rcu: INFO: rcu_preempt detected stalls on CPUs/tasks: rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P3668/2:b..l (detected by 1, t=10502 jiffies, g=4989, q=192) task:syz.2.8 state:R running task stack:24984 pid: 3668 ppid: 3568 flags:0x00004000 Call Trace: context_switch kernel/sched/core.c:5027 [inline] __schedule+0x12c4/0x45b0 kernel/sched/core.c:6373 preempt_schedule_irq+0xf7/0x1c0 kernel/sched/core.c:6777 irqentry_exit+0x53/0x80 kernel/entry/common.c:432 asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:638 RIP: 0010:__preempt_count_add kernel/rcu/tree.c:1119 [inline] RIP: 0010:rcu_is_watching+0x4/0xa0 kernel/rcu/tree.c:1122 Code: 5d 41 5e 41 5f 5d c3 e8 ba 34 c8 08 41 f7 c4 00 02 00 00 75 b4 eb b3 e8 9a 34 c8 08 66 2e 0f 1f 84 00 00 00 00 00 41 57 41 56 <53> 65 ff 05 ec 56 97 7e e8 3f 48 c8 08 89 c3 83 f8 08 73 72 49 bf RSP: 0018:ffffc900031f7680 EFLAGS: 00000202 RAX: 0000000000000001 RBX: ffff88807722c010 RCX: ffff8880220a0000 RDX: dffffc0000000000 RSI: ffffffff8a8b3cc0 RDI: ffffffff8ad8f7c0 RBP: ffffea00017aae80 R08: dffffc0000000000 R09: fffffbfff1f8e219 R10: 0000000000000000 R11: dffffc0000000001 R12: dffffc0000000000 R13: 1ffff1100f58f0ba R14: ffff88807ac785d0 R15: ffff88807722c000 rcu_read_lock include/linux/rcupdate.h:740 [inline] percpu_ref_tryget_many include/linux/percpu-refcount.h:241 [inline] percpu_ref_tryget+0x1e/0x140 include/linux/percpu-refcount.h:266 css_tryget include/linux/cgroup.h:355 [inline] get_mem_cgroup_from_mm+0xd9/0x260 mm/memcontrol.c:991 __mem_cgroup_charge+0x12/0x80 mm/memcontrol.c:6777 mem_cgroup_charge include/linux/memcontrol.h:700 [inline] shmem_add_to_page_cache+0xc22/0x17c0 mm/shmem.c:718 shmem_getpage_gfp+0x1aa1/0x3190 mm/shmem.c:1940 shmem_getpage mm/shmem.c:151 [inline] shmem_write_begin+0xce/0x1a0 mm/shmem.c:2477 generic_perform_write+0x2bf/0x5b0 mm/filemap.c:3785 __generic_file_write_iter+0x243/0x4f0 mm/filemap.c:3912 generic_file_write_iter+0xa7/0x1b0 mm/filemap.c:3944 call_write_iter include/linux/fs.h:2172 [inline] new_sync_write fs/read_write.c:507 [inline] vfs_write+0xacd/0xe50 fs/read_write.c:594 ksys_write+0x1a2/0x2c0 fs/read_write.c:647 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x3b/0xb0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x66/0xd0 RIP: 0033:0x7f6bd0565e79 RSP: 002b:00007f6bce9e2038 EFLAGS: 00000246 ORIG_RAX: 0000000000000001 RAX: ffffffffffffffda RBX: 00007f6bd0701f80 RCX: 00007f6bd0565e79 RDX: 00000000ffffff6a RSI: 0000000020000000 RDI: 0000000000000004 RBP: 00007f6bd05d393e R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000000 R14: 00007f6bd0701f80 R15: 00007ffe58bdeee8 rcu: rcu_preempt kthread timer wakeup didn't happen for 10307 jiffies! g4989 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x402 rcu: Possible timer handling issue on cpu=1 timer-softirq=1749 rcu: rcu_preempt kthread starved for 10308 jiffies! g4989 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:26232 pid: 15 ppid: 2 flags:0x00004000 Call Trace: context_switch kernel/sched/core.c:5027 [inline] __schedule+0x12c4/0x45b0 kernel/sched/core.c:6373 schedule+0x11b/0x1f0 kernel/sched/core.c:6456 schedule_timeout+0x1b9/0x300 kernel/time/timer.c:1914 rcu_gp_fqs_loop+0x2bf/0x1080 kernel/rcu/tree.c:1972 rcu_gp_kthread+0xa4/0x360 kernel/rcu/tree.c:2145 kthread+0x3f6/0x4f0 kernel/kthread.c:334 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:287 rcu: Stack dump where RCU GP kthread last ran: NMI backtrace for cpu 1 CPU: 1 PID: 0 Comm: swapper/1 Not tainted 5.15.165-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/06/2024 Call Trace: __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0x1e3/0x2d0 lib/dump_stack.c:106 nmi_cpu_backtrace+0x46a/0x4a0 lib/nmi_backtrace.c:111 nmi_trigger_cpumask_backtrace+0x181/0x2a0 lib/nmi_backtrace.c:62 trigger_single_cpu_backtrace include/linux/nmi.h:166 [inline] rcu_check_gp_kthread_starvation+0x1d2/0x240 kernel/rcu/tree_stall.h:487 print_other_cpu_stall+0x137a/0x14d0 kernel/rcu/tree_stall.h:592 check_cpu_stall kernel/rcu/tree_stall.h:745 [inline] rcu_pending kernel/rcu/tree.c:3932 [inline] rcu_sched_clock_irq+0xa38/0x1150 kernel/rcu/tree.c:2619 update_process_times+0x196/0x200 kernel/time/timer.c:1818 tick_sched_handle kernel/time/tick-sched.c:254 [inline] tick_sched_timer+0x386/0x550 kernel/time/tick-sched.c:1473 __run_hrtimer kernel/time/hrtimer.c:1686 [inline] __hrtimer_run_queues+0x55b/0xcf0 kernel/time/hrtimer.c:1750 hrtimer_interrupt+0x392/0x980 kernel/time/hrtimer.c:1812 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1085 [inline] __sysvec_apic_timer_interrupt+0x139/0x470 arch/x86/kernel/apic/apic.c:1102 sysvec_apic_timer_interrupt+0x8c/0xb0 arch/x86/kernel/apic/apic.c:1096 asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:638 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:132 [inline] RIP: 0010:acpi_safe_halt drivers/acpi/processor_idle.c:109 [inline] RIP: 0010:acpi_idle_do_entry+0x10f/0x340 drivers/acpi/processor_idle.c:562 Code: 8a 43 f7 48 83 e3 08 0f 85 0a 01 00 00 4c 8d 74 24 20 e8 24 07 4a f7 0f 1f 44 00 00 e8 8a 86 43 f7 0f 00 2d c3 50 a6 00 fb f4 <4c> 89 f3 48 c1 eb 03 42 80 3c 3b 00 74 08 4c 89 f7 e8 bb 4f 8d f7 RSP: 0018:ffffc90000d67b00 EFLAGS: 000002d3 RAX: ffffffff8a3cdb16 RBX: 0000000000000000 RCX: ffff888012a18000 RDX: 0000000000000000 RSI: ffffffff8a8b2a20 RDI: ffffffff8ad8f7c0 RBP: ffffc90000d67b90 R08: ffffffff8186e260 R09: ffffed1002543001 R10: 0000000000000000 R11: dffffc0000000001 R12: 1ffff920001acf60 R13: ffff888145f07804 R14: ffffc90000d67b20 R15: dffffc0000000000 acpi_idle_enter+0x352/0x4f0 drivers/acpi/processor_idle.c:697 cpuidle_enter_state+0x521/0xef0 drivers/cpuidle/cpuidle.c:237 cpuidle_enter+0x59/0x90 drivers/cpuidle/cpuidle.c:351 call_cpuidle kernel/sched/idle.c:158 [inline] cpuidle_idle_call kernel/sched/idle.c:239 [inline] do_idle+0x3e4/0x670 kernel/sched/idle.c:306 cpu_startup_entry+0x14/0x20 kernel/sched/idle.c:403 start_secondary+0x371/0x500 arch/x86/kernel/smpboot.c:281 secondary_startup_64_no_verify+0xb1/0xbb