解决adb shell 找不到设备的问题
sudo adb shell
zhang@zhang-desktop:~$ adb shell
error: insufficient permissions for device

sudo adb device
zhang@zhang-desktop:~$ sudo adb devices
List of devices attached
????????????no permissions

解决：
zhang@zhang-desktop:~$ sudo adb kill-server
zhang@zhang-desktop:~$ sudo adb start-server
* daemon not running. starting it now *
* daemon started successfully *

ok了！
再看看：
zhang@zhang-desktop:~$ sudo adb devices
List of devices attached
170061c343c04457device

zhang@zhang-desktop:~$ sudo adb shell
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