From owner-freebsd-current@FreeBSD.ORG Sat Nov 17 22:35:57 2007 Return-Path: Delivered-To: freebsd-current@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:4f8:fff6::34]) by hub.freebsd.org (Postfix) with ESMTP id 1676016A419 for ; Sat, 17 Nov 2007 22:35:57 +0000 (UTC) (envelope-from kip.macy@gmail.com) Received: from wa-out-1112.google.com (wa-out-1112.google.com [209.85.146.181]) by mx1.freebsd.org (Postfix) with ESMTP id E192F13C458 for ; Sat, 17 Nov 2007 22:35:56 +0000 (UTC) (envelope-from kip.macy@gmail.com) Received: by wa-out-1112.google.com with SMTP id k17so1543980waf for ; Sat, 17 Nov 2007 14:35:42 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=beta; h=domainkey-signature:received:received:message-id:date:from:to:subject:cc:in-reply-to:mime-version:content-type:content-transfer-encoding:content-disposition:references; bh=erXAiSpiUHnKEi/aAJ6EDWt8d6XeGc7jaRSwDcHmmps=; b=WFnFFO3tHwUPpNN/lf9Ua+eFfxo+557Y/EdK3cAWaKKb0jHRXbbnDmlkKmXcja3Ont8kethBASn1yt6toH+hKk5RuxJ5WXMlEPYxhPLWeDFq5zabfrg//IivR2cJQGd3n6embrMYSLttDgx+3eTFseB8gy+1Z2expvPqhVWFKtY= DomainKey-Signature: a=rsa-sha1; c=nofws; d=gmail.com; s=beta; h=received:message-id:date:from:to:subject:cc:in-reply-to:mime-version:content-type:content-transfer-encoding:content-disposition:references; b=rrNl+bdFtBDjZOf83ozENoBXEgnmkF42UInpql1YHb4x2oEMm0IESqKXKIUz3hMWPBu0MnH6fj8rSm9HA1IOrQCGdkee++37Jwdy1KULgmxTDo5ZYfWTHiLheTZeVo9ezKS4buKLkH6qKj9bumvZP3JMUdKOpirDf7qv65p8XT4= Received: by 10.114.124.1 with SMTP id w1mr1102725wac.1195338942372; Sat, 17 Nov 2007 14:35:42 -0800 (PST) Received: by 10.114.13.15 with HTTP; Sat, 17 Nov 2007 14:35:42 -0800 (PST) Message-ID: Date: Sat, 17 Nov 2007 14:35:42 -0800 From: "Kip Macy" To: "Mike Andrews" In-Reply-To: <20071117170537.F59492@mindcrime.int.bit0.com> MIME-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Content-Disposition: inline References: <20071117003504.R31357@mindcrime.int.bit0.com> <20071117213316.499be43b@vlink.ru> <20071117170537.F59492@mindcrime.int.bit0.com> Cc: Denis Shaposhnikov , Mike Silbersack , Andre Oppermann , freebsd-current@freebsd.org Subject: Re: bizarre em + TSO + MSS issue in RELENG_7 X-BeenThere: freebsd-current@freebsd.org X-Mailman-Version: 2.1.5 Precedence: list List-Id: Discussions about the use of FreeBSD-current List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Sat, 17 Nov 2007 22:35:57 -0000 On Nov 17, 2007 2:33 PM, Mike Andrews wrote: > On Sat, 17 Nov 2007, Kip Macy wrote: > > > On Nov 17, 2007 10:33 AM, Denis Shaposhnikov wrote: > >> On Sat, 17 Nov 2007 00:42:54 -0500 (EST) > >> Mike Andrews wrote: > >> > >>> Has anyone run into problems with MSS not being respected when using > >>> TSO, specifically on em cards? > >> > >> Yes, I wrote about this problem on the beginning of 2007, see > >> > >> http://tinyurl.com/3e5ak5 > >> > > > > if_em.c:3502 > > /* > > * Payload size per packet w/o any headers. > > * Length of all headers up to payload. > > */ > > TXD->tcp_seg_setup.fields.mss = htole16(mp->m_pkthdr.tso_segsz); > > TXD->tcp_seg_setup.fields.hdr_len = hdr_len; > > > > > > Please print out the value of tso_segsz here. It appears to be being > > set correctly. The only thing I can think of is that t_maxopd is not > > correct. As tso_segsz is correct here: > > > It repeatedly prints 1368 during a 1 meg file transfer over a connection > with a 1380 MSS. Any other printf's I can add? I'm working on a web page > with tcpdump / firewall log output illustrating the issue... Thanks for the quick follow-up. That means that maxopd is not getting initialized correctly, which means I'm going to have add some logging to tcp_input. Which means it will have to wait until this evening at the earliest. This does, however, mean that em is off the hook. It is just doing what it is told. -Kip