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Subject: Re: [RFC PATCH v2 02/11] netdev: implement netlink api to bind
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To: Willem de Bruijn <willemdebruijn.kernel@gmail.com>
Cc: Jakub Kicinski <kuba@kernel.org>, Mina Almasry <almasrymina@google.com>,
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On 8/19/23 8:18 AM, Willem de Bruijn wrote:
> That may be an incentive for vendors to support per-queue
> start/stop/alloc/free. Maybe the ones that support RDMA already do?

I looked at most of the H/W RDMA in-tree kernel drivers today, and all
of them hand-off create_qp to firmware. I am really surprised by that
given that many of those drivers work with netdev. I am fairly certain
mlx5 and ConnectX 5-6, for example, can be used to achieve the
architecture we proposed at netdev [1], so I was expecting a general
queue management interface.

Between that and a skim of the providers (userspace side of it), the IB
interface may be a dead-end from the perspective of the goals here.

[1]
https://netdevconf.info/0x16/slides/34/netdev-0x16-Merging-the-Networking-Worlds-slides.pdf,
slide 14.