 56 72 0b 00 41 83 e5 01 49 bd 00 00 00 00 00 fc ff df 75 07 e8 01 6e 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 e5 6d
RSP: 0018:ffffc90000ac7660 EFLAGS: 00000293
RAX: ffffffff81b310bb RBX: 1ffff11017127ff5 RCX: ffff88801ced1e40
RDX: 0000000000000000 RSI: 0000000000000001 RDI: 0000000000000000
RBP: ffffc90000ac77e0 R08: ffffffff8f5b9137 R09: 1ffffffff1eb7226
R10: dffffc0000000000 R11: fffffbfff1eb7227 R12: ffff8880b893ffa8
R13: dffffc0000000000 R14: ffff8880b883b200 R15: 0000000000000001
FS:  0000000000000000(0000) GS:ffff888126396000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000001b3151eff8 CR3: 000000000db36000 CR4: 0000000000350ef0
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:2653 [inline]
 smp_text_poke_batch_finish+0x5f9/0x1130 arch/x86/kernel/alternative.c:2863
 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+0x439/0x7d0 arch/x86/kernel/process.c:148
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
 </TASK>