From owner-freebsd-current@FreeBSD.ORG Tue Jun 22 02:06:47 2010 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 D00CB106564A for ; Tue, 22 Jun 2010 02:06:47 +0000 (UTC) (envelope-from lstewart@freebsd.org) Received: from lauren.room52.net (lauren.room52.net [210.50.193.198]) by mx1.freebsd.org (Postfix) with ESMTP id 578938FC12 for ; Tue, 22 Jun 2010 02:06:47 +0000 (UTC) Received: from lawrence1.loshell.room52.net (unknown [59.167.184.191]) by lauren.room52.net (Postfix) with ESMTPSA id 234B97E84A; Tue, 22 Jun 2010 12:06:45 +1000 (EST) Message-ID: <4C201AB4.6090708@freebsd.org> Date: Tue, 22 Jun 2010 12:06:44 +1000 From: Lawrence Stewart User-Agent: Mozilla/5.0 (X11; U; FreeBSD amd64; en-AU; rv:1.9.1.9) Gecko/20100405 Thunderbird/3.0.4 MIME-Version: 1.0 To: Fabian Keil References: <4C1492D0.6020704@freebsd.org> <4C1C3922.2050102@freebsd.org> <20100619195823.53a7baaa@r500.local> <4C1DED16.8020209@freebsd.org> <20100620131544.495ddecd@r500.local> <4C1E019F.6060802@freebsd.org> <20100620142841.4803dac3@r500.local> <4C1E0E14.3090506@freebsd.org> <20100620151554.58e486db@r500.local> <20100620161242.59381341@r500.local> <20100620213601.050fcf3e@r500.local> <6CE5B32B-2C82-436D-82E3-489D2D22C7EA@lavabit.com> <4C1EE644.3070105@freebsd.org> <20100621205228.0e5332cc@r500.local> In-Reply-To: <20100621205228.0e5332cc@r500.local> Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Cc: freebsd-current@freebsd.org Subject: Re: [CFT] SIFTR - Statistical Information For TCP Research: Uncle Lawrence needs YOU! 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: Tue, 22 Jun 2010 02:06:47 -0000 On 06/22/10 04:52, Fabian Keil wrote: > Lawrence Stewart wrote: > >> On 06/21/10 05:44, Rui Paulo wrote: >>> >>> On 20 Jun 2010, at 20:36, Fabian Keil wrote: >>> >>>> Fabian Keil wrote: >>>> >>>>> Fabian Keil wrote: >>>> >>>>>> My custom kernel normally doesn't have INVARIANTS and WITNESS >>>>>> enabled, so I'll try to enable them next. >>>>> >>>>> The culprit seem to be non-default KTR settings in the kernel >>>>> while loading alq as a module. >>>> >>>> Actually whether or not alq is loaded as a module doesn't >>>> seem to matter, with: >>>> >>>> options KTR >>>> options KTR_ENTRIES=262144 >>>> options KTR_COMPILE=(KTR_SCHED) >>>> options KTR_MASK=(KTR_SCHED) >>>> options KTR_CPUMASK=0x3 >>>> options ALQ >>>> options KTR_ALQ >>>> >>>> enabling siftr panics the system, too. >>> >>> That's probably because your module was built with different compile time options than the ones used in the kernel. These options may change structure sizes, function parameters, etc. and that easily causes panics. >> >> hmm I wonder if my instructions to build SIFTR manually are causing your >> problems. Fabian, is the siftr.ko module you're loading built as part of >> a "make buildkernel", or did you follow my instructions and "cd >> /sys/modules/siftr ; make ; kldload ./siftr.ko"? > > The latter. > >> If the latter is true, perhaps try and explicitly build SIFTR as part of >> "make buildkernel" and see if loading the module built that way still >> triggers the panic when enabled (the module will be in >> /usr/obj//sys//modules//sys/modules/siftr/siftr.ko >> or if you "make installkernel" it'll be in /boot/kernel/kernel/siftr.ko). > > That seems to work. Damn, well this is the first time I've encountered a problem like this whilst using SIFTR compiled standalone and I've been using it like that for almost 3 years. I guess the lack of KTR in the module build subtly influences the module in a way that allows it load but in a precarious way. How irritating. Rui you were right on the money! I will revise my testing instructions to build the module as part of a buildkernel to avoid potential problems like this. Thanks for helping get to the bottom of this and for the test feedback. Cheers, Lawrence