Red Hat Bugzilla – Bug 858216
libvirt_cpu_mode defaults to host-model for kvm and qemu
Last modified: 2014-06-18 03:00:03 EDT
Description of problem:
When an instance is spun up on a VM running openstack (as opposed to bare metal), we see the following error in the nova-compute logs:
"libvirtError: unsupported configuration: CPU specification not supported by hypervisor"
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Version-Release number of selected component (if applicable):
Steps to Reproduce:
1. Boot an instance
Instance status goes to error.
Instance status goes to error.
Jiri, do you have any knowledge of problems with setting CPU models when running a QEMU instance inside a KVM guest. The scenario is that OpenStack sets mode="host-model" for all guests by default, this works fine running guest on bare metal, but fails when running inside a guest.
Ah, I guess it fails because libvirt is not able to match host CPU with any CPU model it knows about. Can you confirm that by running 'virsh capabilities' and checking the <cpu> element there? If that's the case, the host is likely masking some CPU features that are comonly present in all CPU models. A feature called "sep" is known to be missing in guests running on RHEL hosts, for example.
This package has changed ownership in the Fedora Package Database. Reassigning to the new owner of this component.
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