Crash工具笔记 （1）—— “current context”

成功启动crash会话后，会有一个task被指定为current context。因为有一些命令是context-sensitive，也即这些命令的运行会依赖于current context，所以知道当前的current context就很重要。

选择current context的标准：
a）coredump文件：

The task that was running when die() was called.
The task that was running when panic() was called.
The task that was running when an ALT-SYSRQ-c keyboard interrupt was received.
The task that was running when the character "c" was echoed to /proc/sysrq-trigger. 

b）当前运行的系统：

`crash`命令本身.

执行set命令显示当前current context：

crash> set
    PID: 2366
COMMAND: "crash"
   TASK: ffff88001ae60000  [THREAD_INFO: ffff88001c1f0000]
    CPU: 0
  STATE: TASK_RUNNING (ACTIVE)

也可利用set命令改变当前current context：

crash> set 1
    PID: 1
COMMAND: "systemd"
   TASK: ffff88001dfd8000  [THREAD_INFO: ffff88001dfe0000]
    CPU: 0
  STATE: TASK_INTERRUPTIBLE