[gentoo-user] what does this mean:rcu_sched detected stalls on CPUs/tasks

[东方巽雷]

My pc have a random boot problem.I can hardly make it clear when will occur.
The kern.log shows  INFO: rcu_sched detected stalls on CPUs/tasks: { 0}
(detected by 1, t=10002 jiffies, g=18446744073709551325,
c=18446744073709551324, q=13).
When this happen on boot,the kernel seems hung and will take about one or
two minuts,then continue booting as normal.Does anyone know the reason?