Hi,
We cannot just start enforcing that the vram attribute should be
power
of 2. We can ether silently modify the value from user to power of 2 or
let QEMU round the value up to nearest power of 2 value and just add
a note about this to documentation.
How about simply ignoring vram in case it has a invalid value? This way
current behavior is maintained for existing xml files (not pass anything
and let qemu use the defaults).
Whenever libvirt applies fixups to the xml (like adding pci controllers
to old xml configs, as done on "virsh edit" for example) libvirt can
also fixup vram to have a valid value.
cheers,
Gerd