OK, seems a stock RHEL 6.6. I wonder if the recommended hv settings
are really supported on old QEMUs. Need to check about this: will do and will report.

If you'll be the most welcome to file a bug against oVirt for this issue,
and set target release to 3.5.1, so we can track this issue.

Looks like I need to search RedHat bugzilla a bit better.  Issues for this already exist:

https://bugzilla.redhat.com/show_bug.cgi?id=1063124
https://bugzilla.redhat.com/show_bug.cgi?id=1069082

Charles