Re: [PATCH] RDMA/core: use rdma_cap_iw_cm() in rdma_resolve_route()

[Jason Gunthorpe <jgg@nvidia.com>]

On Wed, Sep 20, 2023 at 09:07:44AM -0400, Vitaly Mayatskikh wrote:
> On Wed, Sep 20, 2023 at 8:55 AM Jason Gunthorpe <jgg@nvidia.com> wrote:
> 
> > > > > Our driver does not support iWarp, but implements IW_CM callbacks. The patch has
> > > > > the only fix that was needed to make it work w/o a full blown iWarp.
> > >
> > > It is hard to say without having driver in-tree and seeing the result of
> > > ib_device_check_mandatory() in regards of kverbs_provider variable.
> > >
> > > Does any existing in-tree driver require the proposed change in
> > > rdma-cm?
> >
> > Yes, lets see a driver first please.
> >
> > iWarp CM is tightly tied to iWarp, I have a hard time understanding
> > how you could have the CM without supporting iWarp too.
> 
> Yes, it is coming. Not sure about the timeline, but the intent is to
> opensource the drivers. I'll defer the patch till then.
> 
> The IB driver implements ib_device_ops->iw_* ops and cq/qp/mr-related
> kverbs. This is sufficient for CM to work with the device in
> principle.

But is it iWarp?

I'm not keen on seeing people abuse iwarp stuff for some non-standards
based thing. iwarp is already in a disused state, there isn't enough
community energy there to police something non-standards based.

Jason