Re: [libvirt] [PATCH v2 1/3] conf: Extend <loader/> and introduce <nvram/>

Up to now, users can configure BIOS via the <loader/> element. With the upcoming implementation of UEFI this is not enough as BIOS and UEFI are conceptually different. For instance, while BIOS is ROM, UEFI is programmable flash (although all writes to code section are denied). Therefore we need new attribute @type which will differentiate the two. Then, new attribute @readonly is introduced to reflect the fact that some images are RO. Moreover, the OVMF (which is going to be used mostly), works in two modes: 1) Code and UEFI variable store is mixed in one file. 2) Code and UEFI variable store is separated in two files The latter has advantage of updating the UEFI code without losing the configuration. However, in order to represent the latter case we need yet another XML element: <nvram/>. Currently, it has no additional attributes, it's just a bare element containing path to the variable store file.