rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 	0-...!: (1 GPs behind) idle=354c/1/0x4000000000000000 softirq=15290/15300 fqs=1
rcu: 	(detected by 1, t=10502 jiffies, g=10757, q=188 ncpus=2)
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 6118 Comm: dhcpcd-run-hook Not tainted syzkaller #0 PREEMPT(full) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025
RIP: 0010:__lock_is_held kernel/locking/lockdep.c:5598 [inline]
RIP: 0010:lock_is_held_type+0xb6/0x190 kernel/locking/lockdep.c:5940
Code: eb 48 81 c3 30 0b 00 00 45 31 ff 49 83 ff 31 73 24 48 89 df 4c 89 f6 e8 78 02 00 00 85 c0 75 2a 49 ff c7 49 63 85 28 0b 00 00 <48> 83 c3 28 49 39 c7 7c d8 eb 11 48 c7 c7 70 df 20 8e 4c 89 fe e8
RSP: 0018:ffffc90000007c28 EFLAGS: 00000002
RAX: 0000000000000002 RBX: ffff88802a4f8b30 RCX: 6064536a89a12a00
RDX: ffff88802a4f8000 RSI: ffff88802fc03300 RDI: ffff88802a4f8b30
RBP: 00000000ffffffff R08: 0000000000000003 R09: 0000000000000004
R10: dffffc0000000000 R11: fffff52000000f7c R12: 0000000000000046
R13: ffff88802a4f8000 R14: ffff88802fc03300 R15: 0000000000000001
FS:  0000000000000000(0000) GS:ffff8881259f9000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f37d983b000 CR3: 00000000304d2000 CR4: 00000000003526f0
Call Trace:
 <IRQ>
 lock_is_held include/linux/lockdep.h:249 [inline]
 advance_sched+0x160/0xc90 net/sched/sch_taprio.c:932
 __run_hrtimer kernel/time/hrtimer.c:1761 [inline]
 __hrtimer_run_queues+0x529/0xc60 kernel/time/hrtimer.c:1825
 hrtimer_interrupt+0x45b/0xaa0 kernel/time/hrtimer.c:1887
 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1041 [inline]
 __sysvec_apic_timer_interrupt+0x108/0x410 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:rcu_lockdep_current_cpu_online+0x0/0x120 kernel/rcu/tree.c:4025
Code: 34 8e e8 b3 bb 5a 03 89 df e9 4e ff ff ff 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 41 57 41 56 53 65 8b 0d e0 c4 1a 11 b0 01 f7 c1 00 00
RSP: 0018:ffffc9000487f5d8 EFLAGS: 00000202
RAX: 0000000000000001 RBX: 0000000000000000 RCX: 6064536a89a12a00
RDX: ffff88802a4f8000 RSI: ffffffff8c0371e0 RDI: ffffffff8c0371a0
RBP: ffffc9000487f670 R08: ffffffff8fc3ee37 R09: 1ffffffff1f87dc6
R10: dffffc0000000000 R11: fffffbfff1f87dc7 R12: ffff8880344dc350
R13: ffff8880344dc000 R14: 1ffff9200090febc R15: dffffc0000000000
 rcu_read_lock_held_common kernel/rcu/update.c:113 [inline]
 rcu_read_lock_any_held+0x74/0x120 kernel/rcu/update.c:384
 rcu_sync_is_idle include/linux/rcu_sync.h:34 [inline]
 percpu_down_read_trylock include/linux/percpu-rwsem.h:94 [inline]
 __sb_start_write_trylock include/linux/fs.h:1797 [inline]
 sb_start_write_trylock include/linux/fs.h:1933 [inline]
 touch_atime+0xd2/0x6d0 fs/inode.c:2134
 file_accessed include/linux/fs.h:2657 [inline]
 ext4_file_mmap_prepare+0x24d/0x440 fs/ext4/file.c:828
 vfs_mmap_prepare include/linux/fs.h:2288 [inline]
 call_mmap_prepare mm/vma.c:2585 [inline]
 __mmap_region mm/vma.c:2653 [inline]
 mmap_region+0xb3b/0x2100 mm/vma.c:2739
 do_mmap+0xc45/0x10d0 mm/mmap.c:558
 vm_mmap_pgoff+0x2a6/0x4d0 mm/util.c:580
 ksys_mmap_pgoff+0x51f/0x760 mm/mmap.c:604
 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: 0033:0x7f37d9866242
Code: 08 00 04 00 00 eb e2 90 41 f7 c1 ff 0f 00 00 75 27 55 89 cd 53 48 89 fb 48 85 ff 74 33 41 89 ea 48 89 df b8 09 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 5e 5b 5d c3 0f 1f 00 c7 05 46 40 01 00 16 00
RSP: 002b:00007fff626043d8 EFLAGS: 00000206 ORIG_RAX: 0000000000000009
RAX: ffffffffffffffda RBX: 00007f37d958a000 RCX: 00007f37d9866242
RDX: 0000000000000005 RSI: 0000000000008000 RDI: 00007f37d958a000
RBP: 0000000000000812 R08: 0000000000000003 R09: 0000000000003000
R10: 0000000000000812 R11: 0000000000000206 R12: 00007fff62604428
R13: 00007f37d983ab20 R14: 00007fff62604810 R15: 00000fffec4c087e
 </TASK>
rcu: rcu_preempt kthread starved for 10500 jiffies! g10757 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:27256 pid:16    tgid:16    ppid:2      task_flags:0x208040 flags:0x00004000
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+0x70e/0x8a0 kernel/kthread.c:463
 ret_from_fork+0x47c/0x820 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: 1 UID: 0 PID: 12 Comm: kworker/u8:0 Not tainted syzkaller #0 PREEMPT(full) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025
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 16 77 0b 00 41 83 e5 01 49 bd 00 00 00 00 00 fc ff df 75 07 e8 c1 72 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 a5 72
RSP: 0018:ffffc90000117640 EFLAGS: 00000293
RAX: ffffffff81b5531b RBX: 1ffff110170c8355 RCX: ffff88801d68dac0
RDX: 0000000000000000 RSI: 0000000000000001 RDI: 0000000000000000
RBP: ffffc900001177c0 R08: ffffffff8fc3ee37 R09: 1ffffffff1f87dc6
R10: dffffc0000000000 R11: fffffbfff1f87dc7 R12: ffff8880b8641aa8
R13: dffffc0000000000 R14: ffff8880b873b1c0 R15: 0000000000000000
FS:  0000000000000000(0000) GS:ffff888125af9000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f15ba518e9c CR3: 000000000e138000 CR4: 00000000003526f0
Call Trace:
 <TASK>
 on_each_cpu_cond_mask+0x3f/0x80 kernel/smp.c:1044
 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+0xade/0x17b0 kernel/workqueue.c:3346
 worker_thread+0x8a0/0xda0 kernel/workqueue.c:3427
 kthread+0x70e/0x8a0 kernel/kthread.c:463
 ret_from_fork+0x47c/0x820 arch/x86/kernel/process.c:148
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
 </TASK>
sched: DL replenish lagged too much