You can now root gionee M5 now.

Recovery mode method has been the surest and safest method for rooting andriod 5.1 lollipop.
Those using Gionee M5 has not been able to get root access to their device since because no dedicated app could root it.All thanks to team hovatek this team has been a saviour indeed.

Read this:How to root camon c8 easily

• Download SuperSU.zip  move it to the rppt of your sdcard 
• You can get Twrp recovery mode here recovery ported by team hovatek
• To flash the recovery mode using spflash tools, follow this link here for detailed explanation.
• After flashing the recovery hold the power button and volume up your phone should be in recovery mode.
• Now click install zip then navigate to the root of your SD card and choose SuperSU.zip

Wait till process is done reboot your phone you should see SuperSU app installed.
Note:To check root accessibility, download root checker