From owner-freebsd-bugs@FreeBSD.ORG Fri Nov 6 01:20:02 2009 Return-Path: Delivered-To: freebsd-bugs@hub.freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:4f8:fff6::34]) by hub.freebsd.org (Postfix) with ESMTP id 69E241065670 for ; Fri, 6 Nov 2009 01:20:02 +0000 (UTC) (envelope-from gnats@FreeBSD.org) Received: from freefall.freebsd.org (freefall.freebsd.org [IPv6:2001:4f8:fff6::28]) by mx1.freebsd.org (Postfix) with ESMTP id 2C8B48FC1E for ; Fri, 6 Nov 2009 01:20:02 +0000 (UTC) Received: from freefall.freebsd.org (localhost [127.0.0.1]) by freefall.freebsd.org (8.14.3/8.14.3) with ESMTP id nA61K2wD021712 for ; Fri, 6 Nov 2009 01:20:02 GMT (envelope-from gnats@freefall.freebsd.org) Received: (from gnats@localhost) by freefall.freebsd.org (8.14.3/8.14.3/Submit) id nA61K2A7021711; Fri, 6 Nov 2009 01:20:02 GMT (envelope-from gnats) Resent-Date: Fri, 6 Nov 2009 01:20:02 GMT Resent-Message-Id: <200911060120.nA61K2A7021711@freefall.freebsd.org> Resent-From: FreeBSD-gnats-submit@FreeBSD.org (GNATS Filer) Resent-To: freebsd-bugs@FreeBSD.org Resent-Reply-To: FreeBSD-gnats-submit@FreeBSD.org, Maksym Sobolyev Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:4f8:fff6::34]) by hub.freebsd.org (Postfix) with ESMTP id 247F1106568B for ; Fri, 6 Nov 2009 01:18:12 +0000 (UTC) (envelope-from nobody@FreeBSD.org) Received: from www.freebsd.org (www.freebsd.org [IPv6:2001:4f8:fff6::21]) by mx1.freebsd.org (Postfix) with ESMTP id 1408C8FC1A for ; Fri, 6 Nov 2009 01:18:12 +0000 (UTC) Received: from www.freebsd.org (localhost [127.0.0.1]) by www.freebsd.org (8.14.3/8.14.3) with ESMTP id nA61IBVo027140 for ; Fri, 6 Nov 2009 01:18:11 GMT (envelope-from nobody@www.freebsd.org) Received: (from nobody@localhost) by www.freebsd.org (8.14.3/8.14.3/Submit) id nA61IBJn027139; Fri, 6 Nov 2009 01:18:11 GMT (envelope-from nobody) Message-Id: <200911060118.nA61IBJn027139@www.freebsd.org> Date: Fri, 6 Nov 2009 01:18:11 GMT From: Maksym Sobolyev To: freebsd-gnats-submit@FreeBSD.org X-Send-Pr-Version: www-3.1 Cc: Subject: kern/140326: em0: watchdog timeout when communicating to windows using 9K MTU X-BeenThere: freebsd-bugs@freebsd.org X-Mailman-Version: 2.1.5 Precedence: list List-Id: Bug reports List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Fri, 06 Nov 2009 01:20:02 -0000 >Number: 140326 >Category: kern >Synopsis: em0: watchdog timeout when communicating to windows using 9K MTU >Confidential: no >Severity: serious >Priority: high >Responsible: freebsd-bugs >State: open >Quarter: >Keywords: >Date-Required: >Class: sw-bug >Submitter-Id: current-users >Arrival-Date: Fri Nov 06 01:20:01 UTC 2009 >Closed-Date: >Last-Modified: >Originator: Maksym Sobolyev >Release: 7.2-p4 >Organization: Sippy Software, Inc. >Environment: FreeBSD pioneer.sippysoft.com 7.2-RELEASE-p4 FreeBSD 7.2-RELEASE-p4 #0: Sun Oct 4 03:08:04 PDT 2009 root@pioneer.sippysoft.com:/usr/obj/usr/src/sys/PIONEER amd64 >Description: My em0 interface repeatedly hangs up with watchdog timeout when communicating to the windows host at MTU 9K. [sobomax@pioneer ~]$ grep em0 /var/run/dmesg.boot em0: port 0xecc0-0xecdf mem 0xfe6e0000-0xfe6fffff,0xfe6d9000-0xfe6d9fff irq 21 at device 25.0 on pci0 em0: Using MSI interrupt em0: [FILTER] em0: Ethernet address: 00:22:19:32:87:2f [sobomax@pioneer ~]$ uname -a FreeBSD pioneer.sippysoft.com 7.2-RELEASE-p4 FreeBSD 7.2-RELEASE-p4 #0: Sun Oct 4 03:08:04 PDT 2009 root@pioneer.sippysoft.com:/usr/obj/usr/src/sys/PIONEER amd64 [sobomax@pioneer ~]$ ifconfig em0 em0: flags=8843 metric 0 mtu 9000 options=98 ether 00:22:19:32:87:2f inet 192.168.1.1 netmask 0xffffff00 broadcast 192.168.1.255 inet 192.168.2.1 netmask 0xffffff00 broadcast 192.168.2.255 inet6 fec0::1 prefixlen 64 media: Ethernet autoselect (1000baseTX ) status: active [sobomax@pioneer ~]$ dmesg | grep watchd em0: watchdog timeout -- resetting em0: watchdog timeout -- resetting em0: watchdog timeout -- resetting em0: watchdog timeout -- resetting em0: watchdog timeout -- resetting I have managed to make a packet capture right at the time when hang happens. It appears to be that either "MAC Pause" or "TCP Segment of reassembled PDU" is the last packet that goes through before the interface hangs. Here is the screenshot, if somebody wants to take closer look at the actual packets please let me know. http://sobomax.sippysoft.com/~sobomax/ScreenShot527.png Turning off TSO and TXCSUM/RXCSUM has not helped. Bringing MTU down to 1,500 resolved the issue. I have had the same problem happening several times in the past (although I initially attributed it to the bad cable or something like that), so it's definitely not on-off issue. Given popularity of intel/pro chips in today's computers it look like quite serious issue to me. Any help is greatly appreciated. >How-To-Repeat: >Fix: >Release-Note: >Audit-Trail: >Unformatted: