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If an override was in place on > >> the source host, an override will also need to be put in place on the destination > >> one. > > > > But they may be malfunctioning before already, if started on a > > vulnerable hosts without this fix and having seen RDSEED? > > Yes. But there could also be ones coming from good hosts. Imo ... > > > IMO after this fix is applied you should do pool leveling, at which > > point RDSEED shouldn't be advertised anymore. Having the feature in > > the max policy allows to evacuate running guests while updating the > > pool. Otherwise those existing guests would be stuck to run on > > non-updated hosts. > > ... we need to err on the side of caution. While I understand your concerns, this would cause failures in the upgrade and migration model used by both XCP-ng and XenServer at least, as it could prevent eviction of running VMs to updated hosts. At a minimum we would need an option to allow the feature to be set on the max policy. Overall I think safety of migration (in this specific regard) should be enforced by the toolstack (or orchestration layer), rather than the hypervisor itself. The hypervisor can reject incompatible policies, but should leave the rest of the decisions to higher layers as it doesn't have enough knowledge. Thanks, Roger.