Get rid of that f..ng "permission denied" error when using -acpitable file=/.. option in libvirt XML guest definition file.

ABSTRACT:

This post relates to how to activate an OEM windows10 when it runs as a kvm guest controlled by libvirt, getting rid of that f..ng "permission denied" you
get using the qemu:arg ... -acpitable command line option within the libvirt XML guest definition file.

WHAT TO DO IF YOU ARE IN HURRY:

Grab your product key out of MSDM ACPI table.
Place your SLIC.bin file in /usr/share/seabios directory and have the XML line to point at it.
<qemu:arg value='-acpitable'/>
<qemu:arg value='file=/usr/share/seabios/SLIC.bin'/>

Run your guest, go to Windows and activate it using the product key you grabbed from MSDM.
Done.

DETAILS:

Installing an HP OEM Windows 2012 R2 Essential server as KVM Guest

I have an HP Proliant DL385p Gen8 box together with a HP/OEM installation disk of Windows Server 2012 R2 Essential.
On the iron I've installed Ubuntu Server 12.04.5 64bit plus xfce 4.1 (horrible: avoid it!) and KVM latest version available in ubuntu repository at the time of this writing (Dec2014).
The windows server is going to run as a guest over KVM. I have plenty of configurations like this perfectly working where, however, the Windows software is not OEM..
Here, a little while after the windows server installation CD boots up in the guest, it stops with the following message:"This system is not a supported platform": the hardware platform must be an HP and the actual one is not. No way.