wont take any upgrade now
root@OpenWrt:/sbin# ./block info
/dev/mtdblock5: UUID=“147157xxxx” VERSION=“1” TYPE=“ubi”
/dev/ubiblock0_0: UUID=“axxxxx76-44e69463-38cf809c-b6xxxxx” VERSION=“4.0” MOUNT=“/rom” TYPE=“squashfs”
/dev/ubi0_1: UUID=“6xxxxxx26c1-9241-461e-9974-474cxxxxx” VERSION=“w4r0” MOUNT=“/overlay” TYPE=“ubifs”