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=-19.2 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,USER_AGENT_GIT 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 C0C57C433ED for ; Thu, 29 Apr 2021 23:26:45 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 8E6BA613D8 for ; Thu, 29 Apr 2021 23:26:45 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229637AbhD2X1X (ORCPT ); Thu, 29 Apr 2021 19:27:23 -0400 Received: from mail.kernel.org ([198.145.29.99]:50044 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229519AbhD2X1W (ORCPT ); Thu, 29 Apr 2021 19:27:22 -0400 Received: by mail.kernel.org (Postfix) with ESMTPSA id 051FA60FEF; Thu, 29 Apr 2021 23:26:32 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1619738795; bh=iJnXiao/XqJdR6XikaxL4phVBTlASI0UZ03/8UYRsLk=; h=From:To:Cc:Subject:Date:From; b=d44QNcLPGSM+kCDPp7yHT0u0uEyKxuNDm6h+5Q0BBaT6bPeNviE2dtANZpanzIC14 wAo1jZmN2LXikYcaYtbZMQj4Lc3qFQzjBKE60f7sGscInv7osU9CSVjhehY9iiRwC7 8RKhKyVlEPE9X47hXq/pJEUZ11tNwLga1z2kfUZMuysXWJ36dvj3FKYDzj8jpV0SZR kJWdFY3tk/k0GlEsqJ9g/tmgfHjPrFPh4mxeybyumwkfCm/PYQLPtpA+FocNBPmfNO s/IzHq542B4lUk5Rzyz0oWcaw3y/bvJEp/Zc517evQTDtqFPWX8I0FaHpPC6jZ1AtJ u5KsLa7SEwKfA== From: Nathan Chancellor To: Thomas Gleixner , Ingo Molnar , Borislav Petkov , x86@kernel.org, Sami Tolvanen , Kees Cook Cc: "H. Peter Anvin" , Nick Desaulniers , linux-kernel@vger.kernel.org, clang-built-linux@googlegroups.com, Nathan Chancellor Subject: [PATCH] x86: Enable clang LTO for 32-bit as well Date: Thu, 29 Apr 2021 16:26:12 -0700 Message-Id: <20210429232611.3966964-1-nathan@kernel.org> X-Mailer: git-send-email 2.31.1.362.g311531c9de MIME-Version: 1.0 X-Patchwork-Bot: notify Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Commit b33fff07e3e3 ("x86, build: allow LTO to be selected") enabled support for LTO for x86_64 but 32-bit works fine as well. I tested the following config combinations: * i386_defconfig + CONFIG_LTO_CLANG_FULL=y * i386_defconfig + CONFIG_LTO_CLANG_THIN=y * ARCH=i386 allmodconfig + CONFIG_LTO_CLANG_THIN=y with LLVM 11.1.0, 12.0.0, and 13.0.0 from git without any build failures. The defconfigs boot in QEMU with no new warnings. Signed-off-by: Nathan Chancellor --- arch/x86/Kconfig | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig index 0fc82237414d..d8a919d9535e 100644 --- a/arch/x86/Kconfig +++ b/arch/x86/Kconfig @@ -97,8 +97,8 @@ config X86 select ARCH_SUPPORTS_DEBUG_PAGEALLOC select ARCH_SUPPORTS_NUMA_BALANCING if X86_64 select ARCH_SUPPORTS_KMAP_LOCAL_FORCE_MAP if NR_CPUS <= 4096 - select ARCH_SUPPORTS_LTO_CLANG if X86_64 - select ARCH_SUPPORTS_LTO_CLANG_THIN if X86_64 + select ARCH_SUPPORTS_LTO_CLANG + select ARCH_SUPPORTS_LTO_CLANG_THIN select ARCH_USE_BUILTIN_BSWAP select ARCH_USE_QUEUED_RWLOCKS select ARCH_USE_QUEUED_SPINLOCKS base-commit: d8201efe75e13146ebde433745c7920e15593baf -- 2.31.1.362.g311531c9de