For anyone wondering what's going on, the intention of this BZ is to validate the 'QemuMemoryBackingDir' parameter, added in #1594272. Validating that requires enabling file-backed memory so we have something to store on disk, which means we've also validated the related 'NovaLibvirtFileBackedMemory' parameter. I've renamed the BZ to better indicate this.
According to our records, this should be resolved by openstack-tripleo-heat-templates-11.3.2-0.20200616081532.396affd.el8ost. This build is available now.
According to our records, this should be resolved by puppet-nova-15.5.1-0.20200608173427.c15e37c.el8ost. This build is available now.