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=-6.0 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,MENTIONS_GIT_HOSTING,SPF_PASS autolearn=ham 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 F3411C10F12 for ; Wed, 17 Apr 2019 07:56:43 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id C446D20872 for ; Wed, 17 Apr 2019 07:56:43 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1731242AbfDQH4m convert rfc822-to-8bit (ORCPT ); Wed, 17 Apr 2019 03:56:42 -0400 Received: from outbound.smtp.vt.edu ([198.82.183.121]:58906 "EHLO omr2.cc.vt.edu" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1731041AbfDQH4l (ORCPT ); Wed, 17 Apr 2019 03:56:41 -0400 Received: from mr4.cc.vt.edu (mr4.cc.ipv6.vt.edu [IPv6:2607:b400:92:8300:0:7b:e2b1:6a29]) by omr2.cc.vt.edu (8.14.4/8.14.4) with ESMTP id x3H7uf2M007492 for ; Wed, 17 Apr 2019 03:56:41 -0400 Received: from mail-qk1-f197.google.com (mail-qk1-f197.google.com [209.85.222.197]) by mr4.cc.vt.edu (8.14.7/8.14.7) with ESMTP id x3H7uZal006486 for ; Wed, 17 Apr 2019 03:56:41 -0400 Received: by mail-qk1-f197.google.com with SMTP id a188so20194161qkf.0 for ; Wed, 17 Apr 2019 00:56:40 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:sender:from:to:cc:subject:in-reply-to:references :mime-version:content-transfer-encoding:date:message-id; bh=XRal/KDUMxotBEJcVsOP5tkbeKLtAGY+Cmt6EWYQpMM=; b=jbz731YqMsZjunrs3nxcXYyIPuWij+QN7J6OLvurUwJQ/PmmWzxTRS6hbLfTmBo0/w 3TugCpdNpjyDO31oan4n5I1e8iUjuN9HahpWI4jVAR6G0GszNgeIzVy5qz6Lyz+ATkX6 GxcdedRdCP4F/ss/X/XdOHclPdoCgW8xJranTY9vdGPyj3ZcyvTiKh2HFR8XyaJQhaJB 79O0rPnF1xUAfJ+9EeRNeBJWz+QWtLewHdcgy9+vh9KOu7vaDyEw5H3xQoQuiHd6UYYt TlqYGN6TsVwjcI43BHjNwTvpiEPCXzDIiQdo/mwbzOI6p2uOBsK+WetZjuNzmmn+o9Vq 5vdg== X-Gm-Message-State: APjAAAVt6UJAlJvyn00PSg2ulX1LxuWMc1z52n2M+oeYIZQIIEP4ga3I Yv72fp2icvZJPTJO8ziAypLaIAVvl4ViTtnkX1VcBDEItLRvtEDaWgHGHeWt1sh8hq8kacSAhM3 3WmLKMkMaLnSm73+vXaapY/MUUPBHePufjVQ= X-Received: by 2002:a0c:897b:: with SMTP id 56mr69182567qvq.55.1555487795564; Wed, 17 Apr 2019 00:56:35 -0700 (PDT) X-Google-Smtp-Source: APXvYqx3ecN7jlhMZcM6t9DP1Pb6KVPvEg1Z5z9gv4RNYB7Cf+vCWGvu0HZ0lbB759a1mHlUIjeVrA== X-Received: by 2002:a0c:897b:: with SMTP id 56mr69182550qvq.55.1555487795257; Wed, 17 Apr 2019 00:56:35 -0700 (PDT) Received: from turing-police ([2601:5c0:c001:4341::1a7]) by smtp.gmail.com with ESMTPSA id y34sm35037616qta.96.2019.04.17.00.56.33 (version=TLS1_2 cipher=ECDHE-RSA-CHACHA20-POLY1305 bits=256/256); Wed, 17 Apr 2019 00:56:34 -0700 (PDT) From: "Valdis Kl=?utf-8?Q?=c4=93?=tnieks" X-Google-Original-From: "Valdis Kl=?utf-8?Q?=c4=93?=tnieks" X-Mailer: exmh version 2.9.0 11/07/2018 with nmh-1.7+dev To: =?utf-8?Q?=421=430=448=430?= =?utf-8?Q?_=41A=43E=432=442=443=43D=435=43D=43A=43E?= , Alexander Viro cc: kernelnewbies@kernelnewbies.org, linux-fsdevel@vger.kernel.org, linux-kernel@vger.kernel.org Subject: Re: Need advice about do we need this if condition In-reply-to: References: Mime-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 8BIT Date: Wed, 17 Apr 2019 03:56:33 -0400 Message-ID: <19402.1555487793@turing-police> Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Wed, 17 Apr 2019 08:25:22 +0300 (Adding Al Viro and the linux-fsdevel lists, as at the very least, the manpage for the syscall needs some clarification...) > hello I am trying to fix https://bugzilla.kernel.org/show_bug.cgi?id=202935 So - convince us that it's in fact a "bug" and not a restriction. > I found cause > https://github.com/torvalds/linux/blob/master/fs/cifs/cifsfs.c#L1076 not > sure is it correct to remove such condition ? Does the CIFS protocol support copying from a file to another location in the same file? Was it intended to work on *any* filesystem? (For that matter, the manpage for the syscall is unclear on whether having both file descriptors open on the same file is OK or not - for bonus ambiguity points, there's exactly zero discussion of what happens if source and destination overlap destructively).