On Mon, Jan 20, 2025 at 09:22:50PM +1100, Alexey Kardashevskiy wrote: > > It is still uncertain how to implement the private MMIO. Our assumption > > is the private MMIO would also create a memory region with > > guest_memfd-like backend. Its mr->ram is true and should be managed by > > RamdDiscardManager which can skip doing DMA_MAP in VFIO's region_add > > listener. > > My current working approach is to leave it as is in QEMU and VFIO.
Agreed. Setting ram=true to even private MMIO sounds hackish, at least currently QEMU heavily rely on that flag for any possible direct accesses. E.g., in memory_access_is_direct(). -- Peter Xu
