: In x86_64, the AMD64 architecture requires that bits beyond the implementation limit (typically 48 bits) be all ones or all zeros. Negative address space can be used because paging is the only available memory model for 64-bit mode.
Historically, Android devices used a single set of partitions (boot, system, vendor, etc.). When a system update occurred, the phone had to reboot into a specialized recovery mode, apply the update, and then restart, making the device unusable for several minutes.
Ready to implement this on a Linux machine or SBC? Here is a practical guide using RAUC and GRUB . ab multiboot
This adds the ab_select command to your boot script.
A/B system updates enable reliable firmware updates by maintaining two complete sets of partitions. The architecture requires: : In x86_64, the AMD64 architecture requires that
Tesla’s infotainment system and many Linux-based car dashboards use AB Multiboot. The car can update its maps or driving algorithms while you drive, then ask you to apply the update "on next restart."
| Aspect | A/B for updates | A/B for multiboot | |--------|----------------|-------------------| | Safety | Update rollback safe | Switching slots retains both ROMs | | Storage | Requires ~2x space for system/vendor | Same limitation | | Multiboot ease | Not designed for it, but possible | Requires custom recovery or DSU | | Official support | Yes (since Android 7) | Only DSU (temporary GSI) | When a system update occurred, the phone had
This happens if the bootloader flags the secondary slot as "unbootable" due to an signature verification failure or an incompatible kernel.
This article dives deep into what AB Multiboot is, how it works, why it outperforms legacy setups, and how you can implement it on your own hardware.
This public link is valid for 7 days and shares a thread, including any personal information you added. This link or copies made by others cannot be deleted. If you share with third parties, their policies apply. Can’t copy the link right now. Try again later.
Whether you are an Android developer, a Linux power user, or an embedded systems engineer, understanding AB Multiboot is the key to unlocking robust multi-environment setups. What is AB Multiboot?