All these devices think that the mtd2, Config partition is the u-boot-env partition, but it isn't.
And if someone got a serial connection and do a saveenv it will destroy the OpenWrt installation.
Because the real u-boot-env partition is the params partition:
dev: size erasesize name
mtd0: 00800000 00010000 "ALL"
mtd1: 00030000 00010000 "Bootloader"
mtd2: 00010000 00010000 "Config"
mtd3: 00010000 00010000 "Factory"
mtd4: 00180000 00010000 "Kernel_RootFS"
mtd5: 00010000 00010000 "params"
mtd6: 00010000 00010000 "user_backup"
mtd7: 00010000 00010000 "user"
mtd8: 00600000 00010000 "Rootfs"
See discussion at the HooToo TM05 PR!
Another bad thing that these HooToo / RAVPower devices are limited to 1536 K kernel size: the u-boot reads only 0x180000 bytes at start and bad crc occurs when OpenWrt kernel exceeds this.
For example: Ravpower wd03 does not start with openwrt master - #9 by jeff