From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (qmail 4464 invoked by alias); 10 Nov 2009 09:35:39 -0000 Received: (qmail 4436 invoked by uid 22791); 10 Nov 2009 09:35:37 -0000 X-SWARE-Spam-Status: No, hits=-2.4 required=5.0 tests=AWL,BAYES_00,SPF_HELO_PASS,SPF_PASS X-Spam-Check-By: sourceware.org Received: from smtp2.tu-cottbus.de (HELO smtp2.tu-cottbus.de) (141.43.99.248) by sourceware.org (qpsmtpd/0.43rc1) with ESMTP; Tue, 10 Nov 2009 09:35:32 +0000 Received: from localhost (localhost.localdomain [127.0.0.1]) by smtp2.tu-cottbus.de (Postfix) with ESMTP id B31C6690139; Tue, 10 Nov 2009 10:35:29 +0100 (CET) Received: from loki (cd1.cd.tu-cottbus.de [141.43.159.77]) (using TLSv1 with cipher DHE-RSA-AES256-SHA (256/256 bits)) (Client did not present a certificate) by smtp2.tu-cottbus.de (Postfix) with ESMTPSA id E0F606901B5; Tue, 10 Nov 2009 10:33:11 +0100 (CET) Received: by loki (Postfix, from userid 1000) id 433A9EAA140; Tue, 10 Nov 2009 10:32:55 +0100 (CET) Date: Tue, 10 Nov 2009 09:35:00 -0000 From: Eugeniy Meshcheryakov To: James Y Knight Cc: systemtap@sourceware.org Subject: Re: Troubles with debug info, using systemtap on debian. Message-ID: <20091110093254.GA3190@localhost.localdomain> References: MIME-Version: 1.0 Content-Type: multipart/signed; micalg=pgp-sha1; protocol="application/pgp-signature"; boundary="5vNYLRcllDrimb99" Content-Disposition: inline In-Reply-To: User-Agent: Mutt/1.5.20 (2009-06-14) Mailing-List: contact systemtap-help@sourceware.org; run by ezmlm Precedence: bulk List-Id: List-Subscribe: List-Post: List-Help: , Sender: systemtap-owner@sourceware.org X-SW-Source: 2009-q4/txt/msg00479.txt.bz2 --5vNYLRcllDrimb99 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline Content-Transfer-Encoding: quoted-printable Content-length: 2804 Hello, 9 =D0=BB=D0=B8=D1=81=D1=82=D0=BE=D0=BF=D0=B0=D0=B4=D0=B0 2009 =D0=BE 20:18 = -0500 James Y Knight =D0=BD=D0=B0=D0=BF=D0=B8=D1=81=D0=B0=D0=B2(-=D0=BB=D0= =B0): > Systemtap was working fine, for symbols in vmlinux, but segfaulted > when trying to probe modules. E.g., the simplest script segfaulted > in the translator. >=20 > probe module("autofs4").function("autofs4_fill_super") {} I never saw systemtap segfaulting. I do not have autofs4 module, but i tried with snd module and it works. What version of systemtap/libelf1/libdw1 do you use? > debug package. Well, that failed, because the files there are > apparently expected to be called: *.ko.debug, but I had a file > called: > /usr/lib/debug/lib/modules/2.6.31-jknight-1-amd64/kernel/fs/autofs4/ > autofs4.ko > instead. So, I symlinked it to be called autofs4.ko.debug. My bad, I rarely clean the build tree... Still I do not understand why this .debug is needed... I'm going to ask kernel-package or elfutils maintainers to change this... > 3) The debian kernel's debuginfo does "objcopy --only-keep- > debug"...That seems like it shouldn't cause systemtap to blow up, > but it does. I guess that's a known bug? No it is not. At least not for me. > 4) Why does it blow up *differently* depending on whether it found > the file in /usr/lib/debug or /lib/modules? >=20 > 5) Whose bug is it that systemtap doesn't look for > /usr/lib/debug/.../autofs4.ko, but only autofs4.ko.debug? > Apparently this is a difference between debian and Fedora. Fedora > systems append .debug, Debian systems do not. My guess: debian > should be patching their copy of elfutils to not append ".debug"? > But maybe that's an upstream bug, and it should try both by default > (or something). > I dunno. Me too. >=20 > Someone else discovered the ".debug" issue in another program: > http://www.visophyte.org/rev_control/patches/chronicle-recorder/debian-us= r-lib-debug-support.patch > And here's the debian reference about how to install debuginfo: > http://www.debian.org/doc/developers-reference/best-pkging-practices.html= #bpp-dbg If it is really Fedors's policy to append .debug to file names under /usr/lib/debug (I did not know about that), then I guess Debian elfutils should be modified to not append .debug to kernel modules names to comply with Debian policy. Or hopefuly it can be done upstream. >=20 >=20 > I guess all these except the first are probably bugs in elfutils, > not systemtap, so perhaps I should be reporting it there instead. > But despite what you might think, I actually have no clue about any > of this crap: any clue you might infer from the above has all been > gained by random flailing over the course of the last couple hours. > So I figure it's safer to report here, first and redirect if > requested. :) >=20 > James --5vNYLRcllDrimb99 Content-Type: application/pgp-signature; name="signature.asc" Content-Description: Digital signature Content-Disposition: inline Content-length: 198 -----BEGIN PGP SIGNATURE----- Version: GnuPG v1.4.10 (GNU/Linux) iEYEARECAAYFAkr5M0YACgkQKaC6+zmozOLhAACfYeB+wzLLKmOHbVUW4dMOek19 fJ0AnA6G4wjvKFAKm7AbE/l8o1URnwJv =wxyb -----END PGP SIGNATURE----- --5vNYLRcllDrimb99--