From mboxrd@z Thu Jan 1 00:00:00 1970 From: Kevin Constantine Subject: Re: Kernel Panics in the network stack Date: Fri, 11 Dec 2009 13:50:35 -0800 Message-ID: <4B22BEAB.1080407@gmail.com> References: <4B22B4F2.8080605@gmail.com> <4B22BC1F.607@gmail.com> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: QUOTED-PRINTABLE Cc: netdev@vger.kernel.org To: Eric Dumazet Return-path: Received: from mail-gx0-f212.google.com ([209.85.217.212]:58703 "EHLO mail-gx0-f212.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1757816AbZLKVua (ORCPT ); Fri, 11 Dec 2009 16:50:30 -0500 Received: by gxk4 with SMTP id 4so1562871gxk.8 for ; Fri, 11 Dec 2009 13:50:36 -0800 (PST) In-Reply-To: <4B22BC1F.607@gmail.com> Sender: netdev-owner@vger.kernel.org List-ID: On 12/11/2009 01:39 PM, Eric Dumazet wrote: > Le 11/12/2009 22:09, Kevin Constantine a =E9crit : >> Hey Everyone- >> >> I've been playing with an ARM based linuxstamp >> http://opencircuits.com/Linuxstamp, and I've been seeing kernel pani= cs >> with both 2.6.28.3, and 2.6.30 within an hour or so of turning the >> linuxstamp on. The stack traces always seem to point at functions >> related to networking. I've pasted a couple of the crash outputs be= low. >> The linuxstamp isn't typically doing anything when the crashes occ= ur, >> in fact it'll crash even if I haven't logged in. >> >> If I ifconfig the interface down, the linuxstamp stays up indefinite= ly. >> Any pointers in one direction or another would be much appreciated= =2E >> >> I'm not sure if this is the right audience to help out or if the arm >> lists might be better. But in any event, any help would be really >> appreciated. >> >> >> linuxstamp login: Unable to handle kernel paging request at virtual >> address 183cb7b0 >> pgd =3D c0004000 >> [183cb7b0] *pgd=3D00000000 >> Internal error: Oops: 0 [#1] PREEMPT >> Modules linked in: >> CPU: 0 Not tainted (2.6.30-00002-g0148992 #13) >> PC is at 0x183cb7b0 >> LR is at __udp4_lib_rcv+0x43c/0x72c > > Could you disassemble your vmlinux file, __udp4_lib_rcv function arou= nd LR > , to see which function was called ? This function then cal= led > a wrong pointer (0x183cb7b0 not a kernel pointer) > > Maybe a kernel stack corruption, or bad ram, ... The vmlinux file I'm using has probably changed a number of times since= =20 then. I'll get a fresh stack trace and disassemble that one. I've has this type of problem with several linuxstamps. I'm only able=20 to trigger this panic when the linuxstamp is plugged into a cisco=20 catalyst gigabit switch. Plugging it in at home into a consumer grade=20 10/100 switch, the linuxstamp stays up indefinitely. Also worth noting, I'm seeing the error counts in ifconfig increase=20 steadily. eth0 Link encap:Ethernet HWaddr ac:de:48:00:00:01 inet addr:172.30.194.255 Bcast:172.30.207.255=20 Mask:255.255.240.0 UP BROADCAST RUNNING MULTICAST MTU:1500 Metric:1 RX packets:42492 errors:1442 dropped:0 overruns:6 frame:784 TX packets:1169 errors:0 dropped:0 overruns:0 carrier:0 collisions:0 txqueuelen:1000 RX bytes:3804651 (3.6 MiB) TX bytes:106728 (104.2 KiB) Interrupt:24 Base address:0xc000 -kevin