Re: [PATCH for-next 06/10] rdma: Set physical MTU for query_port function

[Leon Romanovsky <leon@kernel.org>]

On Thu, Apr 08, 2021 at 08:06:46AM -0400, Dennis Dalessandro wrote:
> On 4/1/2021 4:42 AM, Leon Romanovsky wrote:
> > On Mon, Mar 29, 2021 at 09:54:12AM -0400, dennis.dalessandro@cornelisnetworks.com wrote:
> > > From: Kaike Wan <kaike.wan@intel.com>
> > > 
> > > This is a follow on patch to add a phys_mtu field to the
> > > ib_port_attr structure to indicate the maximum physical MTU
> > > the underlying device supports.
> > > 
> > > Extends the following:
> > > commit 6d72344cf6c4 ("IB/ipoib: Increase ipoib Datagram mode MTU's upper limit")
> > > 
> > > Reviewed-by: Mike Marciniszyn <mike.marciniszyn@cornelisnetworks.com>
> > > Signed-off-by: Kaike Wan <kaike.wan@intel.com>
> > > Signed-off-by: Dennis Dalessandro <dennis.dalessandro@cornelisnetworks.com>
> > > ---
> > >   drivers/infiniband/hw/bnxt_re/ib_verbs.c        |  1 +
> > >   drivers/infiniband/hw/cxgb4/provider.c          |  1 +
> > >   drivers/infiniband/hw/efa/efa_verbs.c           |  1 +
> > >   drivers/infiniband/hw/hns/hns_roce_main.c       |  1 +
> > >   drivers/infiniband/hw/i40iw/i40iw_verbs.c       |  1 +
> > >   drivers/infiniband/hw/mlx4/main.c               |  1 +
> > >   drivers/infiniband/hw/mlx5/mad.c                |  1 +
> > >   drivers/infiniband/hw/mlx5/main.c               |  2 ++
> > >   drivers/infiniband/hw/mthca/mthca_provider.c    |  1 +
> > >   drivers/infiniband/hw/ocrdma/ocrdma_verbs.c     |  1 +
> > >   drivers/infiniband/hw/qib/qib_verbs.c           |  1 +
> > >   drivers/infiniband/hw/usnic/usnic_ib_verbs.c    |  1 +
> > >   drivers/infiniband/hw/vmw_pvrdma/pvrdma_verbs.c |  1 +
> > >   drivers/infiniband/sw/siw/siw_verbs.c           |  1 +
> > >   drivers/infiniband/ulp/ipoib/ipoib_main.c       |  2 +-
> > >   include/rdma/ib_verbs.h                         | 17 -----------------
> > >   16 files changed, 16 insertions(+), 18 deletions(-)
> > 
> > But why? What will it give us that almost all drivers have same
> > props->phys_mtu = ib_mtu_enum_to_int(props->max_mtu); line?
> > 
> 
> Almost is not all. Alternative idea to convey this? Seemed like a sensible
> thing to at least have support for but open to other approaches.

What about leave it as is? 

I'm struggling to get the rationale behind this patch., the code already works
and set the phys_mtu correctly, isn't it?

Thanks

> 
> -Denny