The server is always down while installing QAT driver

Hi Team,

I'm not sure whether I should ask questions here. This problem has been bothering me for a long time.
While I installing QAT driver, the server is always down after a certain step. I have to restart server through field engineer, and then I reinstall QAT driver, the problem won't happen again.
```
make[3]: Leaving directory `/usr/src/kernels/2.6.32-642.el6.x86_64'
make[2]: Leaving directory `/usr/local/src/ssl/qat1.7.l.4.4.0-00023/quickassist/qat'
Creating startup and kill scripts
Copying libqat_s.so to /usr/local/QAT_driver/lib
Copying libusdm_drv_s.so to /usr/local/QAT_driver/lib
Copying usdm module to system drivers
Creating udev rules
Creating module.dep file for QAT released kernel object
This will take a few moments
Starting QAT service
Stopping all devices.
Failed to stop device

Connection closed by foreign host.

Disconnected from remote host at 12:31:37.
```

OS: CentOS 6.8
kernel: 2.6.32-642.el6.x86_64
driver version: qat1.7.l.4.4.0-00023

Thanks in advance!