From owner-freebsd-arch@FreeBSD.ORG Tue Sep 21 15:38:24 2010 Return-Path: Delivered-To: arch@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:4f8:fff6::34]) by hub.freebsd.org (Postfix) with ESMTP id B84B710656AB for ; Tue, 21 Sep 2010 15:38:24 +0000 (UTC) (envelope-from avg@freebsd.org) Received: from citadel.icyb.net.ua (citadel.icyb.net.ua [212.40.38.140]) by mx1.freebsd.org (Postfix) with ESMTP id 10CE68FC1B for ; Tue, 21 Sep 2010 15:38:23 +0000 (UTC) Received: from odyssey.starpoint.kiev.ua (alpha-e.starpoint.kiev.ua [212.40.38.101]) by citadel.icyb.net.ua (8.8.8p3/ICyb-2.3exp) with ESMTP id SAA09089 for ; Tue, 21 Sep 2010 18:26:02 +0300 (EEST) (envelope-from avg@freebsd.org) Message-ID: <4C98CE89.7060908@freebsd.org> Date: Tue, 21 Sep 2010 18:26:01 +0300 From: Andriy Gapon User-Agent: Mozilla/5.0 (X11; U; FreeBSD amd64; en-US; rv:1.9.2.9) Gecko/20100920 Lightning/1.0b2 Thunderbird/3.1.4 MIME-Version: 1.0 To: arch@freebsd.org X-Enigmail-Version: 1.1.2 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit Cc: Subject: KDB, KDB_TRACE in GENERICs for stable/X X-BeenThere: freebsd-arch@freebsd.org X-Mailman-Version: 2.1.5 Precedence: list List-Id: Discussion related to FreeBSD architecture List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Tue, 21 Sep 2010 15:38:24 -0000 I would like to propose to add KDB and KDB_TRACE options to GENERIC kernel configurations on stable branches. I've verified that without any other KDB-related options and without any backend configured these options do not change any aspect of system behavior. Any attempts to enter debugger are ignored; on panic a panic message is printed and system reboots after that. With the proposed options and MFC of r212964 we should be able to get a backtrace printed in addition to a standard panic message. This may help us in analyzing problems during initial system installation and for systems that keep using GENERIC after installation for various reasons. This is especially true for panics that result from traps like page fault in which case we don't have much information on cause of a trap. Presence of the proposed options in GENERIC should not affect those who include GENERIC into their own configuration files for further extension and/or trimming. What do you think? -- Andriy Gapon