Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S261691AbVDPFCT (ORCPT ); Sat, 16 Apr 2005 01:02:19 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S262635AbVDPFCT (ORCPT ); Sat, 16 Apr 2005 01:02:19 -0400 Received: from ms-smtp-04.nyroc.rr.com ([24.24.2.58]:62349 "EHLO ms-smtp-04.nyroc.rr.com") by vger.kernel.org with ESMTP id S261691AbVDPFCP (ORCPT ); Sat, 16 Apr 2005 01:02:15 -0400 Subject: Re: ACPI/HT or Packet Scheduler BUG? From: Steven Rostedt To: Herbert Xu Cc: Thomas Graf , hadi@cyberus.ca, netdev , Tarhon-Onu Victor , kuznet@ms2.inr.ac.ru, devik@cdi.cz, linux-kernel@vger.kernel.org, Patrick McHardy , "David S. Miller" In-Reply-To: <20050416014906.GA3291@gondor.apana.org.au> References: <1113601029.4294.80.camel@localhost.localdomain> <1113601446.17859.36.camel@localhost.localdomain> <1113602052.4294.89.camel@localhost.localdomain> <20050415225422.GF4114@postel.suug.ch> <20050416014906.GA3291@gondor.apana.org.au> Content-Type: text/plain Organization: Kihon Technologies Date: Sat, 16 Apr 2005 01:01:37 -0400 Message-Id: <1113627698.4294.132.camel@localhost.localdomain> Mime-Version: 1.0 X-Mailer: Evolution 2.2.1.1 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1570 Lines: 39 On Sat, 2005-04-16 at 11:49 +1000, Herbert Xu wrote: > Here is a quick'n'dirty fix to the problem at hand. What happened > between 2.6.10-rc1 and 2.6.10-rc2 is that qdisc_destroy started > changing the next pointer of qdisc entries which totally confuses > the readers because qdisc_destroy doesn't always take the tree lock. > > This patch tries to ensure that all top-level calls to qdisc_destroy > come under the tree lock. As Thomas correctedly pointed out, most > of the other qdisc_destroy calls occur after the top qdisc has been > unlinked from the device qdisc_list. However, someone should go > through each one of the remaining ones (they're all in the individual > sch_* implementations) and make sure that this assumption is really > true. > > Signed-off-by: Herbert Xu > > If anyone has cycles to spare and a stomach strong enough for > this stuff, here is your chance :) > FYI, I ran the test case that Tarhon-Ohn had, but had to change his tc execution from batch to single lines since the version of tc I have segfaults on newlines. Anyway, I did see the lock up with 2.6.11.2 after 7 iterations. I applied your patch, and it ran for 30 iterations before I manually killed it. I didn't test any more than that, but this seems to be the quick fix for now. -- Steve - 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/