From owner-freebsd-stable@FreeBSD.ORG Fri Jul 7 19:00:59 2006 Return-Path: X-Original-To: freebsd-stable@FreeBSD.org Delivered-To: freebsd-stable@FreeBSD.org Received: from mx1.FreeBSD.org (mx1.freebsd.org [216.136.204.125]) by hub.freebsd.org (Postfix) with ESMTP id 8842B16A4DF; Fri, 7 Jul 2006 19:00:59 +0000 (UTC) (envelope-from atanas@asd.aplus.net) Received: from pro20.abac.com (pro20.abac.com [66.226.64.21]) by mx1.FreeBSD.org (Postfix) with ESMTP id 2E47143D5F; Fri, 7 Jul 2006 19:00:48 +0000 (GMT) (envelope-from atanas@asd.aplus.net) Received: from [216.55.129.5] (asd2.aplus.net [216.55.129.5]) (authenticated bits=0) by pro20.abac.com (8.13.6/8.13.6) with ESMTP id k67J0hZR055075 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-SHA bits=256 verify=NO); Fri, 7 Jul 2006 12:00:44 -0700 (PDT) (envelope-from atanas@asd.aplus.net) Message-ID: <44AEB0CB.5060102@asd.aplus.net> Date: Fri, 07 Jul 2006 12:06:51 -0700 From: Atanas User-Agent: Thunderbird 1.5.0.4 (Macintosh/20060516) MIME-Version: 1.0 To: Robert Watson References: <20060629083130.X1229@ganymede.hub.org> <44A4A02A.9060802@thebeastie.org> <20060630012615.Q1103@ganymede.hub.org> <44A57B71.6020201@asd.aplus.net> <20060701035416.GC54876@cdnetworks.co.kr> <44AC6793.2070608@asd.aplus.net> <20060706021444.GA76865@cdnetworks.co.kr> <44AD7297.7080605@asd.aplus.net> <20060707010341.GD82406@cdnetworks.co.kr> <44ADC2ED.4070904@asd.aplus.net> <20060707040838.GE82406@cdnetworks.co.kr> <20060707151640.D51390@fledge.watson.org> In-Reply-To: <20060707151640.D51390@fledge.watson.org> Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit X-Spam-Score: 1.47 (SPF_SOFTFAIL) Cc: Pyun YongHyeon , Peter Jeremy , freebsd-stable@FreeBSD.org, Michael Vince , User Freebsd Subject: Re: em device hangs on ifconfig alias ... X-BeenThere: freebsd-stable@freebsd.org X-Mailman-Version: 2.1.5 Precedence: list List-Id: Production branch of FreeBSD source code List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Fri, 07 Jul 2006 19:00:59 -0000 Robert Watson said the following on 7/7/06 7:17 AM: >> > I just left a "tcpdump -n arp host 10.10.64.40" on a third machine > >> sniffing around and tested all em module versions I had (the stock >> 6.1, > 6-STABLE and 6-STABLE with your patch), but got silence on all >> three: >> >> That's odd. I've tested it on CURRENT and I could see the ARP packet. >> Are you sure you patched correctly? If so I have to build a RELENG_6 >> machine and give it try. > > Is it possible you're seeing an interaction between the reset generated > as part of IP address changing, and the time it takes to negotiate > link? It's possible that the arp packets are being eaten during the > link negotiation, so for systems negotiating quickly (or not at all) > then the arp packet is seen on other hosts, and otherwise not... > Looks like this is exactly what happens. I was able to see it by running two tcpdump instances - one on the EM machine running in background and another running elsewhere on the same subnet. So on the EM machine the arp packet actually gets generated by em(4) and caught by the tcpdump running there: EM# tcpdump -n arp and ether src 00:04:23:b5:1b:ff & EM# EM# ifconfig em1 inet alias 10.10.64.40 EM# 11:28:37.178946 arp who-has 10.10.64.40 tell 10.10.64.40 EM# But it doesn't reach the other tcpdump instance running on another host. It seems that the arp packet gets killed before leaving the EM machine, due to the card initialization or something else. I tried sending it manually with arping, just to make sure both tcpdumps operate properly and yes, the packet got delivered to both. I think that I have patched, built and loaded the em(4) kernel module correctly. After applying the patch there were no rejects, before building the module I intentionally appended " (patched)" to its version string in if_em.c, and could see that in dmesg every time I loaded the module: em1: Regards, Atanas