rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 	Tasks blocked on level-0 rcu_node (CPUs 0-1): P3547/1:b..l
	(detected by 0, t=10502 jiffies, g=13421, q=119)
task:udevd           state:R  running task     stack:23712 pid: 3547 ppid:     1 flags:0x00004002
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5030 [inline]
 __schedule+0x11b8/0x43b0 kernel/sched/core.c:6376
 preempt_schedule_common+0x82/0xd0 kernel/sched/core.c:6552
 preempt_schedule+0xa7/0xb0 kernel/sched/core.c:6577
 preempt_schedule_thunk+0x16/0x18 arch/x86/entry/thunk_64.S:34
 __raw_spin_unlock_irqrestore include/linux/spinlock_api_smp.h:161 [inline]
 _raw_spin_unlock_irqrestore+0xf6/0x100 kernel/locking/spinlock.c:194
 spin_unlock_irqrestore include/linux/spinlock.h:418 [inline]
 __wake_up_common_lock kernel/sched/wait.c:140 [inline]
 __wake_up_sync_key+0x11b/0x180 kernel/sched/wait.c:205
 sock_def_readable+0x136/0x250 net/core/sock.c:3093
 __netlink_sendskb net/netlink/af_netlink.c:1258 [inline]
 netlink_sendskb+0x97/0x130 net/netlink/af_netlink.c:1264
 netlink_sendmsg+0x8ab/0xbc0 net/netlink/af_netlink.c:1905
 sock_sendmsg_nosec net/socket.c:704 [inline]
 __sock_sendmsg net/socket.c:716 [inline]
 ____sys_sendmsg+0x5a2/0x8c0 net/socket.c:2436
 ___sys_sendmsg+0x1f0/0x260 net/socket.c:2490
 __sys_sendmsg net/socket.c:2519 [inline]
 __do_sys_sendmsg net/socket.c:2528 [inline]
 __se_sys_sendmsg+0x190/0x250 net/socket.c:2526
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x66/0xd0
RIP: 0033:0x7f02a9b4fa4b
RSP: 002b:00007fff6a6a40f8 EFLAGS: 00000246 ORIG_RAX: 000000000000002e
RAX: ffffffffffffffda RBX: 0000555a9e79c9e0 RCX: 00007f02a9b4fa4b
RDX: 0000000000000000 RSI: 00007fff6a6a4108 RDI: 0000000000000004
RBP: 0000555a9e7bfac0 R08: 0000000000000001 R09: 0000000000000000
R10: 000000000000010f R11: 0000000000000246 R12: 0000000000000000
R13: 00000000000000b3 R14: 0000000000000000 R15: 0000000000000000
 </TASK>
rcu: rcu_preempt kthread starved for 9946 jiffies! g13421 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x0 ->cpu=1
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:28032 pid:   15 ppid:     2 flags:0x00004000
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5030 [inline]
 __schedule+0x11b8/0x43b0 kernel/sched/core.c:6376
 schedule+0x11b/0x1e0 kernel/sched/core.c:6459
 schedule_timeout+0x15c/0x280 kernel/time/timer.c:1914
 rcu_gp_fqs_loop+0x29e/0x11b0 kernel/rcu/tree.c:1972
 rcu_gp_kthread+0x98/0x350 kernel/rcu/tree.c:2145
 kthread+0x436/0x520 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 0 to CPUs 1:
NMI backtrace for cpu 1 skipped: idling at native_safe_halt arch/x86/include/asm/irqflags.h:51 [inline]
NMI backtrace for cpu 1 skipped: idling at arch_safe_halt arch/x86/include/asm/irqflags.h:89 [inline]
NMI backtrace for cpu 1 skipped: idling at default_idle+0xb/0x10 arch/x86/kernel/process.c:722