LVM, add new logical partition to existing LV

Format that partition using mkfs:

[root@home cappuccino]# mkfs.ext4 /dev/sda8

Initialize it

[root@home cappuccino]# pvcreate /dev/sda8

add to existing VG:

[root@home cappuccino]# vgextend vg_home /dev/sda8

use it:

[root@home cappuccino]# lvresize /dev/vg_home/lv_root -L +3.93G

final step: boot into single user mode, and active new space for Logical volume group:

# mount -o remount,rw /path/to/lv
# resize2fs -f /path/to/lv

that's all.