From owner-svn-src-all@FreeBSD.ORG Wed Sep 22 15:23:42 2010 Return-Path: Delivered-To: svn-src-all@FreeBSD.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:4f8:fff6::34]) by hub.freebsd.org (Postfix) with ESMTP id 57910106566C; Wed, 22 Sep 2010 15:23:42 +0000 (UTC) (envelope-from gavin@FreeBSD.org) Received: from gse-mta-27.emailfiltering.com (gse-mta-27-tx.emailfiltering.com [194.116.198.158]) by mx1.freebsd.org (Postfix) with ESMTP id EA8FF8FC12; Wed, 22 Sep 2010 15:23:40 +0000 (UTC) Received: from mail-gw5.york.ac.uk ([144.32.129.29]) by gse-mta-27.emailfiltering.com with emfmta (version 4.6.0.72) by TLS id 753660736 for avg@FreeBSD.org;792989edab745909; Wed, 22 Sep 2010 16:23:39 +0100 Received: from buffy-128.york.ac.uk ([144.32.128.160]:40427 helo=buffy.york.ac.uk) by mail-gw5.york.ac.uk with esmtps (TLS1.0:DHE_RSA_AES_256_CBC_SHA1:32) (Exim 4.71) (envelope-from ) id 1OyRAY-0007xB-2C; Wed, 22 Sep 2010 16:23:38 +0100 Received: from buffy.york.ac.uk (localhost [127.0.0.1]) by buffy.york.ac.uk (8.14.4/8.14.4) with ESMTP id o8MFNbpo064768; Wed, 22 Sep 2010 16:23:37 +0100 (BST) (envelope-from gavin@FreeBSD.org) Received: (from ga9@localhost) by buffy.york.ac.uk (8.14.4/8.14.4/Submit) id o8MFNb4v064767; Wed, 22 Sep 2010 16:23:37 +0100 (BST) (envelope-from gavin@FreeBSD.org) X-Authentication-Warning: buffy.york.ac.uk: ga9 set sender to gavin@FreeBSD.org using -f From: Gavin Atkinson To: Andriy Gapon In-Reply-To: <4C9A1602.4020204@freebsd.org> References: <201009211507.o8LF7iVv097676@svn.freebsd.org> <1285163200.64197.10.camel@buffy.york.ac.uk> <4C9A1602.4020204@freebsd.org> Content-Type: text/plain; charset="ASCII" Content-Transfer-Encoding: quoted-printable Date: Wed, 22 Sep 2010 16:23:37 +0100 Message-ID: <1285169017.64197.29.camel@buffy.york.ac.uk> Mime-Version: 1.0 X-Mailer: Evolution 2.30.1.2 FreeBSD GNOME Team Port Cc: svn-src-head@FreeBSD.org, svn-src-all@FreeBSD.org, src-committers@FreeBSD.org Subject: Re: svn commit: r212964 - head/sys/kern X-BeenThere: svn-src-all@freebsd.org X-Mailman-Version: 2.1.5 Precedence: list List-Id: "SVN commit messages for the entire src tree \(except for " user" and " projects" \)" List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Wed, 22 Sep 2010 15:23:42 -0000 On Wed, 2010-09-22 at 17:43 +0300, Andriy Gapon wrote: > on 22/09/2010 16:46 Gavin Atkinson said the following: > > Ignoring the rest of the discussion about locking, I think this is a > > step in the right direction. However, what I feel we should be strongl= y > > considering is for textdumps to be enabled by default on release media. > >=20 > > As more groups choose to use the kernels from the release media (PC-BSD= , > > FreeNAS, etc) and put them into places where end users are never > > expected to recompile kernels, having textdumps enabled by default in > > RELEASE kernels becomes a bigger and bigger priority. Groups like > > PC-BSD don't necessarily have the time or skills to do the needed kerne= l > > debugging (and nor should they have to, it's not their purpose), so > > anything we can do in releases to make sure we have enough info to > > resolve panics seen by their users is a big bonus. > >=20 > > Is there any real reason why we shouldn't go down this route? >=20 > textdumps need DDB. > textdumps also need dumpdev which is not enabled by default in > /etc/defaults/rc.conf, but that's easier to fix for any individual user o= r a > FreeBSD "distribution". Indeed, I was happy to see dumpdev enabled on 7.x, and disappointed to see it disabled on 8.x. > I originally suggested to include DDB in the stable GENERICs. > But that has a number of consequences: > 1. With DDB a panic results in a system going to ddb prompt instead of re= booting, > unless KDB_UNATTENDED is also specified. System not rebooting on panic m= ay be a > POLA violation and an inconvenience. However, a user can change this usi= ng > debug.debugger_on_panic=3D0 sysctl. Although, sysctl time might be too l= ate in some > cases, not sure. Indeed, if we went down this route we would have to make sure that the existing behaviour of rebooting is preserved. We'd also have to ensure Ctrl-Alt-Escape doesn't drop to the debugger on release media. > For me personally, the significant benefits outweigh possible minor/tempo= rary > inconveniences and surprises, but this opinion is not shared by all devel= opers. I (and I suspect any of the other people on the PR database frontline) would probably support this :) > Really besides the point, but such FreeBSD "distributions" like FreeNAS a= nd PC-BSD > can really use their own kernel config, they don't have to use the same G= ENERICs. Indeed, although in some ways they shouldn't have to. Having textdumps enabled by default would also be a huge win for us, of course. > P.S. I think that it would have been better if you followed up to my prop= osal on > arch@. I'm not subscribed to -arch at the moment, I probably should be. I guess you're talking about the thread in June? I wish I'd seen that at the time, I'm 100% in favour of it. Gavin --=20 Gavin Atkinson FreeBSD committer and bugmeister GPG: A093262B (313A A79F 697D 3A5C 216A EDF5 935D EF44 A093 262B)