Re: [libvirt] [Xen-devel] [PATCH] libxl: allow an <emulator> to be selected in the domain config XML

On Wed, May 01, 2013 at 02:44:11PM +0100, David Scott wrote: > On 01/05/13 09:46, Ian Campbell wrote: >> I would suggest that libvirt+libxl expose the version as the "emulator" >> option and not the path. Just leave the path as the default in the >> normal case. You may also want to provide an extra >> emulator-path-override tag/attribute/XML for advanced users, but that's >> up to you. >> >> If you need to support upgrade from xend then you could perhaps treat >> <emulator> values not in the set of valid LIBXL_DEVICE_MODEL_VERSION >> string (currently "qemu-xen" and "qemu-xen-traditional") as a path to a >> qemu-xen-traditional device model -- no xend user can possibly have been >> using the new device model with xend. Or you could take the approach >> that xl does and just warn. > > This would work for me: it doesn't seem too bad to consider > "qemu-xen" and "qemu-xen-traditional" as special virtual paths. It's > a useful observation that xend never supported the new device model. > Jim: should I cook up patch v3? :-) No, that really doesn't fly. The <emlator> element must always point to a qualfied binary path. IMHO, libvirt should just default to the new QEMU binary and if people want to use the old one, they can configure the emulator path for it.