building ramdisk and busybox

nice link1

nice link2

building root file system has three critical sections:

/lib --> many utilized static and dynamic libs

/usr/bin /bin /sbin.... --> busybox

/etc --> most critical binary file in here

*/dev --> console device must have, the other device always create from kernel

build easy file system

#create a zero file by loopback device, note that the "count" must set a finite number
dd if=/dev/zero of=fs.ext2 bs=32768k count=1

#usnig /sbin/mke2fs to create a ext2 file system
/sbin/mke2fs fs.ext2
Proceed anyway? y

#mount fs.ext2 to your host anywhere and u can make your root folder easy.
mount -o loop fs.ext2 your-mount-folder

#building rootfs

/lib/*.so dependency with execution file that can check by arm_v5t_le-readelf

#busybox, close the task set from micellaneous... utility

make menuconfig

make ARCH=arm CROSS_COMPILE=arm_v5t

make install ARCH=arm CROSS_COMPILE=arm_v5t