Hi, I guess this is the wrong approach: Libvirt does manage cpu type in an xml file, you would have to alter this xml file: /usr/share/libvirt/cpu_map.xml HTH PS: Maybe add an feature request upstream to enable this for all libvirt users? I have seen this request quite some time on different mailing lists. Am 27.08.2014 20:08, schrieb Nathan March: > On 8/26/2014 4:52 PM, Nathan March wrote: >> >> Has anyone here managed to get cpu masking working via libvirt? >> Intention to enable VM migrations between hosts of a different CPU >> generation. >> > > To add to this, I've tried using the boot options to set the cpu mask > instead: > > xen_commandline : dom0_mem=2048M,max:2048M loglvl=all > guest_loglvl=all cpuid_mask_ecx=0x009ee3fd cpuid_mask_edx=0xbfebfbff > > Unfortunately still no luck. There's no errors in xm dmesg to indicate > the settings were / weren't applied, it simply doesn't seem to do anything. > > - Nathan > _______________________________________________ > CentOS-virt mailing list > CentOS-virt at centos.org > http://lists.centos.org/mailman/listinfo/centos-virt > > > -- Mit freundlichen Grüßen / Regards Sven Kieske Systemadministrator Mittwald CM Service GmbH & Co. KG Königsberger Straße 6 32339 Espelkamp T: +49-5772-293-100 F: +49-5772-293-333 https://www.mittwald.de Geschäftsführer: Robert Meyer St.Nr.: 331/5721/1033, USt-IdNr.: DE814773217, HRA 6640, AG Bad Oeynhausen Komplementärin: Robert Meyer Verwaltungs GmbH, HRB 13260, AG Bad Oeynhausen