From owner-freebsd-current@FreeBSD.ORG Sun Sep 28 20:22:54 2014 Return-Path: Delivered-To: freebsd-current@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:1900:2254:206a::19:1]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by hub.freebsd.org (Postfix) with ESMTPS id 91B8E9B7 for ; Sun, 28 Sep 2014 20:22:54 +0000 (UTC) Received: from smtp1.multiplay.co.uk (smtp1.multiplay.co.uk [85.236.96.35]) by mx1.freebsd.org (Postfix) with ESMTP id 55A42132 for ; Sun, 28 Sep 2014 20:22:53 +0000 (UTC) Received: by smtp1.multiplay.co.uk (Postfix, from userid 65534) id A017620E7088F; Sun, 28 Sep 2014 20:13:53 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on smtp1.multiplay.co.uk X-Spam-Level: ** X-Spam-Status: No, score=2.2 required=8.0 tests=AWL,BAYES_00,DOS_OE_TO_MX, FSL_HELO_NON_FQDN_1,RDNS_DYNAMIC,STOX_REPLY_TYPE autolearn=no version=3.3.1 Received: from r2d2 (82-69-141-170.dsl.in-addr.zen.co.uk [82.69.141.170]) by smtp1.multiplay.co.uk (Postfix) with ESMTPS id BA08820E70885; Sun, 28 Sep 2014 20:13:51 +0000 (UTC) Message-ID: <58FFAD0C5E82494D9C52C891FE3A2728@multiplay.co.uk> From: "Steven Hartland" To: "Benjamin Kaduk" , =?UTF-8?Q?Jos=C3=A9_P=C3=A9rez_Arauzo?= References: <20140928071641.M7664@beckpeccoz.com> Subject: Re: What do you use for kernel debugging? Date: Sun, 28 Sep 2014 21:13:47 +0100 MIME-Version: 1.0 Content-Type: text/plain; format=flowed; charset="UTF-8"; reply-type=original Content-Transfer-Encoding: 8bit X-Priority: 3 X-MSMail-Priority: Normal X-Mailer: Microsoft Outlook Express 6.00.2900.5931 X-MimeOLE: Produced By Microsoft MimeOLE V6.00.2900.6157 Cc: FreeBSD Current X-BeenThere: freebsd-current@freebsd.org X-Mailman-Version: 2.1.18-1 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, 28 Sep 2014 20:22:54 -0000 ----- Original Message ----- From: "Benjamin Kaduk" To: "José Pérez Arauzo" Cc: "FreeBSD Current" Sent: Sunday, September 28, 2014 8:54 PM Subject: Re: What do you use for kernel debugging? > On Sun, 28 Sep 2014, José Pérez Arauzo wrote: > >> Hello, >> I am trying to track down a (deadlock?) issue in CURRENT via DDB. The kernel does >> not complete hw probes on my Acer V5. >> >> I get stuck on apic_isr looping which leads nowhere. >> >> So I thought maybe things improve if I debug from another machine. >> >> >> What do you use for kernel debugging? According to the handbook kgdb over serial >> is a good option, do you agree? I'm on a netbook with no ethernet and no option >> for firewire: can I have a USB / nullmodem setup to work? > > You cannot. > >> I have no old-style uarts hardware anymore, as the handbook suggests... >> >> Any idea is welcome before I buy extra hw. I have a USB to serial showing up as >> /dev/cuaU0, do I need to grab another one and a nullmodem cable or there are better >> alternatives? Thank you. > > I'm not sure that there are alternatives at all, unfortunately. > > You may be reduced to debugging-via-printf. dtrace can also be quite invaluable. Regards Steve