rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 	Tasks blocked on level-0 rcu_node (CPUs 0-1): P6471/1:b..l
	(detected by 1, t=10502 jiffies, g=26173, q=13)
task:syz.4.466       state:R  running task     stack:    0 pid: 6471 ppid:  5843 flags:0x00000008
Call trace:
 __switch_to+0x308/0x5e8 arch/arm64/kernel/process.c:518
 context_switch kernel/sched/core.c:5027 [inline]
 __schedule+0xf10/0x1e48 kernel/sched/core.c:6373
 preempt_schedule_irq+0x90/0x274 kernel/sched/core.c:6777
 arm64_preempt_schedule_irq+0x174/0x2c4 arch/arm64/kernel/entry-common.c:260
 el1_interrupt+0x40/0x58 arch/arm64/kernel/entry-common.c:463
 el1h_64_irq_handler+0x18/0x24 arch/arm64/kernel/entry-common.c:470
 el1h_64_irq+0x78/0x7c arch/arm64/kernel/entry.S:522
 arch_local_irq_restore+0x8/0x10 arch/arm64/include/asm/irqflags.h:122
 lock_is_held include/linux/lockdep.h:287 [inline]
 task_css include/linux/cgroup.h:496 [inline]
 mem_cgroup_from_task+0x64/0x120 mm/memcontrol.c:935
 get_mem_cgroup_from_mm+0xd4/0x384 mm/memcontrol.c:988
 __mem_cgroup_charge+0x24/0xa8 mm/memcontrol.c:6797
 mem_cgroup_charge include/linux/memcontrol.h:700 [inline]
 shmem_add_to_page_cache+0x898/0x16a0 mm/shmem.c:718
 shmem_getpage_gfp+0x1398/0x20e4 mm/shmem.c:1940
 shmem_fault+0x194/0x560 mm/shmem.c:2118
 __do_fault+0x120/0x5d0 mm/memory.c:3898
 do_read_fault mm/memory.c:4234 [inline]
 do_fault mm/memory.c:4362 [inline]
 handle_pte_fault mm/memory.c:4620 [inline]
 __handle_mm_fault mm/memory.c:4755 [inline]
 handle_mm_fault+0x21e8/0x33a8 mm/memory.c:4853
 faultin_page mm/gup.c:976 [inline]
 __get_user_pages+0x39c/0x92c mm/gup.c:1197
 populate_vma_page_range+0x200/0x290 mm/gup.c:1529
 __mm_populate+0x278/0x41c mm/gup.c:1638
 mm_populate include/linux/mm.h:2632 [inline]
 vm_mmap_pgoff+0x1fc/0x2b4 mm/util.c:556
 ksys_mmap_pgoff+0x11c/0x668 mm/mmap.c:1624
 __do_sys_mmap arch/arm64/kernel/sys.c:28 [inline]
 __se_sys_mmap arch/arm64/kernel/sys.c:21 [inline]
 __arm64_sys_mmap+0xf8/0x110 arch/arm64/kernel/sys.c:21
 __invoke_syscall arch/arm64/kernel/syscall.c:38 [inline]
 invoke_syscall+0x98/0x2b8 arch/arm64/kernel/syscall.c:52
 el0_svc_common+0x138/0x258 arch/arm64/kernel/syscall.c:142
 do_el0_svc+0x58/0x14c arch/arm64/kernel/syscall.c:181
 el0_svc+0x7c/0x1f0 arch/arm64/kernel/entry-common.c:608
 el0t_64_sync_handler+0x84/0xe4 arch/arm64/kernel/entry-common.c:626
 el0t_64_sync+0x1a0/0x1a4 arch/arm64/kernel/entry.S:584
rcu: rcu_preempt kthread starved for 10506 jiffies! g26173 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:    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:5027 [inline]
 __schedule+0xf10/0x1e48 kernel/sched/core.c:6373
 schedule+0x11c/0x1c8 kernel/sched/core.c:6456
 schedule_timeout+0x1d8/0x344 kernel/time/timer.c:1914
 rcu_gp_fqs_loop+0x26c/0x13d4 kernel/rcu/tree.c:1972
 rcu_gp_kthread+0xc4/0x2c4 kernel/rcu/tree.c:2145
 kthread+0x37c/0x45c kernel/kthread.c:334
 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.2.468       state:R  running task     stack:    0 pid: 6480 ppid:  6306 flags:0x00000001
Call trace:
 __switch_to+0x308/0x5e8 arch/arm64/kernel/process.c:518
 walk_stackframe+0x6c/0xa8 arch/arm64/kernel/stacktrace.c:148
 0xffff0000c66609e0