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Date: Mon, 10 Jul 2023 21:59:06 -0700
From: Jakub Kicinski <kuba@kernel.org>
To: Christoph Hellwig <hch@lst.de>
Cc: Jason Gunthorpe <jgg@ziepe.ca>, Mina Almasry <almasrymina@google.com>,
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On Tue, 11 Jul 2023 06:27:08 +0200 Christoph Hellwig wrote:
> Not going to comment on the rest of this as it seems bat shit crazy
> hacks for out of tree junk.  Why is anyone even wasting time on this?

Noob question - how does RDMA integrate with the out of tree junk?
AFAIU it's possible to run the "in-tree" RDMA stack and get "GPU
direct".

Both Jonathan in the past (Meta) and now Mina (Google) are trying 
to move the needle and at least feed the GPUs over TCP, instead of
patented, proprietary and closed RDMA transports.