Re: [virtio-comment] [PATCH v10 00/10] Introduce device group and device management

["Michael S. Tsirkin" <mst@redhat.com>]

On Mon, Mar 06, 2023 at 01:29:30PM +0100, Jiri Pirko wrote:
> Thu, Mar 02, 2023 at 02:04:48PM CET, mst@redhat.com wrote:
> 
> [...]
> 
> >
> >TODO (maybe?) - probably ok to defer until this part is upstream:
> >
> >	Add "all members" member id.
> >
> >	Add commands for MSI, feature discovery.
> >
> >	Add commands for transport vq.
> >
> >
> >My intent is to try and support both SR-IOV and SIOV
> >usecases with the same structure and maybe even the same
> >VQ.
> 
> Sorry to be late to the party, I'm trying to catch up. Is it common to
> have cover letter for features this brief? I mean, from the cover
> letter, I'm totally unable to understand what you are introducing here.
> 
> Could you elaborate about what you are aiming to achive with this?
> Could you shed some usecases perhaps?
> 
> I have to be missing something obvious, but I don't get why any notion
> of SR-IOV could be beneficial for virtio.
> 

Good point, I'll add a bit of motivation.

For SR-IOV, it is not unusual for PFs to excercise control over VFs.
There is interest in the community to include an interface to allow this
in the virtio spec, when the PF is a virtio device.  This is what this
patch does.




> >
> >For example, it might make sense to split creating/destroying
> >SIOV devices from the transport passing data from the guest - the
> >driver would then not negotiate VIRTIO_F_SR_IOV (which
> >then means auto-provisioning).
> >
> >This is out of RFC, since we have two commands which are useful
> >to discover supported group types (ATM can be none or SR-IOV).
> >
> >
> >Michael S. Tsirkin (10):
> >  virtio: document forward compatibility guarantees
> >  admin: introduce device group and related concepts
> >  admin: introduce group administration commands
> >  admin: introduce virtio admin virtqueues
> >  pci: add admin vq registers to virtio over pci
> >  mmio: document ADMIN_VQ as reserved
> >  ccw: document ADMIN_VQ as reserved
> >  admin: command list discovery
> >  admin: conformance clauses
> >  ccw: document more reserved features
> >
> > admin.tex        | 540 +++++++++++++++++++++++++++++++++++++++++++++++
> > content.tex      | 112 +++++++++-
> > introduction.tex |   3 +
> > 3 files changed, 653 insertions(+), 2 deletions(-)
> > create mode 100644 admin.tex
> >
> >-- 
> >MST
> >
> >
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