On Fri, May 31, 2019 at 05:05:26PM -0400, Michael S. Tsirkin wrote: > On Fri, May 31, 2019 at 02:29:33PM -0600, Alex Williamson wrote: > > I don't know what this frontend/backend rework would > > look like for vfio-pci, but it seems non-trivial for this one use case > > and I don't see that it adds any value outside of this use case, > > perhaps quite the opposite, it's an overly complicated interface for > > the majority of use cases so we either move to a more complicated > > interface or maintain both. Poor choices either way. > > Well put Alex this is what I meant when I said it's a useless > interface. I meant it only has a single use.
I might agree if the code needed to hide the VFIO device from the guest while keeping resources open (so it can be re-added if migration fails) is demonstrably simpler than the code that would be necessary to separate the device backend from the frontend. But I couldn't find the code that does that in this series. Is this already implemented? All I see is a qdev_unplug() call (which will close host resources) and a qdev_device_add() call (which will reopen the host device). -- Eduardo