[libvirt] Shared memoryBacking

Hi, While trying to add vhost-user-gpu support to libvirt, I am wondering how the guest should be configured to enable domain memory sharing. Naively, I thought this alone should work: <memoryBacking> <access mode='shared'/> </memoryBacking> But it doesn't seem to produce memory-backend-file share=on or memory-backend-memfd (the later would be better for my case) Any opinion on how to change that? thanks -- Marc-André Lureau