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=-8.1 required=3.0 tests=DKIM_INVALID,DKIM_SIGNED, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_HELO_NONE,SPF_PASS,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 0DA34CA90AF for ; Wed, 13 May 2020 09:48:32 +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 CF34920769 for ; Wed, 13 May 2020 09:48:31 +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="ISRlpcrH" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org CF34920769 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]:33718 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1jYo06-0003lA-V0 for qemu-devel@archiver.kernel.org; Wed, 13 May 2020 05:48:30 -0400 Received: from eggs.gnu.org ([2001:470:142:3::10]:43724) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1jYnyr-00032Q-IO for qemu-devel@nongnu.org; Wed, 13 May 2020 05:47:13 -0400 Received: from us-smtp-1.mimecast.com ([207.211.31.81]:42674 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 1jYnyq-00027x-9x for qemu-devel@nongnu.org; Wed, 13 May 2020 05:47:12 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1589363231; 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: in-reply-to:in-reply-to:references:references; bh=icHSjLUhPV4QCazSWdI9Y8/NTLGaUe3IsfXiGpTMN98=; b=ISRlpcrHzEo3/FlpvtKy0RtgHt2mq2RxYtjjsVJmM1vAcL1D6pWppyxuFBCEADr7NhhXd7 QeBS8Q7P+0LcQ00Cxgj1ad7V2pOA/mAzqyK+leyyw+jS5P2YRgoNnLG0NegtBs+yIOE1jD tgKrzDBCX2wUrxyDytPcs5LtUnScWVg= 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-371--uTwej90PIqSCwrdwW_cMQ-1; Wed, 13 May 2020 05:47:07 -0400 X-MC-Unique: -uTwej90PIqSCwrdwW_cMQ-1 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 mimecast-mx01.redhat.com (Postfix) with ESMTPS id 6EA568018AC; Wed, 13 May 2020 09:47:06 +0000 (UTC) Received: from work-vm (ovpn-115-30.ams2.redhat.com [10.36.115.30]) by smtp.corp.redhat.com (Postfix) with ESMTPS id 57E2C7D94B; Wed, 13 May 2020 09:47:05 +0000 (UTC) Date: Wed, 13 May 2020 10:47:02 +0100 From: "Dr. David Alan Gilbert" To: Lukas Straub Subject: Re: [PATCH 2/6] migration/colo.c: Use cpu_synchronize_all_states() Message-ID: <20200513094702.GC3225@work-vm> References: <9675031ce557b73ebd10e7bd20ebbf57f30b177c.1589193382.git.lukasstraub2@web.de> MIME-Version: 1.0 In-Reply-To: <9675031ce557b73ebd10e7bd20ebbf57f30b177c.1589193382.git.lukasstraub2@web.de> User-Agent: Mutt/1.13.4 (2020-02-15) X-Scanned-By: MIMEDefang 2.79 on 10.5.11.13 X-Mimecast-Spam-Score: 0 X-Mimecast-Originator: redhat.com Content-Type: text/plain; charset=us-ascii Content-Disposition: inline Received-SPF: pass client-ip=207.211.31.81; envelope-from=dgilbert@redhat.com; helo=us-smtp-delivery-1.mimecast.com X-detected-operating-system: by eggs.gnu.org: First seen = 2020/05/13 04:17:42 X-ACL-Warn: Detected OS = Linux 2.2.x-3.x [generic] [fuzzy] X-Spam_score_int: -20 X-Spam_score: -2.1 X-Spam_bar: -- X-Spam_report: (-2.1 / 5.0 requ) BAYES_00=-1.9, DKIMWL_WL_HIGH=0.001, 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=-0.001, SPF_PASS=-0.001, T_HK_NAME_DR=0.01 autolearn=_AUTOLEARN 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: Juan Quintela , qemu-devel , Hailiang Zhang Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: "Qemu-devel" * Lukas Straub (lukasstraub2@web.de) wrote: > cpu_synchronize_all_pre_loadvm() marks all vcpus as dirty, so the > registers are loaded from CPUState before we continue running > the vm. However if we failover during checkpoint, CPUState is not > initialized and the registers are loaded with garbage. This causes > guest hangs and crashes. > > Fix this by using cpu_synchronize_all_states(), which initializes > CPUState from the current cpu registers additionally to marking > the vcpus as dirty. > > Signed-off-by: Lukas Straub OK, so I think you're saying that if the qemu_loadvm_state_main fails because we failover, we now have duff CPU state, where we should just carry on running on the secondary with the current state, so yes Reviewed-by: Dr. David Alan Gilbert > --- > migration/colo.c | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) > > diff --git a/migration/colo.c b/migration/colo.c > index 09168627bc..6b2ad35aa4 100644 > --- a/migration/colo.c > +++ b/migration/colo.c > @@ -696,7 +696,7 @@ static void colo_incoming_process_checkpoint(MigrationIncomingState *mis, > } > > qemu_mutex_lock_iothread(); > - cpu_synchronize_all_pre_loadvm(); > + cpu_synchronize_all_states(); > ret = qemu_loadvm_state_main(mis->from_src_file, mis); > qemu_mutex_unlock_iothread(); > > -- > 2.20.1 > -- Dr. David Alan Gilbert / dgilbert@redhat.com / Manchester, UK