From mboxrd@z Thu Jan 1 00:00:00 1970 From: Florian Weimer Subject: Re: [PATCH v7 22/27] binfmt_elf: Extract .note.gnu.property from an ELF file Date: Tue, 18 Jun 2019 14:47:00 +0200 Message-ID: <87ef3r9i2j.fsf@oldenburg2.str.redhat.com> References: <20190606200646.3951-23-yu-cheng.yu@intel.com> <20190607180115.GJ28398@e103592.cambridge.arm.com> <94b9c55b3b874825fda485af40ab2a6bc3dad171.camel@intel.com> <87lfy9cq04.fsf@oldenburg2.str.redhat.com> <20190611114109.GN28398@e103592.cambridge.arm.com> <031bc55d8dcdcf4f031e6ff27c33fd52c61d33a5.camel@intel.com> <20190612093238.GQ28398@e103592.cambridge.arm.com> <87imt4jwpt.fsf@oldenburg2.str.redhat.com> <20190618091248.GB2790@e103592.cambridge.arm.com> <20190618124122.GH3419@hirez.programming.kicks-ass.net> Mime-Version: 1.0 Content-Type: text/plain Return-path: In-Reply-To: <20190618124122.GH3419@hirez.programming.kicks-ass.net> (Peter Zijlstra's message of "Tue, 18 Jun 2019 14:41:22 +0200") Sender: linux-kernel-owner@vger.kernel.org To: Peter Zijlstra Cc: Dave Martin , Thomas Gleixner , Yu-cheng Yu , x86@kernel.org, "H. Peter Anvin" , Ingo Molnar , linux-kernel@vger.kernel.org, linux-doc@vger.kernel.org, linux-mm@kvack.org, linux-arch@vger.kernel.org, linux-api@vger.kernel.org, Arnd Bergmann , Andy Lutomirski , Balbir Singh , Borislav Petkov , Cyrill Gorcunov , Dave Hansen , Eugene Syromiatnikov , "H.J. Lu" , Jann Horn , Jonathan Corbet , Kees Cook , Mike Kravetz , Nad List-Id: linux-arch.vger.kernel.org * Peter Zijlstra: > I'm not sure I read Thomas' comment like that. In my reading keeping the > PT_NOTE fallback is exactly one of those 'fly workarounds'. By not > supporting PT_NOTE only the 'fine' people already shit^Hpping this out > of tree are affected, and we don't have to care about them at all. Just to be clear here: There was an ABI document that required PT_NOTE parsing. The Linux kernel does *not* define the x86-64 ABI, it only implements it. The authoritative source should be the ABI document. In this particularly case, so far anyone implementing this ABI extension tried to provide value by changing it, sometimes successfully. Which makes me wonder why we even bother to mainatain ABI documentation. The kernel is just very late to the party. Thanks, Florian From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mx1.redhat.com ([209.132.183.28]:63683 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725913AbfFRMrS (ORCPT ); Tue, 18 Jun 2019 08:47:18 -0400 From: Florian Weimer Subject: Re: [PATCH v7 22/27] binfmt_elf: Extract .note.gnu.property from an ELF file References: <20190606200646.3951-23-yu-cheng.yu@intel.com> <20190607180115.GJ28398@e103592.cambridge.arm.com> <94b9c55b3b874825fda485af40ab2a6bc3dad171.camel@intel.com> <87lfy9cq04.fsf@oldenburg2.str.redhat.com> <20190611114109.GN28398@e103592.cambridge.arm.com> <031bc55d8dcdcf4f031e6ff27c33fd52c61d33a5.camel@intel.com> <20190612093238.GQ28398@e103592.cambridge.arm.com> <87imt4jwpt.fsf@oldenburg2.str.redhat.com> <20190618091248.GB2790@e103592.cambridge.arm.com> <20190618124122.GH3419@hirez.programming.kicks-ass.net> Date: Tue, 18 Jun 2019 14:47:00 +0200 In-Reply-To: <20190618124122.GH3419@hirez.programming.kicks-ass.net> (Peter Zijlstra's message of "Tue, 18 Jun 2019 14:41:22 +0200") Message-ID: <87ef3r9i2j.fsf@oldenburg2.str.redhat.com> MIME-Version: 1.0 Content-Type: text/plain Sender: linux-arch-owner@vger.kernel.org List-ID: To: Peter Zijlstra Cc: Dave Martin , Thomas Gleixner , Yu-cheng Yu , x86@kernel.org, "H. Peter Anvin" , Ingo Molnar , linux-kernel@vger.kernel.org, linux-doc@vger.kernel.org, linux-mm@kvack.org, linux-arch@vger.kernel.org, linux-api@vger.kernel.org, Arnd Bergmann , Andy Lutomirski , Balbir Singh , Borislav Petkov , Cyrill Gorcunov , Dave Hansen , Eugene Syromiatnikov , "H.J. Lu" , Jann Horn , Jonathan Corbet , Kees Cook , Mike Kravetz , Nadav Amit , Oleg Nesterov , Pavel Machek , Randy Dunlap , "Ravi V. Shankar" , Vedvyas Shanbhogue Message-ID: <20190618124700.o4pEPsOagLy2ml-LTis26QmgJEdtIkE39iB4yBjjyic@z> * Peter Zijlstra: > I'm not sure I read Thomas' comment like that. In my reading keeping the > PT_NOTE fallback is exactly one of those 'fly workarounds'. By not > supporting PT_NOTE only the 'fine' people already shit^Hpping this out > of tree are affected, and we don't have to care about them at all. Just to be clear here: There was an ABI document that required PT_NOTE parsing. The Linux kernel does *not* define the x86-64 ABI, it only implements it. The authoritative source should be the ABI document. In this particularly case, so far anyone implementing this ABI extension tried to provide value by changing it, sometimes successfully. Which makes me wonder why we even bother to mainatain ABI documentation. The kernel is just very late to the party. Thanks, Florian