tutorial how to Root Your Xperia M2 Single & Dual
I just n00bs here, need to share my knowledge
4.3 JELLY BEAN
LOCKED BOOTLOADER
Using Towel Root (
Download) download & click Root, Your device will rebooted. After that download SuperSU in Play Store.
UNLOCK BOOTLOADER
Just Download The Recovery For Your Device (Single or Dual) and Download SuperSU.zip and flash the zip You get rooted fast!!
4.4 KITKAT
LOCKED BOOTLOADER
Not possible right now..
UNLOCK BOOTLOADER
1. Flash FTF 4.4 Kitkat
2. Flash CWM Kernel (Whatever it's for 4.3 or 4.4) You must get booted to CWM only
3. Download & Flash SuperSU.zip
4. Power Off & Flash Kernel 4.4 From FTF
5. You can find how to fix mount system
here
source