From patchwork Wed Mar 7 12:59:31 2018 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Ursula Braun X-Patchwork-Id: 882594 X-Patchwork-Delegate: davem@davemloft.net Return-Path: X-Original-To: patchwork-incoming@ozlabs.org Delivered-To: patchwork-incoming@ozlabs.org Authentication-Results: ozlabs.org; spf=none (mailfrom) smtp.mailfrom=vger.kernel.org (client-ip=209.132.180.67; helo=vger.kernel.org; envelope-from=netdev-owner@vger.kernel.org; receiver=) Authentication-Results: ozlabs.org; dmarc=none (p=none dis=none) header.from=linux.vnet.ibm.com Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by ozlabs.org (Postfix) with ESMTP id 3zxDJj1mwzz9sY4 for ; Thu, 8 Mar 2018 00:00:21 +1100 (AEDT) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754522AbeCGNAS (ORCPT ); Wed, 7 Mar 2018 08:00:18 -0500 Received: from mx0a-001b2d01.pphosted.com ([148.163.156.1]:52720 "EHLO mx0a-001b2d01.pphosted.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754397AbeCGNAR (ORCPT ); Wed, 7 Mar 2018 08:00:17 -0500 Received: from pps.filterd (m0098404.ppops.net [127.0.0.1]) by mx0a-001b2d01.pphosted.com (8.16.0.22/8.16.0.22) with SMTP id w27D053m067967 for ; Wed, 7 Mar 2018 08:00:17 -0500 Received: from e06smtp12.uk.ibm.com (e06smtp12.uk.ibm.com [195.75.94.108]) by mx0a-001b2d01.pphosted.com with ESMTP id 2gjec95dh4-1 (version=TLSv1.2 cipher=AES256-SHA256 bits=256 verify=NOT) for ; Wed, 07 Mar 2018 08:00:12 -0500 Received: from localhost by e06smtp12.uk.ibm.com with IBM ESMTP SMTP Gateway: Authorized Use Only! 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Violators will be prosecuted; Wed, 7 Mar 2018 12:59:37 -0000 Received: from d06av25.portsmouth.uk.ibm.com (d06av25.portsmouth.uk.ibm.com [9.149.105.61]) by b06cxnps3074.portsmouth.uk.ibm.com (8.14.9/8.14.9/NCO v10.0) with ESMTP id w27Cxb5k65601630; Wed, 7 Mar 2018 12:59:37 GMT Received: from d06av25.portsmouth.uk.ibm.com (unknown [127.0.0.1]) by IMSVA (Postfix) with ESMTP id 22E1E11C050; Wed, 7 Mar 2018 12:52:23 +0000 (GMT) Received: from d06av25.portsmouth.uk.ibm.com (unknown [127.0.0.1]) by IMSVA (Postfix) with ESMTP id CF77D11C04C; Wed, 7 Mar 2018 12:52:22 +0000 (GMT) Received: from tuxmaker.boeblingen.de.ibm.com (unknown [9.152.85.9]) by d06av25.portsmouth.uk.ibm.com (Postfix) with ESMTPS; Wed, 7 Mar 2018 12:52:22 +0000 (GMT) From: Ursula Braun To: davem@davemloft.net Cc: netdev@vger.kernel.org, linux-s390@vger.kernel.org, schwidefsky@de.ibm.com, heiko.carstens@de.ibm.com, raspl@linux.vnet.ibm.com, ubraun@linux.vnet.ibm.com Subject: [PATCH net 1/1] net/smc: wakeup closing listen socket Date: Wed, 7 Mar 2018 13:59:31 +0100 X-Mailer: git-send-email 2.13.5 In-Reply-To: <20180307125931.42248-1-ubraun@linux.vnet.ibm.com> References: <20180307125931.42248-1-ubraun@linux.vnet.ibm.com> X-TM-AS-GCONF: 00 x-cbid: 18030712-0008-0000-0000-000004D8E828 X-IBM-AV-DETECTION: SAVI=unused REMOTE=unused XFE=unused x-cbparentid: 18030712-0009-0000-0000-00001E6C0354 Message-Id: <20180307125931.42248-2-ubraun@linux.vnet.ibm.com> X-Proofpoint-Virus-Version: vendor=fsecure engine=2.50.10432:, , definitions=2018-03-07_05:, , signatures=0 X-Proofpoint-Spam-Details: rule=outbound_notspam policy=outbound score=0 priorityscore=1501 malwarescore=0 suspectscore=1 phishscore=0 bulkscore=0 spamscore=0 clxscore=1015 lowpriorityscore=0 impostorscore=0 adultscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.0.1-1709140000 definitions=main-1803070151 Sender: netdev-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org Closing of a listen socket wakes up kernel_accept() of smc_tcp_listen_worker(), and then has to wait till smc_tcp_listen_worker() gives up the internal clcsock. This wait is non-interruptible, and does not fit to the interruptible wakeup in smc_tcp_listen_worker(). Thus wakeup fails, and waiting for the closed internal clcsock never ends before the wait timeout is reached. This patch introduces the matching non-interruptible wakeup. Fixes: 127f49705823 ("net/smc: release clcsock from tcp_listen_worker") Reported-by: Hans Wippel Signed-off-by: Ursula Braun --- net/smc/af_smc.c | 16 +++++++++++++++- 1 file changed, 15 insertions(+), 1 deletion(-) diff --git a/net/smc/af_smc.c b/net/smc/af_smc.c index 8cc97834d4f6..ad4c43eb7e7f 100644 --- a/net/smc/af_smc.c +++ b/net/smc/af_smc.c @@ -946,6 +946,20 @@ static void smc_listen_work(struct work_struct *work) goto enqueue; /* queue new sock with sk_err set */ } +/* a non-interruptible variant of sock_def_wakeup() for wakeup of + * smc_close_wait_listen_clcsock() + */ +static void smc_sock_wakeup(struct sock *sk) +{ + struct socket_wq *wq; + + rcu_read_lock(); + wq = rcu_dereference(sk->sk_wq); + if (skwq_has_sleeper(wq)) + wake_up_all(&wq->wait); + rcu_read_unlock(); +} + static void smc_tcp_listen_work(struct work_struct *work) { struct smc_sock *lsmc = container_of(work, struct smc_sock, @@ -981,7 +995,7 @@ static void smc_tcp_listen_work(struct work_struct *work) /* no more listening, wake up smc_close_wait_listen_clcsock and * accept */ - lsk->sk_state_change(lsk); + smc_sock_wakeup(lsk); sock_put(&lsmc->sk); /* sock_hold in smc_listen */ }