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=-8.0 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,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 463CEC433E0 for ; Mon, 15 Jun 2020 12:04:03 +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 CA9B020714 for ; Mon, 15 Jun 2020 12:04:02 +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="bfkh79ac" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org CA9B020714 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]:39362 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1jknqL-0002wb-Q1 for qemu-devel@archiver.kernel.org; Mon, 15 Jun 2020 08:04:01 -0400 Received: from eggs.gnu.org ([2001:470:142:3::10]:43972) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1jknpe-0002P7-If for qemu-devel@nongnu.org; Mon, 15 Jun 2020 08:03:19 -0400 Received: from us-smtp-1.mimecast.com ([205.139.110.61]:38582 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 1jknpb-00060b-AL for qemu-devel@nongnu.org; Mon, 15 Jun 2020 08:03:17 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1592222594; 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=3YTsVU+wVObqC12+TLvCk7zaxY+QeeJH4tYZ3KB10sY=; b=bfkh79acXWsHCLluBCBcNigiBzjnFKa23bzFwatpwneyzsxJgDwUl2O3JLDNSmgN4X/Dps 5JgOClduTWjXWcaAoYAgZ19211b0hPfS+CsiS7JUIdcQnKy8za5Ew20DqfWUYkOKrzHWAr hQNhjDPUfdoPKb+CWNvNxCHY+P9RoXE= 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-160-gPPZe6rOPeuiTMHAzA2XGw-1; Mon, 15 Jun 2020 08:03:12 -0400 X-MC-Unique: gPPZe6rOPeuiTMHAzA2XGw-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 4F4B68C9061; Mon, 15 Jun 2020 12:03:11 +0000 (UTC) Received: from work-vm (ovpn-114-201.ams2.redhat.com [10.36.114.201]) by smtp.corp.redhat.com (Postfix) with ESMTPS id 4FABA5D9CC; Mon, 15 Jun 2020 12:03:02 +0000 (UTC) Date: Mon, 15 Jun 2020 13:03:00 +0100 From: "Dr. David Alan Gilbert" To: "Denis V. Lunev" Subject: Re: [PATCH 1/4] migration/savevm: respect qemu_fclose() error code in save_snapshot() Message-ID: <20200615120300.GI2883@work-vm> References: <20200611171143.21589-1-den@openvz.org> <20200611171143.21589-2-den@openvz.org> MIME-Version: 1.0 In-Reply-To: <20200611171143.21589-2-den@openvz.org> User-Agent: Mutt/1.14.0 (2020-05-02) X-Scanned-By: MIMEDefang 2.79 on 10.5.11.14 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=205.139.110.61; envelope-from=dgilbert@redhat.com; helo=us-smtp-delivery-1.mimecast.com X-detected-operating-system: by eggs.gnu.org: First seen = 2020/06/15 01:12:36 X-ACL-Warn: Detected OS = Linux 2.2.x-3.x [generic] [fuzzy] X-Spam_score_int: -30 X-Spam_score: -3.1 X-Spam_bar: --- X-Spam_report: (-3.1 / 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_H3=-0.01, RCVD_IN_MSPIKE_WL=-0.01, SPF_HELO_NONE=0.001, SPF_PASS=-0.001 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: Kevin Wolf , Fam Zheng , Vladimir Sementsov-Ogievskiy , qemu-block@nongnu.org, Juan Quintela , qemu-devel@nongnu.org, Max Reitz , Denis Plotnikov , Stefan Hajnoczi Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: "Qemu-devel" * Denis V. Lunev (den@openvz.org) wrote: > qemu_fclose() could return error, f.e. if bdrv_co_flush() will return > the error. > > This validation will become more important once we will start waiting of > asynchronous IO operations, started from bdrv_write_vmstate(), which are > coming soon. > > Signed-off-by: Denis V. Lunev > CC: Kevin Wolf > CC: Max Reitz > CC: Stefan Hajnoczi > CC: Fam Zheng > CC: Juan Quintela > CC: "Dr. David Alan Gilbert" > CC: Vladimir Sementsov-Ogievskiy > CC: Denis Plotnikov We check the return value in very few other places; I think in the migration case we do flushes and assume that if the flushes work we were OK; then most of the closes happen on error paths or after points we think we're done. Reviewed-by: Dr. David Alan Gilbert > --- > migration/savevm.c | 8 ++++++-- > 1 file changed, 6 insertions(+), 2 deletions(-) > > diff --git a/migration/savevm.c b/migration/savevm.c > index c00a6807d9..0ff5bb40ed 100644 > --- a/migration/savevm.c > +++ b/migration/savevm.c > @@ -2628,7 +2628,7 @@ int save_snapshot(const char *name, Error **errp) > { > BlockDriverState *bs, *bs1; > QEMUSnapshotInfo sn1, *sn = &sn1, old_sn1, *old_sn = &old_sn1; > - int ret = -1; > + int ret = -1, ret2; > QEMUFile *f; > int saved_vm_running; > uint64_t vm_state_size; > @@ -2712,10 +2712,14 @@ int save_snapshot(const char *name, Error **errp) > } > ret = qemu_savevm_state(f, errp); > vm_state_size = qemu_ftell(f); > - qemu_fclose(f); > + ret2 = qemu_fclose(f); > if (ret < 0) { > goto the_end; > } > + if (ret2 < 0) { > + ret = ret2; > + goto the_end; > + } > > /* The bdrv_all_create_snapshot() call that follows acquires the AioContext > * for itself. BDRV_POLL_WHILE() does not support nested locking because > -- > 2.17.1 > -- Dr. David Alan Gilbert / dgilbert@redhat.com / Manchester, UK