From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-3.8 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_PASS autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id BEB8FC32788 for ; Thu, 11 Oct 2018 14:23:11 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 7F91620652 for ; Thu, 11 Oct 2018 14:23:11 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 7F91620652 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=arm.com Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728554AbeJKVue (ORCPT ); Thu, 11 Oct 2018 17:50:34 -0400 Received: from foss.arm.com ([217.140.101.70]:38318 "EHLO foss.arm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726537AbeJKVue (ORCPT ); Thu, 11 Oct 2018 17:50:34 -0400 Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.72.51.249]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id 8BD94EBD; Thu, 11 Oct 2018 07:23:09 -0700 (PDT) Received: from [10.1.214.49] (unknown [10.1.214.49]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id B41393F5B3; Thu, 11 Oct 2018 07:23:06 -0700 (PDT) Subject: Re: [RFC 17/17] arm64: compile the kernel with ptrauth -msign-return-address To: Kristina Martsenko , linux-arm-kernel@lists.infradead.org Cc: linux-arch@vger.kernel.org, Jacob Bramley , Arnd Bergmann , Ard Biesheuvel , Marc Zyngier , Catalin Marinas , Adam Wallis , Will Deacon , kvmarm@lists.cs.columbia.edu, Ramana Radhakrishnan , Amit Kachhap , Dave P Martin , linux-kernel@vger.kernel.org, Kees Cook References: <20181005084754.20950-1-kristina.martsenko@arm.com> <20181005084754.20950-18-kristina.martsenko@arm.com> From: Vladimir Murzin Message-ID: Date: Thu, 11 Oct 2018 15:23:05 +0100 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:52.0) Gecko/20100101 Thunderbird/52.9.1 MIME-Version: 1.0 In-Reply-To: <20181005084754.20950-18-kristina.martsenko@arm.com> Content-Type: text/plain; charset=utf-8 Content-Language: en-US Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hi Kristina, On 05/10/18 09:47, Kristina Martsenko wrote: > diff --git a/arch/arm64/Makefile b/arch/arm64/Makefile > index 106039d25e2f..dbcd43ea99d8 100644 > --- a/arch/arm64/Makefile > +++ b/arch/arm64/Makefile > @@ -56,6 +56,10 @@ KBUILD_AFLAGS += $(lseinstr) $(brokengasinst) > KBUILD_CFLAGS += $(call cc-option,-mabi=lp64) > KBUILD_AFLAGS += $(call cc-option,-mabi=lp64) > > +ifeq ($(CONFIG_ARM64_PTR_AUTH),y) > +KBUILD_CFLAGS += -msign-return-address=all > +endif Should not it be done via cc-option so old toolchains keep working [1]? [1] $ aarch64-linux-gnu-gcc --version aarch64-linux-gnu-gcc (Linaro GCC 2014.11) 4.9.3 20141031 (prerelease) Copyright (C) 2014 Free Software Foundation, Inc. This is free software; see the source for copying conditions. There is NO warranty; not even for MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. $ aarch64-linux-gnu-gcc -msign-return-address=all aarch64-linux-gnu-gcc: error: unrecognized command line option '-msign-return-address=all' ... Cheers Vladimir