[libvirt] [PATCH v3] Support for cpu64-rhel* qemu cpu models

Daniel P. Berrange berrange at redhat.com
Tue Feb 21 14:54:39 UTC 2012


On Mon, Feb 13, 2012 at 03:32:26PM +0100, Jiri Denemark wrote:
> On Fri, Feb 10, 2012 at 11:22:09 -0700, Eric Blake wrote:
> > On 01/30/2012 09:25 AM, Martin Kletzander wrote:
> > > In qemu there are 2 cpu models (cpu64-rhel5 and cpu64-rhel6) not
> > > supported by libvirt. This patch adds the support with the flags
> > > specifications from /usr/share/qemu-kvm/cpu-model/cpu-x86_64.conf
> > > ---
> > > v3:
> > >  - fixed sse3 naming (it's 'pni' in the features)
> > > 
> > > v2:
> > >  - removed duplicated entries
> > > 
> > >  src/cpu/cpu_map.xml |   66 +++++++++++++++++++++++++++++++++++++++++++++++++++
> > >  1 files changed, 66 insertions(+), 0 deletions(-)
> > 
> > I'm assuming that you tested this (I did not spend the time meticulously
> > cross-checking qemu with this list).  Upstream qemu does not provide
> > these machine names; they are RHEL-specific.
> > 
> > Is it going to be an issue where we use libvirt on something like F16
> > where qemu does not have these machine names?  Or is it okay for libvirt
> > to have a larger list of machine names, to make out-of-box installation
> > of newer libvirt onto older RHEL/CentOS machines just work with those
> > new names?
> 
> It was designed to be okay. Libvirt checks what CPU models are supported by
> qemu and avoids passing unsupported models to qemu. After all, we support
> running libvirt with older releases of qemu (we don't force their git HEAD).

One day we should just stop using '-cpu', and simply write out a config
file where we can put a full '[cpudef]' definition, and pass it to QEMU
using -loadconfig. This will allow us to specify precise CPU models,
without being tied to particular QEMU versions. It will also allow the
end user / mgmt app to define new CPU models for libvirt to use.

Daniel
-- 
|: http://berrange.com      -o-    http://www.flickr.com/photos/dberrange/ :|
|: http://libvirt.org              -o-             http://virt-manager.org :|
|: http://autobuild.org       -o-         http://search.cpan.org/~danberr/ :|
|: http://entangle-photo.org       -o-       http://live.gnome.org/gtk-vnc :|




More information about the libvir-list mailing list