title: qemu displays and hangs with message 'booting from harddisk '
body: <p>I'm using Debian image with QEMU. Installation works well with below 
  command.</p>
  
  <pre class="lang-sh prettyprint-override"><code>ISO_FILE="debian-buster-DI-alpha5-amd64-xfce-CD-1.iso"
  DISK_IMAGE="debian.img"
  SPICE_PORT=5924
  
  qemu-system-x86_64 \
      -cdrom "${ISO_FILE}" \
          -drive format=raw,if=pflash,file=/usr/share/ovmf/OVMF.fd,readonly \
          -drive file=${DISK_IMAGE:?} \
          -enable-kvm \
          -m 2G \
          -smp 2 \
          -cpu host \
          -vga qxl \
          -serial mon:stdio \
          -net user,hostfwd=tcp::2222-:22 \
          -net nic \
          -spice port=${SPICE_PORT:?},disable-ticketing \
          -device virtio-serial-pci \
          -device virtserialport,chardev=spicechannel0,name=com.redhat.spice.0 \
          -chardev spicevmc,id=spicechannel0,name=vdagent 
  </code></pre>
  
  <p>But when I start the image again with command like </p>
  
  <pre class="lang-sh prettyprint-override"><code>DISK_IMAGE="debian.img"
  SPICE_PORT=5924
  
  qemu-system-x86_64 \
          -drive format=raw,if=pflash,file=/usr/share/ovmf/OVMF.fd,readonly \
          -drive file=${DISK_IMAGE:?} 
          -enable-kvm \
          -m 2G \
          -smp 2 \
          -cpu host \
          -vga qxl \
          -serial mon:stdio \
          -net user,hostfwd=tcp::2222-:22 \
          -net nic \
          -spice port=${SPICE_PORT:?},disable-ticketing \
          -device virtio-serial-pci \
          -device virtserialport,chardev=spicechannel0,name=com.redhat.spice.0 \
          -chardev spicevmc,id=spicechannel0,name=vdagent \
          -snapshot
  
  </code></pre>
  
  <p>QEMU stuck at <code>booting from harddisk</code> . Any thoughts on how resolve this and move 
  forward?</p>