From mboxrd@z Thu Jan 1 00:00:00 1970 From: Zdenek Kabelac Subject: Re: System freeze on reboot - general protection fault Date: Wed, 2 Sep 2009 23:45:03 +0200 Message-ID: References: <20090811154853.GF2763@sgi.com> <4A87CE60.4020506@gmail.com> <4A896324.3040104@trash.net> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: QUOTED-PRINTABLE Cc: Eric Dumazet , Christoph Lameter , Robin Holt , Linux Kernel Mailing List , Pekka Enberg , Jesper Dangaard Brouer , Linux Netdev List , Netfilter Developers To: Patrick McHardy Return-path: In-Reply-To: <4A896324.3040104@trash.net> Sender: linux-kernel-owner@vger.kernel.org List-Id: netfilter-devel.vger.kernel.org 2009/8/17 Patrick McHardy : > Eric Dumazet wrote: >> Zdenek Kabelac a =E9crit : >>> =A0[] nf_conntrack_ftp_fini+0x2f/0x70 [nf_conntra= ck_ftp] >>> =A0[] sys_delete_module+0x1a5/0x270 >>> =A0[] ? retint_swapgs+0xe/0x13 >>> =A0[] ? trace_hardirqs_on_caller+0x162/0x1b0 >>> =A0[] ? audit_syscall_entry+0x191/0x1c0 >>> =A0[] ? trace_hardirqs_on_thunk+0x3a/0x3f >>> =A0[] 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 1= 6 >>> 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 =A0[] nf_conntrack_helper_unregister+0x16c/0x= 320 >>> [nf_conntrack] >>> =A0RSP >>> CR2: 0000000000000038 >>> ---[ end trace bc3a0ede3d0084db ]--- >>> >> I am currently traveling and wont be able to help you before next we= ek. >> >> 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/3= 0483 I've made this small fix from this thread: diff --git a/net/netfilter/nf_conntrack_core.c b/net/netfilter/nf_connt= rack_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 =3D 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 =3D -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