From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from lindbergh.monkeyblade.net (lindbergh.monkeyblade.net [23.128.96.19]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 552641E1D2 for ; Thu, 10 Aug 2023 16:07:37 +0000 (UTC) Received: from mail-pl1-x62e.google.com (mail-pl1-x62e.google.com [IPv6:2607:f8b0:4864:20::62e]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 3512C3583 for ; Thu, 10 Aug 2023 09:07:27 -0700 (PDT) Received: by mail-pl1-x62e.google.com with SMTP id d9443c01a7336-1bbc64f9a91so9669345ad.0 for ; Thu, 10 Aug 2023 09:07:27 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=ziepe.ca; s=google; t=1691683619; x=1692288419; h=in-reply-to:content-transfer-encoding:content-disposition :mime-version:references:message-id:subject:cc:to:from:date:from:to :cc:subject:date:message-id:reply-to; bh=Bkl7A8nIZ4dLxOcY6GpHpFtX+viPmkaZX3wq6XxPfxg=; b=JL9PB5YetmewwFt4dDybaPdzwmRNljhoEiaIvSyobmvxBnbUSrib0/OLZrInyO+/1c WxEb27kvGab0U19ny3qjovhvp4KPMhmrM2Jqtl/Sybe5g/zIKFpOOF62rMgIkHHf4UbB VKhhEHQLs4ges87nYRT9ch0zp7xExv1gT874o21HXlD6fq1w4HfWb5w6aIB4k6n17BS6 sHwCkyxjqIF/8NI5kQBcfC3SRO7xYSESm9CyKct1e2y0kTPD1OEFcZVOieF6bi0mgKVN nkDDYLgPl8A0tzyRQn+5DPmETmTTMEvWVvuuyb3zFt2rluHyUxJ0uPc6WGGARgxW4JyZ JPcQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20221208; t=1691683619; x=1692288419; h=in-reply-to:content-transfer-encoding:content-disposition :mime-version:references:message-id:subject:cc:to:from:date :x-gm-message-state:from:to:cc:subject:date:message-id:reply-to; bh=Bkl7A8nIZ4dLxOcY6GpHpFtX+viPmkaZX3wq6XxPfxg=; b=ISxAAmyGzqpft80ZRltDljmo3YUxqO4/vpbFA6sjFakjpEn+EKm8ImuHbh7T6L5TG9 OhDr4F6RZ9B8PVpYabB4wwPbV2xtVvT3WKqqPZ9Cds4+TcsX8TYHMZnTWfpxMUGJkmLO 2JCiTwTLuthkIjRObgozsweikNCda0WpYW+cv+398Ph15afBa8egFZiIS3Q5u+BFsv+w UQr79NZFIHJFjj7FcpN/iQi0FNERRVZS7AAh7ssXoYQLj65Mhu7t4eecASFwwMVBHCFc 0Fd4UQqF6fq0XaLRUnu6e01MJMhgdMN2Nz4297ConKnkTrjJMZLDyYQKSt/uSZ3PtDwP w5xQ== X-Gm-Message-State: AOJu0Yw8ekB5c+7mc6R6HuZ7mzrFEnDBmqW3lCtUkXItT1cYwmoLL5yk 9vdJPUVki6FSdlVu832/0GaqPA== X-Google-Smtp-Source: AGHT+IF4hyqWBe3EdaSGly2P8UCzQ7nDhJe1xj0NdzWbJpW3WsvHw4tGYB8oXfKwdLOgDTGQE6RMzw== X-Received: by 2002:a17:903:182:b0:1bb:ed65:5e0d with SMTP id z2-20020a170903018200b001bbed655e0dmr3656999plg.56.1691683619216; Thu, 10 Aug 2023 09:06:59 -0700 (PDT) Received: from ziepe.ca ([206.223.160.26]) by smtp.gmail.com with ESMTPSA id j16-20020a170902da9000b001b8a1a25e6asm1955107plx.128.2023.08.10.09.06.57 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Thu, 10 Aug 2023 09:06:57 -0700 (PDT) Received: from jgg by wakko with local (Exim 4.95) (envelope-from ) id 1qU8Bc-005Glp-95; Thu, 10 Aug 2023 13:06:56 -0300 Date: Thu, 10 Aug 2023 13:06:56 -0300 From: Jason Gunthorpe To: Christian =?utf-8?B?S8O2bmln?= Cc: Mina Almasry , netdev@vger.kernel.org, linux-media@vger.kernel.org, dri-devel@lists.freedesktop.org, "David S. Miller" , Eric Dumazet , Jakub Kicinski , Paolo Abeni , Jesper Dangaard Brouer , Ilias Apalodimas , Arnd Bergmann , David Ahern , Willem de Bruijn , Sumit Semwal , Hari Ramakrishnan , Dan Williams , Andy Lutomirski , stephen@networkplumber.org, sdf@google.com Subject: Re: [RFC PATCH v2 00/11] Device Memory TCP Message-ID: References: <20230810015751.3297321-1-almasrymina@google.com> <1009bd5b-d577-ca7b-8eff-192ee89ad67d@amd.com> Precedence: bulk X-Mailing-List: netdev@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: <1009bd5b-d577-ca7b-8eff-192ee89ad67d@amd.com> X-Spam-Status: No, score=-2.1 required=5.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,DKIM_VALID_EF,RCVD_IN_DNSWL_NONE, SPF_HELO_NONE,SPF_PASS autolearn=ham autolearn_force=no version=3.4.6 X-Spam-Checker-Version: SpamAssassin 3.4.6 (2021-04-09) on lindbergh.monkeyblade.net On Thu, Aug 10, 2023 at 12:29:08PM +0200, Christian König wrote: > Am 10.08.23 um 03:57 schrieb Mina Almasry: > > Changes in RFC v2: > > ------------------ > > > > The sticking point in RFC v1[1] was the dma-buf pages approach we used to > > deliver the device memory to the TCP stack. RFC v2 is a proof-of-concept > > that attempts to resolve this by implementing scatterlist support in the > > networking stack, such that we can import the dma-buf scatterlist > > directly. > > Impressive work, I didn't thought that this would be possible that "easily". > > Please note that we have considered replacing scatterlists with simple > arrays of DMA-addresses in the DMA-buf framework to avoid people trying to > access the struct page inside the scatterlist. > > It might be a good idea to push for that first before this here is finally > implemented. > > GPU drivers already convert the scatterlist used to arrays of DMA-addresses > as soon as they get them. This leaves RDMA and V4L as the other two main > users which would need to be converted. Oh that would be a nightmare for RDMA. We need a standard based way to have scalable lists of DMA addresses :( > > 2. Netlink API (Patch 1 & 2). > > How does netlink manage the lifetime of objects? And access control.. Jason