From mboxrd@z Thu Jan 1 00:00:00 1970 From: Sami Tolvanen Subject: [PATCH 22/22] x86, build: allow LTO_CLANG and THINLTO to be selected Date: Wed, 24 Jun 2020 13:32:00 -0700 Message-ID: <20200624203200.78870-23-samitolvanen@google.com> References: <20200624203200.78870-1-samitolvanen@google.com> Mime-Version: 1.0 Content-Type: text/plain; charset="UTF-8" Return-path: In-Reply-To: <20200624203200.78870-1-samitolvanen@google.com> Sender: linux-kbuild-owner@vger.kernel.org To: Masahiro Yamada , Will Deacon Cc: 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 List-Id: linux-arch.vger.kernel.org Allow CONFIG_LTO_CLANG and CONFIG_THINLTO to be enabled. Signed-off-by: Sami Tolvanen --- arch/x86/Kconfig | 2 ++ arch/x86/Makefile | 5 +++++ 2 files changed, 7 insertions(+) diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig index 6a0cc524882d..df335b1f9c31 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 00e378de8bc0..a1abc1e081ad 100644 --- a/arch/x86/Makefile +++ b/arch/x86/Makefile @@ -188,6 +188,11 @@ ifdef CONFIG_X86_64 KBUILD_LDFLAGS += $(call ld-option, -z max-page-size=0x200000) endif +ifdef CONFIG_LTO_CLANG +KBUILD_LDFLAGS += -plugin-opt=-code-model=kernel \ + -plugin-opt=-stack-alignment=$(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 # -- 2.27.0.212.ge8ba1cc988-goog From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from lindbergh.monkeyblade.net ([23.128.96.19]:50672 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2406618AbgFXUdk (ORCPT ); Wed, 24 Jun 2020 16:33:40 -0400 Received: from mail-qt1-x849.google.com (mail-qt1-x849.google.com [IPv6:2607:f8b0:4864:20::849]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id C2BE4C061796 for ; Wed, 24 Jun 2020 13:33:38 -0700 (PDT) Received: by mail-qt1-x849.google.com with SMTP id y5so2427045qto.10 for ; Wed, 24 Jun 2020 13:33:38 -0700 (PDT) Date: Wed, 24 Jun 2020 13:32:00 -0700 In-Reply-To: <20200624203200.78870-1-samitolvanen@google.com> Message-ID: <20200624203200.78870-23-samitolvanen@google.com> Mime-Version: 1.0 References: <20200624203200.78870-1-samitolvanen@google.com> Subject: [PATCH 22/22] x86, build: allow LTO_CLANG and THINLTO to be selected From: Sami Tolvanen Content-Type: text/plain; charset="UTF-8" Sender: linux-arch-owner@vger.kernel.org List-ID: To: Masahiro Yamada , Will Deacon Cc: 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 Message-ID: <20200624203200.lVLTMSj8q5yQSwXN7hnM-dkMrSAD5k0KfbE9LjQgqBA@z> Allow CONFIG_LTO_CLANG and CONFIG_THINLTO to be enabled. Signed-off-by: Sami Tolvanen --- arch/x86/Kconfig | 2 ++ arch/x86/Makefile | 5 +++++ 2 files changed, 7 insertions(+) diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig index 6a0cc524882d..df335b1f9c31 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 00e378de8bc0..a1abc1e081ad 100644 --- a/arch/x86/Makefile +++ b/arch/x86/Makefile @@ -188,6 +188,11 @@ ifdef CONFIG_X86_64 KBUILD_LDFLAGS += $(call ld-option, -z max-page-size=0x200000) endif +ifdef CONFIG_LTO_CLANG +KBUILD_LDFLAGS += -plugin-opt=-code-model=kernel \ + -plugin-opt=-stack-alignment=$(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 # -- 2.27.0.212.ge8ba1cc988-goog