From owner-freebsd-hackers@FreeBSD.ORG Tue May 26 14:00:51 2009 Return-Path: Delivered-To: freebsd-hackers@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:4f8:fff6::34]) by hub.freebsd.org (Postfix) with ESMTP id 9B1281065670 for ; Tue, 26 May 2009 14:00:51 +0000 (UTC) (envelope-from fhcarron@terra.es) Received: from IMPaqm4.telefonica.net (impaqm4.telefonica.net [213.4.129.19]) by mx1.freebsd.org (Postfix) with ESMTP id 0AB428FC08 for ; Tue, 26 May 2009 14:00:50 +0000 (UTC) (envelope-from fhcarron@terra.es) Received: from IMPmailhost1.adm.correo ([10.20.102.38]) by IMPaqm4.telefonica.net with bizsmtp id wD2k1b00G0piX6q3QDqoNd; Tue, 26 May 2009 15:50:48 +0200 Received: from [150.244.58.19] ([150.244.58.19]) by IMPmailhost1.adm.correo with BIZ IMP id wDqn1b00H0Qtfg61hDqo0b; Tue, 26 May 2009 15:50:48 +0200 X-TE-authinfo: authemail="fhcarron.terra.es" |auth_email="fhcarron@terra.es" X-TE-AcuTerraCos: auth_cuTerraCos="cosuiterc01" From: Fernando Herrero =?ISO-8859-1?Q?Carr=F3n?= To: freebsd-hackers@freebsd.org Content-Type: text/plain Date: Tue, 26 May 2009 15:50:47 +0200 Message-Id: <1243345847.1007.11.camel@nebet.ii.uam.es> Mime-Version: 1.0 X-Mailer: Evolution 2.26.0 FreeBSD GNOME Team Port Content-Transfer-Encoding: 7bit Subject: Help debugging kernel together with X X-BeenThere: freebsd-hackers@freebsd.org X-Mailman-Version: 2.1.5 Precedence: list List-Id: Technical Discussions relating to FreeBSD List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Tue, 26 May 2009 14:00:52 -0000 Hi list, I would like to ask for some help debugging the kernel. Here is the problem: I have a computer about five years old with an on-board graphics card (SiS 661). I am trying to install an ATI Radeon 128 on the AGP port. FreeBSD (FreeBSD 7.2-STABLE #10: Tue May 26 15:08:39 CEST 2009) is able to start DRM and AGP without trouble. However, whenever I start X (X.Org X Server 1.6.1; Release Date: 2009-4-14; Build Date: 11 May 2009 12:03:27PM) the system freezes with a blank screen with some apparent noisy green dots on it (reproducible, however). It does not panic, nor reboot. Now I suspect there is some problem on the AGP bridge driver since linux can run X without trouble (i.e. hardware and BIOS are ok). I have found someone reporting problems with this bridge long time ago with no answers (http://www.nabble.com/agp-on-sis-661-td1446998.html). So here I am trying to figure out where the system freezes. I have recompiled my kernel adding the following options: options KDB options DDB options MP_WATCHDOG options SW_WATCHDOG I am able to enter the debugger with ctrl+alt+esc from a console. So what I am trying to do is to have watchdogd time out and the debugger make a dump: ddb script kern.enter.watchdog=call doadump; reboot However, when I start X no timeout occurs, and the system stays freezed. Am I missing something on the workings of watchdogd? Thanks a lot for your help! Fernando