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=-7.1 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI, SIGNED_OFF_BY,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 3859AC43219 for ; Mon, 29 Apr 2019 20:28:23 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id F04B321655 for ; Mon, 29 Apr 2019 20:28:22 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=efficios.com header.i=@efficios.com header.b="joV9WmxE" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729342AbfD2U2V (ORCPT ); Mon, 29 Apr 2019 16:28:21 -0400 Received: from mail.efficios.com ([167.114.142.138]:51518 "EHLO mail.efficios.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1729212AbfD2U2V (ORCPT ); Mon, 29 Apr 2019 16:28:21 -0400 Received: from localhost (ip6-localhost [IPv6:::1]) by mail.efficios.com (Postfix) with ESMTP id 462E71DA3AD; Mon, 29 Apr 2019 16:28:19 -0400 (EDT) Received: from mail.efficios.com ([IPv6:::1]) by localhost (mail02.efficios.com [IPv6:::1]) (amavisd-new, port 10032) with ESMTP id lfsha8KaN3Fx; Mon, 29 Apr 2019 16:28:18 -0400 (EDT) Received: from localhost (ip6-localhost [IPv6:::1]) by mail.efficios.com (Postfix) with ESMTP id 465211DA3A4; Mon, 29 Apr 2019 16:28:18 -0400 (EDT) DKIM-Filter: OpenDKIM Filter v2.10.3 mail.efficios.com 465211DA3A4 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=efficios.com; s=default; t=1556569698; bh=YdzuJk5SnUFbR7C4FKv2y0/l5GDXHqEZ1IsDFtfLIUU=; h=Date:From:To:Message-ID:MIME-Version; b=joV9WmxEQVsqv19xO5E+SX74B/DmyGn6EayUx6zUFDMkG+aZpO/OwVshAQ75YdpCN 9H414rbzLgB39elHjRYUbZ6ZCymS+V11b9Vpngz2cvicrJ6iJ6wT8YjE/UwtlSruF4 Ri63rFjdn1PoO8MEhAsVjjPvaA6OGnRXJ6DlneymQ5olMeBwzNf/kdeqBR6reW79PQ 3f++EZ9boHhC6ok8or6vGjriDoH2E1hDb0kV2Lj8T+W6wAPjPjIdYzZKghgM4ShWjn ZIIJujpKMw7UA1qqREsVKKowtWi8VeKtdHf+M2/1fnF+cGZWZqErIixavrdoVs+Qn+ LKzDi6vPjokAA== X-Virus-Scanned: amavisd-new at efficios.com Received: from mail.efficios.com ([IPv6:::1]) by localhost (mail02.efficios.com [IPv6:::1]) (amavisd-new, port 10026) with ESMTP id C8GZDjvDNJLn; Mon, 29 Apr 2019 16:28:18 -0400 (EDT) Received: from mail02.efficios.com (mail02.efficios.com [167.114.142.138]) by mail.efficios.com (Postfix) with ESMTP id 261AB1DA393; Mon, 29 Apr 2019 16:28:18 -0400 (EDT) Date: Mon, 29 Apr 2019 16:28:18 -0400 (EDT) From: Mathieu Desnoyers To: ndesaulniers , shuah Cc: Masahiro Yamada , linux-kernel , linux-api , Thomas Gleixner , Peter Zijlstra , "Paul E . McKenney" , Boqun Feng , Andy Lutomirski , Dave Watson , Paul Turner , Andrew Morton , Russell King , Ingo Molnar , "H. Peter Anvin" , Andi Kleen , Chris Lameter , Ben Maurer , rostedt , Josh Triplett , Linus Torvalds , Catalin Marinas , Will Deacon , Michael Kerrisk , Joel Fernandes , linux-kselftest , clang-built-linux Message-ID: <712082435.384.1556569697998.JavaMail.zimbra@efficios.com> In-Reply-To: References: <20190429152803.7719-1-mathieu.desnoyers@efficios.com> <20190429152803.7719-13-mathieu.desnoyers@efficios.com> Subject: Re: [PATCH for 5.2 12/12] rseq/selftests: add -no-integrated-as for clang MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 7bit X-Originating-IP: [167.114.142.138] X-Mailer: Zimbra 8.8.12_GA_3794 (ZimbraWebClient - FF66 (Linux)/8.8.12_GA_3794) Thread-Topic: rseq/selftests: add -no-integrated-as for clang Thread-Index: Ac/EHQ/mSHgf8Nq7m+w8ff+ojTnKhQ== Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org ----- On Apr 29, 2019, at 1:03 PM, ndesaulniers ndesaulniers@google.com wrote: > On Mon, Apr 29, 2019 at 8:29 AM Mathieu Desnoyers > wrote: >> >> Ongoing work for asm goto support from clang requires the >> -no-integrated-as compiler flag. >> >> This compiler flag is present in the toplevel kernel Makefile, >> but is not replicated for selftests. Add it specifically for >> the rseq selftest which requires asm goto. >> >> Link: https://reviews.llvm.org/D56571 >> Signed-off-by: Mathieu Desnoyers >> CC: Nick Desaulniers >> CC: Thomas Gleixner >> CC: Joel Fernandes >> CC: Peter Zijlstra >> CC: Catalin Marinas >> CC: Dave Watson >> CC: Will Deacon >> CC: Shuah Khan >> CC: Andi Kleen >> CC: linux-kselftest@vger.kernel.org >> CC: "H . Peter Anvin" >> CC: Chris Lameter >> CC: Russell King >> CC: Michael Kerrisk >> CC: "Paul E . McKenney" >> CC: Paul Turner >> CC: Boqun Feng >> CC: Josh Triplett >> CC: Steven Rostedt >> CC: Ben Maurer >> CC: linux-api@vger.kernel.org >> CC: Andy Lutomirski >> CC: Andrew Morton >> CC: Linus Torvalds >> --- >> tools/testing/selftests/rseq/Makefile | 8 +++++++- >> 1 file changed, 7 insertions(+), 1 deletion(-) >> >> diff --git a/tools/testing/selftests/rseq/Makefile >> b/tools/testing/selftests/rseq/Makefile >> index c30c52e1d0d2..d6469535630a 100644 >> --- a/tools/testing/selftests/rseq/Makefile >> +++ b/tools/testing/selftests/rseq/Makefile >> @@ -1,5 +1,11 @@ >> # SPDX-License-Identifier: GPL-2.0+ OR MIT >> -CFLAGS += -O2 -Wall -g -I./ -I../../../../usr/include/ -L./ -Wl,-rpath=./ >> + >> +ifneq ($(shell $(CC) --version 2>&1 | head -n 1 | grep clang),) >> +CLANG_FLAGS += -no-integrated-as >> +endif >> + >> +CFLAGS += -O2 -Wall -g -I./ -I../../../../usr/include/ -L./ -Wl,-rpath=./ \ >> + $(CLANG_FLAGS) > > The top level Makefile exports $(CLANG_FLAGS), which should contain > `-no-integrated-as`. Is that available here? If so, then you can > just add `$(CLANG_FLAGS)`, no compiler check needed. AFAIU, the makefiles under tools/testing/selftests all end up including tools/testing/selftests/lib.mk, which states: "# This mimics the top-level Makefile. We do it explicitly here so that this # Makefile can operate with or without the kbuild infrastructure." So I don't think it's using any of the definitions from the toplevel Makefile. > If not, maybe the test for CONFIG_CC_IS_CLANG is cleaner? A quick test indicates that the toplevel CONFIG_* definitions are unavailable from the kernel selftests makefiles. > Thanks for the patch, and helping test asm goto in Clang! You're very welcome! Considering that I intend to have rseq widely adopted in user-space, it's only natural to consider that its user-space side needs to be compiled by clang as well. Thanks, Mathieu -- Mathieu Desnoyers EfficiOS Inc. http://www.efficios.com