diff options
Diffstat (limited to 'Clean-the-new-GCC-9--Wmissing-attributes-warnings.patch')
| -rw-r--r-- | Clean-the-new-GCC-9--Wmissing-attributes-warnings.patch | 450 |
1 files changed, 450 insertions, 0 deletions
diff --git a/Clean-the-new-GCC-9--Wmissing-attributes-warnings.patch b/Clean-the-new-GCC-9--Wmissing-attributes-warnings.patch new file mode 100644 index 000000000..bae06f892 --- /dev/null +++ b/Clean-the-new-GCC-9--Wmissing-attributes-warnings.patch @@ -0,0 +1,450 @@ +From patchwork Sat Feb 9 00:08:38 2019 +Content-Type: text/plain; charset="utf-8" +MIME-Version: 1.0 +Content-Transfer-Encoding: 7bit +X-Patchwork-Submitter: Miguel Ojeda <miguel.ojeda.sandonis@gmail.com> +X-Patchwork-Id: 1040186 +Return-Path: <SRS0=1U6d=QQ=vger.kernel.org=linux-kernel-owner@kernel.org> +Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) + by smtp.lore.kernel.org (Postfix) with ESMTP id CF5ACC169C4 + for <linux-kernel@archiver.kernel.org>; Sat, 9 Feb 2019 00:09:48 +0000 (UTC) +Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) + by mail.kernel.org (Postfix) with ESMTP id 9B6A22177B + for <linux-kernel@archiver.kernel.org>; Sat, 9 Feb 2019 00:09:48 +0000 (UTC) +Authentication-Results: mail.kernel.org; + dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com + header.b="fBDNHARm" +Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand + id S1726847AbfBIAJH (ORCPT + <rfc822;linux-kernel@archiver.kernel.org>); + Fri, 8 Feb 2019 19:09:07 -0500 +Received: from mail-wm1-f66.google.com ([209.85.128.66]:35134 "EHLO + mail-wm1-f66.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org + with ESMTP id S1726222AbfBIAJH (ORCPT + <rfc822;linux-kernel@vger.kernel.org>); + Fri, 8 Feb 2019 19:09:07 -0500 +Received: by mail-wm1-f66.google.com with SMTP id t200so6175302wmt.0 + for <linux-kernel@vger.kernel.org>; + Fri, 08 Feb 2019 16:09:05 -0800 (PST) +DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; + d=gmail.com; s=20161025; + h=from:to:cc:subject:date:message-id:in-reply-to:references; + bh=oYZRhi80jnWf5lvJ9rxSq8k+5uIG9VwWaCu5KNmb2Io=; + b=fBDNHARmMKhmm+ePaNJj9txjNbOdazSkbZWB/n5YjOQJiidCJgtPUkWYcWKtUsrySa + trWv7EzzGxFKTM9ccHPDsc7WS8wtoOlUSU00LZPieepciKS24buQhuHPZFvVIRn+531E + WXI4lpQh/8WxwUBQRjxoDJhdHoBt66E/f63atN5vJMnc3ThZSTsQ4Sfu52xF44sOuN/B + TE10KX4vZtqb0SGWn2TObNYiAWh6hRVzo8h9o1Ako8t4KyfHIuMFlVsnHfG/afjhbNIN + haKI0M5yLUxjlEGqljgCH6x51eoDN5o5GVzckrZ1zUZDuRe5854+1nj6iZ4SKOFLM5/t + hg6g== +X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; + d=1e100.net; s=20161025; + h=x-gm-message-state:from:to:cc:subject:date:message-id:in-reply-to + :references; + bh=oYZRhi80jnWf5lvJ9rxSq8k+5uIG9VwWaCu5KNmb2Io=; + b=EaydbtrOBjU5ArDWvIEICz9CCbooh+J6TlXBqzt2APusJL1ADHL7AiL3IFoZYivKAy + dLXHrxdC+hMc+C0rufUF1wvkTxF6SPYKcJTAUvfCoH1wkqarOXxObgmGmjeijAuUz288 + VjD5hgExmBvZ+o66edIlkKQJsAWsIuDqXusyYilSoN5QYBYSBmB530Y2yfX+6gXM5Tn7 + 9ZrYp/qiujklOWITA1apRD4MMpP2b3P32zxvG/HzP33sm4EZVf935TaUlcjJkan7UqIs + ycdaD3KcYyiAbxn6hv0RrFV+bX2V7IaurX3cnF5iGt12WTYOtC2UizjA9vjC6Ns2zS+1 + uejQ== +X-Gm-Message-State: AHQUAuY6BHyRa9wiG2h1k9f9xax3Up2BqnNZu3xueFVVQc0q4ArgMZlr + s+LA0mz9JF3YQMPyfq9jGdJkNupaJ8fp5g== +X-Google-Smtp-Source: + AHgI3IbP7F6OnN6J3jwdNsAPLLKsA8GObtlao2W2lxU4EKIzxT9TvoA9f9ljD5W+YZ8ax1/9FCi/xw== +X-Received: by 2002:adf:f487:: with SMTP id l7mr531117wro.86.1549670944704; + Fri, 08 Feb 2019 16:09:04 -0800 (PST) +Received: from localhost.localdomain (79.108.96.12.dyn.user.ono.com. + [79.108.96.12]) + by smtp.gmail.com with ESMTPSA id + 65sm10483171wrb.62.2019.02.08.16.09.03 + (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); + Fri, 08 Feb 2019 16:09:04 -0800 (PST) +From: Miguel Ojeda <miguel.ojeda.sandonis@gmail.com> +To: linux-kernel@vger.kernel.org +Cc: Miguel Ojeda <miguel.ojeda.sandonis@gmail.com>, + Laura Abbott <labbott@redhat.com>, + Martin Sebor <msebor@gcc.gnu.org>, + Arnd Bergmann <arnd@arndb.de>, + Herbert Xu <herbert@gondor.apana.org.au>, + Ard Biesheuvel <ard.biesheuvel@linaro.org>, + Krzysztof Kozlowski <krzk@kernel.org>, + Catalin Marinas <catalin.marinas@arm.com> +Subject: [PATCH 1/3] lib/crc32.c: mark crc32_le_base/__crc32c_le_base aliases + as __pure +Date: Sat, 9 Feb 2019 01:08:38 +0100 +Message-Id: <20190209000840.11018-2-miguel.ojeda.sandonis@gmail.com> +In-Reply-To: <20190209000840.11018-1-miguel.ojeda.sandonis@gmail.com> +References: <20190209000840.11018-1-miguel.ojeda.sandonis@gmail.com> +Sender: linux-kernel-owner@vger.kernel.org +Precedence: bulk +List-ID: <linux-kernel.vger.kernel.org> +X-Mailing-List: linux-kernel@vger.kernel.org + +The upcoming GCC 9 release extends the -Wmissing-attributes warnings +(enabled by -Wall) to C and aliases: it warns when particular function +attributes are missing in the aliases but not in their target. + +In particular, it triggers here because crc32_le_base/__crc32c_le_base +aren't __pure while their target crc32_le/__crc32c_le are. + +These aliases are used by architectures as a fallback in accelerated +versions of CRC32. See commit 9784d82db3eb ("lib/crc32: make core crc32() +routines weak so they can be overridden"). + +Therefore, being fallbacks, it is likely that even if the aliases +were called from C, there wouldn't be any optimizations possible. +Currently, the only user is arm64, which calls this from asm. + +Still, marking the aliases as __pure makes sense and is a good idea +for documentation purposes and possible future optimizations, +which also silences the warning. + +Acked-by: Ard Biesheuvel <ard.biesheuvel@linaro.org> +Tested-by: Laura Abbott <labbott@redhat.com> +Signed-off-by: Miguel Ojeda <miguel.ojeda.sandonis@gmail.com> +--- + lib/crc32.c | 4 ++-- + 1 file changed, 2 insertions(+), 2 deletions(-) + +diff --git a/lib/crc32.c b/lib/crc32.c +index 45b1d67a1767..4a20455d1f61 100644 +--- a/lib/crc32.c ++++ b/lib/crc32.c +@@ -206,8 +206,8 @@ u32 __pure __weak __crc32c_le(u32 crc, unsigned char const *p, size_t len) + EXPORT_SYMBOL(crc32_le); + EXPORT_SYMBOL(__crc32c_le); + +-u32 crc32_le_base(u32, unsigned char const *, size_t) __alias(crc32_le); +-u32 __crc32c_le_base(u32, unsigned char const *, size_t) __alias(__crc32c_le); ++u32 __pure crc32_le_base(u32, unsigned char const *, size_t) __alias(crc32_le); ++u32 __pure __crc32c_le_base(u32, unsigned char const *, size_t) __alias(__crc32c_le); + + /* + * This multiplies the polynomials x and y modulo the given modulus. + +From patchwork Sat Feb 9 00:08:39 2019 +Content-Type: text/plain; charset="utf-8" +MIME-Version: 1.0 +Content-Transfer-Encoding: 8bit +X-Patchwork-Submitter: Miguel Ojeda <miguel.ojeda.sandonis@gmail.com> +X-Patchwork-Id: 1040187 +Return-Path: <SRS0=1U6d=QQ=vger.kernel.org=linux-kernel-owner@kernel.org> +Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) + by smtp.lore.kernel.org (Postfix) with ESMTP id 06134C282CC + for <linux-kernel@archiver.kernel.org>; Sat, 9 Feb 2019 00:09:49 +0000 (UTC) +Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) + by mail.kernel.org (Postfix) with ESMTP id C797721841 + for <linux-kernel@archiver.kernel.org>; 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+ Fri, 08 Feb 2019 16:09:05 -0800 (PST) +From: Miguel Ojeda <miguel.ojeda.sandonis@gmail.com> +To: linux-kernel@vger.kernel.org +Cc: Miguel Ojeda <miguel.ojeda.sandonis@gmail.com>, + Martin Sebor <msebor@gcc.gnu.org>, + Arnd Bergmann <arnd@arndb.de>, + Laura Abbott <labbott@redhat.com>, + Nick Desaulniers <ndesaulniers@google.com>, + Luc Van Oostenryck <luc.vanoostenryck@gmail.com>, + Andrey Konovalov <andreyknvl@google.com>, + Kees Cook <keescook@chromium.org>, + Sean Christopherson <sean.j.christopherson@intel.com> +Subject: [PATCH 2/3] Compiler Attributes: add support for __copy (gcc >= 9) +Date: Sat, 9 Feb 2019 01:08:39 +0100 +Message-Id: <20190209000840.11018-3-miguel.ojeda.sandonis@gmail.com> +In-Reply-To: <20190209000840.11018-1-miguel.ojeda.sandonis@gmail.com> +References: <20190209000840.11018-1-miguel.ojeda.sandonis@gmail.com> +MIME-Version: 1.0 +Content-Type: text/plain; charset=UTF-8 +Sender: linux-kernel-owner@vger.kernel.org +Precedence: bulk +List-ID: <linux-kernel.vger.kernel.org> +X-Mailing-List: linux-kernel@vger.kernel.org + +From the GCC manual: + + copy + copy(function) + + The copy attribute applies the set of attributes with which function + has been declared to the declaration of the function to which + the attribute is applied. The attribute is designed for libraries + that define aliases or function resolvers that are expected + to specify the same set of attributes as their targets. The copy + attribute can be used with functions, variables, or types. However, + the kind of symbol to which the attribute is applied (either + function or variable) must match the kind of symbol to which + the argument refers. The copy attribute copies only syntactic and + semantic attributes but not attributes that affect a symbol’s + linkage or visibility such as alias, visibility, or weak. + The deprecated attribute is also not copied. + + https://gcc.gnu.org/onlinedocs/gcc/Common-Function-Attributes.html + +The upcoming GCC 9 release extends the -Wmissing-attributes warnings +(enabled by -Wall) to C and aliases: it warns when particular function +attributes are missing in the aliases but not in their target, e.g.: + + void __cold f(void) {} + void __alias("f") g(void); + +diagnoses: + + warning: 'g' specifies less restrictive attribute than + its target 'f': 'cold' [-Wmissing-attributes] + +Using __copy(f) we can copy the __cold attribute from f to g: + + void __cold f(void) {} + void __copy(f) __alias("f") g(void); + +This attribute is most useful to deal with situations where an alias +is declared but we don't know the exact attributes the target has. + +For instance, in the kernel, the widely used module_init/exit macros +define the init/cleanup_module aliases, but those cannot be marked +always as __init/__exit since they some modules do not have their +functions marked as such. + +Suggested-by: Martin Sebor <msebor@gcc.gnu.org> +Signed-off-by: Miguel Ojeda <miguel.ojeda.sandonis@gmail.com> +Reviewed-by: Nick Desaulniers <ndesaulniers@google.com> +--- + include/linux/compiler_attributes.h | 14 ++++++++++++++ + 1 file changed, 14 insertions(+) + +diff --git a/include/linux/compiler_attributes.h b/include/linux/compiler_attributes.h +index 19f32b0c29af..6b318efd8a74 100644 +--- a/include/linux/compiler_attributes.h ++++ b/include/linux/compiler_attributes.h +@@ -34,6 +34,7 @@ + #ifndef __has_attribute + # define __has_attribute(x) __GCC4_has_attribute_##x + # define __GCC4_has_attribute___assume_aligned__ (__GNUC_MINOR__ >= 9) ++# define __GCC4_has_attribute___copy__ 0 + # define __GCC4_has_attribute___designated_init__ 0 + # define __GCC4_has_attribute___externally_visible__ 1 + # define __GCC4_has_attribute___noclone__ 1 +@@ -100,6 +101,19 @@ + */ + #define __attribute_const__ __attribute__((__const__)) + ++/* ++ * Optional: only supported since gcc >= 9 ++ * Optional: not supported by clang ++ * Optional: not supported by icc ++ * ++ * gcc: https://gcc.gnu.org/onlinedocs/gcc/Common-Function-Attributes.html#index-copy-function-attribute ++ */ ++#if __has_attribute(__copy__) ++# define __copy(symbol) __attribute__((__copy__(symbol))) ++#else ++# define __copy(symbol) ++#endif ++ + /* + * Don't. Just don't. See commit 771c035372a0 ("deprecate the '__deprecated' + * attribute warnings entirely and for good") for more information. + +From patchwork Sat Feb 9 00:08:40 2019 +Content-Type: text/plain; charset="utf-8" +MIME-Version: 1.0 +Content-Transfer-Encoding: 7bit +X-Patchwork-Submitter: Miguel Ojeda <miguel.ojeda.sandonis@gmail.com> +X-Patchwork-Id: 1040188 +Return-Path: <SRS0=1U6d=QQ=vger.kernel.org=linux-kernel-owner@kernel.org> +Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) + by smtp.lore.kernel.org (Postfix) with ESMTP id 32DFBC4151A + for <linux-kernel@archiver.kernel.org>; Sat, 9 Feb 2019 00:09:49 +0000 (UTC) +Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) + by mail.kernel.org (Postfix) with ESMTP id F415A2177B + for <linux-kernel@archiver.kernel.org>; Sat, 9 Feb 2019 00:09:48 +0000 (UTC) +Authentication-Results: mail.kernel.org; + dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com + header.b="fnSxCEl/" +Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand + id S1726952AbfBIAJK (ORCPT + <rfc822;linux-kernel@archiver.kernel.org>); + Fri, 8 Feb 2019 19:09:10 -0500 +Received: from mail-wm1-f67.google.com ([209.85.128.67]:37227 "EHLO + mail-wm1-f67.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org + with ESMTP id S1726222AbfBIAJJ (ORCPT + <rfc822;linux-kernel@vger.kernel.org>); + Fri, 8 Feb 2019 19:09:09 -0500 +Received: by mail-wm1-f67.google.com with SMTP id x10so824565wmg.2 + for <linux-kernel@vger.kernel.org>; + Fri, 08 Feb 2019 16:09:08 -0800 (PST) +DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; + d=gmail.com; s=20161025; + h=from:to:cc:subject:date:message-id:in-reply-to:references; + bh=yxdwW1DyOtKem0WF782kU0A9egQwo4Qvb/PrColHLsc=; + b=fnSxCEl/bREIP3RAd8NIp5N+R5sUUw7aoHfWroXeUgHAbdmejiO7oc5wXLAEpd6Cyp + 8XcURtp1dY/UuFEsajmGDsm1LkrPE4I1ktUNwpanSsFo2g1ULWf1wKXBOWLcQz96OHCO + 6oiWOvAOyiYggXqmUIY0QmCgVEPeHbqi2NhAxrfHPw5K2iIyg6eJdlLjheNZQe4cLR// + H3LdjPgINUDp5Y9qXSw9RThVXi/2m4QX1NSRVkcYrMqmMrksKSnIEPmCVY2DZh+IgXpd + 74G4pIpPNLg0jSx3uYpwyCYpxjFmm6YtPJU4ZuGrEPQpoSyyUFzIWYBe5q/zMDPztB2k + K8LA== +X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; + d=1e100.net; s=20161025; + h=x-gm-message-state:from:to:cc:subject:date:message-id:in-reply-to + :references; + bh=yxdwW1DyOtKem0WF782kU0A9egQwo4Qvb/PrColHLsc=; + b=qL21kr4jTNpUZHGZD8TyHhmvC5NRGgE9y5IPFZE3B5xdL0qXg0QO1v/EaOgcJOBKxl + IBiKPeG3mVZyegERqZ97HKpql3G9ZO5wLcJTChAYGS8nR/XkJrXsK8ZXkGoG2aVcMxtO + lFrflsQtbHrCZZbdhgoYJAYpT9oDRWzi1I8px5OugXDFY9Bbf8zl9ASW+FS2OYDNpcIp + 8SEnQoVP+ZZrhGbni/RJWmuXZjvahkEPE4hRG9AKgtH3GjUbMZNRFqmEa34kS0hyq2g8 + 6W2AzI4TqAzXXpL+uMH7eBYsTO3l5/CGqq8LcnKY6yEfIgJV3ktPHv+p97VPwPTRCt/3 + ssIA== +X-Gm-Message-State: AHQUAub5NqVrELwrJIP8cP/Vg6X05+ZcDkdfa2wGjXecLMafbzXuXQ0T + 7htXMP3NJ7Ag3oZrUsS7nlE= +X-Google-Smtp-Source: + AHgI3IaZloQG5Jl9/hr4QFOoadP0GpzDuRvYrquOnSQlqZ+xi9CGKN8cYjJa7a//JZ7KkKCUdA/4mw== +X-Received: by 2002:a7b:c4cb:: with SMTP id g11mr742497wmk.149.1549670947426; + Fri, 08 Feb 2019 16:09:07 -0800 (PST) +Received: from localhost.localdomain (79.108.96.12.dyn.user.ono.com. + [79.108.96.12]) + by smtp.gmail.com with ESMTPSA id + 65sm10483171wrb.62.2019.02.08.16.09.06 + (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); + Fri, 08 Feb 2019 16:09:06 -0800 (PST) +From: Miguel Ojeda <miguel.ojeda.sandonis@gmail.com> +To: Jessica Yu <jeyu@kernel.org> +Cc: Miguel Ojeda <miguel.ojeda.sandonis@gmail.com>, + Laura Abbott <labbott@redhat.com>, + Martin Sebor <msebor@gcc.gnu.org>, + Arnd Bergmann <arnd@arndb.de>, + Masahiro Yamada <yamada.masahiro@socionext.com>, + James Morris <james.morris@microsoft.com>, + Mathieu Desnoyers <mathieu.desnoyers@efficios.com>, + Borislav Petkov <bp@suse.de>, + Kees Cook <keescook@chromium.org>, + Matt Mullins <mmullins@fb.com>, + Vincent Whitchurch <vincent.whitchurch@axis.com>, + WANG Chao <chao.wang@ucloud.cn>, linux-kernel@vger.kernel.org +Subject: [PATCH 3/3] include/linux/module.h: copy __init/__exit attrs to + init/cleanup_module +Date: Sat, 9 Feb 2019 01:08:40 +0100 +Message-Id: <20190209000840.11018-4-miguel.ojeda.sandonis@gmail.com> +In-Reply-To: <20190209000840.11018-1-miguel.ojeda.sandonis@gmail.com> +References: <20190209000840.11018-1-miguel.ojeda.sandonis@gmail.com> +Sender: linux-kernel-owner@vger.kernel.org +Precedence: bulk +List-ID: <linux-kernel.vger.kernel.org> +X-Mailing-List: linux-kernel@vger.kernel.org + +The upcoming GCC 9 release extends the -Wmissing-attributes warnings +(enabled by -Wall) to C and aliases: it warns when particular function +attributes are missing in the aliases but not in their target. + +In particular, it triggers for all the init/cleanup_module +aliases in the kernel (defined by the module_init/exit macros), +ending up being very noisy. + +These aliases point to the __init/__exit functions of a module, +which are defined as __cold (among other attributes). However, +the aliases themselves do not have the __cold attribute. + +Since the compiler behaves differently when compiling a __cold +function as well as when compiling paths leading to calls +to __cold functions, the warning is trying to point out +the possibly-forgotten attribute in the alias. + +In order to keep the warning enabled, we decided to silence +this case. Ideally, we would mark the aliases directly +as __init/__exit. However, there are currently around 132 modules +in the kernel which are missing __init/__exit in their init/cleanup +functions (either because they are missing, or for other reasons, +e.g. the functions being called from somewhere else); and +a section mismatch is a hard error. + +A conservative alternative was to mark the aliases as __cold only. +However, since we would like to eventually enforce __init/__exit +to be always marked, we chose to use the new __copy function +attribute (introduced by GCC 9 as well to deal with this). +With it, we copy the attributes used by the target functions +into the aliases. This way, functions that were not marked +as __init/__exit won't have their aliases marked either, +and therefore there won't be a section mismatch. + +Note that the warning would go away marking either the extern +declaration, the definition, or both. However, we only mark +the definition of the alias, since we do not want callers +(which only see the declaration) to be compiled as if the function +was __cold (and therefore the paths leading to those calls +would be assumed to be unlikely). + +Link: https://lore.kernel.org/lkml/20190123173707.GA16603@gmail.com/ +Link: https://lore.kernel.org/lkml/20190206175627.GA20399@gmail.com/ +Suggested-by: Martin Sebor <msebor@gcc.gnu.org> +Signed-off-by: Miguel Ojeda <miguel.ojeda.sandonis@gmail.com> +--- + include/linux/module.h | 4 ++-- + 1 file changed, 2 insertions(+), 2 deletions(-) + +diff --git a/include/linux/module.h b/include/linux/module.h +index 8fa38d3e7538..f5bc4c046461 100644 +--- a/include/linux/module.h ++++ b/include/linux/module.h +@@ -129,13 +129,13 @@ extern void cleanup_module(void); + #define module_init(initfn) \ + static inline initcall_t __maybe_unused __inittest(void) \ + { return initfn; } \ +- int init_module(void) __attribute__((alias(#initfn))); ++ int init_module(void) __copy(initfn) __attribute__((alias(#initfn))); + + /* This is only required if you want to be unloadable. */ + #define module_exit(exitfn) \ + static inline exitcall_t __maybe_unused __exittest(void) \ + { return exitfn; } \ +- void cleanup_module(void) __attribute__((alias(#exitfn))); ++ void cleanup_module(void) __copy(exitfn) __attribute__((alias(#exitfn))); + + #endif + |