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=-13.5 required=3.0 tests=BAYES_00,DKIM_INVALID, DKIM_SIGNED,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED 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 1931AC433DB for ; Tue, 2 Feb 2021 23:09:47 +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 B578564E41 for ; Tue, 2 Feb 2021 23:09:46 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org B578564E41 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]:50204 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1l74np-0001bN-Mj for qemu-devel@archiver.kernel.org; Tue, 02 Feb 2021 18:09:45 -0500 Received: from eggs.gnu.org ([2001:470:142:3::10]:40620) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1l74R1-0007md-Pc for qemu-devel@nongnu.org; Tue, 02 Feb 2021 17:46:13 -0500 Received: from us-smtp-delivery-124.mimecast.com ([216.205.24.124]:38180) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_CBC_SHA1:256) (Exim 4.90_1) (envelope-from ) id 1l74Qm-000635-1e for qemu-devel@nongnu.org; Tue, 02 Feb 2021 17:46:11 -0500 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1612305955; 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=xXhQmOU+ikfahQNam6ErItlekmPw+N6cXoaZ0kI8A1A=; b=Zw/9QSCEyB/xAOzU574IyjW6W8VNZZa3psv6KxwqefMe0J81tvGXEY/0ZHUfAj935VLuF6 aTcz/sYSx3RqOec7N5fIlxIwKXC+GEdEbz6t9WcS0P5cAdxwnS6Hf2w+MEwDNCpWuZe3em 3Zpah1vOzYtS++e/u9xfIe9mjS0Z6SU= 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-459-oXeLeISINQ-bwd7g2h1opg-1; Tue, 02 Feb 2021 17:45:52 -0500 X-MC-Unique: oXeLeISINQ-bwd7g2h1opg-1 Received: from smtp.corp.redhat.com (int-mx07.intmail.prod.int.phx2.redhat.com [10.5.11.22]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id A7499801AC1; Tue, 2 Feb 2021 22:45:50 +0000 (UTC) Received: from blue.redhat.com (ovpn-112-103.phx2.redhat.com [10.3.112.103]) by smtp.corp.redhat.com (Postfix) with ESMTP id 27D8010016FD; Tue, 2 Feb 2021 22:45:50 +0000 (UTC) From: Eric Blake To: qemu-devel@nongnu.org Subject: [PULL 20/20] nbd: make nbd_read* return -EIO on error Date: Tue, 2 Feb 2021 16:45:29 -0600 Message-Id: <20210202224529.642055-21-eblake@redhat.com> In-Reply-To: <20210202224529.642055-1-eblake@redhat.com> References: <20210202224529.642055-1-eblake@redhat.com> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 2.84 on 10.5.11.22 Authentication-Results: relay.mimecast.com; auth=pass smtp.auth=CUSA124A263 smtp.mailfrom=eblake@redhat.com X-Mimecast-Spam-Score: 0 X-Mimecast-Originator: redhat.com Content-Transfer-Encoding: 8bit Content-Type: text/plain; charset="US-ASCII" Received-SPF: pass client-ip=216.205.24.124; envelope-from=eblake@redhat.com; helo=us-smtp-delivery-124.mimecast.com X-Spam_score_int: -31 X-Spam_score: -3.2 X-Spam_bar: --- X-Spam_report: (-3.2 / 5.0 requ) BAYES_00=-1.9, DKIMWL_WL_HIGH=-0.386, 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_H3=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: Roman Kagan , Kevin Wolf , Vladimir Sementsov-Ogievskiy , "open list:Network Block Dev..." , Max Reitz Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: "Qemu-devel" From: Roman Kagan NBD reconnect logic considers the error code from the functions that read NBD messages to tell if reconnect should be attempted or not: it is attempted on -EIO, otherwise the client transitions to NBD_CLIENT_QUIT state (see nbd_channel_error). This error code is propagated from the primitives like nbd_read. The problem, however, is that nbd_read itself turns every error into -1 rather than -EIO. As a result, if the NBD server happens to die while sending the message, the client in QEMU receives less data than it expects, considers it as a fatal error, and wouldn't attempt reestablishing the connection. Fix it by turning every negative return from qio_channel_read_all into -EIO returned from nbd_read. Apparently that was the original behavior, but got broken later. Also adjust nbd_readXX to follow. Fixes: e6798f06a6 ("nbd: generalize usage of nbd_read") Signed-off-by: Roman Kagan Reviewed-by: Vladimir Sementsov-Ogievskiy Message-Id: <20210129073859.683063-4-rvkagan@yandex-team.ru> Signed-off-by: Eric Blake --- include/block/nbd.h | 7 ++++--- 1 file changed, 4 insertions(+), 3 deletions(-) diff --git a/include/block/nbd.h b/include/block/nbd.h index 4a52a43ef598..5f34d23bb037 100644 --- a/include/block/nbd.h +++ b/include/block/nbd.h @@ -364,7 +364,7 @@ static inline int nbd_read(QIOChannel *ioc, void *buffer, size_t size, if (desc) { error_prepend(errp, "Failed to read %s: ", desc); } - return -1; + return ret; } return 0; @@ -375,8 +375,9 @@ static inline int nbd_read##bits(QIOChannel *ioc, \ uint##bits##_t *val, \ const char *desc, Error **errp) \ { \ - if (nbd_read(ioc, val, sizeof(*val), desc, errp) < 0) { \ - return -1; \ + int ret = nbd_read(ioc, val, sizeof(*val), desc, errp); \ + if (ret < 0) { \ + return ret; \ } \ *val = be##bits##_to_cpu(*val); \ return 0; \ -- 2.30.0