Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754616Ab1FGW5R (ORCPT ); Tue, 7 Jun 2011 18:57:17 -0400 Received: from stinky.trash.net ([213.144.137.162]:63095 "EHLO stinky.trash.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751273Ab1FGW5P (ORCPT ); Tue, 7 Jun 2011 18:57:15 -0400 Message-ID: <4DEEACC3.3030509@trash.net> Date: Wed, 08 Jun 2011 00:57:07 +0200 From: Patrick McHardy User-Agent: Mozilla/5.0 (X11; U; Linux x86_64; en-US; rv:1.9.1.10) Gecko/20100620 Icedove/3.0.5 MIME-Version: 1.0 To: Eric Dumazet CC: Brad Campbell , Bart De Schuymer , kvm@vger.kernel.org, linux-mm@kvack.org, linux-kernel@vger.kernel.org, netdev@vger.kernel.org, netfilter-devel@vger.kernel.org Subject: Re: KVM induced panic on 2.6.38[2367] & 2.6.39 References: <20110601011527.GN19505@random.random> <4DE5DCA8.7070704@fnarfbargle.com> <4DE5E29E.7080009@redhat.com> <4DE60669.9050606@fnarfbargle.com> <4DE60918.3010008@redhat.com> <4DE60940.1070107@redhat.com> <4DE61A2B.7000008@fnarfbargle.com> <20110601111841.GB3956@zip.com.au> <4DE62801.9080804@fnarfbargle.com> <20110601230342.GC3956@zip.com.au> <4DE8E3ED.7080004@fnarfbargle.com> <4DE906C0.6060901@fnarfbargle.com> <4DED344D.7000005@pandora.be> <4DED9C23.2030408@fnarfbargle.com> <4DEE27DE.7060004@trash.net> <4DEE3859.6070808@fnarfbargle.com> <4DEE4538.1020404@trash.net> <1307471484.3091.43.camel@edumazet-laptop> In-Reply-To: <1307471484.3091.43.camel@edumazet-laptop> X-Enigmail-Version: 1.0.1 Content-Type: text/plain; charset=ISO-8859-15 Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1529 Lines: 39 On 07.06.2011 20:31, Eric Dumazet wrote: > Le mardi 07 juin 2011 ? 17:35 +0200, Patrick McHardy a ?crit : > >> The main suspects would be NAT and TCPMSS. Did you also try whether >> the crash occurs with only one of these these rules? >> >>> I've just compiled out CONFIG_BRIDGE_NETFILTER and can no longer access >>> the address the way I was doing it, so that's a no-go for me. >> >> That's really weird since you're apparently not using any bridge >> netfilter features. It shouldn't have any effect besides changing >> at which point ip_tables is invoked. How are your network devices >> configured (specifically any bridges)? > > Something in the kernel does > > u16 *ptr = addr (given by kmalloc()) > > ptr[-1] = 0; > > Could be an off-one error in a memmove()/memcopy() or loop... > > I cant see a network issue here. So far me neither, but netfilter appears to trigger the bug. > I checked arch/x86/lib/memmove_64.S and it seems fine. I was thinking it might be a missing skb_make_writable() combined with vhost_net specifics in the netfilter code (TCPMSS and NAT are both suspect), but was unable to find something. I also went through the dst_metrics() conversion to see whether anything could cause problems with the bridge fake_rttable, but also nothing so far. -- 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/