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[209.85.208.52]) by smtp.gmail.com with ESMTPSA id bi23-20020a170906a25700b009079442dd11sm1485772ejb.154.2023.03.14.12.17.00 for (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Tue, 14 Mar 2023 12:17:00 -0700 (PDT) Received: by mail-ed1-f52.google.com with SMTP id x3so66280079edb.10 for ; Tue, 14 Mar 2023 12:17:00 -0700 (PDT) X-Received: by 2002:a17:907:2069:b0:8af:4963:fb08 with SMTP id qp9-20020a170907206900b008af4963fb08mr1869330ejb.15.1678821000656; Tue, 14 Mar 2023 12:10:00 -0700 (PDT) MIME-Version: 1.0 References: <20230308165251.2078898-1-dhowells@redhat.com> <20230308165251.2078898-4-dhowells@redhat.com> <3761465.1678818404@warthog.procyon.org.uk> In-Reply-To: From: Linus Torvalds Date: Tue, 14 Mar 2023 12:09:43 -0700 X-Gmail-Original-Message-ID: Message-ID: Subject: Re: [PATCH v17 03/14] shmem: Implement splice-read To: David Howells Cc: Matthew Wilcox , Jens Axboe , Al Viro , Christoph Hellwig , Jan Kara , Jeff Layton , David Hildenbrand , Jason Gunthorpe , Logan Gunthorpe , Hillf Danton , linux-fsdevel@vger.kernel.org, linux-block@vger.kernel.org, linux-kernel@vger.kernel.org, linux-mm@kvack.org, Daniel Golle , Guenter Roeck , Christoph Hellwig , John Hubbard , Hugh Dickins Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable X-Rspam-User: X-Rspamd-Server: rspam03 X-Stat-Signature: 9qf4zt7681e141ozk69io3ikmfwapuaa X-Rspamd-Queue-Id: 9004A100011 X-HE-Tag: 1678821422-7318 X-HE-Meta: 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 4WVFyEKB 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 X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: On Tue, Mar 14, 2023 at 12:07=E2=80=AFPM Linus Torvalds wrote: > > Maybe we can do /dev/null some day and actually have a common case for th= ose. /dev/zero, I mean. We already do splice to /dev/null (and splicing from /dev/null isn't interesting ;) Linus