Re: [libvirt] [PATCH v4 1/3] conf: Extend <loader/> and introduce <nvram/>

On 08/22/2014 10:43 AM, Daniel P. Berrange wrote: >>> &lt;os&gt; >>> &lt;type&gt;hvm&lt;/type&gt; >>> - &lt;loader&gt;/usr/lib/xen/boot/hvmloader&lt;/loader&gt; >>> + &lt;loader readonly='on' type='rom'&gt;/usr/lib/xen/boot/hvmloader&lt;/loader&gt; >> >> readonly='yes' is a bit more typical of other XML constructs. >> >>> + &lt;nvram&gt;/var/lib/libvirt/nvram/guest_VARS.fd&lt;/nvram&gt; >> >> You chose <nvram> to be a sibling, rather than a child, of <loader>. Is >> it legal to have <nvram> in isolation, or can it only appear when >> <loader> is present? If the former, then you are okay; if the latter, >> then I'd rather see it as a child than a sibling. > > <loader> is a long standing element whose contents is a string path. > So from a back compatibility POV we can't make <nvram> be a child > of that, even though it would make sense. Hmm. But what if we allow a choice between: <loader type='rom'>/path/to/rom</loader> and <loader type='pflash'> <config>/path/to/config</config> <nvram>/path/to/nvram</nvram> </loader> that is, use the (optional) type='rom|pflash' for gating whether the rest of the <loader> element is a single name (old style) or structured layout (new style)?