---

ubidetach -p /dev/mtd19
dd if=/dev/zero bs=8192 count=1 >> /tmp/factory.ubi
ubiformat /dev/mtd19 -y -f /tmp/factory.ubi
nvram set flag_boot_rootfs=1
nvram set flag_last_success=1
nvram set flag_boot_success=1
nvram commit
reboot