1. A computer-implemented method, comprising: receiving, by a hypervisor executed by a processing device, a memory page from a guest; returning, by the hypervisor, the memory page to the guest; and notifying the guest in a message from the hypervisor that the hypervisor is to initialize the returned memory page, the message allowing the guest to identify the returned memory page as initialized without additional processing, and the hypervisor deferring the initializing until the guest accesses the returned memory page.