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=-6.1 required=3.0 tests=BAYES_00,DKIM_INVALID, DKIM_SIGNED,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,NICE_REPLY_A, 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 1C1D2C433F7 for ; Mon, 27 Jul 2020 14:42:48 +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 E06DE20714 for ; Mon, 27 Jul 2020 14:42:47 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=fail reason="signature verification failed" (1024-bit key) header.d=redhat.com header.i=@redhat.com header.b="GLmctj0n" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org E06DE20714 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]:40766 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1k04L1-00024v-5M for qemu-devel@archiver.kernel.org; Mon, 27 Jul 2020 10:42:47 -0400 Received: from eggs.gnu.org ([2001:470:142:3::10]:54626) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1k04KE-0000jH-7W for qemu-devel@nongnu.org; Mon, 27 Jul 2020 10:41:58 -0400 Received: from us-smtp-delivery-1.mimecast.com ([205.139.110.120]:54004 helo=us-smtp-1.mimecast.com) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_CBC_SHA1:256) (Exim 4.90_1) (envelope-from ) id 1k04KB-0002aR-Re for qemu-devel@nongnu.org; Mon, 27 Jul 2020 10:41:57 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1595860915; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=aahIWJN6bGY0QOATwBA6ZjwznaDmfE/SoQBCKs0NKug=; b=GLmctj0nmusYd12/cUAhsE3KLapy2+Wty28T03R3NMq3aaKzj+MPziSe5Wv3AXLauV60JF h0o+dBWbnN81c9zgQLyCdJHT3LUbKt/hbIjKhfMl1jPMt/wJ778PDyKH2soklVMKnP+KeN 3jEVnaf+NgFJOU2q7FzzbMslfHUKxXg= Received: from mimecast-mx01.redhat.com (mimecast-mx01.redhat.com [209.132.183.4]) (Using TLS) by relay.mimecast.com with ESMTP id us-mta-376-uVWEZbg4N7Weo_Vvjj33SQ-1; Mon, 27 Jul 2020 10:41:51 -0400 X-MC-Unique: uVWEZbg4N7Weo_Vvjj33SQ-1 Received: from smtp.corp.redhat.com (int-mx06.intmail.prod.int.phx2.redhat.com [10.5.11.16]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id ED4C8106B245; Mon, 27 Jul 2020 14:41:50 +0000 (UTC) Received: from [10.3.113.26] (ovpn-113-26.phx2.redhat.com [10.3.113.26]) by smtp.corp.redhat.com (Postfix) with ESMTPS id 7C05361463; Mon, 27 Jul 2020 14:41:50 +0000 (UTC) Subject: Re: [PATCH 2/2] qemu-iotests: Test convert to qcow2 compressed to NBD To: Nir Soffer References: <20200726152532.256261-1-nsoffer@redhat.com> <20200726152532.256261-3-nsoffer@redhat.com> From: Eric Blake Organization: Red Hat, Inc. Message-ID: <5e87add3-57ed-1c57-4ea3-07a77cda3882@redhat.com> Date: Mon, 27 Jul 2020 09:41:49 -0500 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:68.0) Gecko/20100101 Thunderbird/68.10.0 MIME-Version: 1.0 In-Reply-To: Content-Language: en-US X-Scanned-By: MIMEDefang 2.79 on 10.5.11.16 X-Mimecast-Spam-Score: 0 X-Mimecast-Originator: redhat.com Content-Type: text/plain; charset=utf-8; format=flowed Content-Transfer-Encoding: 7bit Received-SPF: pass client-ip=205.139.110.120; envelope-from=eblake@redhat.com; helo=us-smtp-1.mimecast.com X-detected-operating-system: by eggs.gnu.org: First seen = 2020/07/27 01:44:14 X-ACL-Warn: Detected OS = Linux 2.2.x-3.x [generic] [fuzzy] X-Spam_score_int: -40 X-Spam_score: -4.1 X-Spam_bar: ---- X-Spam_report: (-4.1 / 5.0 requ) BAYES_00=-1.9, DKIMWL_WL_HIGH=-1, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, DKIM_VALID_EF=-0.1, RCVD_IN_DNSWL_NONE=-0.0001, RCVD_IN_MSPIKE_H2=-1, SPF_HELO_NONE=0.001, SPF_PASS=-0.001 autolearn=ham autolearn_force=no X-Spam_action: no action 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: QEMU Developers , Kevin Wolf , qemu-block , Nir Soffer , Max Reitz Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: "Qemu-devel" On 7/27/20 9:35 AM, Nir Soffer wrote: >> I guess it's okay that you don't create a real tar file here, but >> listing the commands to create it (even as a comment) is better than >> just saying "trust me". And it doesn't seem like that much more work - >> it looks like the key to your test is that you created a tar file >> containing two files, where the first file was less than 512 bytes and >> the second file is your target destination that you will be rewriting. > > The real code is more complicated, something like: > > offset = tar.fileobj.tell() + BLOCK_SIZE > > with open(tar.name, "r+") as f: > f.truncate(offset + measure["required"]) > > convert_image(image, tar.name, offset) > > check = check_image(tar.name, offset) > size = check["image-end-offset"] > > member = tarfile.TarInfo(name) > member.size = size > tar.addfile(member) > > tar_size = offset + round_up(size) > > tar.fileobj.seek(tar_size) > with open(tar.name, "r+") as f: > f.truncate(tar_size) > > I'm not sure it helps qemu developers working on these tests. The closer the iotest is to reality, the more likely it will serve as a good regression test. Cutting corners risks a test that passes in isolation even when we've done something that breaks the overall process in one of the corners you cut. >> >> At any rate, given the urgency of getting pull requests for -rc2 in >> before slamming Peter tomorrow, I'll probably try to touch up the issues >> Max pointed out and queue it today. > > Thanks Max and Eric. > > Should I post a fixed version later today? A v2 would be helpful. -- Eric Blake, Principal Software Engineer Red Hat, Inc. +1-919-301-3226 Virtualization: qemu.org | libvirt.org