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=-20.4 required=3.0 tests=BAYES_00,DKIMWL_WL_MED, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS, URIBL_BLOCKED,USER_AGENT_GIT,USER_IN_DEF_DKIM_WL autolearn=unavailable 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 EEA89C43463 for ; Fri, 18 Sep 2020 20:16:51 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id A0A6723119 for ; Fri, 18 Sep 2020 20:16:51 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=google.com header.i=@google.com header.b="BCRPev+r" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726360AbgIRUQq (ORCPT ); Fri, 18 Sep 2020 16:16:46 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:53062 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726732AbgIRUP6 (ORCPT ); Fri, 18 Sep 2020 16:15:58 -0400 Received: from mail-yb1-xb4a.google.com (mail-yb1-xb4a.google.com [IPv6:2607:f8b0:4864:20::b4a]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id BDF63C0613DD for ; Fri, 18 Sep 2020 13:15:52 -0700 (PDT) Received: by mail-yb1-xb4a.google.com with SMTP id p187so6738458ybg.14 for ; Fri, 18 Sep 2020 13:15:52 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20161025; h=sender:date:in-reply-to:message-id:mime-version:references:subject :from:to:cc; bh=o2DL67IOGBCnkKLJVmvx6mUhLGuExASqR4QZ4OZyxOY=; b=BCRPev+rE/eCdhTRad14OxKPRC759YffFhBrw/j99zRl+XMk2SeRH2Ro57Q+fpYAoY 41dQCr5nRdN1nuAqPl79eRYF7Et/K4hrYua59TnFUm5Qft7hifOftA32AELoX+E867b9 2jVvQFpvTUQ2M35PWVTe002iSNw0bKhWwMU3J5xh89MftQHJTF8aTjqfy5S8odXPfmkR B2V75MstoeJ9GqBepGfubW5/qhE+jhI/WYG/r7dM4O293zVEla547bOEPQpSKmz7YdJU wGZC1Jet9cEIKlifpza3a2tLHND8kbzGrtrT3REGXctWnfeV7IsjeRGJP72+hJcsyY8w zCoQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:sender:date:in-reply-to:message-id:mime-version :references:subject:from:to:cc; bh=o2DL67IOGBCnkKLJVmvx6mUhLGuExASqR4QZ4OZyxOY=; b=m+Hhc1jp3jb3/eC74FUXVZzJqS/FUhI0HvqvMO5Q074FWTytd3i5ejo8tpAKTA22F8 6ko/WqfO9n19kS6cVyXjr33940kfjYIsOPfJa5YQbUoRMqwS3KjWx3fAH5rz8tE4SUBR lxfdY6pWacjP4TLH6hVlU7wtot2n67m6LNjArdB+XoPKrQn5DZGeCEdH1MCGwZzx33bR G+YuZuuVc613uwm+zI4hTqqmQ3Wz/O7JVP1YPeXw33ojLKk+EyiFxU+neGvTcHLmVwKI dba7n9K9924idUbRnoAa1ksYHsyyzdBd3Gka6kG0f2wXbgzhC0dSO7vIccnOYasD10kH TG2A== X-Gm-Message-State: AOAM531GcKKQMVeGZtDq42N9Wo6TGuwY2sXFEb3PAaRhfCpoSCViNjfT Zelb8bhZWcT2zCjyEEJlh9N+tmRak5Br30uH7DQ= X-Google-Smtp-Source: ABdhPJwrzpZNvpYit1QmzfPWE8TC9Luw0JQEd0AJRVJCA8aClr3KtmTNrVIGHe8CNeT/kpakU/IVCxd5qz42yc0kkDA= Sender: "samitolvanen via sendgmr" X-Received: from samitolvanen1.mtv.corp.google.com ([2620:15c:201:2:f693:9fff:fef4:1b6d]) (user=samitolvanen job=sendgmr) by 2002:a25:887:: with SMTP id 129mr35650576ybi.513.1600460151944; Fri, 18 Sep 2020 13:15:51 -0700 (PDT) Date: Fri, 18 Sep 2020 13:14:36 -0700 In-Reply-To: <20200918201436.2932360-1-samitolvanen@google.com> Message-Id: <20200918201436.2932360-31-samitolvanen@google.com> Mime-Version: 1.0 References: <20200918201436.2932360-1-samitolvanen@google.com> X-Mailer: git-send-email 2.28.0.681.g6f77f65b4e-goog Subject: [PATCH v3 30/30] x86, build: allow LTO_CLANG and THINLTO to be selected From: Sami Tolvanen To: Masahiro Yamada , Will Deacon Cc: Peter Zijlstra , Steven Rostedt , Greg Kroah-Hartman , "Paul E. McKenney" , Kees Cook , Nick Desaulniers , clang-built-linux@googlegroups.com, kernel-hardening@lists.openwall.com, linux-arch@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-kbuild@vger.kernel.org, linux-kernel@vger.kernel.org, linux-pci@vger.kernel.org, x86@kernel.org, Sami Tolvanen Content-Type: text/plain; charset="UTF-8" Precedence: bulk List-ID: X-Mailing-List: linux-arch@vger.kernel.org Pass code model and stack alignment to the linker as these are not stored in LLVM bitcode, and allow both CONFIG_LTO_CLANG and CONFIG_THINLTO to be selected. Signed-off-by: Sami Tolvanen Reviewed-by: Kees Cook --- arch/x86/Kconfig | 2 ++ arch/x86/Makefile | 5 +++++ 2 files changed, 7 insertions(+) diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig index 6de2e5c0bdba..0a49008c2363 100644 --- a/arch/x86/Kconfig +++ b/arch/x86/Kconfig @@ -92,6 +92,8 @@ config X86 select ARCH_SUPPORTS_ACPI select ARCH_SUPPORTS_ATOMIC_RMW select ARCH_SUPPORTS_NUMA_BALANCING if X86_64 + select ARCH_SUPPORTS_LTO_CLANG if X86_64 + select ARCH_SUPPORTS_THINLTO if X86_64 select ARCH_USE_BUILTIN_BSWAP select ARCH_USE_QUEUED_RWLOCKS select ARCH_USE_QUEUED_SPINLOCKS diff --git a/arch/x86/Makefile b/arch/x86/Makefile index 4346ffb2e39f..49e3b8674eb5 100644 --- a/arch/x86/Makefile +++ b/arch/x86/Makefile @@ -173,6 +173,11 @@ ifeq ($(ACCUMULATE_OUTGOING_ARGS), 1) KBUILD_CFLAGS += $(call cc-option,-maccumulate-outgoing-args,) endif +ifdef CONFIG_LTO_CLANG +KBUILD_LDFLAGS += -plugin-opt=-code-model=kernel \ + -plugin-opt=-stack-alignment=$(if $(CONFIG_X86_32),4,8) +endif + # Workaround for a gcc prelease that unfortunately was shipped in a suse release KBUILD_CFLAGS += -Wno-sign-compare # -- 2.28.0.681.g6f77f65b4e-goog