RE: [PATCH net-next 00/19] Mellanox, mlx5 sub function support

Parav Pandit
2019-11-08T15:01:39Z

> -----Original Message-----
> From: Leon Romanovsky <leon@kernel.org>
> Sent: Friday, November 8, 2019 12:20 AM
> To: Parav Pandit <parav@mellanox.com>
> Cc: alex.williamson@redhat.com; davem@davemloft.net;
> kvm@vger.kernel.org; netdev@vger.kernel.org; Saeed Mahameed
> <saeedm@mellanox.com>; kwankhede@nvidia.com; cohuck@redhat.com;
> Jiri Pirko <jiri@mellanox.com>; linux-rdma@vger.kernel.org
> Subject: Re: [PATCH net-next 00/19] Mellanox, mlx5 sub function support
>
> On Thu, Nov 07, 2019 at 08:10:45PM +0000, Parav Pandit wrote:
> > Hi Leon,
> >
> > > -----Original Message-----
> > > From: Leon Romanovsky <leon@kernel.org>
> > > Sent: Thursday, November 7, 2019 11:04 AM
> > > To: Parav Pandit <parav@mellanox.com>
> > > Cc: alex.williamson@redhat.com; davem@davemloft.net;
> > > kvm@vger.kernel.org; netdev@vger.kernel.org; Saeed Mahameed
> > > <saeedm@mellanox.com>; kwankhede@nvidia.com;
> cohuck@redhat.com; Jiri
> > > Pirko <jiri@mellanox.com>; linux-rdma@vger.kernel.org
> > > Subject: Re: [PATCH net-next 00/19] Mellanox, mlx5 sub function
> > > support
> > >
> > > On Thu, Nov 07, 2019 at 10:04:48AM -0600, Parav Pandit wrote:
> > > > Hi Dave, Jiri, Alex,
> > > >
> > >
> > > <...>
> > >
> > > > - View netdevice and (optionally) RDMA device using iproute2 tools
> > > > $ ip link show
> > > > $ rdma dev show
> > >
> > > You perfectly explained how ETH devices will be named, but what
> > > about RDMA?
> > > How will be named? I feel that rdma-core needs to be extended to
> > > support such mediated devices.
> > >
> > rdma devices are named by default using mlx_X.
> > After your persistent naming patches, I thought we have GUID based
> naming scheme which doesn't care about its underlying bus.
>
> No, it is not how it is done. RDMA persistent naming is modeled exactly as
> ETH naming, it means that we do care about bus and we don't use GUID
> unless user explicitly asked, exactly as MAC based names in ETH world.
>
> > So mdevs will be able to use current GUID based naming scheme we
> already have.
>
> Unfortunately, no.
>
> >
> > Additionally, if user prefers, mdev alias, we can extend systemd/udev to
> use mdev alias based names (like PCI bdf).
>
> It is not "Additionally", but "must".
>
Ok. So will do post this series with similar naming scheme.
Will update the cover letter to describe rdma naming too.

> > Such as,
> > rocem<alias1>
> > ibm<alias2>
> > Format is:
> > <link_layer><m><alias>
> > m -> stands for mdev device (similar to 'p' for PCI)