[libvirt] How to disable kvm_steal_time feature

Hi. I would like to workaround a bug, when after live-migration of KVM guest, there is a 100% steal time shown in guest. I've read, that disabling 'kvm_steal_time' feature should workarund this bug, but i can't find a way to disable it in libvirt's domain xml file. Tried in <cpu> section: <feature policy='disable' name='kvm_steal_time'/> but that doesn't work. Also, couldn't find any related information in libvirt documentation. Google helps neither. How can I disable this feature? Thanks in advance. Piotr Rybicki