From patchwork Thu Sep 19 22:04:00 2019 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Greg KH X-Patchwork-Id: 11153471 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id EEC7876 for ; Thu, 19 Sep 2019 22:22:13 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id CCA9D21D79 for ; Thu, 19 Sep 2019 22:22:13 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1568931733; bh=ATTSTQNzeM8sUDrhqGjI62uCRviZbT7bue9ppOoviPs=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=Rurz6cmKdAFg1svI6txFmzddqifjD3LDzL5a66KLVYsxmFvu7AFaNkD5M7J7ohBje 8+cQDzax9BAII7MH7QiJJRkzE4HLuZSzqX7AtwF1xdWbvA1ryOMZd6MzG3/xNJebkS OSc6O+wepMWA34FoXHOFVc+4YeofLiDChA9VYHdc= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2404758AbfISWWM (ORCPT ); Thu, 19 Sep 2019 18:22:12 -0400 Received: from mail.kernel.org ([198.145.29.99]:37052 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2406778AbfISWWK (ORCPT ); Thu, 19 Sep 2019 18:22:10 -0400 Received: from localhost (83-86-89-107.cable.dynamic.v4.ziggo.nl [83.86.89.107]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 5877C21927; Thu, 19 Sep 2019 22:22:09 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1568931729; bh=ATTSTQNzeM8sUDrhqGjI62uCRviZbT7bue9ppOoviPs=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=SIBwdd53HHOsyzU7I8eubSnyXON7rFH2W5gqUdA26alQi5fMwvZzuVexUcS6xuo58 mG/a6zLGwjZI2CR+YHKXpejRObyl0LxukyaB9IC9OHi+92VZzp5vl7SdHGzg7H0ytx tEFDsh94z3OmGxAlVraBY8/ENVSIY3Q3hCTomD90= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Paul Burton , Kevin Hilman , Guenter Roeck , "Maciej W. Rozycki" , linux-mips@vger.kernel.org Subject: [PATCH 4.4 19/56] MIPS: VDSO: Use same -m%-float cflag as the kernel proper Date: Fri, 20 Sep 2019 00:04:00 +0200 Message-Id: <20190919214753.768218356@linuxfoundation.org> X-Mailer: git-send-email 2.23.0 In-Reply-To: <20190919214742.483643642@linuxfoundation.org> References: <20190919214742.483643642@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Sender: linux-mips-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-mips@vger.kernel.org From: Paul Burton commit 0648e50e548d881d025b9419a1a168753c8e2bf7 upstream. The MIPS VDSO build currently doesn't provide the -msoft-float flag to the compiler as the kernel proper does. This results in an attempt to use the compiler's default floating point configuration, which can be problematic in cases where this is incompatible with the target CPU's -march= flag. For example decstation_defconfig fails to build using toolchains in which gcc was configured --with-fp-32=xx with the following error: LDS arch/mips/vdso/vdso.lds cc1: error: '-march=r3000' requires '-mfp32' make[2]: *** [scripts/Makefile.build:379: arch/mips/vdso/vdso.lds] Error 1 The kernel proper avoids this error because we build with the -msoft-float compiler flag, rather than using the compiler's default. Pass this flag through to the VDSO build so that it too becomes agnostic to the toolchain's floating point configuration. Note that this is filtered out from KBUILD_CFLAGS rather than simply always using -msoft-float such that if we switch the kernel to use -mno-float in the future the VDSO will automatically inherit the change. The VDSO doesn't actually include any floating point code, and its .MIPS.abiflags section is already manually generated to specify that it's compatible with any floating point ABI. As such this change should have no effect on the resulting VDSO, apart from fixing the build failure for affected toolchains. Signed-off-by: Paul Burton Reported-by: Kevin Hilman Reported-by: Guenter Roeck Tested-by: Kevin Hilman Fixes: ebb5e78cc634 ("MIPS: Initial implementation of a VDSO") Cc: Maciej W. Rozycki Cc: linux-mips@vger.kernel.org Cc: stable@vger.kernel.org # v4.4+ Cc: Guenter Roeck Signed-off-by: Greg Kroah-Hartman --- arch/mips/vdso/Makefile | 1 + 1 file changed, 1 insertion(+) --- a/arch/mips/vdso/Makefile +++ b/arch/mips/vdso/Makefile @@ -7,6 +7,7 @@ ccflags-vdso := \ $(filter -E%,$(KBUILD_CFLAGS)) \ $(filter -mmicromips,$(KBUILD_CFLAGS)) \ $(filter -march=%,$(KBUILD_CFLAGS)) \ + $(filter -m%-float,$(KBUILD_CFLAGS)) \ -D__VDSO__ cflags-vdso := $(ccflags-vdso) \ $(filter -W%,$(filter-out -Wa$(comma)%,$(KBUILD_CFLAGS))) \