From patchwork Thu Jun 13 13:09:47 2013 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Benjamin Poirier X-Patchwork-Id: 251071 X-Patchwork-Delegate: davem@davemloft.net Return-Path: X-Original-To: patchwork-incoming@ozlabs.org Delivered-To: patchwork-incoming@ozlabs.org Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by ozlabs.org (Postfix) with ESMTP id 6E4922C0040 for ; Thu, 13 Jun 2013 23:10:13 +1000 (EST) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1757499Ab3FMNKJ (ORCPT ); Thu, 13 Jun 2013 09:10:09 -0400 Received: from mail-qe0-f43.google.com ([209.85.128.43]:34075 "EHLO mail-qe0-f43.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1756720Ab3FMNKE (ORCPT ); Thu, 13 Jun 2013 09:10:04 -0400 Received: by mail-qe0-f43.google.com with SMTP id q19so3096619qeb.16 for ; Thu, 13 Jun 2013 06:10:03 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20120113; h=sender:from:to:cc:subject:date:message-id:x-mailer; bh=c6CPMc9qm5sWxuLRprHmKz7P2ng/tuBC43bXVtelq44=; b=QAaAE1+w8uWVUisjUVoBpFqPEoI7wpf+ZPP//f+Bu9gwlfnGETmLSk2fWbXnEBHvMt 3pWqb1C6Htm95h7TrfYUiUSXBhINp1JkK9cin+N3TH6mTbWRo7/5X/EoeoIzpdMCvddJ BFRDYiW8DLALsDh5pq6FULnKmE7hRazw2gqjt++Cr5yERlqz8l434ha2NGQD9q0df9Ln 7AvTg0hDxyOE4C8DavWPmK0zxT7x2BkghLv5klp1sQjHUfNOGWBW51G7KaGOvV2d55DW WeT2qQAH1KliYyYCCsJCSK4D1oTODnRZyGJkdjC/gMKb7emnHWCtpRBHGehA7sU628cN TPNw== X-Received: by 10.49.1.74 with SMTP id 10mr1209987qek.20.1371129003358; Thu, 13 Jun 2013 06:10:03 -0700 (PDT) Received: from d2.synalogic.ca (modemcable009.218-81-70.mc.videotron.ca. [70.81.218.9]) by mx.google.com with ESMTPSA id pg6sm13557199qeb.5.2013.06.13.06.10.02 for (version=TLSv1.2 cipher=ECDHE-RSA-RC4-SHA bits=128/128); Thu, 13 Jun 2013 06:10:02 -0700 (PDT) From: Benjamin Poirier To: linux-s390@vger.kernel.org Cc: netdev@vger.kernel.org, Ursula Braun , linux390@de.ibm.com, Frank Blaschka , Martin Schwidefsky , Heiko Carstens , Cornelia Huck , linux-kernel@vger.kernel.org Subject: [PATCH] netiucv: Hold rtnl between name allocation and device registration. Date: Thu, 13 Jun 2013 09:09:47 -0400 Message-Id: <1371128987-3723-1-git-send-email-bpoirier@suse.de> X-Mailer: git-send-email 1.7.10.4 Sender: netdev-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org fixes a race condition between concurrent initializations of netiucv devices that try to use the same name. sysfs: cannot create duplicate filename '/devices/iucv/netiucv2' [...] Call Trace: ([<00000000002edea4>] sysfs_add_one+0xb0/0xdc) [<00000000002eecd4>] create_dir+0x80/0xfc [<00000000002eee38>] sysfs_create_dir+0xe8/0x118 [<00000000003835a8>] kobject_add_internal+0x120/0x2d0 [<00000000003839d6>] kobject_add+0x62/0x9c [<00000000003d9564>] device_add+0xcc/0x510 [<000003e00212c7b4>] netiucv_register_device+0xc0/0x1ec [netiucv] Signed-off-by: Benjamin Poirier Tested-by: Ursula Braun --- drivers/s390/net/netiucv.c | 6 +++++- 1 file changed, 5 insertions(+), 1 deletion(-) diff --git a/drivers/s390/net/netiucv.c b/drivers/s390/net/netiucv.c index 4ffa66c..9ca3996 100644 --- a/drivers/s390/net/netiucv.c +++ b/drivers/s390/net/netiucv.c @@ -2040,6 +2040,7 @@ static struct net_device *netiucv_init_netdevice(char *username, char *userdata) netiucv_setup_netdevice); if (!dev) return NULL; + rtnl_lock(); if (dev_alloc_name(dev, dev->name) < 0) goto out_netdev; @@ -2061,6 +2062,7 @@ static struct net_device *netiucv_init_netdevice(char *username, char *userdata) out_fsm: kfree_fsm(privptr->fsm); out_netdev: + rtnl_unlock(); free_netdev(dev); return NULL; } @@ -2100,6 +2102,7 @@ static ssize_t conn_write(struct device_driver *drv, rc = netiucv_register_device(dev); if (rc) { + rtnl_unlock(); IUCV_DBF_TEXT_(setup, 2, "ret %d from netiucv_register_device\n", rc); goto out_free_ndev; @@ -2109,7 +2112,8 @@ static ssize_t conn_write(struct device_driver *drv, priv = netdev_priv(dev); SET_NETDEV_DEV(dev, priv->dev); - rc = register_netdev(dev); + rc = register_netdevice(dev); + rtnl_unlock(); if (rc) goto out_unreg;