Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S263801AbUDRSvM (ORCPT ); Sun, 18 Apr 2004 14:51:12 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S263879AbUDRSvM (ORCPT ); Sun, 18 Apr 2004 14:51:12 -0400 Received: from tag.witbe.net ([81.88.96.48]:38410 "EHLO tag.witbe.net") by vger.kernel.org with ESMTP id S263801AbUDRSvG convert rfc822-to-8bit (ORCPT ); Sun, 18 Apr 2004 14:51:06 -0400 Message-Id: <200404181851.i3IIp1107295@tag.witbe.net> Reply-To: From: "Paul Rolland" To: "'Stephen Hemminger'" , "'David S. Miller'" Cc: "'Paul Rolland'" , , Subject: RE: [2.6.5] Bad scheduling while atomic Date: Sun, 18 Apr 2004 20:50:55 +0200 Organization: AS2917 MIME-Version: 1.0 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: 8BIT X-Mailer: Microsoft Office Outlook, Build 11.0.5510 Thread-Index: AcQj8N4vTSnSCAKNT3W50Gg+qBW/wgAAdfUg In-Reply-To: <20040416131633.1bfbfa4c@dell_ss3.pdx.osdl.net> X-MimeOLE: Produced By Microsoft MimeOLE V6.00.2800.1165 Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2231 Lines: 77 Thanks Stephen for being so fast ! Regards, Paul Paul Rolland, rol(at)as2917.net ex-AS2917 Network administrator and Peering Coordinator -- Please no HTML, I'm not a browser - Pas d'HTML, je ne suis pas un navigateur "Some people dream of success... while others wake up and work hard at it" > -----Message d'origine----- > De : linux-kernel-owner@vger.kernel.org > [mailto:linux-kernel-owner@vger.kernel.org] De la part de > Stephen Hemminger > Envoy? : vendredi 16 avril 2004 22:17 > ? : David S. Miller > Cc : Paul Rolland; linux-kernel@vger.kernel.org; netdev@oss.sgi.com > Objet : Re: [2.6.5] Bad scheduling while atomic > > Bring up/down network devices with lapbether causes scheduling while > atomic (if preempt enabled). > > The calls to rcu_read_lock are unnecessary since lapb_device_event > is called from notifier with the rtnetlink semaphore held, it is > already protected from the labp_devices list changing. > > Patch against 2.6.6-rc1 > > diff -Nru a/drivers/net/wan/lapbether.c b/drivers/net/wan/lapbether.c > --- a/drivers/net/wan/lapbether.c Fri Apr 16 11:00:35 2004 > +++ b/drivers/net/wan/lapbether.c Fri Apr 16 11:00:35 2004 > @@ -392,6 +392,8 @@ > > /* > * Handle device status changes. > + * > + * Called from notifier with RTNL held. > */ > static int lapbeth_device_event(struct notifier_block *this, > unsigned long event, void *ptr) > @@ -402,7 +404,6 @@ > if (!dev_is_ethdev(dev)) > return NOTIFY_DONE; > > - rcu_read_lock(); > switch (event) { > case NETDEV_UP: > /* New ethernet device -> new LAPB interface */ > @@ -422,7 +423,6 @@ > lapbeth_free_device(lapbeth); > break; > } > - rcu_read_unlock(); > > return NOTIFY_DONE; > } > - > To unsubscribe from this list: send the line "unsubscribe > linux-kernel" in > the body of a message to majordomo@vger.kernel.org > More majordomo info at http://vger.kernel.org/majordomo-info.html > Please read the FAQ at http://www.tux.org/lkml/ > > - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/