Hi list, i currently have the following issue: I did a test upgrade to libvirt 1.1.4 and now i cannot create new snapshots which can be reverted. Following Situation: Virtualization: kvm Disktype: qcow2 qemu XML: <cpu mode='host-passthrough'> </cpu> Creating of snapshot: virsh snapshot-create-as <guest> <name> <description> --atomic Now i craete a snapshot and as soon as i revert i get the following error: error : virCPUDefParseXML:367 : XML error: Non-empty feature list specified without CPU model I think the error is inside the snapshot xml (virsh snapshot-dumpxml): <cpu mode='host-passthrough'> <feature policy='require' name='pdpe1gb'/> <feature policy='require' name='osxsave'/> <feature policy='require' name='dca'/> <feature policy='require' name='pcid'/> <feature policy='require' name='pdcm'/> <feature policy='require' name='xtpr'/> <feature policy='require' name='tm2'/> <feature policy='require' name='est'/> <feature policy='require' name='smx'/> <feature policy='require' name='vmx'/> <feature policy='require' name='ds_cpl'/> <feature policy='require' name='monitor'/> <feature policy='require' name='dtes64'/> <feature policy='require' name='pbe'/> <feature policy='require' name='tm'/> <feature policy='require' name='ht'/> <feature policy='require' name='ss'/> <feature policy='require' name='acpi'/> <feature policy='require' name='ds'/> <feature policy='require' name='vme'/> </cpu> In older libvirt versions < 1.0.0 the xml looks the following way (virsh snapshot-dumpxml): <cpu mode='host-passthrough' match='minimum'> <model>SandyBridge</model> <vendor>Intel</vendor> <feature policy='require' name='pdpe1gb'/> <feature policy='require' name='osxsave'/> <feature policy='require' name='dca'/> <feature policy='require' name='pcid'/> <feature policy='require' name='pdcm'/> <feature policy='require' name='xtpr'/> <feature policy='require' name='tm2'/> <feature policy='require' name='est'/> <feature policy='require' name='smx'/> <feature policy='require' name='vmx'/> <feature policy='require' name='ds_cpl'/> <feature policy='require' name='monitor'/> <feature policy='require' name='dtes64'/> <feature policy='require' name='pbe'/> <feature policy='require' name='tm'/> <feature policy='require' name='ht'/> <feature policy='require' name='ss'/> <feature policy='require' name='acpi'/> <feature policy='require' name='ds'/> <feature policy='require' name='vme'/> </cpu> So for what ever reason the model and vendor tag are not copied inside the snapshot metadata xml when using cpu mode cpu-passthrough. virsh dumpxml with --update-cpu flag reports the correct cpu node with model and vendor tags. After a stop of libvirtd and loooking inside the xml file the cpu tag looks the following: <cpu mode='host-passthrough' match='minimum'> <model>SandyBridge</model> <vendor>Intel</vendor> <feature policy='require' name='pdpe1gb'/> <feature policy='require' name='osxsave'/> <feature policy='require' name='dca'/> <feature policy='require' name='pcid'/> <feature policy='require' name='pdcm'/> <feature policy='require' name='xtpr'/> <feature policy='require' name='tm2'/> <feature policy='require' name='est'/> <feature policy='require' name='smx'/> <feature policy='require' name='vmx'/> <feature policy='require' name='ds_cpl'/> <feature policy='require' name='monitor'/> <feature policy='require' name='dtes64'/> <feature policy='require' name='pbe'/> <feature policy='require' name='tm'/> <feature policy='require' name='ht'/> <feature policy='require' name='ss'/> <feature policy='require' name='acpi'/> <feature policy='require' name='ds'/> <feature policy='require' name='vme'/> </cpu> After the start of libvirtd virsh reports the cpu tag with missing vendor and model. Does anybody else has this problem? Best regards Georg