On Fri, Nov 22, 2024 at 10:32:47PM +0100, Jiri Denemark wrote: > Each CPU model with -v* suffix is defined as a standalone model copying > all attributes of the previous version. CPU model versions with an alias > are handled differently. The full definition is used for the alias and > the versioned model is created as an identical copy of the alias. > > To avoid breaking migration compatibility of host-model CPUs all > versioned models are marked with <decode guest='off'/> so that they are > ignored when selecting candidates for host-model. It's not ideal but not > doing so would break almost all host-model CPUs as the new versioned CPU > models have all vmx-* features included since their introduction while > existing CPU models were updated later. This meas existing models would > be accompanied with a long list of vmx-* features to properly describe a > host CPU while the newly added CPU models would have those features > enabled implicitly and their list of features would be significantly > shorter. Thus the new models would always be better candidates for > host-model than the existing models. > > Signed-off-by: Jiri Denemark <jdenemar@xxxxxxxxxx> > --- Reviewed-by: Daniel P. Berrangé <berrange@xxxxxxxxxx> With regards, Daniel -- |: https://berrange.com -o- https://www.flickr.com/photos/dberrange :| |: https://libvirt.org -o- https://fstop138.berrange.com :| |: https://entangle-photo.org -o- https://www.instagram.com/dberrange :|
