From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754137AbcESIsH (ORCPT ); Thu, 19 May 2016 04:48:07 -0400 Received: from r00tworld.com ([212.85.137.150]:59874 "EHLO r00tworld.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754054AbcESIsE (ORCPT ); Thu, 19 May 2016 04:48:04 -0400 X-Greylist: delayed 1360 seconds by postgrey-1.27 at vger.kernel.org; Thu, 19 May 2016 04:48:04 EDT From: "PaX Team" To: Emese Revfy , kernel-hardening@lists.openwall.com, Michael Ellerman Date: Thu, 19 May 2016 10:24:13 +0200 MIME-Version: 1.0 Subject: Re: [kernel-hardening] [PATCH v8 2/4] GCC plugin infrastructure Reply-to: pageexec@freemail.hu CC: Andrew Donnellan , linux-kbuild@vger.kernel.org, spender@grsecurity.net, mmarek@suse.com, keescook@chromium.org, linux@rasmusvillemoes.dk, fengguang.wu@intel.com, dvyukov@google.com, linux-kernel@vger.kernel.org, david.brown@linaro.org, yamada.masahiro@socionext.com, linuxppc-dev , Daniel Axtens Message-ID: <573D782D.10392.75A275C@pageexec.freemail.hu> In-reply-to: <1463638931.10451.10.camel@ellerman.id.au> References: <20160513015456.01415979f20a68eb7d2d9290@gmail.com>, <20160518123327.9018f73af78a47b4456b2027@gmail.com>, <1463638931.10451.10.camel@ellerman.id.au> X-mailer: Pegasus Mail for Windows (4.72.572) Content-type: text/plain; charset=US-ASCII Content-transfer-encoding: 7BIT Content-description: Mail message body X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-2.1.12 (r00tworld.com [212.85.137.150]); Thu, 19 May 2016 10:24:16 +0200 (CEST) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 19 May 2016 at 16:22, Michael Ellerman wrote: > On Wed, 2016-05-18 at 12:33 +0200, Emese Revfy wrote: > > Did you test the plugins with all gcc versions (4.5-6)? > > What's the concern about gcc versions? Just not breaking the build on old > compilers? the earlier plugin capable gcc versions used to install gcc headers in a somewhat ad-hoc manner resulting in compile time breakage for plugins and since some of those potentially missing headers are target specific, each target arch should be verified before enabling plugin support on them. things have much improved with gcc 5 (see https://gcc.gnu.org/bugzilla/show_bug.cgi?id=61176) though there's still an occasional missing header but with wider use of plugins they will hopefully be discovered earlier now. perhaps linux-arch should be cc'ed on the plugin infrastructure so that arch maintainers are aware of this? > I'm pretty sure powerpc big endian still builds with gcc 4.4. > > However if Andrew's only tested on little endian, then that select should be > guarded with an "if CPU_LITTLE_ENDIAN". And to build LE you need gcc >= 4.9. i guess that's part of the target tuple so in general arch maintainers should test the target tuples used on their arch with all the supported gcc versions (speaking of CC, not HOSTCC/HOSTCXX). cheers, PaX Team