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=-22.4 required=3.0 tests=DKIMWL_WL_MED,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH, MAILING_LIST_MULTI,MENTIONS_GIT_HOSTING,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS, URIBL_BLOCKED,USER_AGENT_GIT,USER_IN_DEF_DKIM_WL 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 C20BAC3A5A1 for ; Wed, 28 Aug 2019 22:56:28 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 8A927233A1 for ; Wed, 28 Aug 2019 22:56:28 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=google.com header.i=@google.com header.b="CMVAnmm+" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727492AbfH1W41 (ORCPT ); Wed, 28 Aug 2019 18:56:27 -0400 Received: from mail-pl1-f202.google.com ([209.85.214.202]:53794 "EHLO mail-pl1-f202.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727432AbfH1W4Z (ORCPT ); Wed, 28 Aug 2019 18:56:25 -0400 Received: by mail-pl1-f202.google.com with SMTP id y22so801511plr.20 for ; Wed, 28 Aug 2019 15:56:24 -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=tRdkLp5blIPkAjhL3VcWLqU9CGzkwns+t7XttYIchcI=; b=CMVAnmm+YWw/BIadUY7YkC8sx7aCqztSp28UEVdIAoBP/Db56oZcYwzwqO2lnEiwxy HeMLtZhGYyQIkv8VzXp/1ZoAc0KOiEx25s63pADHK/NT70OynSBYThUHxroz2TMm1IpL 4OlZhZdHoED0+GrWWY9KfbkPon3aclDJJa4vn6vu4wuP7Q6YFcILIJ4JkxR6PJHmKuwW 66wIkcJmowDYRiYd4A8lM+pQRGPmeKsp2m9hUm07nv0DKitnTk2ic9IyXNfR4sdS9c0v UibkgV0Ij7jXR0sDh9icT4PqjlrjUFopN82MmtPfRSnV9hQ+95iec5iGoo3PJyKVAa1w mW3A== 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=tRdkLp5blIPkAjhL3VcWLqU9CGzkwns+t7XttYIchcI=; b=epLGLxsyDB+YkgSAw5UkwlWQpU13Rud74o19oRyE8Oyui5fXKF0ozaJcTLIHP94DXh S2OfccajetRpQ+swdagTniFESj75Zj1XjsdSeJSbsU4Tsmk8+vxz4xjfESIf3cNKMFod qJxU5KR5gzM3B4+807QT1Vva0lio9xrpaLcokRQL5EvtM/w2HMhDNqkUydWWz1Ehd0ef cql9nP/x8K2lONghM7HMinvnHx1ePjFcMM8iR3Zdw0QxLF4VMAN6gEZ0ixn6o5mg/akf TJKoqSoLS7ryubk6KSsMkwp4Oj00rYwmANM3nBcvFoJ4CzVsrlERR2f9fn04NmS2hon2 LySQ== X-Gm-Message-State: APjAAAWDGTc8U6AwTysGLtbOH5JGl5muebKmNl7xFAGQW6u0tX9L3RLr ShVn7eCkfEkvIvzKXKRAvTOGq9vZYWh5NfXMx3Q= X-Google-Smtp-Source: APXvYqxQtZsNffacR0VQzaCbJkVABImYb24Hctqo2E4YlQtYRyUCNEzArnOOaWsze5Dzo41VlZp0DGzyuIYCBkOBC5k= X-Received: by 2002:a65:638c:: with SMTP id h12mr5450926pgv.436.1567032983334; Wed, 28 Aug 2019 15:56:23 -0700 (PDT) Date: Wed, 28 Aug 2019 15:55:31 -0700 In-Reply-To: <20190828225535.49592-1-ndesaulniers@google.com> Message-Id: <20190828225535.49592-11-ndesaulniers@google.com> Mime-Version: 1.0 References: <20190828225535.49592-1-ndesaulniers@google.com> X-Mailer: git-send-email 2.23.0.187.g17f5b7556c-goog Subject: [PATCH v3 10/14] x86: prefer __section from compiler_attributes.h From: Nick Desaulniers To: miguel.ojeda.sandonis@gmail.com Cc: sedat.dilek@gmail.com, will@kernel.org, jpoimboe@redhat.com, naveen.n.rao@linux.vnet.ibm.com, davem@davemloft.net, paul.burton@mips.com, clang-built-linux@googlegroups.com, linux-kernel@vger.kernel.org, Nick Desaulniers Content-Type: text/plain; charset="UTF-8" Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org GCC unescapes escaped string section names while Clang does not. Because __section uses the `#` stringification operator for the section name, it doesn't need to be escaped. Instead, we should: 1. Prefer __section(.section_name_no_quotes). 2. Only use __attribute__((__section__(".section"))) when creating the section name via C preprocessor (see the definition of __define_initcall in arch/um/include/shared/init.h). This antipattern was found with: $ grep -e __section\(\" -e __section__\(\" -r See the discussions in: Link: https://bugs.llvm.org/show_bug.cgi?id=42950 Link: https://marc.info/?l=linux-netdev&m=156412960619946&w=2 Link: https://github.com/ClangBuiltLinux/linux/issues/619 Reported-by: Sedat Dilek Suggested-by: Josh Poimboeuf Tested-by: Sedat Dilek Signed-off-by: Nick Desaulniers --- arch/x86/include/asm/cache.h | 2 +- arch/x86/include/asm/intel-mid.h | 2 +- arch/x86/include/asm/iommu_table.h | 5 ++--- arch/x86/include/asm/irqflags.h | 2 +- arch/x86/include/asm/mem_encrypt.h | 2 +- arch/x86/kernel/cpu/cpu.h | 3 +-- 6 files changed, 7 insertions(+), 9 deletions(-) diff --git a/arch/x86/include/asm/cache.h b/arch/x86/include/asm/cache.h index abe08690a887..bb9f4bf4ec02 100644 --- a/arch/x86/include/asm/cache.h +++ b/arch/x86/include/asm/cache.h @@ -8,7 +8,7 @@ #define L1_CACHE_SHIFT (CONFIG_X86_L1_CACHE_SHIFT) #define L1_CACHE_BYTES (1 << L1_CACHE_SHIFT) -#define __read_mostly __attribute__((__section__(".data..read_mostly"))) +#define __read_mostly __section(.data..read_mostly) #define INTERNODE_CACHE_SHIFT CONFIG_X86_INTERNODE_CACHE_SHIFT #define INTERNODE_CACHE_BYTES (1 << INTERNODE_CACHE_SHIFT) diff --git a/arch/x86/include/asm/intel-mid.h b/arch/x86/include/asm/intel-mid.h index 8e5af119dc2d..f51f04aefe1b 100644 --- a/arch/x86/include/asm/intel-mid.h +++ b/arch/x86/include/asm/intel-mid.h @@ -43,7 +43,7 @@ struct devs_id { #define sfi_device(i) \ static const struct devs_id *const __intel_mid_sfi_##i##_dev __used \ - __attribute__((__section__(".x86_intel_mid_dev.init"))) = &i + __section(.x86_intel_mid_dev.init) = &i /** * struct mid_sd_board_info - template for SD device creation diff --git a/arch/x86/include/asm/iommu_table.h b/arch/x86/include/asm/iommu_table.h index 1fb3fd1a83c2..7d190710eb92 100644 --- a/arch/x86/include/asm/iommu_table.h +++ b/arch/x86/include/asm/iommu_table.h @@ -50,9 +50,8 @@ struct iommu_table_entry { #define __IOMMU_INIT(_detect, _depend, _early_init, _late_init, _finish)\ static const struct iommu_table_entry \ - __iommu_entry_##_detect __used \ - __attribute__ ((unused, __section__(".iommu_table"), \ - aligned((sizeof(void *))))) \ + __iommu_entry_##_detect __used __section(.iommu_table) \ + __aligned((sizeof(void *))) \ = {_detect, _depend, _early_init, _late_init, \ _finish ? IOMMU_FINISH_IF_DETECTED : 0} /* diff --git a/arch/x86/include/asm/irqflags.h b/arch/x86/include/asm/irqflags.h index 8a0e56e1dcc9..68db90bca813 100644 --- a/arch/x86/include/asm/irqflags.h +++ b/arch/x86/include/asm/irqflags.h @@ -9,7 +9,7 @@ #include /* Provide __cpuidle; we can't safely include */ -#define __cpuidle __attribute__((__section__(".cpuidle.text"))) +#define __cpuidle __section(.cpuidle.text) /* * Interrupt control: diff --git a/arch/x86/include/asm/mem_encrypt.h b/arch/x86/include/asm/mem_encrypt.h index 0c196c47d621..db2cd3709148 100644 --- a/arch/x86/include/asm/mem_encrypt.h +++ b/arch/x86/include/asm/mem_encrypt.h @@ -50,7 +50,7 @@ void __init mem_encrypt_free_decrypted_mem(void); bool sme_active(void); bool sev_active(void); -#define __bss_decrypted __attribute__((__section__(".bss..decrypted"))) +#define __bss_decrypted __section(.bss..decrypted) #else /* !CONFIG_AMD_MEM_ENCRYPT */ diff --git a/arch/x86/kernel/cpu/cpu.h b/arch/x86/kernel/cpu/cpu.h index c0e2407abdd6..7ff9dc41a603 100644 --- a/arch/x86/kernel/cpu/cpu.h +++ b/arch/x86/kernel/cpu/cpu.h @@ -38,8 +38,7 @@ struct _tlb_table { #define cpu_dev_register(cpu_devX) \ static const struct cpu_dev *const __cpu_dev_##cpu_devX __used \ - __attribute__((__section__(".x86_cpu_dev.init"))) = \ - &cpu_devX; + __section(.x86_cpu_dev.init) = &cpu_devX; extern const struct cpu_dev *const __x86_cpu_dev_start[], *const __x86_cpu_dev_end[]; -- 2.23.0.187.g17f5b7556c-goog