使用ThinkPad跑ubuntu，安装了unity，以前用xfce可以在设置里面修改小红点的速度，现在发现unity不能直接修改，就用xinput定位到自己的硬件，昨天修改了accel speed，确实可以用，但是今天再开机就有回到很快的速度了，应该是要修改accel speed default，我尝试修改这个值，出现了报错。
root@linux:/home/linux# xinput set-prop 12 313 -0.5
X Error of failed request: BadAccess (attempt to access private resource denied)
Major opcode of failed request: 131 (XInputExtension)
Minor opcode of failed request: 57 ()
Serial number of failed request: 19
Current serial number in output stream: 20
在普通环境和root环境都试过了，都会报错。请问各位大神该怎么办？
root@linux:/home/linux# xinput set-prop 12 313 -0.5
X Error of failed request: BadAccess (attempt to access private resource denied)
Major opcode of failed request: 131 (XInputExtension)
Minor opcode of failed request: 57 ()
Serial number of failed request: 19
Current serial number in output stream: 20
在普通环境和root环境都试过了，都会报错。请问各位大神该怎么办？
