On 05/02/2018 17:44, Tan, Jianfeng wrote: >>> >> I understand. However it's not as bad as "there's no possibility at all >> to migrate from vhost-kernel to vhost-user". There are cases that are >> more problematic: for example, there's no possibility at all to add >> memory NUMA policy during a live migration, unless -object >> memory-backend-* was used on the source. > > Please help me to understand: Are you saying it's always recommended to > use -object memory-backend-* configuration even with vhost-kernel > backend for the reason you mentioned?
Indeed---in general, there's no downside to always using -object to start a virtual machine. Of course when migrating a machine that was started without -object, you need to use it on the destination too. Paolo
