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KartikJha
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Unlocking Android Bootloader and Flashing GSI: A Complete Guide for Motorola Edge 40 Neo

#security #android #linux #tutorial

A comprehensive walkthrough of unlocking your Android device's bootloader and preparing for GSI installation

Introduction

Have you ever wanted to take full control of your Android device? Whether it's for installing custom ROMs, removing bloatware, or enhancing security, unlocking your bootloader is often the first step. In this guide, I'll walk you through the complete process I followed to unlock the bootloader on my Motorola Edge 40 Neo and prepare it for GSI (Generic System Image) flashing.

Prerequisites

Before we begin, make sure you have:

  • ADB and Fastboot tools installed
  • USB debugging enabled on your device
  • A backup of important data (this process will wipe your device)
  • Patience - this process takes time!

Step 1: Checking Bootloader Status

First, let's verify if your bootloader is locked:

adb shell getprop ro.boot.flash.locked
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If the output is 1, your bootloader is locked and needs to be unlocked.

Step 2: Installing Fastboot

If you don't have fastboot installed, you'll need to install it first. You can find installation guides for your specific operating system.

Step 3: Entering Fastboot Mode

Boot your device into fastboot mode:

adb reboot bootloader
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Step 4: Attempting to Unlock

For Android 10+ devices, try:

fastboot flashing unlock
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For older devices, use:

fastboot oem unlock
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In my case with the Motorola Edge 40 Neo, I needed to use:

fastboot flashing unlock_critical
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However, this failed with a message indicating that an unlock code was required.

Step 5: Getting the Unlock Data

When a standard unlock fails, you need to get the unlock data string:

fastboot oem get_unlock_data
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This command returned multiple lines of data that I had to concatenate into a single unlock string:

<128_CHARS_UNLOCK_KEY>
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Step 6: Obtaining the Unlock Key

With the unlock string ready:

  1. Visit Motorola's official bootloader unlock page
  2. Log in with your email
  3. Paste the unlock string
  4. Follow the on-screen instructions
  5. If your device supports unlocking, you'll receive an unlock key via email

Step 7: Unlocking the Bootloader

Once you have the unique key:

fastboot oem unlock UNIQUE_KEY
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⚠️ Warning: This will wipe all user data and reset your phone to factory state.

Preparing for GSI Installation

After successfully unlocking the bootloader, I prepared for GSI (Generic System Image) installation.

Checking Project Treble Compatibility

First, verify if your device supports Project Treble:

adb shell getprop ro.treble.enabled
# Should return: true

adb shell getprop ro.boot.dynamic_partitions
# Should return: true
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Determining Partition Scheme

Check your device's partition scheme to select the correct GSI build:

adb shell getprop ro.build.ab_update
# Returns: true (indicates A/B partition scheme)

adb shell getprop ro.product.cpu.abi
# Returns: arm64-v8a (indicates 64-bit ARM architecture)
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Based on these results, I needed a GSI build with the -ab suffix for A/B partition devices.

Challenges Encountered

Device Information

Using this command to identify the correct TWRP version:

adb shell "echo -n 'Model: '; getprop ro.product.model; echo -n 'Codename: '; getprop ro.product.device; echo -n 'Android Version: '; getprop ro.build.version.release; echo -n 'CPU: '; getprop ro.board.platform"
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Output:

Model: motorola edge 40 neo
Codename: manaus
Android Version: 14
CPU: mt6879
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Unfortunately, there was no official TWRP version available for this specific device.

Backup Attempts

I attempted to backup the existing OS using MTKClient, but encountered authentication errors. The tool requires specific auth and DA files for this MediaTek-based device.

As an alternative approach, I considered:

  1. Downloading the stock firmware
  2. Patching the boot image with Magisk
  3. Flashing the firmware as a backup solution

Next Steps

The process is ready for GSI flashing, which involves:

  1. Downloading the appropriate AOSP GSI from Google's developer resources
  2. Flashing the system image
  3. Copying additional components (vbmeta.img, etc.) from stock firmware

Security Considerations

This process was partly motivated by security concerns regarding potential intrusions. If you're dealing with similar security issues on your Android device, bootloader unlocking and custom ROM installation can be effective countermeasures.

Conclusion

Unlocking an Android bootloader requires patience and careful attention to detail. Each device manufacturer has slightly different procedures, and newer devices often have additional security measures. Always:

  • Research your specific device thoroughly
  • Backup important data
  • Understand that warranty may be voided
  • Be prepared for potential risks

The journey to a fully customized Android experience starts with this crucial first step. While the process can be complex, the freedom to control your device's software makes it worthwhile for many enthusiasts.

Tags

android bootloader motorola gsi customrom projecttreble fastboot adb mobilesecurity tutorial

Have you unlocked your device's bootloader? Share your experiences and any challenges you faced in the comments below!

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