From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751762AbdKJJnb (ORCPT ); Fri, 10 Nov 2017 04:43:31 -0500 Received: from mx1.redhat.com ([209.132.183.28]:54414 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751078AbdKJJn2 (ORCPT ); Fri, 10 Nov 2017 04:43:28 -0500 Date: Fri, 10 Nov 2017 10:43:25 +0100 From: Jiri Olsa To: Arnaldo Carvalho de Melo Cc: Jiri Olsa , lkml , Ingo Molnar , Namhyung Kim , David Ahern , Peter Zijlstra Subject: Re: [PATCH 2/3] perf tools: Fix build for hardened environments Message-ID: <20171110094325.GA18088@krava> References: <20171108102739.30338-1-jolsa@kernel.org> <20171108102739.30338-3-jolsa@kernel.org> <20171108160321.GC4333@kernel.org> <20171109073622.GB14419@krava> <20171109125212.GG4333@kernel.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20171109125212.GG4333@kernel.org> User-Agent: Mutt/1.9.1 (2017-09-22) X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.5.16 (mx1.redhat.com [10.5.110.38]); Fri, 10 Nov 2017 09:43:27 +0000 (UTC) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Thu, Nov 09, 2017 at 09:52:12AM -0300, Arnaldo Carvalho de Melo wrote: > Em Thu, Nov 09, 2017 at 08:36:22AM +0100, Jiri Olsa escreveu: > > On Wed, Nov 08, 2017 at 01:03:21PM -0300, Arnaldo Carvalho de Melo wrote: > > > Em Wed, Nov 08, 2017 at 11:27:38AM +0100, Jiri Olsa escreveu: > > > > From: Jiri Olsa > > > > > > > > On Fedora systems the perl and python CFLAGS/LDFLAGS include the > > > > hardened specs from redhat-rpm-config package. We apply them only > > > > for perl/python objects, which makes them not compatible with the > > > > rest of the objects and the build fails with: > > > > > > > > /usr/bin/ld: perf-in.o: relocation R_X86_64_32 against `.rodata.str1.1' can not be used when making a shared object; recompile with -fPIC > > > > /usr/bin/ld: libperf.a(libperf-in.o): relocation R_X86_64_32S against `.text' can not be used when making a shared object; recompile with -fPIC > > > > /usr/bin/ld: final link failed: Nonrepresentable section on output > > > > collect2: error: ld returned 1 exit status > > > > make[2]: *** [Makefile.perf:507: perf] Error 1 > > > > make[1]: *** [Makefile.perf:210: sub-make] Error 2 > > > > make: *** [Makefile:69: all] Error 2 > > > > > > > > Mainly it's caused by perl/python objects being compiled with: > > > > > > > > -specs=/usr/lib/rpm/redhat/redhat-hardened-cc1 > > > > > > > > which prevent the final link impossible, because it will check > > > > for 'proper' objects with following option: > > > > > > > > -specs=/usr/lib/rpm/redhat/redhat-hardened-ld > > > > > > > > Fixing this by using the perl/python CFLAGS/LDFLAGS options > > > > for all the objects. > > > > > > Humm, so we're basically using the hardened config only we build with > > > PERL or PYTHON, should we use that always, i.e. ask the distro what set > > > of flags we should use? > > > > right, I think this needs to be detected like we do for features, > > since there maybe some supported gcc versions to detect > > Right, since we want to honour what the distro makers decided was the > best set for them, and to be able to link with other libraries, etc. > > But then I think this should be done more explicitely, right? Do you > envision some way to do that without having to try to build perl or > python, that may not be installed, etc? > I'll check on it.. I think we could use feature detection and enable that by default and add NO_HARDENED_BUILD variable as we do for features.. and detect that python/perl or whatever else is using that and warn > Of course users wanting to use something different may just set CFLAGS > and be done with it, in which case I think this should also affect the > perl and python CFLAGS, removing that distro specific stuff since the > user is changing something different. yep jirka