From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753695AbZIBWbJ (ORCPT ); Wed, 2 Sep 2009 18:31:09 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1753500AbZIBWbI (ORCPT ); Wed, 2 Sep 2009 18:31:08 -0400 Received: from mail-fx0-f217.google.com ([209.85.220.217]:62584 "EHLO mail-fx0-f217.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751266AbZIBWbG convert rfc822-to-8bit (ORCPT ); Wed, 2 Sep 2009 18:31:06 -0400 DomainKey-Signature: a=rsa-sha1; c=nofws; d=gmail.com; s=gamma; h=mime-version:in-reply-to:references:date:message-id:subject:from:to :cc:content-type:content-transfer-encoding; b=j8A7KNCZkL6xiqNBi63SAVGvAu4e6OFPvU0eTfpfwku8mEkrCnOifx60IIRu4LhPmc 9Vic1Lr8gJQMqbcTQ2tP+Nf28g+/dUyUPbTHHvtTR1Jz1C76xJLUZNE4RYv6Gm5L9Ytt BfGcXnqrU8WtmRLggubt9mvSnzCTLI3eJVxAM= MIME-Version: 1.0 In-Reply-To: <4A9EEF07.5070800@gmail.com> References: <4A87CE60.4020506@gmail.com> <4A896324.3040104@trash.net> <4A9EEF07.5070800@gmail.com> Date: Thu, 3 Sep 2009 00:31:07 +0200 Message-ID: Subject: Re: System freeze on reboot - general protection fault From: Zdenek Kabelac To: Eric Dumazet Cc: Patrick McHardy , Christoph Lameter , Robin Holt , Linux Kernel Mailing List , Pekka Enberg , Jesper Dangaard Brouer , Linux Netdev List , Netfilter Developers Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 8BIT Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 2009/9/3 Eric Dumazet : > Zdenek Kabelac a écrit : >> 2009/8/17 Patrick McHardy : >>> Eric Dumazet wrote: >>>> Zdenek Kabelac a écrit : >>>>>  [] nf_conntrack_ftp_fini+0x2f/0x70 [nf_conntrack_ftp] >>>>>  [] sys_delete_module+0x1a5/0x270 >>>>>  [] ? retint_swapgs+0xe/0x13 >>>>>  [] ? trace_hardirqs_on_caller+0x162/0x1b0 >>>>>  [] ? audit_syscall_entry+0x191/0x1c0 >>>>>  [] ? trace_hardirqs_on_thunk+0x3a/0x3f >>>>>  [] system_call_fastpath+0x16/0x1b >>>>> Code: c6 00 00 0f 82 66 ff ff ff 49 8b 9e d8 05 00 00 48 85 db 75 16 >>>>> e9 8e 00 00 00 0f 1f 44 00 00 48 85 c0 0f 84 80 00 00 00 48 89 c3 <0f> >>>>> b6 4b 37 48 8b 03 48 8d 14 cd 00 00 00 00 0f 18 08 48 29 ca >>>>> RIP  [] nf_conntrack_helper_unregister+0x16c/0x320 >>>>> [nf_conntrack] >>>>>  RSP >>>>> CR2: 0000000000000038 >>>>> ---[ end trace bc3a0ede3d0084db ]--- >>>>> >>>> I am currently traveling and wont be able to help you before next week. >>>> >>>> I added netdev, Patrick, and netfilter-devel in CC so that more eyes can take a look. >>> Thanks for the report, I'll have a look at this. Zdenek, please >>> send me the nf_conntrack.ko file used in the above oops. Thanks. >>> >> >> Ok >> >> I've found the solution for my problem. >> >> http://thread.gmane.org/gmane.comp.security.firewalls.netfilter.devel/30483 >> >> I've made this small fix from this thread: >> >> diff --git a/net/netfilter/nf_conntrack_core.c b/net/netfilter/nf_conntrack_core >> index b5869b9..68488f8 100644 >> --- a/net/netfilter/nf_conntrack_core.c >> +++ b/net/netfilter/nf_conntrack_core.c >> @@ -1108,6 +1108,7 @@ static void nf_conntrack_cleanup_init_net(void) >>  { >>         nf_conntrack_helper_fini(); >>         nf_conntrack_proto_fini(); >> +       rcu_barrier(); >>         kmem_cache_destroy(nf_conntrack_cachep); >>  } >> >> @@ -1266,7 +1267,7 @@ static int nf_conntrack_init_init_net(void) >> >>         nf_conntrack_cachep = kmem_cache_create("nf_conntrack", >>                                                 sizeof(struct nf_conn), >> -                                               0, SLAB_DESTROY_BY_RCU, NULL); >> +                                               0, 0, NULL); >>         if (!nf_conntrack_cachep) { >>                 printk(KERN_ERR "Unable to create nf_conn slab cache\n"); >>                 ret = -ENOMEM; >> >> >> As the thread nf_conntrack: Use rcu_barrier() and fix kmem_cache_create flags >> seems to be samewhat 'unfinished'  and already a bit old and I've no >> idea whether it actually fixes problem completely or just hides it in >> my case - I'm leaving it to some RCU gurus to fix this issue. >> >> All I could say is - this this extra rcu_barrier() and removal of >> SLAB_DESTROY removes my GPF on reboot. >> >> Zdenek > > Ouch.. > > Dont think such a patch makes your kernel better, it'll crash too. > > You cannot remove SLAB_DESTROY_BY_RCU like this, it's there for very good reasons. > Well I'm not noticing any ill behavior - also note - rcu_barrier() is there before the cache is destroyed. But as I said - it's just my shot into the dark - which seems to work for me... Zdenek