On 04/28/2014 03:38 AM, Paolo Bonzini wrote:
Il 04/04/2014 22:46, Eric Blake ha scritto:
I'm still not seeing what's wrong with depending on the version number since other features are also depending on the version number.
Every feature where we have to guess based on version number is due to a bug in qemu for not providing enough information for libvirt to probe for the feature's existence. We hate those features, and I have been lobbying hard on the qemu list that all NEW features should be discoverable. rdma is one such feature - I recall you making changes in your series there so that it is discoverable in response to my early review comments - so now please USE that methodology from libvirt.
I think that relied on the QAPI introspection. The MigrationCapability rdma-pin-all will be present only if QEMU supports RDMA migration.
But QAPI introspection is not there yet. :(
I know that qapi introspection is not there yet, but 'query-migrate-capabilities' IS there, and the presence or absence of rdma-pin-all in the set of queried capabilities IS a reliable witness of whether rdma support is available. -- Eric Blake eblake redhat com +1-919-301-3266 Libvirt virtualization library http://libvirt.org