From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-4.0 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS, URIBL_BLOCKED autolearn=no autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id A179AC433E0 for ; Tue, 14 Jul 2020 20:38:52 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 807AA2064B for ; Tue, 14 Jul 2020 20:38:52 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727043AbgGNUiv (ORCPT ); Tue, 14 Jul 2020 16:38:51 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:55998 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725945AbgGNUiv (ORCPT ); Tue, 14 Jul 2020 16:38:51 -0400 Received: from shards.monkeyblade.net (shards.monkeyblade.net [IPv6:2620:137:e000::1:9]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 993F0C061755 for ; Tue, 14 Jul 2020 13:38:51 -0700 (PDT) Received: from localhost (unknown [IPv6:2601:601:9f00:477::3d5]) (using TLSv1 with cipher AES256-SHA (256/256 bits)) (Client did not present a certificate) (Authenticated sender: davem-davemloft) by shards.monkeyblade.net (Postfix) with ESMTPSA id 3C08615E2420E; Tue, 14 Jul 2020 13:38:50 -0700 (PDT) Date: Tue, 14 Jul 2020 13:38:49 -0700 (PDT) Message-Id: <20200714.133849.786362008823993310.davem@davemloft.net> To: borisp@mellanox.com Cc: kuba@kernel.org, john.fastabend@gmail.com, daniel@iogearbox.net, tariqt@mellanox.com, netdev@vger.kernel.org Subject: Re: [PATCH] tls: add zerocopy device sendpage From: David Miller In-Reply-To: References: <9d13245f-4c0d-c377-fecf-c8f8d9eace2a@mellanox.com> <20200713155906.097a6fcd@kicinski-fedora-pc1c0hjn.dhcp.thefacebook.com> X-Mailer: Mew version 6.8 on Emacs 26.3 Mime-Version: 1.0 Content-Type: Text/Plain; charset=us-ascii Content-Transfer-Encoding: 7bit X-Greylist: Sender succeeded SMTP AUTH, not delayed by milter-greylist-4.5.12 (shards.monkeyblade.net [149.20.54.216]); Tue, 14 Jul 2020 13:38:50 -0700 (PDT) Sender: netdev-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org From: Boris Pismenny Date: Tue, 14 Jul 2020 10:31:25 +0300 > At the time, Dave objected when we presented this on the netdev conference, > and we didn't want to delay the entire series just to argue this point. It's > all a matter of timing and priorities. Now we have an ASIC that uses this API, > and I'd like to show the best possible outcome, and not the best possible given > an arbitrary limitation that avoids an error where the user does something > erroneous. It's not arbitrary, and what the user is doing is not "erroneous". Imagine a userspace fileserver using sendpage, other users in the system can write to the files while the fileserver sends it off to a client. And that's perfectly legitimate and fine. We get the IP checksums correct, everything works. And, therefore, if TLS is used, the signatures should be correct too. And I'm also happy to hear that from the very start I was against an implementation that would knowingly send incorrect signatures. I'm not moving on this point, sorry. Correctness over performance.