From owner-freebsd-current@FreeBSD.ORG Sun Dec 10 08:42:36 2006 Return-Path: X-Original-To: freebsd-current@FreeBSD.org Delivered-To: freebsd-current@FreeBSD.org Received: from mx1.FreeBSD.org (mx1.freebsd.org [69.147.83.52]) by hub.freebsd.org (Postfix) with ESMTP id 3AFEC16A407 for ; Sun, 10 Dec 2006 08:42:36 +0000 (UTC) (envelope-from rwatson@FreeBSD.org) Received: from cyrus.watson.org (cyrus.watson.org [209.31.154.42]) by mx1.FreeBSD.org (Postfix) with ESMTP id DB05543C9E for ; Sun, 10 Dec 2006 08:41:26 +0000 (GMT) (envelope-from rwatson@FreeBSD.org) Received: from fledge.watson.org (fledge.watson.org [209.31.154.41]) by cyrus.watson.org (Postfix) with ESMTP id 8FBD046B0A; Sun, 10 Dec 2006 03:42:35 -0500 (EST) Date: Sun, 10 Dec 2006 08:42:35 +0000 (GMT) From: Robert Watson X-X-Sender: robert@fledge.watson.org To: Maxim Konovalov In-Reply-To: <20061210013735.D11309@mp2.macomnet.net> Message-ID: <20061210083752.G9926@fledge.watson.org> References: <52944.192.168.1.110.1165679313.squirrel@yal.hopto.org> <20061209195519.B60055@mp2.macomnet.net> <20061209204924.N9926@fledge.watson.org> <20061210013735.D11309@mp2.macomnet.net> MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII; format=flowed Cc: freebsd-current@FreeBSD.org, yal Subject: Re: CURRENT freezes on Laitude D520 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: Sun, 10 Dec 2006 08:42:36 -0000 On Sun, 10 Dec 2006, Maxim Konovalov wrote: >> Do you have any information about the actual source of this problem? > > No, I don't. The whole system is unstable. E.g. ifconfig hangs at the > random time. Wireless stops working, mouse is lagging. Suddenly the whole > system just hangs. > > yal@ replied in the private email debug.mpsafenet="0" did help him too. > >> Would it motivate solving the problem if I were to remove the >> debug.mpsafenet tunable? :-) > > I didn't suggest to turn off mpsafenet forever and forget, I just wanted to > check my guess. I would like to help to debug the problem but I need some > initial instructions to start. There is a firewire console. What do I need > to check? Start with the information in my followup e-mail to Andrew: - Configure WITNESS and see if you get any console output regarding lock order problems. - Try setting net.isr.direct=0 and see if the problem goes away. - Try removing options PREEMPTION and see if the problem goes away. Don't try them all at once, rather, try them individually until you've managed to find some arrangement that makes the source of the problem more clear (i.e., a WITNESS warning involving, say, the network stack). When suggesting debug.mpsafenet=0 as a debugging step, please make it clear that this is not a solution. The hope is that in 7.0, all components of the network stack will be MPSAFE, so whether in the short or long term, it is going away, and workarounds masking the problem don't get us any closer to solving the problem. Robert N M Watson Computer Laboratory University of Cambridge