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=-8.3 required=3.0 tests=BAYES_00,DKIM_INVALID, DKIM_SIGNED,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI, NICE_REPLY_A,SPF_HELO_NONE,SPF_PASS,USER_AGENT_SANE_1 autolearn=unavailable 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 119A9C433E0 for ; Tue, 14 Jul 2020 14:36:42 +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 CE1192067D for ; Tue, 14 Jul 2020 14:36:41 +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="f4NFdUpB" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org CE1192067D 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]:43050 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1jvM2z-0004Y4-3K for qemu-devel@archiver.kernel.org; Tue, 14 Jul 2020 10:36:41 -0400 Received: from eggs.gnu.org ([2001:470:142:3::10]:50472) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1jvM2B-0003wp-VU for qemu-devel@nongnu.org; Tue, 14 Jul 2020 10:35:51 -0400 Received: from us-smtp-1.mimecast.com ([205.139.110.61]:53955 helo=us-smtp-delivery-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 1jvM2A-0001EW-CQ for qemu-devel@nongnu.org; Tue, 14 Jul 2020 10:35:51 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1594737349; 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:openpgp:openpgp; bh=rYWocoJiBBXQsA+vaSo937rP5rkuZue+Rsy3iqOtFuQ=; b=f4NFdUpB/P3OhHUOpdKgmkWxv/wIljSmZRGYYYNdJCh67Nm6SDbBbCup8d4Xa+FGGtc7Rh f4mEp1ldhQmwV5A2/RNTx8P8H6GwfbIGbpAmCW8g4/g7CX5K6wbCx6H/IrR+fDoxYfQHEF st9eczRxcvNDsORYeQhk4iarpK0Jc/Y= 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-48-niR0eWUZPp6xyfSSio6SRw-1; Tue, 14 Jul 2020 10:35:47 -0400 X-MC-Unique: niR0eWUZPp6xyfSSio6SRw-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 E48CF107B7ED; Tue, 14 Jul 2020 14:35:40 +0000 (UTC) Received: from thuth.remote.csb (ovpn-112-11.ams2.redhat.com [10.36.112.11]) by smtp.corp.redhat.com (Postfix) with ESMTPS id 8A0EC5C679; Tue, 14 Jul 2020 14:35:29 +0000 (UTC) Subject: Re: migration: broken snapshot saves appear on s390 when small fields in migration stream removed To: Claudio Fontana , Paolo Bonzini , Juan Quintela , "Dr. David Alan Gilbert" , Kevin Wolf , Max Reitz References: <8bbafdec-836d-b7de-cab8-7a325b6e238d@suse.de> <55c406cd-b9ca-4e9b-0acd-d33cfe2a70e3@redhat.com> From: Thomas Huth Openpgp: preference=signencrypt Message-ID: <8125b1ff-373a-aadc-eccf-27c567007a27@redhat.com> Date: Tue, 14 Jul 2020 16:35:27 +0200 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:60.0) Gecko/20100101 Thunderbird/60.9.0 MIME-Version: 1.0 In-Reply-To: Content-Language: en-US X-Scanned-By: MIMEDefang 2.79 on 10.5.11.16 Authentication-Results: relay.mimecast.com; auth=pass smtp.auth=CUSA124A263 smtp.mailfrom=thuth@redhat.com X-Mimecast-Spam-Score: 0 X-Mimecast-Originator: redhat.com Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 7bit Received-SPF: pass client-ip=205.139.110.61; envelope-from=thuth@redhat.com; helo=us-smtp-delivery-1.mimecast.com X-detected-operating-system: by eggs.gnu.org: First seen = 2020/07/14 03:57:32 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: "Jason J. Herne" , Fam Zheng , Liang Yan , Peter Maydell , Cornelia Huck , qemu-devel , Stefan Hajnoczi Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: "Qemu-devel" On 14/07/2020 16.29, Claudio Fontana wrote: > Hello, > > I have some tiny progress in narrowing down this issue, possibly a qcow2 issue, still unclear, > but involving Kevin Wolf and Max Reitz. > > > The reproducer again: > >> --------------------------------------------cut------------------------------------------- >> diff --git a/cpus.c b/cpus.c >> index 41d1c5099f..443b88697a 100644 >> --- a/cpus.c >> +++ b/cpus.c >> @@ -643,7 +643,7 @@ static void qemu_account_warp_timer(void) >> >> static bool icount_state_needed(void *opaque) >> { >> - return use_icount; >> + return 0; >> } >> >> static bool warp_timer_state_needed(void *opaque) >> --------------------------------------------cut------------------------------------------- > > This issue for now appears on s390 only: > > On s390 hardware, test 267 fails (both kvm and tcg) in the qcow2 backing file part, with broken migration stream data in the s390-skeys vmsave (old style). [...] > If someone has a good idea let me know - first attempts to reproduce on x86 failed, but maybe more work could lead to it. Two questions: 1) Can you also reproduce the issue manually, without running iotest 267? ... I tried, but so far I failed. 2) Since all the information so far sounds like the problem could be elsewhere in the code, and the skeys just catch it by accident ... have you tried running with valgrind? Maybe it catches something useful? Thomas