rcu: INFO: rcu_preempt detected expedited stalls on CPUs/tasks: {
 } 2659 jiffies s: 269 root: 0x0/.
rcu: INFO: rcu_preempt detected expedited stalls on CPUs/tasks: {
 1-....
 } 2664 jiffies s: 273 root: 0x2/.
rcu: blocking rcu_node structures (internal RCU debug):