On 04/13/2016 03:09 AM, George Dunlap wrote:
Wei Liu wrote:
Hi libvirt maintainers, Sorry for the delay. Slowly catching up on mail after vacation...
Xen's control library libxenlight (libxl) requires application (libvirt in this case) to explictily define LIBXL_API_VERSION. Where is this requirement written? :-)
This is lacking at the moment so libvirt's libxl driver always gets the latest APIs. IMO, that is what we want for upstream libvirt. Downstreams can choose a specific version if they want. I think one of us isn't understanding the situation properly. Is it not the case that currently, all releases of libvirt *will not compile* against Xen 4.7 once it's released? So people downloading and building libvirt will have to either 1) root around and try to
On Tue, Apr 12, 2016 at 10:31 PM, Jim Fehlig <jfehlig@suse.com> wrote: figure out what version of Xen it will build against, 2) manually add in a #define *with the correct API version* to a header somewhere to make it build properly, or 3) update to a version of libvirt that supports the new api (which at the moment hasn't even been released yet)?
All of those options are completely unacceptable. Older versions of libvirt should Just Work when compiled against newer versions of Xen.
Yes, agreed. In practice though folks want a new libvirt with the new Xen, which is probably why no one has complained thus far. I'll knock up a patch to set the LIBXL_API_VERSION to 0x040200. The only APIs that have changed since 0x040200 are libxl_set_vcpuaffinity and libxl_domain_create_restore, but libvirt does not use the changes (added params). libvirt does use new libxl APIs added since Xen 4.2, but those aren't tied to a specific LIBXL_API_VERSION. Regards, Jim