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Date: Tue, 18 Jul 2023 15:45:03 -0700
From: Jakub Kicinski <kuba@kernel.org>
To: David Ahern <dsahern@kernel.org>
Cc: Jason Gunthorpe <jgg@ziepe.ca>, Mina Almasry <almasrymina@google.com>,
 Andy Lutomirski <luto@kernel.org>, linux-kernel@vger.kernel.org,
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 <christian.koenig@amd.com>, "David S. Miller" <davem@davemloft.net>, Eric
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 Dangaard Brouer <hawk@kernel.org>, Ilias Apalodimas
 <ilias.apalodimas@linaro.org>, Arnd Bergmann <arnd@arndb.de>, Willem de
 Bruijn <willemdebruijn.kernel@gmail.com>, Shuah Khan <shuah@kernel.org>
Subject: Re: [RFC PATCH 00/10] Device Memory TCP
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On Tue, 18 Jul 2023 16:35:17 -0600 David Ahern wrote:
> I do not see how 1 RSS context (or more specifically a h/w Rx queue) can
> be used properly with memory from different processes (or dma-buf
> references). When the process dies, that memory needs to be flushed from
> the H/W queues. Queues with interlaced submissions make that more
> complicated.

Agreed, one process, one control path socket.

FWIW the rtnetlink use of netlink is very basic. genetlink already has
some infra which allows associate state with a user socket and cleaning
it up when the socket gets closed. This needs some improvements. A bit
of a chicken and egg problem, I can't make the improvements until there
are families making use of it, and nobody will make use of it until
it's in tree... But the basics are already in place and I can help with
building it out.

> I guess the devil is in the details; I look forward to the evolution of
> the patches.

+1