rcu: INFO: rcu_preempt detected stalls on CPUs/tasks: rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P9193/1:b..l (detected by 1, t=10502 jiffies, g=50837, q=148 ncpus=2) task:syz.1.1438 state:R running task stack:23928 pid:9193 ppid:5232 flags:0x00004000 Call Trace: context_switch kernel/sched/core.c:5244 [inline] __schedule+0x143f/0x4570 kernel/sched/core.c:6561 preempt_schedule_irq+0xf7/0x1c0 kernel/sched/core.c:6873 irqentry_exit+0x53/0x80 kernel/entry/common.c:439 asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:653 RIP: 0010:lock_is_held_type+0x137/0x180 Code: 75 40 48 c7 04 24 00 00 00 00 9c 8f 04 24 f7 04 24 00 02 00 00 75 46 41 f7 c4 00 02 00 00 74 01 fb 65 48 8b 04 25 28 00 00 00 <48> 3b 44 24 08 75 3c 89 e8 48 83 c4 10 5b 41 5c 41 5d 41 5e 41 5f RSP: 0018:ffffc9000511f5a0 EFLAGS: 00000206 RAX: 7d2bd68cb8668800 RBX: 0000000000000001 RCX: 0000000080000000 RDX: ffffc9000a95a000 RSI: ffffffff8aec13c0 RDI: ffffffff8b3d48a0 RBP: 0000000000000001 R08: ffffffff81ecc94a R09: fffffbfff2093845 R10: 0000000000000000 R11: dffffc0000000001 R12: 0000000000000246 R13: ffff88805d908000 R14: 00000000ffffffff R15: ffffffff8d12ad40 lookup_page_ext mm/page_ext.c:277 [inline] page_ext_get+0x18e/0x2a0 mm/page_ext.c:158 __page_table_check_zero+0x139/0x4b0 mm/page_table_check.c:146 page_table_check_free include/linux/page_table_check.h:46 [inline] free_pages_prepare mm/page_alloc.c:1445 [inline] free_pcp_prepare mm/page_alloc.c:1494 [inline] free_unref_page_prepare+0xf73/0x1120 mm/page_alloc.c:3362 free_unref_page_list+0x663/0x900 mm/page_alloc.c:3503 release_pages+0x2836/0x2b40 mm/swap.c:1055 tlb_batch_pages_flush mm/mmu_gather.c:59 [inline] tlb_flush_mmu_free mm/mmu_gather.c:254 [inline] tlb_flush_mmu+0xfc/0x210 mm/mmu_gather.c:261 tlb_finish_mmu+0xce/0x1f0 mm/mmu_gather.c:361 unmap_region+0x29f/0x2f0 mm/mmap.c:2332 do_mas_align_munmap+0xec8/0x15f0 mm/mmap.c:2582 do_mas_munmap+0x246/0x2b0 mm/mmap.c:2640 __vm_munmap+0x268/0x370 mm/mmap.c:2917 __do_sys_munmap mm/mmap.c:2942 [inline] __se_sys_munmap mm/mmap.c:2939 [inline] __x64_sys_munmap+0x5c/0x70 mm/mmap.c:2939 do_syscall_x64 arch/x86/entry/common.c:51 [inline] do_syscall_64+0x3b/0xb0 arch/x86/entry/common.c:81 entry_SYSCALL_64_after_hwframe+0x68/0xd2 RIP: 0033:0x7f3574f75fa7 RSP: 002b:00007f3575d0ae28 EFLAGS: 00000246 ORIG_RAX: 000000000000000b RAX: ffffffffffffffda RBX: 0000000001000000 RCX: 00007f3574f75fa7 RDX: 0000000000000000 RSI: 0000000008400000 RDI: 00007f356b3f7000 RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000009687 R10: 00000000200259c2 R11: 0000000000000246 R12: 0000000000000003 R13: 00007f3575d0af00 R14: 00007f3575d0aec0 R15: 00007f356b3f7000 rcu: rcu_preempt kthread timer wakeup didn't happen for 9949 jiffies! g50837 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x402 rcu: Possible timer handling issue on cpu=1 timer-softirq=25177 rcu: rcu_preempt kthread starved for 9950 jiffies! g50837 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x402 ->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:25528 pid:16 ppid:2 flags:0x00004000 Call Trace: context_switch kernel/sched/core.c:5244 [inline] __schedule+0x143f/0x4570 kernel/sched/core.c:6561 schedule+0xbf/0x180 kernel/sched/core.c:6637 schedule_timeout+0x1b9/0x300 kernel/time/timer.c:1965 rcu_gp_fqs_loop+0x2d2/0x1150 kernel/rcu/tree.c:1706 rcu_gp_kthread+0xa3/0x3b0 kernel/rcu/tree.c:1905 kthread+0x28d/0x320 kernel/kthread.c:376 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295 rcu: Stack dump where RCU GP kthread last ran: CPU: 1 PID: 0 Comm: swapper/1 Not tainted 6.1.100-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 06/27/2024 RIP: 0010:native_save_fl arch/x86/include/asm/irqflags.h:22 [inline] RIP: 0010:arch_local_save_flags arch/x86/include/asm/irqflags.h:70 [inline] RIP: 0010:arch_irqs_disabled arch/x86/include/asm/irqflags.h:130 [inline] RIP: 0010:acpi_safe_halt drivers/acpi/processor_idle.c:112 [inline] RIP: 0010:acpi_idle_do_entry+0x10f/0x340 drivers/acpi/processor_idle.c:567 Code: 0b f5 f6 48 83 e3 08 0f 85 0b 01 00 00 4c 8d 74 24 20 e8 f4 c9 fb f6 0f 1f 44 00 00 e8 4a 07 f5 f6 0f 00 2d 63 d5 b1 00 fb f4 <4c> 89 f3 48 c1 eb 03 42 80 3c 3b 00 74 08 4c 89 f7 e8 3b 8f 4c f7 RSP: 0018:ffffc90000177b80 EFLAGS: 000002d3 RAX: ffffffff8a959336 RBX: 0000000000000000 RCX: ffff888012739dc0 RDX: 0000000000000000 RSI: ffffffff8aec0240 RDI: ffffffff8b3d48a0 RBP: ffffc90000177c10 R08: ffffffff8a959318 R09: ffffed10024e73b9 R10: 0000000000000000 R11: dffffc0000000001 R12: 1ffff9200002ef70 R13: ffff888143e8c004 R14: ffffc90000177ba0 R15: dffffc0000000000 FS: 0000000000000000(0000) GS:ffff8880b9900000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f737d2236c0 CR3: 00000000220ba000 CR4: 00000000003506e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: acpi_idle_enter+0x352/0x4f0 drivers/acpi/processor_idle.c:704 cpuidle_enter_state+0x516/0xf80 drivers/cpuidle/cpuidle.c:239 cpuidle_enter+0x59/0x90 drivers/cpuidle/cpuidle.c:356 call_cpuidle kernel/sched/idle.c:155 [inline] cpuidle_idle_call kernel/sched/idle.c:236 [inline] do_idle+0x3ce/0x680 kernel/sched/idle.c:303 cpu_startup_entry+0x3d/0x60 kernel/sched/idle.c:401 start_secondary+0xe4/0xf0 arch/x86/kernel/smpboot.c:281 secondary_startup_64_no_verify+0xcf/0xdb