rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 	Tasks blocked on level-0 rcu_node (CPUs 0-1): P4495/1:b..l
	(detected by 1, t=10502 jiffies, g=13713, q=222)
task:udevd           state:R  running task     stack:24216 pid: 4495 ppid:  3545 flags:0x00004002
Call Trace:
 <TASK>
 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:676
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:ffffc900032ff658 EFLAGS: 00000206
RAX: 99e0b53b17951200 RBX: 0000000000000002 RCX: 0000000080000000
RDX: dffffc0000000000 RSI: ffffffff8aab3d20 RDI: ffffffff8af9ed00
RBP: 0000000000000001 R08: dffffc0000000000 R09: fffffbfff2131021
R10: 0000000000000000 R11: dffffc0000000001 R12: 0000000000000246
R13: ffff8880782c5940 R14: 00000000ffffffff R15: ffffffff8cb1fc60
 task_css include/linux/cgroup.h:496 [inline]
 mem_cgroup_from_task+0x96/0x110 mm/memcontrol.c:935
 get_obj_cgroup_from_current+0x148/0x2f0 mm/memcontrol.c:2923
 memcg_slab_pre_alloc_hook mm/slab.h:283 [inline]
 slab_pre_alloc_hook+0x87/0xc0 mm/slab.h:497
 slab_alloc_node mm/slub.c:3134 [inline]
 slab_alloc mm/slub.c:3228 [inline]
 kmem_cache_alloc+0x3f/0x280 mm/slub.c:3233
 __d_alloc+0x2a/0x700 fs/dcache.c:1749
 d_alloc fs/dcache.c:1828 [inline]
 d_alloc_parallel+0xca/0x1390 fs/dcache.c:2582
 lookup_open fs/namei.c:3387 [inline]
 open_last_lookups fs/namei.c:3532 [inline]
 path_openat+0x96f/0x2f20 fs/namei.c:3739
 do_filp_open+0x21c/0x460 fs/namei.c:3769
 do_sys_openat2+0x13b/0x4f0 fs/open.c:1253
 do_sys_open fs/open.c:1269 [inline]
 __do_sys_openat fs/open.c:1285 [inline]
 __se_sys_openat fs/open.c:1280 [inline]
 __x64_sys_openat+0x243/0x290 fs/open.c:1280
 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: 0033:0x7fc344bbe9a4
RSP: 002b:00007fff13021cb0 EFLAGS: 00000246 ORIG_RAX: 0000000000000101
RAX: ffffffffffffffda RBX: 0000000000000004 RCX: 00007fc344bbe9a4
RDX: 0000000000080241 RSI: 00007fff130221f8 RDI: 00000000ffffff9c
RBP: 00007fff130221f8 R08: 0000000000000004 R09: 0000000000000001
R10: 00000000000001b6 R11: 0000000000000246 R12: 0000000000080241
R13: 000055d5dcf0a72e R14: 0000000000000001 R15: 000055d5f75d1910
 </TASK>
rcu: rcu_preempt kthread starved for 9665 jiffies! g13713 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