I’m developing for the Xavier and I’m looking into enabling OTA updates using L4T’s built-in A/B redundancy functionality. While I can see how I would go about creating a BUP for updating the various bootloader partitions and the kernel partitions, I’m not seeing a way to go about enabling redundancy for the rootfs partition (i.e. the APP partition). I can hack something together where I can flash two partitions (APP and APP_b), then change the rootdev cmdline parameter of kernel-dtb: for _a, I can set rootdev to point to mmcblk0p1, and for _b, I can set rootdev to point to mmcblk0p2. However, I don’t see how this would work with BUPs given that the update engine doesn’t seem to allow for separate partition data for _a and _b on the same partition name.
Is there an officially supported way to get rootfs A/B updates using, e.g. the BUP?