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[82.69.66.36]) by smtp.gmail.com with ESMTPSA id 5b1f17b1804b1-43eb613ae24sm19468475e9.40.2025.04.02.05.35.22 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Wed, 02 Apr 2025 05:35:23 -0700 (PDT) Date: Wed, 2 Apr 2025 13:35:20 +0100 From: David Laight To: Linus Torvalds Cc: Stefan Metzmacher , Jens Axboe , Pavel Begunkov , Breno Leitao , Jakub Kicinski , Christoph Hellwig , Karsten Keil , Ayush Sawal , Andrew Lunn , "David S. Miller" , Eric Dumazet , Paolo Abeni , Simon Horman , Kuniyuki Iwashima , Willem de Bruijn , David Ahern , Marcelo Ricardo Leitner , Xin Long , Neal Cardwell , Joerg Reuter , Marcel Holtmann , Johan Hedberg , Luiz Augusto von Dentz , Oliver Hartkopp , Marc Kleine-Budde , Robin van der Gracht , Oleksij Rempel , kernel@pengutronix.de, Alexander Aring , Stefan Schmidt , Miquel Raynal , Alexandra Winter , Thorsten Winkler , James Chapman , Jeremy Kerr , Matt Johnston , Matthieu Baerts , Mat Martineau , Geliang Tang , Krzysztof Kozlowski , Remi Denis-Courmont , Allison Henderson , David Howells , Marc Dionne , Wenjia Zhang , Jan Karcher , "D. Wythe" , Tony Lu , Wen Gu , Jon Maloy , Boris Pismenny , John Fastabend , Stefano Garzarella , Martin Schiller , =?UTF-8?B?QmrDtnJuIFTDtnBlbA==?= , Magnus Karlsson , Maciej Fijalkowski , Jonathan Lemon , Alexei Starovoitov , Daniel Borkmann , Jesper Dangaard Brouer , netdev@vger.kernel.org, linux-kernel@vger.kernel.org, linux-sctp@vger.kernel.org, linux-hams@vger.kernel.org, linux-bluetooth@vger.kernel.org, linux-can@vger.kernel.org, dccp@vger.kernel.org, linux-wpan@vger.kernel.org, linux-s390@vger.kernel.org, mptcp@lists.linux.dev, linux-rdma@vger.kernel.org, rds-devel@oss.oracle.com, linux-afs@lists.infradead.org, tipc-discussion@lists.sourceforge.net, virtualization@lists.linux.dev, linux-x25@vger.kernel.org, bpf@vger.kernel.org, isdn4linux@listserv.isdn4linux.de, io-uring@vger.kernel.org Subject: Re: [RFC PATCH 0/4] net/io_uring: pass a kernel pointer via optlen_t to proto[_ops].getsockopt() Message-ID: <20250402133520.40451468@pumpkin> In-Reply-To: References: X-Mailer: Claws Mail 4.1.1 (GTK 3.24.38; arm-unknown-linux-gnueabihf) Precedence: bulk X-Mailing-List: virtualization@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit On Tue, 1 Apr 2025 17:40:19 -0700 Linus Torvalds wrote: > " > > On Mon, 31 Mar 2025 at 13:11, Stefan Metzmacher wrote: > > > > But as Linus don't like 'sockptr_t' I used a different approach. > > So the sockptr_t thing has already happened. I hate it, and I think > it's ugly as hell, but it is what it is. > > I think it's a complete hack and having that "kernel or user" pointer > flag is disgusting. I have proposed a patch which replaced it with a structure. That showed up some really hacky code in IIRC io_uring. Using sockptr_t for the buffer was one thing, the generic code can't copy the buffer to/from user because code lies about the length. But using for the length is just brain-dead. That is fixed size and can be copied from/to user by the wrapper. The code bloat reduction will be significant. David