[Qemu-devel] QEMU tries to register to VFIO memory that is not RAM

[Thanos Makatos]

When configuring device pass-through via VFIO to a VM, I noticed that QEMU 
tries to register (DMA_MAP) all memory regions of a guest (not only RAM). That 
includes firmware regions like "pc.rom". Would a physical device ever need 
access to those? Am I missing something?