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=-10.3 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,MENTIONS_GIT_HOSTING, NICE_REPLY_A,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_AGENT_SANE_1 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 5F69FC43463 for ; Mon, 21 Sep 2020 06:25:32 +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 9DA9D20735 for ; Mon, 21 Sep 2020 06:25:31 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 9DA9D20735 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=ispras.ru Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Received: from localhost ([::1]:57498 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1kKFGS-0004Uq-RZ for qemu-devel@archiver.kernel.org; Mon, 21 Sep 2020 02:25:28 -0400 Received: from eggs.gnu.org ([2001:470:142:3::10]:50346) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1kKFFW-000457-8T for qemu-devel@nongnu.org; Mon, 21 Sep 2020 02:24:30 -0400 Received: from mail.ispras.ru ([83.149.199.84]:34166) by eggs.gnu.org with esmtps (TLS1.2:DHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1kKFFT-0002b6-TY for qemu-devel@nongnu.org; Mon, 21 Sep 2020 02:24:30 -0400 Received: from [192.168.0.183] (unknown [62.118.151.149]) by mail.ispras.ru (Postfix) with ESMTPSA id 74C6440D403E; Mon, 21 Sep 2020 06:24:24 +0000 (UTC) Subject: Re: [PATCH v4 00/15] Reverse debugging From: Pavel Dovgalyuk To: Paolo Bonzini , qemu-devel@nongnu.org References: <160006358590.31457.16757371597343007847.stgit@pasha-ThinkPad-X280> <70d75fb9-fb91-8574-2f69-f730969a61ba@ispras.ru> Message-ID: <38bc996d-b7e6-e89e-f166-2623b0ce554e@ispras.ru> Date: Mon, 21 Sep 2020 09:24:24 +0300 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: <70d75fb9-fb91-8574-2f69-f730969a61ba@ispras.ru> Content-Type: text/plain; charset=utf-8; format=flowed Content-Language: en-US Content-Transfer-Encoding: 8bit Received-SPF: pass client-ip=83.149.199.84; envelope-from=pavel.dovgalyuk@ispras.ru; helo=mail.ispras.ru X-detected-operating-system: by eggs.gnu.org: First seen = 2020/09/21 02:03:38 X-ACL-Warn: Detected OS = Linux 3.11 and newer [fuzzy] X-Spam_score_int: -18 X-Spam_score: -1.9 X-Spam_bar: - X-Spam_report: (-1.9 / 5.0 requ) BAYES_00=-1.9, NICE_REPLY_A=-0.001, 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: kwolf@redhat.com, wrampazz@redhat.com, ehabkost@redhat.com, alex.bennee@linaro.org, mtosatti@redhat.com, armbru@redhat.com, mreitz@redhat.com, stefanha@redhat.com, crosa@redhat.com, philmd@redhat.com, zhiwei_liu@c-sky.com, rth@twiddle.net Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: "Qemu-devel" On 21.09.2020 09:03, Pavel Dovgalyuk wrote: > On 20.09.2020 10:58, Paolo Bonzini wrote: >> On 14/09/20 08:06, Pavel Dovgalyuk wrote: >>> GDB remote protocol supports reverse debugging of the targets. >>> It includes 'reverse step' and 'reverse continue' operations. >>> The first one finds the previous step of the execution, >>> and the second one is intended to stop at the last breakpoint that >>> would happen when the program is executed normally. >>> >>> Reverse debugging is possible in the replay mode, when at least >>> one snapshot was created at the record or replay phase. >>> QEMU can use these snapshots for travelling back in time with GDB. >> >> I had queued this, it is a very nice patch series.  Unfortunately, the >> tests failed on gitlab: >> >> https://gitlab.com/bonzini/qemu/-/jobs/745795080 > > There is a strange thing in your environment: > > 15:49:41 INFO | Downloading/preparing boot image > 15:49:42 INFO | Running '/builds/bonzini/qemu/build/qemu-img create -f > qcow2 -b > /builds/bonzini/qemu/avocado-cache/by_location/d2a8d6b607afec50de14560c064f34ffd99836b2/Fedora-Cloud-Base-31-1.9.x86_64.qcow2 > /var/tmp/avocado_tj2janfx/avocado_job_ys7ueohj/04-tests_acceptance_boot_linux.py_BootLinuxX8664.test_pc_q35_kvm/Fedora-Cloud-Base-31-1.9.x86_64-d1ac1224.qcow2' > > > > It downloads boot image, but there is no such requirement in the test. > And all this stuff consumes most of the time for the test. Sorry, that was ok. It was the output from the previous test. For reverse debugging there was a timeout on reading from the socket: result = self._socket.recv(REMOTE_MAX_PACKET_SIZE) Do you have any hint how to debug such a failure in this environment? Pavel Dovgalyuk