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=-5.0 required=3.0 tests=BAYES_00,DKIM_INVALID, DKIM_SIGNED,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE, SPF_PASS,URIBL_BLOCKED,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 9A247C433E0 for ; Tue, 16 Feb 2021 19:33:33 +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 F237864ED6 for ; Tue, 16 Feb 2021 19:33:32 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org F237864ED6 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]:49030 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1lC66F-0003di-Tl for qemu-devel@archiver.kernel.org; Tue, 16 Feb 2021 14:33:31 -0500 Received: from eggs.gnu.org ([2001:470:142:3::10]:52098) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1lC654-0002Um-4L for qemu-devel@nongnu.org; Tue, 16 Feb 2021 14:32:18 -0500 Received: from us-smtp-delivery-124.mimecast.com ([63.128.21.124]:44466) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_CBC_SHA1:256) (Exim 4.90_1) (envelope-from ) id 1lC651-0007R3-W4 for qemu-devel@nongnu.org; Tue, 16 Feb 2021 14:32:17 -0500 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1613503934; 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=oNQzMYNAqpweZSJ2l6hB5W+ppg4Uxm63rFMR3JJFyAA=; b=b6wRKGglr2JZpZY89Q/VGt6sKc8EiEaWeKlpkb/GOC6Gv2kEfe+9EC9huPGweHv62/+JTa BR/2RWtv+fSA42/sc3azYOLhf87xRCZ3ls1JGp4ROW1tNSDhf40MRj4MKrlRkSNURlT+4u J48EPUklNFit/ETCjMvahT/+51IWF20= 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-496-yGW7nGr1NJWmrXRBheGRYg-1; Tue, 16 Feb 2021 14:32:09 -0500 X-MC-Unique: yGW7nGr1NJWmrXRBheGRYg-1 Received: from smtp.corp.redhat.com (int-mx04.intmail.prod.int.phx2.redhat.com [10.5.11.14]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id A495B427C1; Tue, 16 Feb 2021 19:32:08 +0000 (UTC) Received: from work-vm (ovpn-115-109.ams2.redhat.com [10.36.115.109]) by smtp.corp.redhat.com (Postfix) with ESMTPS id 55A945D9D3; Tue, 16 Feb 2021 19:32:07 +0000 (UTC) Date: Tue, 16 Feb 2021 19:32:04 +0000 From: "Dr. David Alan Gilbert" To: Daniel =?iso-8859-1?Q?P=2E_Berrang=E9?= Subject: Re: [PATCH 00/33] migration: capture error reports into Error object Message-ID: References: <20210204171907.901471-1-berrange@redhat.com> <20210204182249.GO3039@work-vm> <20210204190927.GB903389@redhat.com> <20210208132903.GH3032@work-vm> <20210208134206.GH1141037@redhat.com> <20210215185822.GM1542881@redhat.com> MIME-Version: 1.0 In-Reply-To: User-Agent: Mutt/2.0.5 (2021-01-21) X-Scanned-By: MIMEDefang 2.79 on 10.5.11.14 Authentication-Results: relay.mimecast.com; auth=pass smtp.auth=CUSA124A263 smtp.mailfrom=dgilbert@redhat.com X-Mimecast-Spam-Score: 0 X-Mimecast-Originator: redhat.com Content-Type: text/plain; charset=iso-8859-1 Content-Disposition: inline Content-Transfer-Encoding: 8bit Received-SPF: pass client-ip=63.128.21.124; envelope-from=dgilbert@redhat.com; helo=us-smtp-delivery-124.mimecast.com X-Spam_score_int: -27 X-Spam_score: -2.8 X-Spam_bar: -- X-Spam_report: (-2.8 / 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_LOW=-0.7, RCVD_IN_MSPIKE_H4=0.001, RCVD_IN_MSPIKE_WL=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: Juan Quintela , Hailiang Zhang , qemu-devel@nongnu.org Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: "Qemu-devel" * Daniel P. Berrangé (berrange@redhat.com) wrote: > On Mon, Feb 15, 2021 at 07:01:28PM +0000, Dr. David Alan Gilbert wrote: > > * Daniel P. Berrangé (berrange@redhat.com) wrote: > > > On Mon, Feb 15, 2021 at 06:38:05PM +0000, Dr. David Alan Gilbert wrote: > > > > One thing to check, and I *think* you're OK, but we have one place where > > > > we actually check the error number: > > > > > > > > migration.c: > > > > 3414 static MigThrError migration_detect_error(MigrationState *s) > > > > ... > > > > 3426 /* Try to detect any file errors */ > > > > 3427 ret = qemu_file_get_error_obj(s->to_dst_file, &local_error); > > > > 3428 if (!ret) { > > > > 3429 /* Everything is fine */ > > > > 3430 assert(!local_error); > > > > 3431 return MIG_THR_ERR_NONE; > > > > 3432 } > > > > 3433 > > > > 3434 if (local_error) { > > > > 3435 migrate_set_error(s, local_error); > > > > 3436 error_free(local_error); > > > > 3437 } > > > > 3438 > > > > 3439 if (state == MIGRATION_STATUS_POSTCOPY_ACTIVE && ret == -EIO) { > > > > 3440 /* > > > > 3441 * For postcopy, we allow the network to be down for a > > > > 3442 * while. After that, it can be continued by a > > > > 3443 * recovery phase. > > > > 3444 */ > > > > 3445 return postcopy_pause(s); > > > > 3446 } else { > > > > > > > > This is to go into postcopy pause if the network connection broke (but > > > > not if for example a device moaned about being in an invalid state) > > > > > > > > If I read this correctly, file errors are still being preserved - is > > > > that correct? > > > > > > Yes, in places where QemuFile is reporting an actual I/O error I've > > > tried to preserve that. Only removed setting of fake I/O errors. So > > > if anything, we ought to get more accurate at detecting the recoverable > > > scenarios once we fully cleanup errors. > > > > OK, good. > > One scenario to possibly check though is that in a few places we used > error_report_err() but didn't immediately return an error code back to > the caller, instead carrying on doing other calls. It is possible that > we thus reported an error about bad data, and then later hit the EIO > check for QemuFile. That's generally OK; it gets pretty painful to do the qemu file checks after every read. Dave > > Regards, > Daniel > -- > |: https://berrange.com -o- https://www.flickr.com/photos/dberrange :| > |: https://libvirt.org -o- https://fstop138.berrange.com :| > |: https://entangle-photo.org -o- https://www.instagram.com/dberrange :| -- Dr. David Alan Gilbert / dgilbert@redhat.com / Manchester, UK