From 075681e85c5c089441355e290e1e1ca3bbf60617 Mon Sep 17 00:00:00 2001 From: Cristinel Panfir Date: Tue, 3 Dec 2019 16:28:02 +0200 Subject: [PATCH] linux-imx: Added backport patches to fix building with gcc 9 - added patches related copy attribute support - renamed imx_v7_defconfig and use more simplifed recipe from upstream Signed-off-by: Cristinel Panfir --- ...ributes-add-support-for-__copy-gcc-9.patch | 98 +++++++++++++++++++ ...dule.h-copy-__init-__exit-attrs-to-i.patch | 83 ++++++++++++++++ .../imx/{imx_v7_defconfig => defconfig} | 0 recipes-kernel/linux/linux-imx_4.19.35.bb | 24 ++--- 4 files changed, 188 insertions(+), 17 deletions(-) create mode 100644 recipes-kernel/linux/linux-imx-4.19.35/0001-Compiler-Attributes-add-support-for-__copy-gcc-9.patch create mode 100644 recipes-kernel/linux/linux-imx-4.19.35/0002-include-linux-module.h-copy-__init-__exit-attrs-to-i.patch rename recipes-kernel/linux/linux-imx-4.19.35/imx/{imx_v7_defconfig => defconfig} (100%) diff --git a/recipes-kernel/linux/linux-imx-4.19.35/0001-Compiler-Attributes-add-support-for-__copy-gcc-9.patch b/recipes-kernel/linux/linux-imx-4.19.35/0001-Compiler-Attributes-add-support-for-__copy-gcc-9.patch new file mode 100644 index 00000000..d69ede46 --- /dev/null +++ b/recipes-kernel/linux/linux-imx-4.19.35/0001-Compiler-Attributes-add-support-for-__copy-gcc-9.patch @@ -0,0 +1,98 @@ +From 2a0f719db71c69f5a04fcfc164f12f58f3ee7703 Mon Sep 17 00:00:00 2001 +From: Miguel Ojeda +Date: Fri, 8 Feb 2019 23:51:05 +0100 +Subject: [PATCH] Compiler Attributes: add support for __copy (gcc >= 9) +MIME-Version: 1.0 +Content-Type: text/plain; charset=UTF-8 +Content-Transfer-Encoding: 8bit + +commit c0d9782f5b6d7157635ae2fd782a4b27d55a6013 upstream. + +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 some modules do not have their +functions marked as such. + +Suggested-by: Martin Sebor +Reviewed-by: Nick Desaulniers +Signed-off-by: Miguel Ojeda +Signed-off-by: Stefan Agner +Signed-off-by: Greg Kroah-Hartman +--- + include/linux/compiler-gcc.h | 4 ++++ + include/linux/compiler_types.h | 4 ++++ + 2 files changed, 8 insertions(+) + +diff --git a/include/linux/compiler-gcc.h b/include/linux/compiler-gcc.h +index a8ff0ca..3ebee1c 100644 +--- a/include/linux/compiler-gcc.h ++++ b/include/linux/compiler-gcc.h +@@ -201,6 +201,10 @@ + #define COMPILER_HAS_GENERIC_BUILTIN_OVERFLOW 1 + #endif + ++#if GCC_VERSION >= 90100 ++#define __copy(symbol) __attribute__((__copy__(symbol))) ++#endif ++ + #if !defined(__noclone) + #define __noclone /* not needed */ + #endif +diff --git a/include/linux/compiler_types.h b/include/linux/compiler_types.h +index c2ded31..2b8ed70 100644 +--- a/include/linux/compiler_types.h ++++ b/include/linux/compiler_types.h +@@ -180,6 +180,10 @@ struct ftrace_likely_data { + #define __diag_GCC(version, severity, string) + #endif + ++#ifndef __copy ++# define __copy(symbol) ++#endif ++ + #define __diag_push() __diag(push) + #define __diag_pop() __diag(pop) + +-- +2.7.4 + diff --git a/recipes-kernel/linux/linux-imx-4.19.35/0002-include-linux-module.h-copy-__init-__exit-attrs-to-i.patch b/recipes-kernel/linux/linux-imx-4.19.35/0002-include-linux-module.h-copy-__init-__exit-attrs-to-i.patch new file mode 100644 index 00000000..78619a5e --- /dev/null +++ b/recipes-kernel/linux/linux-imx-4.19.35/0002-include-linux-module.h-copy-__init-__exit-attrs-to-i.patch @@ -0,0 +1,83 @@ +From 9468870f7cbdb4d7ca828d02d4ff507c01fe591d Mon Sep 17 00:00:00 2001 +From: Miguel Ojeda +Date: Sat, 19 Jan 2019 20:59:34 +0100 +Subject: [PATCH] include/linux/module.h: copy __init/__exit attrs to + init/cleanup_module + +commit a6e60d84989fa0e91db7f236eda40453b0e44afa upstream. + +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 +Acked-by: Jessica Yu +Signed-off-by: Miguel Ojeda +Signed-off-by: Stefan Agner +Signed-off-by: Greg Kroah-Hartman +--- + 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 c710446..9915397 100644 +--- a/include/linux/module.h ++++ b/include/linux/module.h +@@ -130,13 +130,13 @@ 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 + +-- +2.7.4 + diff --git a/recipes-kernel/linux/linux-imx-4.19.35/imx/imx_v7_defconfig b/recipes-kernel/linux/linux-imx-4.19.35/imx/defconfig similarity index 100% rename from recipes-kernel/linux/linux-imx-4.19.35/imx/imx_v7_defconfig rename to recipes-kernel/linux/linux-imx-4.19.35/imx/defconfig diff --git a/recipes-kernel/linux/linux-imx_4.19.35.bb b/recipes-kernel/linux/linux-imx_4.19.35.bb index 138c1178..dd69aba5 100644 --- a/recipes-kernel/linux/linux-imx_4.19.35.bb +++ b/recipes-kernel/linux/linux-imx_4.19.35.bb @@ -1,5 +1,6 @@ -# Copyright (C) 2013-2016 Freescale Semiconductor -# Copyright 2017-2018 NXP +# Copyright 2013-2016 (C) Freescale Semiconductor +# Copyright 2017-2019 (C) NXP +# Copyright 2018 (C) O.S. Systems Software LTDA. # Released under the MIT license (see COPYING.MIT for the terms) SUMMARY = "Linux Kernel provided and supported by NXP" @@ -10,27 +11,16 @@ require recipes-kernel/linux/linux-imx.inc LICENSE = "GPLv2" LIC_FILES_CHKSUM = "file://COPYING;md5=bbea815ee2795b2f4230826c0c6b8814" + DEPENDS += "lzop-native bc-native" SRCBRANCH = "imx_4.19.35_1.1.0" LOCALVERSION = "-1.1.0" -KERNEL_SRC ?= "git://source.codeaurora.org/external/imx/linux-imx.git;protocol=https" -SRC_URI = "${KERNEL_SRC};branch=${SRCBRANCH}" SRCREV = "0f9917c56d5995e1dc3bde5658e2d7bc865464de" - -S = "${WORKDIR}/git" +SRC_URI += "file://0001-Compiler-Attributes-add-support-for-__copy-gcc-9.patch \ + file://0002-include-linux-module.h-copy-__init-__exit-attrs-to-i.patch \ + " DEFAULT_PREFERENCE = "1" -DEFCONFIG = "defconfig" -DEFCONFIG_mx6 = "imx_v7_defconfig" -DEFCONFIG_mx7 = "imx_v7_defconfig" - -do_preconfigure_prepend() { - # meta-freescale/classes/fsl-kernel-localversion.bbclass requires - # defconfig in ${WORKDIR} - install -d ${B} - cp ${S}/arch/${ARCH}/configs/${DEFCONFIG} ${WORKDIR}/defconfig -} - COMPATIBLE_MACHINE = "(mx6|mx7|mx8)" -- 2.40.1