rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 	Tasks blocked on level-0 rcu_node (CPUs 0-1): P8726/1:b..l
	(detected by 1, t=10502 jiffies, g=28373, q=59)
task:syz-executor    state:R  running task     stack:28096 pid: 8726 ppid:  4177 flags:0x00004000
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5027 [inline]
 __schedule+0x12c4/0x45b0 kernel/sched/core.c:6373
 preempt_schedule_common+0x83/0xd0 kernel/sched/core.c:6549
 preempt_schedule+0xd9/0xe0 kernel/sched/core.c:6574
 preempt_schedule_thunk+0x16/0x18 arch/x86/entry/thunk_64.S:34
 __raw_spin_unlock include/linux/spinlock_api_smp.h:152 [inline]
 _raw_spin_unlock+0x36/0x40 kernel/locking/spinlock.c:186
 spin_unlock include/linux/spinlock.h:403 [inline]
 filemap_map_pages+0x122d/0x15c0 mm/filemap.c:3353
 do_fault_around mm/memory.c:4241 [inline]
 do_read_fault mm/memory.c:4256 [inline]
 do_fault mm/memory.c:4390 [inline]
 handle_pte_fault mm/memory.c:4648 [inline]
 __handle_mm_fault mm/memory.c:4783 [inline]
 handle_mm_fault+0x341b/0x5960 mm/memory.c:4881
 do_user_addr_fault arch/x86/mm/fault.c:1357 [inline]
 handle_page_fault arch/x86/mm/fault.c:1445 [inline]
 exc_page_fault+0x271/0x700 arch/x86/mm/fault.c:1501
 asm_exc_page_fault+0x22/0x30 arch/x86/include/asm/idtentry.h:606
RIP: 0033:0x7f267f44da30
RSP: 002b:00007fff8029cb08 EFLAGS: 00010216
RAX: 0000000000000020 RBX: 00007fff8029d070 RCX: 0000000000000000
RDX: 000000000000000a RSI: 00007fff8029d018 RDI: 0000000000000003
RBP: 0000000000000016 R08: 0000000000000000 R09: 0000000000000000
R10: 00000000ffffffff R11: 0000000000000001 R12: 0000000000000075
R13: 00007fff8029d1f0 R14: 00007fff8029d018 R15: 0000000000000003
 </TASK>
rcu: rcu_preempt kthread starved for 10505 jiffies! g28373 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x0 ->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:R  running task     stack:27064 pid:   15 ppid:     2 flags:0x00004000
Call Trace:
 <TASK>
 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
 </TASK>
rcu: Stack dump where RCU GP kthread last ran:
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0 skipped: idling at native_safe_halt arch/x86/include/asm/irqflags.h:51 [inline]
NMI backtrace for cpu 0 skipped: idling at arch_safe_halt arch/x86/include/asm/irqflags.h:89 [inline]
NMI backtrace for cpu 0 skipped: idling at acpi_safe_halt drivers/acpi/processor_idle.c:108 [inline]
NMI backtrace for cpu 0 skipped: idling at acpi_idle_do_entry+0x10f/0x340 drivers/acpi/processor_idle.c:562