1. Dec 15, 2013. Click flash button. Choose “Fastboot Mode“. Click “Reboot into fastboot mode (via ADB)“, and wait until it's done. Click on “Select kernel to flash“, choose the kernel file, and wait until it's done. Click on “Reboot device into system“. Check your phone whether it is restarting or not. That's all guys!
2. Kernel Installation: Kernels(boot.img) are the main base for any custom rom you install, kernels are installed using FASTBOOT feature of android ADB. You flash any custom rom make sure you've installed its related kernel (boot.img). 1: Download Flashtool and the kernel you want (for example the alliance kernel).

• Install Kernel Via Flashtool
• Install Thunderzap Kernel Using Flashtool

WARNING: IF YOUR PHONE DOESN'T START(BOOTLOOPING) YOU INSTALLED KERNEL NOT SUITABLE FOR YOUR CURRENT ROM. FIND DIFFERENT KERNEL AND REPEAT AGAIN. Method 2 using FLashtool. Open Flashtool 2. Connect your phone in Fastboot mode. On Flashtool choose the.

Matthieu HarléMatthieu Harlé

1 Answer

There are two ways, depending on your firmware version. They work on both locked & unlocked bootloader.

Requirements

• Having adb drivers installed (usually installed with Sony PC Companion)
• Having enabled Unknown Sources
• Having enabled USB Debugging
• PC Companion must not be running

(credits for DooMLoRD, guide from this thread)

1. Download this archive and extract it.
2. Connect your phone to your computer.
3. In the extracted folder, double click on the RUNME.bat file.
4. Follow the instructions (usually one key to tap).
5. Reboot your device if it doesn't do it itself.

Install Kernel Via Flashtool

(credits for DooMLoRD, guide from this thread) Eve tools planetary interaction production.

In these versions, Sony has patched the exploit, so we need to flash an older kernel that has the exploit and then reflash the kernel of our actual firmware version. This requires flashtool.

1. Download this archive and extract it.
2. Download the kernel file from 1.257 firmware.
3. If your actual firmware version is 2.245, download this kernel file. If it is 2.254, download this one.
4. Open flashtool, click on flash icon (see image), select flashmode, browse to 1.257 kernel ftf, validate.
5. Disconnect your device, shut it down, then while pushing on the volume down button plug your device to your computer. The illumination bar should go green.
6. Wait for flashtool to finish, then reboot.
7. CLOSE FLASHTOOL
8. In the extracted folder, run the runme_ file (exact name depends on your OS).
9. Once it is finished, shutdown your device.
10. Open Flashtool again, repeat the same steps as before, but select the kernel FTF for your actual version (2.245 or 2.254).
11. Plug your device in Flashmode.
12. When flashtool has finished, you can reboot and finally enjoy your root!

As for 12.0.A.2.245 and 12.0.A.2.254, the exploit is fixed, so we need to root while being on an older firmware (2.254 preferably), flash the new stock rom zip via recovery and flash the new kernel via Flashtool.(thanks to niaboc79 for this method).

1. Downloads:
   • 12.1.A.0.266 FTF (Full or Kernel Only)
   • Stock ROM deodexed or any stock based ROM of your choice
2. Update to 12.0.A.2.254.
3. Root using the 2nd method.
4. CLOSE FLASHTOOL
5. Unzip the recovery archive and run the .bat file.
6. Put the ROM and fix zip on your phone.
7. Reboot in recovery (Power Off your phone, then power on and press (not maintain) volume up on multiple times until it vibrates).
8. Flash the ROM.
9. Flash the fix.
10. Advanced -> Power Off
11. IF IT ASK YOU ABOUT A SU OVERWRITE, SELECT NO
12. Open flashtool and flash only the kernel from the .266 ftf. (see screenshot from niaboc79)
13. Unplug, power on and enjoy Android 4.3 with root!

Install Thunderzap Kernel Using Flashtool

Matthieu HarléMatthieu Harlé

protected by Community♦May 27 '14 at 17:24

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Once you unlock your Android’s Bootloader, changing the kernel is one of the many things that you can do with your Smartphone. The kernel is the piece of software that let’s the Android system to communicate with the hardware. Having a custom kernel has many advantages as follows:

• Overclocking the processor
• Provision for Undervolting the CPU (for battery saving)
• Two way call recording
• Zram script (improves performance)
• Init.d support (boot time tweaks initialization)

• Custom CPU scaling governors
• Custom I/O schedulers
• Support for EXT 2/3/4 file systems
• Pre-Rooted device
• Custom Recovery on Android

Sony Xperia Devices have a locked bootloader by default which prevents users from flashing a custom kernel or a custom ROM. Unlocking the bootloader enables you to flash a kernel in your device.

Usually kernels are ROM specific, hence the user is advised to do enough research regarding the particular kernel the user is about to flash.

Requirements for Flashing Kernel on Xperia devices

• Bootloader Unlocked of your Sony Xperia device (to unlock bootloader refer to Sony Official Unlock method)
• Android SDK (method 1)[refer to this guide: How to install Android SDK]
• Sony PC companion (for device specific drivers)
• Flashtools (Check method 2)
• Kernel to be flashed

Two techniques to flash a kernel in Xperia phones are listed below

Method 1: Using Fastboot (Android SDK)

1. Open the folder where you have installed the SDK. Example: C:/Users/XYZ/android-sdks/platform-tools
2. Now place the kernel IMG file that you wish to flash in this folder
3. Rename it to boot.img
4. Now press Shift + Right click and select Open Command Window here
5. Now Power Off your phone
6. Press and hold the Volume Up button and connect the device to the PC using USB cord.
7. A blue led will light up on your phone
8. Now type the code: fastboot devices into the CMD window.
9. If it returns a numeric value the phone is successfully connected in Fastboot mode.
10. Now type the command fastboot flash boot boot.img
11. If everything goes right it will show a success message and that’s all you successfully flashed a custom kernel
12. Disconnect your device and power it ON to boot into your system with the new kernel

Method 2: Using Flashtools

1. Once you install Flashtools, go to the directory where you installed it. Example: C:/Flashtool/drivers
2. Install the Flashtool-drivers.exe
3. Once finished open Flashtools/Flashtools64 depending on your PC’s processor (32bit or 64bit)
4. Now click on the lightening button on the upper left corner.
5. select Fastboot mode and press OK.
6. A window called as the Fastboot Toolbox will appear.
7. Now Power Off your phone.
8. Press and hold the Volume Up button and connect the device to the PC using USB cable
9. A blue led will light up on your phone
10. Now Select the option Select kernel to flash
11. Navigate to the folder where you placed the downloaded kernel IMG file and select it
12. Flashtools will flash the kernel and show a success message on the main screen
13. Press Reboot system

Done! Let us know your experience of Flashing a New Kernel on your Xperia with these methods.