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=-10.0 required=3.0 tests=BAYES_00,DKIM_INVALID, DKIM_SIGNED,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,NICE_REPLY_A, SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,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 AA70EC433DF for ; Thu, 23 Jul 2020 18:53:27 +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 5AC5420737 for ; Thu, 23 Jul 2020 18:53:27 +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="Y5mVH8xo" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 5AC5420737 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]:47780 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1jygLO-0001f9-Ke for qemu-devel@archiver.kernel.org; Thu, 23 Jul 2020 14:53:26 -0400 Received: from eggs.gnu.org ([2001:470:142:3::10]:58686) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1jygKd-00017X-37 for qemu-devel@nongnu.org; Thu, 23 Jul 2020 14:52:40 -0400 Received: from us-smtp-delivery-1.mimecast.com ([205.139.110.120]:48508 helo=us-smtp-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 1jygKY-0004XZ-0Q for qemu-devel@nongnu.org; Thu, 23 Jul 2020 14:52:38 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1595530352; 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=qm1Kwtn/7hrItqSXjKy00teoNkk4eOEkoa19hw2Sf/c=; b=Y5mVH8xo8G0N3FDJdQkWRzsGDSbV8Y6dck1CXDUc1/4SYmWq6UD99VfJhanWl7Rvlubbh/ 1JFT1zY/DJZoRgNi1+e6Us+EiI/EERderbu6C+93j92ZXkOauU4NHZRUA+6CVpvHskKIpc MFTAfWFOjlJicEeJZOJpJwMWTu85cj4= 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-398-i6wsGoj9M0OFxwhQk62UTQ-1; Thu, 23 Jul 2020 14:52:26 -0400 X-MC-Unique: i6wsGoj9M0OFxwhQk62UTQ-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 3A6E457; Thu, 23 Jul 2020 18:52:25 +0000 (UTC) Received: from [10.3.112.189] (ovpn-112-189.phx2.redhat.com [10.3.112.189]) by smtp.corp.redhat.com (Postfix) with ESMTPS id BEEF35C1BD; Thu, 23 Jul 2020 18:52:24 +0000 (UTC) Subject: Re: [PATCH 2/3] block/nbd: on shutdown terminate connection attempt To: Vladimir Sementsov-Ogievskiy , qemu-block@nongnu.org References: <20200720090024.18186-1-vsementsov@virtuozzo.com> <20200720090024.18186-3-vsementsov@virtuozzo.com> From: Eric Blake Organization: Red Hat, Inc. Message-ID: <98cebab5-c0a4-11fd-2582-dc7210f3a622@redhat.com> Date: Thu, 23 Jul 2020 13:52:19 -0500 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: <20200720090024.18186-3-vsementsov@virtuozzo.com> Content-Language: en-US X-Scanned-By: MIMEDefang 2.79 on 10.5.11.16 X-Mimecast-Spam-Score: 0 X-Mimecast-Originator: redhat.com Content-Type: text/plain; charset=utf-8; format=flowed Content-Transfer-Encoding: 7bit Received-SPF: pass client-ip=205.139.110.120; envelope-from=eblake@redhat.com; helo=us-smtp-1.mimecast.com X-detected-operating-system: by eggs.gnu.org: First seen = 2020/07/23 06:04:25 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=unavailable 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, den@openvz.org, qemu-devel@nongnu.org, mreitz@redhat.com Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: "Qemu-devel" On 7/20/20 4:00 AM, Vladimir Sementsov-Ogievskiy wrote: > On shutdown nbd driver may be in a connecting state. We should shutdown > it as well, otherwise we may hang in > nbd_teardown_connection, waiting for conneciton_co to finish in > BDRV_POLL_WHILE(bs, s->connection_co) loop if remote server is down. > > How to reproduce the dead lock: > Same reproducer as in the previous patch (again, where a temporary sleep or well-placed gdb breakpoint may be more reliable than running two process loops). > > Signed-off-by: Vladimir Sementsov-Ogievskiy > --- > block/nbd.c | 14 ++++++++++---- > 1 file changed, 10 insertions(+), 4 deletions(-) > Reviewed-by: Eric Blake -- Eric Blake, Principal Software Engineer Red Hat, Inc. +1-919-301-3226 Virtualization: qemu.org | libvirt.org