UPDATE: I should have first looked at bugs.openwrt.org - this has been reported for a while but not fixed so far.
Overlay data is kept after sysupgrades and thus breaks upgrades.
- Install fresh image
touch /root/foo /etc/bar
sysupgrade -n -v openwrt-21.02.0-rc3-rockchip-armv8-friendlyarm_nanopi-r2s-squashfs-sysupgrade.img.gz
after boot the files
/etc/bar are still there potentially hiding what sits in /rom/etc/bar if it existed. If I manually add a jff2reset to the sysupgrade scripts, the upgrade behaves like it should. Any ideas why this is happening?
Tested and validated on: Friendlyarm R2S with 21.02.0-rc3 and snaptshot image: