Before the image can be used, it must be decompressed.
| Issue | Solution |
|-------|----------|
| Invalid sparse file format | Use fastboot flash --force |
| Doesn't boot after flash | Verify A/B slot: fastboot getvar current-slot |
| Size too large for partition | Resize partition or use fastboot flash --slot=_a system |
| Emulator fails to boot | Wipe userdata: -wipe-data flag |
Because this is an A/B device, you must know which slot is active. Usually, you can flash to both slots or just the current slot: system-arm64-ab.img.xz android 12
Option A (recommended): Flash to current slot only
fastboot flash system system-arm64-ab.img
Option B (safer for seamless updates): Flash to both slots Before the image can be used, it must be decompressed
fastboot flash system_a system-arm64-ab.img
fastboot flash system_b system-arm64-ab.img
ro.build.version.release=12
ro.build.version.sdk=31
ro.product.cpu.abi=arm64-v8a
ro.build.system_root_image=true
ro.build.ab_update=true
You typically obtain this file from:
For Android 12, Google provides official GSIs to help developers and power users test Android on Treble-compatible devices without waiting for OEM updates. Because this is an A/B device, you must
For Android 12L (12.1) and Android 13, the naming scheme remains identical: system-arm64-ab.img.xz. However, newer images may include Virtual A/B (where even the super partition is dynamic). In that case, you would flash to super rather than system:
fastboot flash super system-arm64-ab.img
Check the GSI documentation for the exact target partition—it varies by Android version.
While standard x86 images are preferred for speed on Intel/AMD computers, arm64 images are required when simulating the exact behavior of a physical mobile device on an architecture like Apple Silicon (M1/M2/M3) or when testing apps that rely on specific ARM native libraries (.so files) that cannot be translated on x86.