From patchwork Wed Sep 11 16:15:22 2019 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Sergio Lopez X-Patchwork-Id: 1161115 Return-Path: X-Original-To: incoming@patchwork.ozlabs.org Delivered-To: patchwork-incoming@bilbo.ozlabs.org Authentication-Results: ozlabs.org; spf=pass (mailfrom) smtp.mailfrom=nongnu.org (client-ip=209.51.188.17; helo=lists.gnu.org; envelope-from=qemu-devel-bounces+incoming=patchwork.ozlabs.org@nongnu.org; receiver=) Authentication-Results: ozlabs.org; dmarc=fail (p=none dis=none) header.from=redhat.com 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 ozlabs.org (Postfix) with ESMTPS id 46T6X64sVKz9sNx for ; Thu, 12 Sep 2019 02:18:29 +1000 (AEST) Received: from localhost ([::1]:53464 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1i85K5-0005pv-QT for incoming@patchwork.ozlabs.org; Wed, 11 Sep 2019 12:18:26 -0400 Received: from eggs.gnu.org ([2001:470:142:3::10]:37137) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1i85Im-0005oL-24 for qemu-devel@nongnu.org; Wed, 11 Sep 2019 12:17:06 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1i85Ik-0006TZ-6D for qemu-devel@nongnu.org; Wed, 11 Sep 2019 12:17:03 -0400 Received: from mx1.redhat.com ([209.132.183.28]:46840) by eggs.gnu.org with esmtps (TLS1.0:DHE_RSA_AES_256_CBC_SHA1:32) (Exim 4.71) (envelope-from ) id 1i85Ih-0006Q7-Iq; Wed, 11 Sep 2019 12:16:59 -0400 Received: from smtp.corp.redhat.com (int-mx05.intmail.prod.int.phx2.redhat.com [10.5.11.15]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mx1.redhat.com (Postfix) with ESMTPS id BFB0918CB8E7; Wed, 11 Sep 2019 16:16:58 +0000 (UTC) Received: from dritchie.redhat.com (unknown [10.33.36.160]) by smtp.corp.redhat.com (Postfix) with ESMTP id BA2035D704; Wed, 11 Sep 2019 16:16:52 +0000 (UTC) From: Sergio Lopez To: qemu-block@nongnu.org Date: Wed, 11 Sep 2019 18:15:22 +0200 Message-Id: <20190911161521.59261-1-slp@redhat.com> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 2.79 on 10.5.11.15 X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.6.2 (mx1.redhat.com [10.5.110.63]); Wed, 11 Sep 2019 16:16:58 +0000 (UTC) X-detected-operating-system: by eggs.gnu.org: GNU/Linux 2.2.x-3.x [generic] X-Received-From: 209.132.183.28 Subject: [Qemu-devel] [PATCH] nbd/server: attach client channel to the export's AioContext 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, qemu-devel@nongnu.org, Sergio Lopez Errors-To: qemu-devel-bounces+incoming=patchwork.ozlabs.org@nongnu.org Sender: "Qemu-devel" On creation, the export's AioContext is set to the same one as the BlockBackend, while the AioContext in the client QIOChannel is left untouched. As a result, when using data-plane, nbd_client_receive_next_request() schedules coroutines in the IOThread AioContext, while the client's QIOChannel is serviced from the main_loop, potentially triggering the assertion at qio_channel_restart_[read|write]. To fix this, as soon we have the export corresponding to the client, we call qio_channel_attach_aio_context() to attach the QIOChannel context to the export's AioContext. This matches with the logic in blk_aio_attached(). RHBZ: https://bugzilla.redhat.com/show_bug.cgi?id=1748253 Signed-off-by: Sergio Lopez Reviewed-by: Eric Blake --- nbd/server.c | 2 ++ 1 file changed, 2 insertions(+) diff --git a/nbd/server.c b/nbd/server.c index 10faedcfc5..51322e2343 100644 --- a/nbd/server.c +++ b/nbd/server.c @@ -471,6 +471,7 @@ static int nbd_negotiate_handle_export_name(NBDClient *client, QTAILQ_INSERT_TAIL(&client->exp->clients, client, next); nbd_export_get(client->exp); nbd_check_meta_export(client); + qio_channel_attach_aio_context(client->ioc, client->exp->ctx); return 0; } @@ -673,6 +674,7 @@ static int nbd_negotiate_handle_info(NBDClient *client, uint16_t myflags, QTAILQ_INSERT_TAIL(&client->exp->clients, client, next); nbd_export_get(client->exp); nbd_check_meta_export(client); + qio_channel_attach_aio_context(client->ioc, exp->ctx); rc = 1; } return rc;