yum提示Another app is currently holding the yum lock; waiting for it to exit…
Loaded plugins: fastestmirror, refresh-packagekit, security
Existing lock /var/run/yum.pid: another copy is running as pid 25960.
Another app is currently holding the yum lock; waiting for it to exit...可以通过强制关掉yum进程：
rm -f /var/run/yum.pid