On Fri, 7 Aug 2020 13:59:42 +0200 Cornelia Huck <cohuck@xxxxxxxxxx> wrote: > On Wed, 05 Aug 2020 12:35:01 +0100 > Sean Mooney <smooney@xxxxxxxxxx> wrote: > > > On Wed, 2020-08-05 at 12:53 +0200, Jiri Pirko wrote: > > > Wed, Aug 05, 2020 at 11:33:38AM CEST, yan.y.zhao@xxxxxxxxx wrote: > > (...) > > > > > software_version: device driver's version. > > > > in <major>.<minor>[.bugfix] scheme, where there is no > > > > compatibility across major versions, minor versions have > > > > forward compatibility (ex. 1-> 2 is ok, 2 -> 1 is not) and > > > > bugfix version number indicates some degree of internal > > > > improvement that is not visible to the user in terms of > > > > features or compatibility, > > > > > > > > vendor specific attributes: each vendor may define different attributes > > > > device id : device id of a physical devices or mdev's parent pci device. > > > > it could be equal to pci id for pci devices > > > > aggregator: used together with mdev_type. e.g. aggregator=2 together > > > > with i915-GVTg_V5_4 means 2*1/4=1/2 of a gen9 Intel > > > > graphics device. > > > > remote_url: for a local NVMe VF, it may be configured with a remote > > > > url of a remote storage and all data is stored in the > > > > remote side specified by the remote url. > > > > ... > > just a minor not that i find ^ much more simmple to understand then > > the current proposal with self and compatiable. > > if i have well defiend attibute that i can parse and understand that allow > > me to calulate the what is and is not compatible that is likely going to > > more useful as you wont have to keep maintianing a list of other compatible > > devices every time a new sku is released. > > > > in anycase thank for actully shareing ^ as it make it simpler to reson about what > > you have previously proposed. > > So, what would be the most helpful format? A 'software_version' field > that follows the conventions outlined above, and other (possibly > optional) fields that have to match? Just to get a different perspective, I've been trying to come up with what would be useful for a very different kind of device, namely vfio-ccw. (Adding Eric to cc: for that.) software_version makes sense for everybody, so it should be a standard attribute. For the vfio-ccw type, we have only one vendor driver (vfio-ccw_IO). Given a subchannel A, we want to make sure that subchannel B has a reasonable chance of being compatible. I guess that means: - same subchannel type (I/O) - same chpid type (e.g. all FICON; I assume there are no 'mixed' setups -- Eric?) - same number of chpids? Maybe we can live without that and just inject some machine checks, I don't know. Same chpid numbers is something we cannot guarantee, especially if we want to migrate cross-CEC (to another machine.) Other possibly interesting information is not available at the subchannel level (vfio-ccw is a subchannel driver.) So, looking at a concrete subchannel on one of my machines, it would look something like the following: <common> software_version=1.0.0 type=vfio-ccw <-- would be vfio-pci on the example above <vfio-ccw specific> subchannel_type=0 <vfio-ccw_IO specific> chpid_type=0x1a chpid_mask=0xf0 <-- not sure if needed/wanted Does that make sense?
