Maybe you ever find this image when you want to install new plugin or theme on your wordpress website :
One of the great features of WordPress is that it allows you to automatically install and upgrade plugins, automatic download it from wordpress.org download center.
As a normal practice, it is a good idea to not reboot to solve problems on a Linux system, because Linux systems are usually quite stable, and issues, if not directly kernel related (very rare except under kernel or module development and testing), then it is a service that can be restarted. After an update, that messed up, you have to make sure it put everything back the way it should be so it can boot back up if you are going to reboot. It may have hosed your /dev/ directory and stuff in it. It could be the result of a broken udev or makedev install.
