rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 	0-...!: (0 ticks this GP) idle=af94/1/0x4000000000000000 softirq=157638/157638 fqs=0
rcu: 	(detected by 1, t=10505 jiffies, g=125873, q=188 ncpus=2)
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 15543 Comm: syz.3.12615 Not tainted 6.15.0-rc4-syzkaller-00291-g2a239ffbebb5 #0 PREEMPT(full) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/19/2025
RIP: 0010:arch_test_bit arch/x86/include/asm/bitops.h:239 [inline]
RIP: 0010:_test_bit include/asm-generic/bitops/instrumented-non-atomic.h:142 [inline]
RIP: 0010:hlock_class+0x8/0x70 kernel/locking/lockdep.c:233
Code: 01 ff ff ff 66 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 00 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 0f b7 47 20 66 25 ff 1f <0f> b7 c0 48 0f a3 05 4d 1b 13 14 73 15 48 8d 04 80 48 8d 04 80 48
RSP: 0018:ffffc90000007c30 EFLAGS: 00000002
RAX: 00000000000001bf RBX: ffff88802a8e0b18 RCX: 00000000fffffffe
RDX: 0000000000000000 RSI: ffff88802a8e0b18 RDI: ffff88802a8e0af0
RBP: ffff88802a8e0af0 R08: 0000000000080000 R09: 0000000000000001
R10: 0000000000000001 R11: 0000000000000000 R12: 0000000000000f34
R13: 0000000000000001 R14: ffff88802a8e0000 R15: 0000000000000000
FS:  0000000000000000(0000) GS:ffff8881249df000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000200000000200 CR3: 0000000070fc8000 CR4: 00000000003526f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <IRQ>
 __lock_acquire+0x974/0x1ba0 kernel/locking/lockdep.c:5231
 lock_acquire kernel/locking/lockdep.c:5866 [inline]
 lock_acquire+0x179/0x350 kernel/locking/lockdep.c:5823
 __raw_spin_lock include/linux/spinlock_api_smp.h:133 [inline]
 _raw_spin_lock+0x2e/0x40 kernel/locking/spinlock.c:154
 spin_lock include/linux/spinlock.h:351 [inline]
 advance_sched+0xd9/0xc80 net/sched/sch_taprio.c:924
 __run_hrtimer kernel/time/hrtimer.c:1761 [inline]
 __hrtimer_run_queues+0x1ff/0xad0 kernel/time/hrtimer.c:1825
 hrtimer_interrupt+0x397/0x8e0 kernel/time/hrtimer.c:1887
 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1038 [inline]
 __sysvec_apic_timer_interrupt+0x108/0x3f0 arch/x86/kernel/apic/apic.c:1055
 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1049 [inline]
 sysvec_apic_timer_interrupt+0x9f/0xc0 arch/x86/kernel/apic/apic.c:1049
 </IRQ>
 <TASK>
 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702
RIP: 0010:__rcu_read_unlock+0xeb/0x580 kernel/rcu/tree_plugin.h:441
Code: cc 01 00 00 8b 85 48 04 00 00 85 c0 75 57 65 48 8b 1d 51 64 02 12 48 8d bb 44 04 00 00 48 b8 00 00 00 00 00 fc ff df 48 89 fa <48> c1 ea 03 0f b6 14 02 48 89 f8 83 e0 07 83 c0 03 38 d0 7c 08 84
RSP: 0018:ffffc90011b3f200 EFLAGS: 00000246
RAX: dffffc0000000000 RBX: ffff88802a8e0000 RCX: ffffc90011b3f1f4
RDX: ffff88802a8e0444 RSI: ffffffff8dbbbc37 RDI: ffff88802a8e0444
RBP: ffff88802a8e0000 R08: 0000000000000001 R09: 0000000000000000
R10: 0000000000000001 R11: 00000000000113aa R12: ffff88802a8e0000
R13: ffffc90011b3f2a0 R14: ffffc90011b3f5b0 R15: ffffc90011b3f2d4
 rcu_read_unlock include/linux/rcupdate.h:873 [inline]
 class_rcu_destructor include/linux/rcupdate.h:1155 [inline]
 unwind_next_frame+0x3fe/0x20a0 arch/x86/kernel/unwind_orc.c:479
 arch_stack_walk+0x94/0x100 arch/x86/kernel/stacktrace.c:25
 stack_trace_save+0x8e/0xc0 kernel/stacktrace.c:122
 save_stack+0x160/0x1f0 mm/page_owner.c:156
 __reset_page_owner+0x84/0x1a0 mm/page_owner.c:308
 reset_page_owner include/linux/page_owner.h:25 [inline]
 free_pages_prepare mm/page_alloc.c:1262 [inline]
 free_unref_folios+0x999/0x1630 mm/page_alloc.c:2782
 folios_put_refs+0x56f/0x740 mm/swap.c:992
 free_pages_and_swap_cache+0x245/0x4a0 mm/swap_state.c:267
 __tlb_batch_free_encoded_pages+0xf9/0x290 mm/mmu_gather.c:136
 tlb_batch_pages_flush mm/mmu_gather.c:149 [inline]
 tlb_flush_mmu_free mm/mmu_gather.c:397 [inline]
 tlb_flush_mmu mm/mmu_gather.c:404 [inline]
 tlb_finish_mmu+0x168/0x7b0 mm/mmu_gather.c:496
 exit_mmap+0x403/0xb90 mm/mmap.c:1297
 __mmput+0x12a/0x410 kernel/fork.c:1379
 mmput+0x62/0x70 kernel/fork.c:1401
 exit_mm kernel/exit.c:589 [inline]
 do_exit+0x9d1/0x2c30 kernel/exit.c:940
 do_group_exit+0xd3/0x2a0 kernel/exit.c:1102
 get_signal+0x2673/0x26d0 kernel/signal.c:3034
 arch_do_signal_or_restart+0x8f/0x7d0 arch/x86/kernel/signal.c:337
 exit_to_user_mode_loop kernel/entry/common.c:111 [inline]
 exit_to_user_mode_prepare include/linux/entry-common.h:329 [inline]
 __syscall_exit_to_user_mode_work kernel/entry/common.c:207 [inline]
 syscall_exit_to_user_mode+0x150/0x2a0 kernel/entry/common.c:218
 do_syscall_64+0xda/0x260 arch/x86/entry/syscall_64.c:100
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fe3e178e969
Code: Unable to access opcode bytes at 0x7fe3e178e93f.
RSP: 002b:00007fe3e267a0e8 EFLAGS: 00000246 ORIG_RAX: 00000000000000ca
RAX: fffffffffffffe00 RBX: 00007fe3e19b5fa8 RCX: 00007fe3e178e969
RDX: 0000000000000000 RSI: 0000000000000080 RDI: 00007fe3e19b5fa8
RBP: 00007fe3e19b5fa0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00007fe3e19b5fac
R13: 0000000000000000 R14: 00007fff67f2eb30 R15: 00007fff67f2ec18
 </TASK>
rcu: rcu_preempt kthread timer wakeup didn't happen for 10504 jiffies! g125873 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x402
rcu: 	Possible timer handling issue on cpu=0 timer-softirq=47085
rcu: rcu_preempt kthread starved for 10505 jiffies! g125873 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x402 ->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:I stack:28728 pid:16    tgid:16    ppid:2      task_flags:0x208040 flags:0x00004000
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5382 [inline]
 __schedule+0x116f/0x5de0 kernel/sched/core.c:6767
 __schedule_loop kernel/sched/core.c:6845 [inline]
 schedule+0xe7/0x3a0 kernel/sched/core.c:6860
 schedule_timeout+0x123/0x290 kernel/time/sleep_timeout.c:99
 rcu_gp_fqs_loop+0x1ea/0xb00 kernel/rcu/tree.c:2046
 rcu_gp_kthread+0x270/0x380 kernel/rcu/tree.c:2248
 kthread+0x3c2/0x780 kernel/kthread.c:464
 ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:153
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
 </TASK>