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Fix Slow Boot when using NetHunter on Android 16+ (Restorecon Loop)

Important

Credits

Original Discovery & Tool by: 5ec1cff
Based on the research regarding init behavior on Android 11+ and failed SELinux context restoration.

The Problem: Why your boot is slow

If you have a rooted device (especially with Kali Nethunter or massive number of files) and your boot time hangs on the first splash screen for minutes, you are likely stuck in a restorecon loop.

Technical Explanation

During the post-fs-data stage of the boot process, the Android init binary performs a check on the /data partition. It tries to ensure all files have the correct SELinux labels.

  • The Optimization: To avoid scanning millions of files every boot, Android calculates a hash based on the system's file contexts. If a scan completes successfully, it saves this hash into an extended attribute (xattr) on the /data folder called security.sehash.
  • The Check: On the next boot, init compares the current system hash with the one stored in security.sehash. If they match, it skips the scan.
  • The Failure: On some ROMs or heavy setups (like Nethunter), the restorecon process often fails mid-way (due to timeout, permission errors, or massive file counts in chroots).
  • The Loop: Because it fails, the hash is never written. Consequently, every single time you reboot, Android thinks it's a "fresh" update and tries to relabel every file in your Nethunter chroot again. This causes massive I/O wait and delays boot by minutes.

The Solution

The restorehash tool automates a workaround. Instead of letting the system fail repeatedly, it calculates the correct hash in a safe environment and forces it onto the /data directory.

Installation & Usage

Prerequisites

  • Termux (in root shell) or Android Root Shell (Nethunter Terminal)
  • The restorehash binary

Step-by-Step Guide

  • Place the Binary: Move the restorehash file to /data/local/
su
cp /sdcard/Download/restorehash /data/local/
  • Set Permissions: Give the binary executable permissions.
cd /data/local
chmod 777 restorehash
  • Run the Fix: Execute the tool with the restore argument.
./restorehash restore
  • Verify: If successful, the tool will update the security.sehash attribute. Reboot your device. The boot time should now be significantly faster (skipping the massive file scan)