From owner-freebsd-current@FreeBSD.ORG Mon Feb 23 21:18:06 2009 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 84377106564A for ; Mon, 23 Feb 2009 21:18:06 +0000 (UTC) (envelope-from jhb@freebsd.org) Received: from cyrus.watson.org (cyrus.watson.org [65.122.17.42]) by mx1.freebsd.org (Postfix) with ESMTP id 514EA8FC08 for ; Mon, 23 Feb 2009 21:18:06 +0000 (UTC) (envelope-from jhb@freebsd.org) Received: from server.baldwin.cx (pool-98-109-39-197.nwrknj.fios.verizon.net [98.109.39.197]) by cyrus.watson.org (Postfix) with ESMTPSA id BA1FA46B09; Mon, 23 Feb 2009 16:18:05 -0500 (EST) Received: from localhost (john@localhost [127.0.0.1]) (authenticated bits=0) by server.baldwin.cx (8.14.3/8.14.3) with ESMTP id n1NLHxxH018426; Mon, 23 Feb 2009 16:17:59 -0500 (EST) (envelope-from jhb@freebsd.org) From: John Baldwin To: "David Christensen" Date: Mon, 23 Feb 2009 16:17:53 -0500 User-Agent: KMail/1.9.7 References: <5D267A3F22FD854F8F48B3D2B5238193394588D54D@IRVEXCHCCR01.corp.ad.broadcom.com> <200902231257.28060.jhb@freebsd.org> <5D267A3F22FD854F8F48B3D2B52381933950E91B04@IRVEXCHCCR01.corp.ad.broadcom.com> In-Reply-To: <5D267A3F22FD854F8F48B3D2B52381933950E91B04@IRVEXCHCCR01.corp.ad.broadcom.com> MIME-Version: 1.0 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: 7bit Content-Disposition: inline Message-Id: <200902231617.54340.jhb@freebsd.org> X-Greylist: Sender succeeded SMTP AUTH authentication, not delayed by milter-greylist-2.0.2 (server.baldwin.cx [127.0.0.1]); Mon, 23 Feb 2009 16:17:59 -0500 (EST) X-Virus-Scanned: ClamAV 0.94.2/9034/Mon Feb 23 12:41:23 2009 on server.baldwin.cx X-Virus-Status: Clean X-Spam-Status: No, score=-4.4 required=4.2 tests=ALL_TRUSTED,AWL,BAYES_00 autolearn=ham version=3.1.3 X-Spam-Checker-Version: SpamAssassin 3.1.3 (2006-06-01) on server.baldwin.cx Cc: "freebsd-current@freebsd.org" Subject: Re: Hopefully Simple Question on Debugging Kernel Modules 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: Mon, 23 Feb 2009 21:18:06 -0000 On Monday 23 February 2009 3:51:18 pm David Christensen wrote: > > > > Just use gdb on bce.ko (built with debug symbols): > > > > > > > > gdb /path/to/if_bce.ko > > > > (gdb) l *bce_intr+0x8df > > > > > > > > If you get a crashdump you can run kgdb on it and just walk up to > > the > > relevant > > > > stack frame and use 'l' there to get a listing. > > > > > > > > > > One thing that I've never figured out is how debugging symbols are > > > handled in module builds these days. If I go to /sys/modules/bce and > > > do 'make', it generates a .ko and explicitly strips it. I wind up > > > having to re-run the link command by hand so I get symbols. What is > > > the correct way to do this? Note that I'm not interested in answers > > > that involve "go to /usr/src and run make buildkernel" =-) > > > > make DEBUG_FLAGS=-g is what I use. The same thing works for userland > > tools > > and the kernel (usually we put 'makeoptions DEBUG_FLAGS=-g' in a kernel > > config so it is "automatic" for kernels though). > > So is the use of COPTS=-g mentioned in the Developer's Handbook > (http://www.freebsd.org/doc/en/books/developers-handbook/kerneldebug-kld.html) > deprecated? I wasn't able to build with symbols until I used DEBUG_FLAGS='g. Yes. kgdb is now also smarter in that it should automatically load symbols for kld's. There's no need to use add-symbol-file to add symbols by hand anymore. -- John Baldwin