From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932187AbaENNmc (ORCPT ); Wed, 14 May 2014 09:42:32 -0400 Received: from new2-smtp.messagingengine.com ([66.111.4.224]:59243 "EHLO new2-smtp.messagingengine.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751380AbaENNmb (ORCPT ); Wed, 14 May 2014 09:42:31 -0400 X-Greylist: delayed 427 seconds by postgrey-1.27 at vger.kernel.org; Wed, 14 May 2014 09:42:31 EDT Message-Id: <1400074523.15916.117311749.3590532D@webmail.messagingengine.com> X-Sasl-Enc: vJgMovh8q/E+0Be5IXsNKNGcLGcZpLWCBh1NzoaXBvmX 1400074523 From: Hannes Frederic Sowa To: dormando , linux-kernel@vger.kernel.org, netdev@vger.kernel.org MIME-Version: 1.0 Content-Transfer-Encoding: 7bit Content-Type: text/plain X-Mailer: MessagingEngine.com Webmail Interface - ajax-0867fb17 In-Reply-To: References: Subject: Re: Multitude of dst obsolescense race conditions Date: Wed, 14 May 2014 06:35:23 -0700 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Wed, May 14, 2014, at 2:57, dormando wrote: > Given a machine with frequently changing routes (ie; a router with an > active internet BGP table and multiple interfaces), there're at least > several places where obsolete dst's are handled improperly. If I pause > the > route changes, the crashes appear to stop. This first one has a crash > utility we've made, so I was able to more quickly find a patch and test > it. The others take time to reproduce. > > I'm testing against 3.10.39, but I think if these were fixed they'd be > backported to stable? I've also had recent 3.12's running that have > crashed in the same spots. Anyway correct me if I'm wrong... Just a hunch: You use macvlan? Could you somehow try without? Maybe... some ref overflow? (You could add some testing code in dst_hold with atomic_inc_return and WARN_ON). dst_release already contains such a check, so I am not sure at all if that could happen. Bye, Hannes