Comment 9 for bug 1561019

I was looking around for more info about this whole area and found we already were already looking at this once (bug 1494602). Unfortunately (as so often) the reporter went just quiet and at least I forgot about it. So essentially, to make things more fun, that qemu change affects VM differently depending on the machine type used. So for VMs created in/with Trusty this is ok but with later releases the default changed and one needs force the svm/vmx flag on. The provided XML shows a machine type of "pc-i440fx-vivid". So likely when that gets changed from vivid to trusty, then nested works.

Serge, not sure where that patch you refer to is located. I cannot find it. But generally adding vmx or svm probably has to be done very carefully as those are vendor specific. Not that this makes boot fail on all Intel CPUs...