From patchwork Wed Jun 24 20:32:00 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Sami Tolvanen X-Patchwork-Id: 11624201 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 9A59F60D for ; Wed, 24 Jun 2020 20:33:43 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 8096320857 for ; Wed, 24 Jun 2020 20:33:43 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=google.com header.i=@google.com header.b="qDi1kJQp" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2406594AbgFXUdn (ORCPT ); Wed, 24 Jun 2020 16:33:43 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:50692 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2406612AbgFXUdj (ORCPT ); Wed, 24 Jun 2020 16:33:39 -0400 Received: from mail-qv1-xf4a.google.com (mail-qv1-xf4a.google.com [IPv6:2607:f8b0:4864:20::f4a]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id CB518C06179A for ; Wed, 24 Jun 2020 13:33:38 -0700 (PDT) Received: by mail-qv1-xf4a.google.com with SMTP id v20so2489123qvt.15 for ; Wed, 24 Jun 2020 13:33:38 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20161025; h=date:in-reply-to:message-id:mime-version:references:subject:from:to :cc; bh=tvg1Fbryi0kMABLSJZV+2LlG9cMfXZohRvKr2b10/ew=; b=qDi1kJQp6Ay8PowzBhvgcAgfJKyEY22DJ3SehuRqjn/jA9tuCP3XgBFwyavVII/8H8 +qDUOb2y6OKXwsbI5cxksI3QZk1MHXAA03OHDhdjTbrRcF9EMaP1PLIUJPhY0/usboE5 WysdzKDHLGBWRBK078rHZqlAErXt2qVt2sq358db2q+vTaEhfb2Ztz8s+Npc56SUR/GU zam+aC0Fi9TXcLLkm/vCwtmB9CZFKkHlUgIzUuWu5eMrmtKdAXKTOQSgFxHw8mPgwD7i VrVAm6xkIce/iluM0BjvQMvc/W7Io0XF/CLOQ/Xz7mhbTAKzZSonAVtghl5cbcwT3k0W qRXw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:date:in-reply-to:message-id:mime-version :references:subject:from:to:cc; bh=tvg1Fbryi0kMABLSJZV+2LlG9cMfXZohRvKr2b10/ew=; b=B0YjEefiOipd4Try1pQlh9XfHbuXZLki6BdYn6CiEWF6CxEfMkZtn+RxKE4unDluZu xxY1v1JJwug+GPeQa4uch7tGD7uAXPHAtZ6JdLBqxcv5X8IGdAiBWjb7qR42Srd9QZjn BtuY6ZYb9265NlWr/ZyPxUSkcA6FwXt8qCyvL8YIZVSO/GB1SPe00xRFl/rqwCQ91ztc yeYQDeVTnoOEZSKqlJMjj7IKkiiS/pILD/j3NjvSb81Oql9oK68QPrc0eQXF4RDxKpXO 6soZwsHcauQJ2Y0Qmhl9ggHmZoE8/6tfK5nn3JUKmvou8BlRbOfDhPHvuVL7rE6MQWPN 3TTQ== X-Gm-Message-State: AOAM530B3BI802m0/gJ1yJa43EDRiafLq8eDD0FP6OOmShbYmvq07ybl I4QXdTsRD1CONA18OVjcffAY2tXx5TZti/bZM18= X-Google-Smtp-Source: ABdhPJyl5JOyQAzphL8fSerF19PzJDrN7smlmqxmskm8wB3636prwAzfuisg2Ek7D9XrgzzDEO8QBVxE0nwET9TpJnI= X-Received: by 2002:a05:6214:846:: with SMTP id dg6mr31350632qvb.210.1593030818021; 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> X-Mailer: git-send-email 2.27.0.212.ge8ba1cc988-goog Subject: [PATCH 22/22] x86, build: allow LTO_CLANG and THINLTO to be selected From: Sami Tolvanen 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 Sender: linux-kbuild-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kbuild@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 #