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 Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id C8DECC6FD1C for ; Fri, 24 Mar 2023 05:32:24 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231394AbjCXFcW (ORCPT ); Fri, 24 Mar 2023 01:32:22 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:50434 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230040AbjCXFcP (ORCPT ); Fri, 24 Mar 2023 01:32:15 -0400 Received: from 1wt.eu (wtarreau.pck.nerim.net [62.212.114.60]) by lindbergh.monkeyblade.net (Postfix) with ESMTP id 368E11980; Thu, 23 Mar 2023 22:32:10 -0700 (PDT) Received: (from willy@localhost) by mail.home.local (8.17.1/8.17.1/Submit) id 32O5W5q8025977; Fri, 24 Mar 2023 06:32:05 +0100 Date: Fri, 24 Mar 2023 06:32:05 +0100 From: Willy Tarreau To: Thomas =?iso-8859-1?Q?Wei=DFschuh?= Cc: Shuah Khan , linux-kernel@vger.kernel.org, linux-kselftest@vger.kernel.org Subject: Re: [PATCH v2 8/8] tools/nolibc: x86_64: add stackprotector support Message-ID: References: <20230223-nolibc-stackprotector-v2-0-4c938e098d67@weissschuh.net> <20230223-nolibc-stackprotector-v2-8-4c938e098d67@weissschuh.net> MIME-Version: 1.0 Content-Type: text/plain; charset=iso-8859-1 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Thu, Mar 23, 2023 at 11:44:15PM +0000, Thomas Weißschuh wrote: > Hi Willy, > > On Thu, Mar 23, 2023 at 09:19:48PM +0100, Willy Tarreau wrote: > > On Mon, Mar 20, 2023 at 03:41:08PM +0000, Thomas Weißschuh wrote: > > > Enable the new stackprotector support for x86_64. > > (...) > > > diff --git a/tools/testing/selftests/nolibc/Makefile b/tools/testing/selftests/nolibc/Makefile > > > index 8f069ebdd124..543555f4cbdc 100644 > > > --- a/tools/testing/selftests/nolibc/Makefile > > > +++ b/tools/testing/selftests/nolibc/Makefile > > > @@ -80,6 +80,8 @@ CFLAGS_STACKPROTECTOR = -DNOLIBC_STACKPROTECTOR \ > > > $(call cc-option,-mstack-protector-guard=global) \ > > > $(call cc-option,-fstack-protector-all) > > > CFLAGS_i386 = $(CFLAGS_STACKPROTECTOR) > > > +CFLAGS_x86_64 = $(CFLAGS_STACKPROTECTOR) > > > +CFLAGS_x86 = $(CFLAGS_STACKPROTECTOR) > > > CFLAGS_s390 = -m64 > > > CFLAGS ?= -Os -fno-ident -fno-asynchronous-unwind-tables \ > > > $(call cc-option,-fno-stack-protector) \ > > > > This change is making it almost impossible for me to pass external CFLAGS > > without forcefully disabling the automatic detection of stackprot. I need > > to do it for some archs (e.g. "-march=armv5t -mthumb") or even to change > > optimization levels. > > > > I figured that the simplest way to recover that functionality for me > > consists in using a dedicated variable to assign stack protector per > > supported architecure and concatenating it to the per-arch CFLAGS like > > this: > > > > diff --git a/tools/testing/selftests/nolibc/Makefile b/tools/testing/selftests/nolibc/Makefile > > index 543555f4cbdc..bbce57420465 100644 > > --- a/tools/testing/selftests/nolibc/Makefile > > +++ b/tools/testing/selftests/nolibc/Makefile > > @@ -79,13 +79,13 @@ endif > > CFLAGS_STACKPROTECTOR = -DNOLIBC_STACKPROTECTOR \ > > $(call cc-option,-mstack-protector-guard=global) \ > > $(call cc-option,-fstack-protector-all) > > -CFLAGS_i386 = $(CFLAGS_STACKPROTECTOR) > > -CFLAGS_x86_64 = $(CFLAGS_STACKPROTECTOR) > > -CFLAGS_x86 = $(CFLAGS_STACKPROTECTOR) > > +CFLAGS_STKP_i386 = $(CFLAGS_STACKPROTECTOR) > > +CFLAGS_STKP_x86_64 = $(CFLAGS_STACKPROTECTOR) > > +CFLAGS_STKP_x86 = $(CFLAGS_STACKPROTECTOR) > > CFLAGS_s390 = -m64 > > CFLAGS ?= -Os -fno-ident -fno-asynchronous-unwind-tables \ > > $(call cc-option,-fno-stack-protector) \ > > - $(CFLAGS_$(ARCH)) > > + $(CFLAGS_STKP_$(ARCH)) $(CFLAGS_$(ARCH)) > > LDFLAGS := -s > > > > help: > > > > And now with this it works again for me on all archs, with all of them > > showing "SKIPPED" for the -fstackprotector line except i386/x86_64 which > > show "OK". > > > > Are you OK with this approach ? And if so, do you want to respin it or > > do you want me to retrofit it into your 3 patches that introduce this > > change (it's easy enough so I really don't care) ? > > Looks good to me. > > If nothing else needs to be changed feel free to fix it up on your side. Perfect, will do it then. Thanks! Willy