How to root Xperia Neo L

     Go to settings > Security > Mark  "Unknown sources"

     Settings > Developer options > Mark USB debugging

1. Flash this Kernel ( to learn flashing , see above )
2. Flashtool may show error after flashing kernel, no worries. Even your build number and android version won't change. Everything would remain same so please don't visit phone's settings to check anything
3. After flashing restart your device, It may not start completely, may remain at Sony logo or with blank/black screen.Whatever the status is, just restart your device and proceed with the rooting >Download this rooting toolkit > 1 / 2 / 3 / 4 and extract it. Now connect your phone to PC and wait for a minute. Run the rooting toolkit and waait till it finishes with the rooting process.
4. Flash 4.1.B.0.626 Kenel if you are on 4.1.B.0.626 firmware. Flash 4.1.B.0.631 kernel if you're on 4.1.B.0.631