I built my own firmware for raspberry. But I can not save any changes (new folders, files, configs) after rebooting.
ouput of mount; df -h:
root@miromico:~# mount; df -h
/dev/root on /rom type squashfs (ro,relatime)
proc on /proc type proc (rw,nosuid,nodev,noexec,noatime)
sysfs on /sys type sysfs (rw,nosuid,nodev,noexec,noatime)
cgroup2 on /sys/fs/cgroup type cgroup2 (rw,nosuid,nodev,noexec,relatime,nsdelegate)
tmpfs on /tmp type tmpfs (rw,nosuid,nodev,noatime)
tmpfs on /tmp/root type tmpfs (rw,noatime,mode=755)
overlayfs:/tmp/root on / type overlay (rw,noatime,lowerdir=/,upperdir=/tmp/root/upper,workdir=/tmp/root/work)
tmpfs on /dev type tmpfs (rw,nosuid,relatime,size=512k,mode=755)
devpts on /dev/pts type devpts (rw,nosuid,noexec,relatime,mode=600,ptmxmode=000)
debugfs on /sys/kernel/debug type debugfs (rw,noatime)
none on /sys/fs/bpf type bpf (rw,nosuid,nodev,noexec,noatime,mode=700)
Filesystem Size Used Available Use% Mounted on
/dev/root 12.3M 12.3M 0 100% /rom
tmpfs 1.9G 72.0K 1.9G 0% /tmp
tmpfs 1.9G 120.0K 1.9G 0% /tmp/root
overlayfs:/tmp/root 1.9G 120.0K 1.9G 0% /
tmpfs 512.0K 0 512.0K 0% /dev
version is OpenWrt 21.02.1, r16325-88151b8303
root@miromico:~# cat /etc/banner
_______ ________ __
| |.-----.-----.-----.| | | |.----.| |_
| - || _ | -__| || | | || _|| _|
|_______|| __|_____|__|__||________||__| |____|
|__| W I R E L E S S F R E E D O M
-----------------------------------------------------
OpenWrt 21.02.1, r16325-88151b8303
-----------------------------------------------------
Please, help, how to fix it?