syzbot

rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 	Tasks blocked on level-0 rcu_node (CPUs 0-1): P5892/1:b..l P4015/1:b..l
	(detected by 0, t=10502 jiffies, g=11961, q=540)
task:syz-executor.4  state:R  running task     stack:    0 pid: 4015 ppid:  3997 flags:0x00000004
Call trace:
 __switch_to+0x308/0x5e8 arch/arm64/kernel/process.c:518
 context_switch kernel/sched/core.c:5026 [inline]
 __schedule+0xf10/0x1e38 kernel/sched/core.c:6372
 preempt_schedule_irq+0x90/0x274 kernel/sched/core.c:6776
 arm64_preempt_schedule_irq+0x174/0x2c4 arch/arm64/kernel/entry-common.c:260
 el1_interrupt+0x40/0x58 arch/arm64/kernel/entry-common.c:451
 el1h_64_irq_handler+0x18/0x24 arch/arm64/kernel/entry-common.c:458
 el1h_64_irq+0x78/0x7c arch/arm64/kernel/entry.S:580
 lock_is_held_type+0x15c/0x1a8 kernel/locking/lockdep.c:5670
 lock_is_held include/linux/lockdep.h:287 [inline]
 task_css include/linux/cgroup.h:495 [inline]
 mem_cgroup_from_task+0x70/0x118 mm/memcontrol.c:935
 get_mem_cgroup_from_mm+0xd4/0x3dc mm/memcontrol.c:988
 __mem_cgroup_charge+0x24/0xa8 mm/memcontrol.c:6776
 mem_cgroup_charge include/linux/memcontrol.h:700 [inline]
 wp_page_copy+0x244/0x132c mm/memory.c:3048
 do_wp_page+0x6c4/0x9c4
 handle_pte_fault mm/memory.c:4639 [inline]
 __handle_mm_fault mm/memory.c:4756 [inline]
 handle_mm_fault+0x1ce4/0x33c4 mm/memory.c:4854
 __do_page_fault arch/arm64/mm/fault.c:505 [inline]
 do_page_fault+0x700/0xb60 arch/arm64/mm/fault.c:605
 do_mem_abort+0x70/0x1d8 arch/arm64/mm/fault.c:819
 el0_da+0x94/0x20c arch/arm64/kernel/entry-common.c:482
 el0t_64_sync_handler+0xc0/0xe4 arch/arm64/kernel/entry-common.c:617
 el0t_64_sync+0x1a0/0x1a4 arch/arm64/kernel/entry.S:584
task:syz-executor.5  state:R  running task     stack:    0 pid: 5892 ppid:  4003 flags:0x00000004
Call trace:
 __switch_to+0x308/0x5e8 arch/arm64/kernel/process.c:518
 context_switch kernel/sched/core.c:5026 [inline]
 __schedule+0xf10/0x1e38 kernel/sched/core.c:6372
 preempt_schedule_irq+0x90/0x274 kernel/sched/core.c:6776
 arm64_preempt_schedule_irq+0x174/0x2c4 arch/arm64/kernel/entry-common.c:260
 el1_interrupt+0x40/0x58 arch/arm64/kernel/entry-common.c:451
 el1h_64_irq_handler+0x18/0x24 arch/arm64/kernel/entry-common.c:458
 el1h_64_irq+0x78/0x7c arch/arm64/kernel/entry.S:580
 arch_local_irq_restore arch/arm64/include/asm/irqflags.h:122 [inline]
 count_memcg_events include/linux/memcontrol.h:1058 [inline]
 count_memcg_event_mm+0x1d0/0x308 include/linux/memcontrol.h:1081
 handle_mm_fault+0x1c8/0x33c4 mm/memory.c:4834
 __do_page_fault arch/arm64/mm/fault.c:505 [inline]
 do_page_fault+0x700/0xb60 arch/arm64/mm/fault.c:605
 do_translation_fault+0xe8/0x138 arch/arm64/mm/fault.c:686
 do_mem_abort+0x70/0x1d8 arch/arm64/mm/fault.c:819
 el0_da+0x94/0x20c arch/arm64/kernel/entry-common.c:482
 el0t_64_sync_handler+0xc0/0xe4 arch/arm64/kernel/entry-common.c:617
 el0t_64_sync+0x1a0/0x1a4 arch/arm64/kernel/entry.S:584
rcu: rcu_preempt kthread starved for 9768 jiffies! g11961 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:    0 pid:   15 ppid:     2 flags:0x00000008
Call trace:
 __switch_to+0x308/0x5e8 arch/arm64/kernel/process.c:518
 context_switch kernel/sched/core.c:5026 [inline]
 __schedule+0xf10/0x1e38 kernel/sched/core.c:6372
 preempt_schedule_common+0x140/0x260 kernel/sched/core.c:6548
 preempt_schedule+0x64/0x84 kernel/sched/core.c:6573
 __raw_spin_unlock_irqrestore include/linux/spinlock_api_smp.h:161 [inline]
 _raw_spin_unlock_irqrestore+0x114/0x158 kernel/locking/spinlock.c:194
 prepare_to_swait_event+0x2a0/0x2ec kernel/sched/swait.c:120
 rcu_gp_fqs_loop+0x228/0x12cc kernel/rcu/tree.c:1959
 rcu_gp_kthread+0xc4/0x2c4 kernel/rcu/tree.c:2132
 kthread+0x37c/0x45c kernel/kthread.c:319
 ret_from_fork+0x10/0x20 arch/arm64/kernel/entry.S:870
rcu: Stack dump where RCU GP kthread last ran:
Task dump for CPU 0:
task:syz-executor.3  state:R  running task     stack:    0 pid: 5891 ppid:  4019 flags:0x00000001
Call trace:
 dump_backtrace+0x0/0x530 arch/arm64/kernel/stacktrace.c:152
 show_stack+0x2c/0x3c arch/arm64/kernel/stacktrace.c:216
 sched_show_task+0x43c/0x574 kernel/sched/core.c:8636
 dump_cpu_task+0x84/0xa8 kernel/sched/core.c:10908
 rcu_check_gp_kthread_starvation+0x1f0/0x254 kernel/rcu/tree_stall.h:482
 print_other_cpu_stall kernel/rcu/tree_stall.h:586 [inline]
 check_cpu_stall kernel/rcu/tree_stall.h:729 [inline]
 rcu_pending kernel/rcu/tree.c:3911 [inline]
 rcu_sched_clock_irq+0x43bc/0x4904 kernel/rcu/tree.c:2606
 update_process_times+0x1d4/0x270 kernel/time/timer.c:1788
 tick_sched_handle kernel/time/tick-sched.c:254 [inline]
 tick_sched_timer+0x340/0x4f8 kernel/time/tick-sched.c:1473
 __run_hrtimer kernel/time/hrtimer.c:1685 [inline]
 __hrtimer_run_queues+0x458/0xca4 kernel/time/hrtimer.c:1749
 hrtimer_interrupt+0x4e0/0xb64 kernel/time/hrtimer.c:1811
 timer_handler drivers/clocksource/arm_arch_timer.c:659 [inline]
 arch_timer_handler_virt+0x74/0x88 drivers/clocksource/arm_arch_timer.c:670
 handle_percpu_devid_irq+0x29c/0x7fc kernel/irq/chip.c:933
 generic_handle_irq_desc include/linux/irqdesc.h:158 [inline]
 handle_irq_desc kernel/irq/irqdesc.c:651 [inline]
 handle_domain_irq+0xec/0x178 kernel/irq/irqdesc.c:706
 gic_handle_irq+0x78/0x1c8 drivers/irqchip/irq-gic-v3.c:758
 call_on_irq_stack+0x24/0x4c arch/arm64/kernel/entry.S:899
 do_interrupt_handler+0x74/0x94 arch/arm64/kernel/entry-common.c:267
 el1_interrupt+0x30/0x58 arch/arm64/kernel/entry-common.c:442
 el1h_64_irq_handler+0x18/0x24 arch/arm64/kernel/entry-common.c:458
 el1h_64_irq+0x78/0x7c arch/arm64/kernel/entry.S:580
 arch_local_irq_enable arch/arm64/include/asm/irqflags.h:35 [inline]
 __raw_spin_unlock_irq include/linux/spinlock_api_smp.h:168 [inline]
 _raw_spin_unlock_irq+0xa4/0x134 kernel/locking/spinlock.c:202
 spin_unlock_irq include/linux/spinlock.h:413 [inline]
 get_signal+0x11b4/0x1550 kernel/signal.c:2892
 do_signal arch/arm64/kernel/signal.c:890 [inline]
 do_notify_resume+0x320/0x32b8 arch/arm64/kernel/signal.c:943
 prepare_exit_to_user_mode arch/arm64/kernel/entry-common.c:133 [inline]
 exit_to_user_mode arch/arm64/kernel/entry-common.c:138 [inline]
 el0_svc+0xfc/0x1f0 arch/arm64/kernel/entry-common.c:597
 el0t_64_sync_handler+0x84/0xe4 arch/arm64/kernel/entry-common.c:614
 el0t_64_sync+0x1a0/0x1a4 arch/arm64/kernel/entry.S:584