SKYHOUSE.dev Journal

Why: We wanted to turn an old Fire 7 (2015, "ford") into a single-purpose kiosk, and its bootloader exploit has to run from a Linux host over USB, so this server became the flashing station.

Over a few sessions (Oct 5–8) we unlocked the tablet with k4y0z's amonet exploit, installed TWRP, and flashed LineageOS 14.1. The only lasting change to the server is one new package; the brltty masking was temporary and is reverted. The project itself lives in /home/plex/dev/fire, with a running log in NOTES.md.

1. Packages

• Action: I installed fastboot (apt install fastboot). adb and python3-serial were already present.

2. brltty, masked and restored

brltty is known to claim MediaTek bootrom serial ports (/dev/ttyACM*) during the exploit, so I masked brltty-udev.service and brltty.service for the duration. Once the tablet was unlocked I unmasked both; they're back to their original state (static / disabled). ModemManager was already inactive and wasn't touched.

3. Lessons for next time

• Don't run amonet's bootrom-step.sh in the background: it stops at an Enter prompt, and the half-finished run disables the SoC watchdog and leaves the bootrom wedged until the battery fully drains (that cost us about three days).
• Backups of the stock partitions live in /home/plex/dev/fire/backups/stock-20261008 (1.3 GB, with MD5SUMS).

Net effect: one extra package on the server; the tablet now runs LineageOS 14.1.