On 17/12/19 17:18, Alex Williamson wrote: >> >> Alex, if you are OK we'll work on such interface and move kvmgt to use it. >> After it's accepted, we can also mark pages dirty through this new interface >> in Kirti's dirty page tracking series. > I'm not sure what you're asking for, is it an interface for the host > CPU to read/write the memory backing of a mapped IOVA range without > pinning pages? That seems like something like that would make sense for > an emulation model where a page does not need to be pinned for physical > DMA. If you're asking more for an interface that understands the > userspace driver is a VM (ie. implied using a _guest postfix on the > function name) and knows about GPA mappings beyond the windows directly > mapped for device access, I'd not look fondly on such a request. No, it would definitely be the former, using IOVAs to access guest memory---kvmgt is currently doing the latter by calling into KVM, and I'm not really fond of that either. Paolo
