From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753718AbbIWKop (ORCPT ); Wed, 23 Sep 2015 06:44:45 -0400 Received: from zimbra.alphalink.fr ([217.15.80.77]:54493 "EHLO mail-2-cbv2.admin.alphalink.fr" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1751887AbbIWKon convert rfc822-to-8bit (ORCPT ); Wed, 23 Sep 2015 06:44:43 -0400 X-Greylist: delayed 398 seconds by postgrey-1.27 at vger.kernel.org; Wed, 23 Sep 2015 06:44:43 EDT Date: Wed, 23 Sep 2015 12:38:03 +0200 From: Guillaume Nault To: Sedat Dilek Cc: "David S. Miller" , "netdev@vger.kernel.org" , LKML Subject: Re: [Linux 4.2-rc8+...v4.3-rc2] REGRESSION: ppp: circular locking dependency detected: [pppd] ppp_dev_uninit() | rtnl_lock() Message-ID: <20150923103803.GC2869@alphalink.fr> References: MIME-Version: 1.0 Content-Type: text/plain; charset=iso-8859-1 Content-Disposition: inline In-Reply-To: User-Agent: Mutt/1.5.23 (2014-03-12) Content-Transfer-Encoding: 8BIT Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Wed, Sep 23, 2015 at 08:06:16AM +0200, Sedat Dilek wrote: > Without reverting the below culprit ppp patch... > > commit/?id=8cb775bc0a34dc596837e7da03fd22c747be618b > ("ppp: fix device unregistration upon netns deletion") > > ...I have an unstable Internet connection via Network-Manager/ModemManager. > > First I saw this with Linux v4.2. > Thanks for reporting the issue. Can you test this patch ? --- diff --git a/drivers/net/ppp/ppp_generic.c b/drivers/net/ppp/ppp_generic.c index 0481daf..ed00446 100644 --- a/drivers/net/ppp/ppp_generic.c +++ b/drivers/net/ppp/ppp_generic.c @@ -2755,6 +2755,7 @@ static struct ppp *ppp_create_interface(struct net *net, int unit, */ dev_net_set(dev, net); + rtnl_lock(); mutex_lock(&pn->all_ppp_mutex); if (unit < 0) { @@ -2785,7 +2786,7 @@ static struct ppp *ppp_create_interface(struct net *net, int unit, ppp->file.index = unit; sprintf(dev->name, "ppp%d", unit); - ret = register_netdev(dev); + ret = register_netdevice(dev); if (ret != 0) { unit_put(&pn->units_idr, unit); netdev_err(ppp->dev, "PPP: couldn't register device %s (%d)\n", @@ -2797,6 +2798,7 @@ static struct ppp *ppp_create_interface(struct net *net, int unit, atomic_inc(&ppp_unit_count); mutex_unlock(&pn->all_ppp_mutex); + rtnl_unlock(); *retp = 0; return ppp;