This is for the 8th gen Fire HD8 (karnak).
Current version: amonet-karnak-v3.0.1.zip
This is based on @xyz`s original work, but adds some features such as reboot to hacked BL.
It also intends to simplify the installation process.
If you are already unlocked you can simply update by flashing the ZIP-file in TWRP.
NOTE: If you are on a firmware lower than 220.127.116.11 this process does not require you to open your device, but should something go horribly wrong, be prepared to do so.
What you need:
- A Linux installation or live-system
- A micro-USB cable
Install python3, PySerial, adb, fastboot dos2unix. For Debian/Ubuntu something like this should work:
sudo apt update sudo add-apt-repository universe sudo apt install python3 python3-serial adb fastboot dos2unix
NOTE: If you are already rooted, continue with the next step, otherwise get mtk-su by @diplomatic from here and place (the unpacked binary) into amonet/bin folder
2. Enable ADB in Developer Settings
3. Start the script:
NOTE: If you are on a firmware newer than 18.104.22.168, a downgrade is necessary, this requires bricking the device temporarily. (The screen won't come on at all)
WARNING: There have been numerous reports that would indicate a hardware-change that doesn't allow access to the bootrom.
When bricking these devices there is currently no known way to unbrick.
This makes the hardware-method currently the safest option.
To brick firmware 22.214.171.124 use the attached brick-karnak.zip, boot into fastboot
adb reboot bootloader
sudo systemctl stop ModemManager sudo systemctl disable ModemManager
The device will reboot into TWRP.
You can now install Magisk from there.
Going back to stock
Extract the attached zip-file "amonet-karnak-return-to-stock.zip" into the same folder where you extracted "amonet-karnak-v3.0.1.zip" and open a terminal in that directory.
Don't flash boot/recovery images from FireOS (FlashFire, MagiskManager etc.)
TWRP will prevent updates from overwriting LK/Preloader/TZ, so generally installing an update should work without issues (only full updates, incremental updates won't work).
For ROM developers there is still an option to overwrite these, which should only be done after thorough testing and if needed (LK should never be updated).
It is still advised to disable OTA.
Very special thanks to @xyz` for making all this possible and putting up with the countless questions I have asked, helping me finish this.
Special thanks also to @diplomatic for his wonderfull mtk-su, allowing you to unlock without opening the device.
Thanks to @Kaijones23 for testing.