On 10/26/18, Sunil Kovvuri <sunil.kovvuri@xxxxxxxxx> wrote: > On Fri, Oct 26, 2018 at 6:24 PM Arnd Bergmann <arnd@xxxxxxxx> wrote: >> >> I see this has been applied, but I'd still like to understand better how >> the >> configuration interface is expected to work once the driver is complete. >> >> In particular, so far the interfaces all assume that configuration is >> done through the mailbox between PCI devices, which could be done >> from a virtual machine kernel with access to PCI, or through the use >> of VFIO from a user application. >> >> Is that the only method of configuring it that you support, or will there >> also be a devlink based interface or something like that to configure >> the aspects of a virtual device that should not be accessible to the >> VF itself? >> > > > As of now it's only mbox based configuration that is supported. Ok, thanks for the clarification. Does this mean that you intend to have user space tools that use the mbox based interface on VFIO devices to perform configuration for virtual network devices, or just that the configuration interface is something that needs to be designed later? I fear that setting a precedent of using the mbox for user-level configuration management would mean that we would have to treat each of these interfaces as an ABI, which in turn requires much deeper review as well as raising the fundamental question on how this should be done across drivers. The mailbox interface seem inherently nonportable to other hardware here, which is a significant downside. Arnd