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=-2.3 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,USER_AGENT_SANE_1 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 4BAAEC433FF for ; Fri, 2 Aug 2019 13:35:14 +0000 (UTC) Received: from lists.gnu.org (lists.gnu.org [209.51.188.17]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id 234722073D for ; Fri, 2 Aug 2019 13:35:14 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 234722073D Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=redhat.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Received: from localhost ([::1]:34880 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.86_2) (envelope-from ) id 1htXiD-0000Io-FF for qemu-devel@archiver.kernel.org; Fri, 02 Aug 2019 09:35:13 -0400 Received: from eggs.gnu.org ([2001:470:142:3::10]:53139) by lists.gnu.org with esmtp (Exim 4.86_2) (envelope-from ) id 1htXhd-0007hX-Qo for qemu-devel@nongnu.org; Fri, 02 Aug 2019 09:34:38 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1htXhc-0006eY-Ua for qemu-devel@nongnu.org; Fri, 02 Aug 2019 09:34:37 -0400 Received: from mx1.redhat.com ([209.132.183.28]:33646) by eggs.gnu.org with esmtps (TLS1.0:DHE_RSA_AES_256_CBC_SHA1:32) (Exim 4.71) (envelope-from ) id 1htXha-0006d4-P8; Fri, 02 Aug 2019 09:34:34 -0400 Received: from smtp.corp.redhat.com (int-mx03.intmail.prod.int.phx2.redhat.com [10.5.11.13]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mx1.redhat.com (Postfix) with ESMTPS id 16EA0307D88D; Fri, 2 Aug 2019 13:34:34 +0000 (UTC) Received: from localhost.localdomain (ovpn-117-107.ams2.redhat.com [10.36.117.107]) by smtp.corp.redhat.com (Postfix) with ESMTPS id 202DE60A97; Fri, 2 Aug 2019 13:34:29 +0000 (UTC) Date: Fri, 2 Aug 2019 15:34:28 +0200 From: Kevin Wolf To: Max Reitz Message-ID: <20190802133428.GC6379@localhost.localdomain> References: <20190801173900.23851-1-mreitz@redhat.com> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline In-Reply-To: <20190801173900.23851-1-mreitz@redhat.com> User-Agent: Mutt/1.11.3 (2019-02-01) X-Scanned-By: MIMEDefang 2.79 on 10.5.11.13 X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.5.16 (mx1.redhat.com [10.5.110.48]); Fri, 02 Aug 2019 13:34:34 +0000 (UTC) Content-Transfer-Encoding: quoted-printable X-detected-operating-system: by eggs.gnu.org: GNU/Linux 2.2.x-3.x [generic] X-Received-From: 209.132.183.28 Subject: Re: [Qemu-devel] [PATCH v2 for-4.1 0/2] backup: Copy only dirty areas X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.23 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: peter.maydell@linaro.org, Vladimir Sementsov-Ogievskiy , qemu-block@nongnu.org, qemu-devel@nongnu.org, qemu-stable@nongnu.org, John Snow Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: "Qemu-devel" Am 01.08.2019 um 19:38 hat Max Reitz geschrieben: > Hi, >=20 > In a discussion with Vladimir today, we noticed that the backup job > currently is pretty broken when using copy offloading. I don=E2=80=99t= know > about you, but my local filesystem (XFS) supports copy offloading, so > the job uses it automatically. That means, that backup is broken and > has been broken for a year on my local FS. >=20 > The last working version was 2.12, so this isn=E2=80=99t a regression i= n 4.1. > We could thus justify moving it to 4.2. But I think this should really > go into 4.1, because this is not really an edge case and as far as I > know users cannot do anything to prevent the backup job from performing > copy offloading if the system and all involved block drivers support it= . > I just wonder why nobody has noticed... This sounds bad indeed. But are we already going to have an -rc4 for other reasons, or would this mean to have one only for the backup fix? Also, if you say this was broken in 4.0, Cc: qemu-stable Kevin