rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 	Tasks blocked on level-0 rcu_node (CPUs 0-1): P3027/2:b..l
	(detected by 1, t=10502 jiffies, g=11961, q=414)
task:udevd           state:R  running task     stack:23168 pid: 3027 ppid:     1 flags:0x00004002
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5030 [inline]
 __schedule+0x12c4/0x45b0 kernel/sched/core.c:6376
 preempt_schedule_irq+0xf7/0x1c0 kernel/sched/core.c:6780
 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:rht_key_hashfn include/linux/rhashtable.h:159 [inline]
RIP: 0010:__rhashtable_lookup include/linux/rhashtable.h:596 [inline]
RIP: 0010:rhashtable_lookup include/linux/rhashtable.h:638 [inline]
RIP: 0010:rhashtable_lookup_fast include/linux/rhashtable.h:664 [inline]
RIP: 0010:__netlink_lookup+0x149/0x680 net/netlink/af_netlink.c:516
Code: 89 44 24 08 48 8b 6c 24 10 48 c1 ed 20 4c 89 e2 4c 89 7c 24 28 48 89 6c 24 20 48 8d 7a 08 48 89 f8 48 c1 e8 03 42 0f b6 04 30 <84> c0 48 89 14 24 0f 85 c8 03 00 00 8b 42 08 44 8d a4 18 fb be ad
RSP: 0018:ffffc90002327768 EFLAGS: 00000a02
RAX: 0000000000000000 RBX: 00000000f65c6658 RCX: ffff88807d5f3b80
RDX: ffff88801fa71000 RSI: 0000000000000001 RDI: ffff88801fa71008
RBP: 00000000ffffffff R08: ffffffff8887b68d R09: fffffbfff1f8e019
R10: 0000000000000000 R11: dffffc0000000001 R12: ffff88801fa71000
R13: dffffc0000000000 R14: dffffc0000000000 R15: ffff8881447d98d8
 netlink_lookup+0xb5/0x1d0 net/netlink/af_netlink.c:536
 netlink_getsockbyportid net/netlink/af_netlink.c:1160 [inline]
 netlink_unicast+0x1a1/0x980 net/netlink/af_netlink.c:1346
 netlink_sendmsg+0xa30/0xd60 net/netlink/af_netlink.c:1920
 sock_sendmsg_nosec net/socket.c:704 [inline]
 __sock_sendmsg net/socket.c:716 [inline]
 ____sys_sendmsg+0x59e/0x8f0 net/socket.c:2431
 ___sys_sendmsg+0x252/0x2e0 net/socket.c:2485
 __sys_sendmsg net/socket.c:2514 [inline]
 __do_sys_sendmsg net/socket.c:2523 [inline]
 __se_sys_sendmsg+0x19a/0x260 net/socket.c:2521
 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: 0033:0x7f1f741faa4b
RSP: 002b:00007ffd5c168518 EFLAGS: 00000246 ORIG_RAX: 000000000000002e
RAX: ffffffffffffffda RBX: 0000558164118df0 RCX: 00007f1f741faa4b
RDX: 0000000000000000 RSI: 00007ffd5c168528 RDI: 0000000000000004
RBP: 000055816413f640 R08: 0000000000000001 R09: 0000000000000000
R10: 000000000000010f R11: 0000000000000246 R12: 0000000000000000
R13: 00000000000000b4 R14: 0000000000000000 R15: 0000000000000000
 </TASK>
rcu: rcu_preempt kthread starved for 9978 jiffies! g11961 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:27256 pid:   15 ppid:     2 flags:0x00004000
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5030 [inline]
 __schedule+0x12c4/0x45b0 kernel/sched/core.c:6376
 schedule+0x11b/0x1f0 kernel/sched/core.c:6459
 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