Re: [libvirt] [virt-tools-list] exposing host-passthrough in virt-manager ui?

On Wed, Feb 06, 2019 at 11:22:01AM -0500, Cole Robinson wrote: > On 2/6/19 10:57 AM, Pavel Hrdina wrote: >> On Wed, Feb 06, 2019 at 10:20:38AM -0500, Cole Robinson wrote: >>> On 2/5/19 6:19 PM, Hetz Ben Hamo wrote: >>>> Is it possible to add in the virt-manager the "host-passthrough" to the >>>> CPU models please? >>>> >>> >>> You can type 'host-passthrough' into the field and it will work. The reason >>> we don't advertise it is because it's considered to have some mild >>> supportability issues with libvirt. For the vast majority of use cases >>> though it's completely fine >> >> Maybe we can reconsider this decision, the only thing that would not >> work is live migration to destination with different CPU and we can >> have a warning/info about it in the UI. >> >> Possibly we could allow to set 'host-passthrough' as the default guest >> CPU in virt-manager config. >> > > Nowadays with host-model being much smarter, is there much functional > difference between host-model and host-passthrough? I don't really know the > answer. > >> Most workstation/desktop users of virt-manager probably doesn't care >> about live migration and it would copy the host CPU as closely as >> possible. Since we allow to manually type in 'host-passthrough' I >> personally don't see any reason why it cannot be selectable. >> > > The problem I see is that host-passthrough sets the libvirt 'taint' flag on > the VM. While it doesn't have any real impact on end users generally I took > that to mean 'you are doing something that is unsupported'. We should probably remove that, or at least only taint /after/ a live migration.