hm, I've built my image yesterday and has kernel 4.14.143 for R3Gv2 (what is pretty much the same device), yours has 4.19.57, maybe its really your image has a problem.
Could you share yours flash file ( from breed or from spi programmer ) with this version openwrt ?
I can't install any version openwrt with mounted overlay partition, so my router loose any setting over reboot.
Now I use padavan on this, but i will testing openwrt.
BTW From breed is impossible get working openwrt ( in my case ) any working compilation has no overlays mounted.
Breed only see partition 0x4000 0x5000 and 0x6000 for firmware - only initramfs kernel image working.
Is any solution for regen partiton table wiitch work with eg, openwrt-4a compilation ?
Not sure if this'll help because I think you mean an image for the Xiaomi 3G v2 (in that case don't flash this file) but otherwise here's a normal compiled kernel and sysupgrade image for the Xiaomi 4A Gigabit edition build from master (16-09-2019) snapshot and @rogerpueyo's original changeset with following packages added:
Can we keep this thread strictly Mi Router 4A hahaha, its soo confusing reading comments talking about image files for the 3G that are not even related or could help the 4A project.
I successfully installed the firmware (the version posted by kevinsa a few days ago) on mi Mi Router 4A using the bootloader unlock with the help of a flash memory programmer. So far so good, performance is excellent and now I have all the features from full OpenWRT (stock has IPv6 disabled!!!)
You can find the procedure in the first post of this thread, but basically you need to dump the SPI flash, modify a few bytes then write it. You need a CH341A programmer with a SOIC8 clamp (you can easily find them online for cheap)
I have bayed - CH341A programmer with a SOIC8 clamp understand how to get inside the FLASH memory then Dumping the SPI FLASH memory > Extracting the SPI FLASH memory content using binwalk > Modifying the U-Boot bootloader timeout > then what is next step .. Thanks for help