From owner-svn-src-all@FreeBSD.ORG Tue Sep 28 19:36:49 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 4DB1E1065693; Tue, 28 Sep 2010 19:36:49 +0000 (UTC) (envelope-from pjd@garage.freebsd.pl) Received: from mail.garage.freebsd.pl (60.wheelsystems.com [83.12.187.60]) by mx1.freebsd.org (Postfix) with ESMTP id A96BA8FC17; Tue, 28 Sep 2010 19:36:39 +0000 (UTC) Received: by mail.garage.freebsd.pl (Postfix, from userid 65534) id 8DDBF45C98; Tue, 28 Sep 2010 21:36:37 +0200 (CEST) Received: from localhost (chello089077043238.chello.pl [89.77.43.238]) (using TLSv1 with cipher DHE-RSA-AES256-SHA (256/256 bits)) (No client certificate requested) by mail.garage.freebsd.pl (Postfix) with ESMTP id D61A6456B1; Tue, 28 Sep 2010 21:36:31 +0200 (CEST) Date: Tue, 28 Sep 2010 21:36:11 +0200 From: Pawel Jakub Dawidek To: John Baldwin Message-ID: <20100928193611.GD2224@garage.freebsd.pl> References: <20100922222441.00002f27@unknown> <201009240923.04406.jhb@freebsd.org> <20100928183350.GB2224@garage.freebsd.pl> <201009281504.12236.jhb@freebsd.org> Mime-Version: 1.0 Content-Type: multipart/signed; micalg=pgp-sha1; protocol="application/pgp-signature"; boundary="0IvGJv3f9h+YhkrH" Content-Disposition: inline In-Reply-To: <201009281504.12236.jhb@freebsd.org> User-Agent: Mutt/1.4.2.3i X-PGP-Key-URL: http://people.freebsd.org/~pjd/pjd.asc X-OS: FreeBSD 9.0-CURRENT amd64 X-Spam-Checker-Version: SpamAssassin 3.0.4 (2005-06-05) on mail.garage.freebsd.pl X-Spam-Level: X-Spam-Status: No, score=-0.6 required=4.5 tests=BAYES_00,RCVD_IN_SORBS_DUL autolearn=no version=3.0.4 Cc: bruce@cran.org.uk, src-committers@freebsd.org, Ken Smith , svn-src-all@freebsd.org, avg@freebsd.org, gavin@freebsd.org, svn-src-head@freebsd.org, "M. Warner Losh" 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: Tue, 28 Sep 2010 19:36:49 -0000 --0IvGJv3f9h+YhkrH Content-Type: text/plain; charset=us-ascii Content-Disposition: inline Content-Transfer-Encoding: quoted-printable On Tue, Sep 28, 2010 at 03:04:11PM -0400, John Baldwin wrote: > > I am bigger fan of textdumps than minidumps, because in my opinion > > textdumps provide quite a lot of useful info. I'm working with FreeBSD > > kernel for years now and almost entirely avoided gdb for kernel > > debugging. DDB and printf(9) are in 99% enough for me (maybe I'm too > > traditional, but that's the fact). I'm not saying that textdumps are > > enough in 99%, though. >=20 > Have you looked at a /var/crash/core.txt.X file yet? If not, you should,= as > it is very similar to a text dump. In fact, it will contain the contents= of > any ddb trace buffer in addition to a stack trace from kgdb, process list= ing > from ps, etc. [...] > > Another important thing in my opinion is privacy of user's data. Once > > the data hit the disk it can stay there forever. This is why I use > > encrypted swap everywhere. I'd never send kernel minidump from my > > laptop or from any of my servers to anyone, but I'd be happy to send > > textdump. > >=20 > > I find textdumps a great solution that's in the middle between > > protecting user's privacy and providing a lot of useful info and I'd > > much prefer to turn on textdumps by default and eventually extend what > > we dump, than to make minidumps the default. >=20 > I'm suggesting they provide us the core.txt.X file, not the full minidump. > A developer could then ask them to run specific commands from a subsequent > kgdb session to obtain more details. But you still will have your kernel memory dumped to disk. This is probably not a problem for most of the users, though. > > You can always ask user to add this one-line to rc.conf to turn > > minidump on and provide you the info that was missing in textdump. >=20 > This only works for easily reproducible bugs, and in that case they can t= urn > on dumps later without a need for it to be automatic at all. And I'm arguing that those are very rare situations where there is a bug, which is hard to reproduce and where textdump won't be of any help. I'm aware that those are not strong arguments, but just worth taking into account, IMHO. --=20 Pawel Jakub Dawidek http://www.wheelsystems.com pjd@FreeBSD.org http://www.FreeBSD.org FreeBSD committer Am I Evil? Yes, I Am! --0IvGJv3f9h+YhkrH Content-Type: application/pgp-signature Content-Disposition: inline -----BEGIN PGP SIGNATURE----- Version: GnuPG v2.0.14 (FreeBSD) iEYEARECAAYFAkyiQ6sACgkQForvXbEpPzQghwCg1ez5WwJTA3HUe6ZVQ3nHWAfc qlkAn0dbFfmlVMg3e4qPTYkFi5pPn+6a =jCIE -----END PGP SIGNATURE----- --0IvGJv3f9h+YhkrH--