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=-7.2 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,MENTIONS_GIT_HOSTING,SPF_HELO_NONE,SPF_PASS, USER_AGENT_SANE_1 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 14A92C433E0 for ; Wed, 27 May 2020 13:53:29 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id D32032078C for ; Wed, 27 May 2020 13:53:28 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2388944AbgE0Nx1 (ORCPT ); Wed, 27 May 2020 09:53:27 -0400 Received: from foss.arm.com ([217.140.110.172]:38910 "EHLO foss.arm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2388713AbgE0Nx1 (ORCPT ); Wed, 27 May 2020 09:53:27 -0400 Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.121.207.14]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id C9B6630E; Wed, 27 May 2020 06:53:26 -0700 (PDT) Received: from arm.com (usa-sjc-imap-foss1.foss.arm.com [10.121.207.14]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id 17D9C3F6C4; Wed, 27 May 2020 06:53:24 -0700 (PDT) Date: Wed, 27 May 2020 14:53:22 +0100 From: Dave Martin To: Will Deacon Cc: Nick Desaulniers , Catalin Marinas , Naohiro Aota , Stephen Boyd , Masahiro Yamada , linux-kernel@vger.kernel.org, Manoj Gupta , Luis Lozano , Nathan Chancellor , Vincenzo Frascino , linux-arm-kernel@lists.infradead.org Subject: Re: [PATCH] arm64: vdso32: force vdso32 to be compiled as -marm Message-ID: <20200527135322.GU5031@arm.com> References: <20200526173117.155339-1-ndesaulniers@google.com> <159052247565.23781.7800427985507723263.b4-ty@kernel.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <159052247565.23781.7800427985507723263.b4-ty@kernel.org> User-Agent: Mutt/1.5.23 (2014-03-12) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Tue, May 26, 2020 at 09:45:05PM +0100, Will Deacon wrote: > On Tue, 26 May 2020 10:31:14 -0700, Nick Desaulniers wrote: > > Custom toolchains that modify the default target to -mthumb cannot It's probably too late to water this down, but it's unfortunate to have this comment in the upstream commit history. It's not constructive to call the native compiler configuration of major distros for many years a "custom" toolchain. Unmodified GCC has had a clean configure option for this for a very long time; it's not someone's dirty hack. (The wisdom of armhf's choice of -mthumb might be debated, but it is well established.) Ignoring the triplet and passing random options to a compiler in the hopes that it will do the right thing for an irregular usecase has never been reliable. Usecases don't get much more irregular than building vdso32. arch/arm has the proper options in its Makefiles. This patch is a kernel bugfix, plain and simple. > > compile the arm64 compat vdso32, as > > arch/arm64/include/asm/vdso/compat_gettimeofday.h > > contains assembly that's invalid in -mthumb. Force the use of -marm, > > always. > > Applied to arm64 (for-next/vdso), thanks! > > [1/1] arm64: vdso32: force vdso32 to be compiled as -marm > https://git.kernel.org/arm64/c/20363b59ad4f Does this need to go to stable? Cheers ---Dave