kernel dev network (virsh based). and sample qemu vm on it

Network.xml

<network>
  <name>kernel-net</name>
  <uuid>5618453a-d6af-42f5-b77d-eb1727371b73</uuid>
  <forward mode='nat'>
    <nat>
      <port start='1024' end='65535'/>
    </nat>
  </forward>
  <bridge name='kerneldevbr0' stp='on' delay='0'/>
  <mac address='42:ef:c9:0b:a4:f1'/>
  <ip address='192.168.124.1' netmask='255.255.255.0'>
    <dhcp>
        <range start='192.168.124.2' end='192.168.124.254'/>
    </dhcp>
  </ip>
</network>

start-vm.sh

# create the above network with `virsh net-create ./network.xml`
# Generating mac here. in reality you probably want to use static mac
# if you want to assign static ip for discovery 
# check: https://libvirt.org/formatnetwork.html
sudo qemu-system-x86_64 \
-smp 4 \
-m 8192 \
-enable-kvm 
-nographic \
--drive file=${IMG_DISK},if=virtio,cache=writethrough,index=0 \
--netdev bridge,br=kerneldevbr0,id=deb001 --device virtio-net-pci,netdev=deb001,id=nicdeb001,mac=$(printf '52-54-00-%02X-%02X-%02X\n' $[RANDOM%256] $[RANDOM%256] $[RANDOM%256]) \
-append ' root=/dev/vda console=ttyS0' \
-kernel ./vmlinuz-4.4.0-127-generic