From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from lindbergh.monkeyblade.net ([23.128.96.19]:56216 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725272AbgGAGB6 (ORCPT ); Wed, 1 Jul 2020 02:01:58 -0400 Received: from mail-wr1-x442.google.com (mail-wr1-x442.google.com [IPv6:2a00:1450:4864:20::442]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id F2A2CC061755 for ; Tue, 30 Jun 2020 23:01:57 -0700 (PDT) Received: by mail-wr1-x442.google.com with SMTP id r12so22430862wrj.13 for ; Tue, 30 Jun 2020 23:01:57 -0700 (PDT) Date: Wed, 1 Jul 2020 08:01:50 +0200 From: Marco Elver Subject: Re: [PATCH 1/2] kbuild: remove cc-option test of -fno-stack-protector Message-ID: <20200701060150.GA1181113@elver.google.com> References: <20200626185913.92890-1-masahiroy@kernel.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20200626185913.92890-1-masahiroy@kernel.org> Sender: linux-kbuild-owner@vger.kernel.org List-ID: To: Masahiro Yamada Cc: linux-kbuild@vger.kernel.org, clang-built-linux@googlegroups.com, x86@kernel.org, linux-efi@vger.kernel.org, Kees Cook , linux-kernel@vger.kernel.org, paulmck@kernel.org On Sat, Jun 27, 2020 at 03:59AM +0900, Masahiro Yamada wrote: > Some Makefiles already pass -fno-stack-protector unconditionally. > For example, arch/arm64/kernel/vdso/Makefile, arch/x86/xen/Makefile. > No problem report so far about hard-coding this option. So, we can > assume all supported compilers know -fno-stack-protector. > > GCC 4.8 and Clang support this option (https://godbolt.org/z/_HDGzN) > > Get rid of cc-option from -fno-stack-protector. > > Remove CONFIG_CC_HAS_STACKPROTECTOR_NONE, which should always be 'y'. > > Note: > arch/mips/vdso/Makefile adds -fno-stack-protector twice, first > unconditionally, and second conditionally. I removed the second one. > > Signed-off-by: Masahiro Yamada > --- > > Documentation/kbuild/kconfig-language.rst | 4 ++-- > Makefile | 2 +- > arch/Kconfig | 3 --- > arch/arm/boot/compressed/Makefile | 3 +-- > arch/mips/vdso/Makefile | 3 +-- > arch/powerpc/kernel/Makefile | 2 +- > arch/powerpc/platforms/powermac/Makefile | 2 +- > arch/sparc/vdso/Makefile | 4 ++-- > arch/um/Makefile | 3 +-- > arch/x86/Makefile | 2 +- > arch/x86/boot/compressed/Makefile | 2 +- > arch/x86/entry/vdso/Makefile | 4 ++-- > arch/x86/kernel/cpu/Makefile | 3 +-- > arch/x86/lib/Makefile | 2 +- > arch/x86/mm/Makefile | 7 +++---- > arch/x86/power/Makefile | 3 +-- > arch/x86/purgatory/Makefile | 2 +- > arch/x86/um/vdso/Makefile | 2 +- > arch/x86/xen/Makefile | 5 ++--- > drivers/firmware/efi/libstub/Makefile | 2 +- > drivers/xen/Makefile | 3 +-- > kernel/kcsan/Makefile | 3 +-- Is it possible that this patch drops the KCSAN portion? We have a patch that is part of a series intended for 5.9 that also removes the cc-option from -fno-stack-protector, but can't easily be dropped from the surrounding series. Please see: https://lkml.kernel.org/r/20200624190236.GA6603@paulmck-ThinkPad-P72 Thanks, -- Marco