A hypervisor receives a notification from a guest operating system (OS) of a virtual machine (VM), where the notification indicates a guest OS access of a memory address associated with a device slot of a communication bus, where the device slot is unavailable to the guest OS; maps, in a page table of the hypervisor, a page table entry for a memory configuration space of the device slot to the memory address, where the page table entry indicates that the configuration space is available to the guest OS; identifies an additional device slot associated with the communication bus; and maps, in the page table, an additional page table entry for an additional memory configuration space of the additional device slot to an additional memory address, where the additional page table entry indicates that the additional configuration space is available to the guest OS.