I hope ... it is the last question from me. Do I need to edit etc/fstab to add permanent root about that "mount /dev/mmcblk0p4 /mnt/debian" or there is better method? What options/argumennt other that "/dev/mmcblk0p4" and "/mnt/debian" I need to put?

Add1: Seems I have bigger problem. When I try to mount /dev/mmcblk0p4 to /mnt/debian my phone starts loading the CPU at 100%. This does not allow me even to try the ED on the phone.
Sure I will try to serch the tread and the forum, but if you already have the idea what is causing this, please help.