From 01ba2bdc6b639764745ff678caf3fb9e5bcd745a Mon Sep 17 00:00:00 2001 From: Sam Ravnborg Date: Sun, 20 Jan 2008 14:15:03 +0100 Subject: all archs: consolidate init and exit sections in vmlinux.lds.h This patch consolidate all definitions of .init.text, .init.data and .exit.text, .exit.data section definitions in the generic vmlinux.lds.h. This is a preparational patch - alone it does not buy us much good. Signed-off-by: Sam Ravnborg --- include/asm-generic/vmlinux.lds.h | 7 +++++++ 1 file changed, 7 insertions(+) (limited to 'include/asm-generic') diff --git a/include/asm-generic/vmlinux.lds.h b/include/asm-generic/vmlinux.lds.h index 9f584cc5c5f..ae0166e8349 100644 --- a/include/asm-generic/vmlinux.lds.h +++ b/include/asm-generic/vmlinux.lds.h @@ -183,6 +183,13 @@ *(.kprobes.text) \ VMLINUX_SYMBOL(__kprobes_text_end) = .; +/* init and exit section handling */ +#define INIT_TEXT *(.init.text) +#define INIT_DATA *(.init.data) +#define EXIT_TEXT *(.exit.text) +#define EXIT_DATA *(.exit.data) + + /* DWARF debug sections. Symbols in the DWARF debugging sections are relative to the beginning of the section so we begin them at 0. */ -- cgit v1.2.3-70-g09d2 From eb8f689046b857874e964463619f09df06d59fad Mon Sep 17 00:00:00 2001 From: Sam Ravnborg Date: Sun, 20 Jan 2008 20:07:28 +0100 Subject: Use separate sections for __dev/__cpu/__mem code/data Introducing separate sections for __dev* (HOTPLUG), __cpu* (HOTPLUG_CPU) and __mem* (MEMORY_HOTPLUG) allows us to do a much more reliable Section mismatch check in modpost. We are no longer dependent on the actual configuration of for example HOTPLUG. This has the effect that all users see much more Section mismatch warnings than before because they were almost all hidden when HOTPLUG was enabled. The advantage of this is that when building a piece of code then it is much more likely that the Section mismatch errors are spotted and the warnings will be felt less random of nature. Signed-off-by: Sam Ravnborg Cc: Greg KH Cc: Randy Dunlap Cc: Adrian Bunk --- include/asm-generic/vmlinux.lds.h | 88 ++++++++++++++++++++++++++++++++++++--- include/linux/init.h | 77 +++++++++++++++++----------------- scripts/mod/modpost.c | 54 +++++++++++++++++------- 3 files changed, 159 insertions(+), 60 deletions(-) (limited to 'include/asm-generic') diff --git a/include/asm-generic/vmlinux.lds.h b/include/asm-generic/vmlinux.lds.h index ae0166e8349..e0a56fb8f81 100644 --- a/include/asm-generic/vmlinux.lds.h +++ b/include/asm-generic/vmlinux.lds.h @@ -9,10 +9,46 @@ /* Align . to a 8 byte boundary equals to maximum function alignment. */ #define ALIGN_FUNCTION() . = ALIGN(8) +/* The actual configuration determine if the init/exit sections + * are handled as text/data or they can be discarded (which + * often happens at runtime) + */ +#ifdef CONFIG_HOTPLUG +#define DEV_KEEP(sec) *(.dev##sec) +#define DEV_DISCARD(sec) +#else +#define DEV_KEEP(sec) +#define DEV_DISCARD(sec) *(.dev##sec) +#endif + +#ifdef CONFIG_HOTPLUG_CPU +#define CPU_KEEP(sec) *(.cpu##sec) +#define CPU_DISCARD(sec) +#else +#define CPU_KEEP(sec) +#define CPU_DISCARD(sec) *(.cpu##sec) +#endif + +#if defined(CONFIG_MEMORY_HOTPLUG) || defined(CONFIG_ACPI_HOTPLUG_MEMORY) \ + || defined(CONFIG_ACPI_HOTPLUG_MEMORY_MODULE) +#define MEM_KEEP(sec) *(.mem##sec) +#define MEM_DISCARD(sec) +#else +#define MEM_KEEP(sec) +#define MEM_DISCARD(sec) *(.mem##sec) +#endif + + /* .data section */ #define DATA_DATA \ *(.data) \ *(.data.init.refok) \ + DEV_KEEP(init.data) \ + DEV_KEEP(exit.data) \ + CPU_KEEP(init.data) \ + CPU_KEEP(exit.data) \ + MEM_KEEP(init.data) \ + MEM_KEEP(exit.data) \ . = ALIGN(8); \ VMLINUX_SYMBOL(__start___markers) = .; \ *(__markers) \ @@ -132,6 +168,16 @@ *(__ksymtab_strings) \ } \ \ + /* __*init sections */ \ + __init_rodata : AT(ADDR(__init_rodata) - LOAD_OFFSET) { \ + DEV_KEEP(init.rodata) \ + DEV_KEEP(exit.rodata) \ + CPU_KEEP(init.rodata) \ + CPU_KEEP(exit.rodata) \ + MEM_KEEP(init.rodata) \ + MEM_KEEP(exit.rodata) \ + } \ + \ /* Built-in module parameters. */ \ __param : AT(ADDR(__param) - LOAD_OFFSET) { \ VMLINUX_SYMBOL(__start___param) = .; \ @@ -139,7 +185,6 @@ VMLINUX_SYMBOL(__stop___param) = .; \ VMLINUX_SYMBOL(__end_rodata) = .; \ } \ - \ . = ALIGN((align)); /* RODATA provided for backward compatibility. @@ -159,7 +204,14 @@ ALIGN_FUNCTION(); \ *(.text) \ *(.text.init.refok) \ - *(.exit.text.refok) + *(.exit.text.refok) \ + DEV_KEEP(init.text) \ + DEV_KEEP(exit.text) \ + CPU_KEEP(init.text) \ + CPU_KEEP(exit.text) \ + MEM_KEEP(init.text) \ + MEM_KEEP(exit.text) + /* sched.text is aling to function alignment to secure we have same * address even at second ld pass when generating System.map */ @@ -184,11 +236,35 @@ VMLINUX_SYMBOL(__kprobes_text_end) = .; /* init and exit section handling */ -#define INIT_TEXT *(.init.text) -#define INIT_DATA *(.init.data) -#define EXIT_TEXT *(.exit.text) -#define EXIT_DATA *(.exit.data) +#define INIT_DATA \ + *(.init.data) \ + DEV_DISCARD(init.data) \ + DEV_DISCARD(init.rodata) \ + CPU_DISCARD(init.data) \ + CPU_DISCARD(init.rodata) \ + MEM_DISCARD(init.data) \ + MEM_DISCARD(init.rodata) + +#define INIT_TEXT \ + *(.init.text) \ + DEV_DISCARD(init.text) \ + CPU_DISCARD(init.text) \ + MEM_DISCARD(init.text) + +#define EXIT_DATA \ + *(.exit.data) \ + DEV_DISCARD(exit.data) \ + DEV_DISCARD(exit.rodata) \ + CPU_DISCARD(exit.data) \ + CPU_DISCARD(exit.rodata) \ + MEM_DISCARD(exit.data) \ + MEM_DISCARD(exit.rodata) +#define EXIT_TEXT \ + *(.exit.text) \ + DEV_DISCARD(exit.text) \ + CPU_DISCARD(exit.text) \ + MEM_DISCARD(exit.text) /* DWARF debug sections. Symbols in the DWARF debugging sections are relative to diff --git a/include/linux/init.h b/include/linux/init.h index 99807681840..dcb66c76bd4 100644 --- a/include/linux/init.h +++ b/include/linux/init.h @@ -60,18 +60,54 @@ #define __exit_refok noinline __section(.exit.text.refok) #ifdef MODULE -#define __exit __section(.exit.text) __cold +#define __exitused #else -#define __exit __attribute_used__ __section(.exit.text) __cold +#define __exitused __used #endif +#define __exit __section(.exit.text) __exitused __cold + +/* Used for HOTPLUG */ +#define __devinit __section(.devinit.text) __cold +#define __devinitdata __section(.devinit.data) +#define __devinitconst __section(.devinit.rodata) +#define __devexit __section(.devexit.text) __exitused __cold +#define __devexitdata __section(.devexit.data) +#define __devexitconst __section(.devexit.rodata) + +/* Used for HOTPLUG_CPU */ +#define __cpuinit __section(.cpuinit.text) __cold +#define __cpuinitdata __section(.cpuinit.data) +#define __cpuinitconst __section(.cpuinit.rodata) +#define __cpuexit __section(.cpuexit.text) __exitused __cold +#define __cpuexitdata __section(.cpuexit.data) +#define __cpuexitconst __section(.cpuexit.rodata) + +/* Used for MEMORY_HOTPLUG */ +#define __meminit __section(.meminit.text) __cold +#define __meminitdata __section(.meminit.data) +#define __meminitconst __section(.meminit.rodata) +#define __memexit __section(.memexit.text) __exitused __cold +#define __memexitdata __section(.memexit.data) +#define __memexitconst __section(.memexit.rodata) + /* For assembly routines */ #define __INIT .section ".init.text","ax" #define __INIT_REFOK .section ".text.init.refok","ax" #define __FINIT .previous + #define __INITDATA .section ".init.data","aw" #define __INITDATA_REFOK .section ".data.init.refok","aw" +#define __DEVINIT .section ".devinit.text", "ax" +#define __DEVINITDATA .section ".devinit.data", "aw" + +#define __CPUINIT .section ".cpuinit.text", "ax" +#define __CPUINITDATA .section ".cpuinit.data", "aw" + +#define __MEMINIT .section ".meminit.text", "ax" +#define __MEMINITDATA .section ".meminit.data", "aw" + #ifndef __ASSEMBLY__ /* * Used for initialization calls.. @@ -254,43 +290,6 @@ void __init parse_early_param(void); #define __initdata_or_module __initdata #endif /*CONFIG_MODULES*/ -#ifdef CONFIG_HOTPLUG -#define __devinit -#define __devinitdata -#define __devexit -#define __devexitdata -#else -#define __devinit __init -#define __devinitdata __initdata -#define __devexit __exit -#define __devexitdata __exitdata -#endif - -#ifdef CONFIG_HOTPLUG_CPU -#define __cpuinit -#define __cpuinitdata -#define __cpuexit -#define __cpuexitdata -#else -#define __cpuinit __init -#define __cpuinitdata __initdata -#define __cpuexit __exit -#define __cpuexitdata __exitdata -#endif - -#if defined(CONFIG_MEMORY_HOTPLUG) || defined(CONFIG_ACPI_HOTPLUG_MEMORY) \ - || defined(CONFIG_ACPI_HOTPLUG_MEMORY_MODULE) -#define __meminit -#define __meminitdata -#define __memexit -#define __memexitdata -#else -#define __meminit __init -#define __meminitdata __initdata -#define __memexit __exit -#define __memexitdata __exitdata -#endif - /* Functions marked as __devexit may be discarded at kernel link time, depending on config options. Newer versions of binutils detect references from retained sections to discarded sections and flag an error. Pointers to diff --git a/scripts/mod/modpost.c b/scripts/mod/modpost.c index 986513dcd70..730b321680c 100644 --- a/scripts/mod/modpost.c +++ b/scripts/mod/modpost.c @@ -670,27 +670,41 @@ int match(const char *sym, const char * const pat[]) static const char *section_white_list[] = { ".debug*", ".stab*", ".note*", ".got*", ".toc*", NULL }; -#define INIT_DATA_SECTIONS ".init.data$" -#define EXIT_DATA_SECTIONS ".exit.data$" +#define ALL_INIT_DATA_SECTIONS \ + ".init.data$", ".devinit.data$", ".cpuinit.data$", ".meminit.data$" +#define ALL_EXIT_DATA_SECTIONS \ + ".exit.data$", ".devexit.data$", ".cpuexit.data$", ".memexit.data$" -#define INIT_TEXT_SECTIONS ".init.text$" -#define EXIT_TEXT_SECTIONS ".exit.text$" +#define ALL_INIT_TEXT_SECTIONS \ + ".init.text$", ".devinit.text$", ".cpuinit.text$", ".meminit.text$" +#define ALL_EXIT_TEXT_SECTIONS \ + ".exit.text$", ".devexit.text$", ".cpuexit.text$", ".memexit.text$" -#define INIT_SECTIONS INIT_DATA_SECTIONS, INIT_TEXT_SECTIONS -#define EXIT_SECTIONS EXIT_DATA_SECTIONS, EXIT_TEXT_SECTIONS +#define ALL_INIT_SECTIONS ALL_INIT_DATA_SECTIONS, ALL_INIT_TEXT_SECTIONS +#define ALL_EXIT_SECTIONS ALL_EXIT_DATA_SECTIONS, ALL_EXIT_TEXT_SECTIONS #define DATA_SECTIONS ".data$", ".data.rel$" #define TEXT_SECTIONS ".text$" +#define INIT_SECTIONS ".init.data$", ".init.text$" +#define DEV_INIT_SECTIONS ".devinit.data$", ".devinit.text$" +#define CPU_INIT_SECTIONS ".cpuinit.data$", ".cpuinit.text$" +#define MEM_INIT_SECTIONS ".meminit.data$", ".meminit.text$" + +#define EXIT_SECTIONS ".exit.data$", ".exit.text$" +#define DEV_EXIT_SECTIONS ".devexit.data$", ".devexit.text$" +#define CPU_EXIT_SECTIONS ".cpuexit.data$", ".cpuexit.text$" +#define MEM_EXIT_SECTIONS ".memexit.data$", ".memexit.text$" + /* init data sections */ -static const char *init_data_sections[] = { INIT_DATA_SECTIONS, NULL }; +static const char *init_data_sections[] = { ALL_INIT_DATA_SECTIONS, NULL }; /* all init sections */ -static const char *init_sections[] = { INIT_SECTIONS, NULL }; +static const char *init_sections[] = { ALL_INIT_SECTIONS, NULL }; /* All init and exit sections (code + data) */ static const char *init_exit_sections[] = - {INIT_SECTIONS, EXIT_SECTIONS, NULL }; + {ALL_INIT_SECTIONS, ALL_EXIT_SECTIONS, NULL }; /* data section */ static const char *data_sections[] = { DATA_SECTIONS, NULL }; @@ -734,22 +748,32 @@ const struct sectioncheck sectioncheck[] = { */ { .fromsec = { TEXT_SECTIONS, DATA_SECTIONS, NULL }, - .tosec = { INIT_SECTIONS, EXIT_SECTIONS, NULL } + .tosec = { ALL_INIT_SECTIONS, ALL_EXIT_SECTIONS, NULL } +}, +/* Do not reference init code/data from devinit/cpuinit/meminit code/data */ +{ + .fromsec = { DEV_INIT_SECTIONS, CPU_INIT_SECTIONS, MEM_INIT_SECTIONS, NULL }, + .tosec = { INIT_SECTIONS, NULL } +}, +/* Do not reference exit code/data from devexit/cpuexit/memexit code/data */ +{ + .fromsec = { DEV_EXIT_SECTIONS, CPU_EXIT_SECTIONS, MEM_EXIT_SECTIONS, NULL }, + .tosec = { EXIT_SECTIONS, NULL } }, /* Do not use exit code/data from init code */ { - .fromsec = { INIT_SECTIONS, NULL }, - .tosec = { EXIT_SECTIONS, NULL }, + .fromsec = { ALL_INIT_SECTIONS, NULL }, + .tosec = { ALL_EXIT_SECTIONS, NULL }, }, /* Do not use init code/data from exit code */ { - .fromsec = { EXIT_SECTIONS, NULL }, - .tosec = { INIT_SECTIONS, NULL } + .fromsec = { ALL_EXIT_SECTIONS, NULL }, + .tosec = { ALL_INIT_SECTIONS, NULL } }, /* Do not export init/exit functions or data */ { .fromsec = { "__ksymtab*", NULL }, - .tosec = { INIT_SECTIONS, EXIT_SECTIONS, NULL } + .tosec = { ALL_INIT_SECTIONS, ALL_EXIT_SECTIONS, NULL } } }; -- cgit v1.2.3-70-g09d2 From 1a3fb6d481689d0482eacadcbe3205b49b423c11 Mon Sep 17 00:00:00 2001 From: Adrian Bunk Date: Thu, 24 Jan 2008 22:20:18 +0100 Subject: asm-generic/vmlix.lds.h: simplify __mem{init,exit}* dependencies Simplify the dependencies on __mem{init,exit}* (ACPI_HOTPLUG_MEMORY requires MEMORY_HOTPLUG). Signed-off-by: Adrian Bunk Signed-off-by: Sam Ravnborg --- include/asm-generic/vmlinux.lds.h | 3 +-- 1 file changed, 1 insertion(+), 2 deletions(-) (limited to 'include/asm-generic') diff --git a/include/asm-generic/vmlinux.lds.h b/include/asm-generic/vmlinux.lds.h index e0a56fb8f81..29485305370 100644 --- a/include/asm-generic/vmlinux.lds.h +++ b/include/asm-generic/vmlinux.lds.h @@ -29,8 +29,7 @@ #define CPU_DISCARD(sec) *(.cpu##sec) #endif -#if defined(CONFIG_MEMORY_HOTPLUG) || defined(CONFIG_ACPI_HOTPLUG_MEMORY) \ - || defined(CONFIG_ACPI_HOTPLUG_MEMORY_MODULE) +#if defined(CONFIG_MEMORY_HOTPLUG) #define MEM_KEEP(sec) *(.mem##sec) #define MEM_DISCARD(sec) #else -- cgit v1.2.3-70-g09d2 From 312b1485fb509c9bc32eda28ad29537896658cb8 Mon Sep 17 00:00:00 2001 From: Sam Ravnborg Date: Mon, 28 Jan 2008 20:21:15 +0100 Subject: Introduce new section reference annotations tags: __ref, __refdata, __refconst Today we have the following annotations for functions/data referencing __init/__exit functions / data: __init_refok => for init functions __initdata_refok => for init data __exit_refok => for exit functions There is really no difference between the __init and __exit versions and simplify it and to introduce a shorter annotation the following new annotations are introduced: __ref => for functions (code) that references __*init / __*exit __refdata => for variables __refconst => for const variables Whit this annotation is it more obvious what the annotation is for and there is no longer the arbitary division between __init and __exit code. The mechanishm is the same as before - a special section is created which is made part of the usual sections in the linker script. We will start to see annotations like this: -static struct pci_serial_quirk pci_serial_quirks[] = { +static const struct pci_serial_quirk pci_serial_quirks[] __refconst = { ----------------- -static struct notifier_block __cpuinitdata cpuid_class_cpu_notifier = +static struct notifier_block cpuid_class_cpu_notifier __refdata = ---------------- -static int threshold_cpu_callback(struct notifier_block *nfb, +static int __ref threshold_cpu_callback(struct notifier_block *nfb, [The above is just random samples]. Note: No modifications were needed in modpost to support the new sections due to the newly introduced blacklisting. Signed-off-by: Sam Ravnborg --- include/asm-generic/vmlinux.lds.h | 3 +++ include/linux/init.h | 34 +++++++++++++++++++++++++++------- 2 files changed, 30 insertions(+), 7 deletions(-) (limited to 'include/asm-generic') diff --git a/include/asm-generic/vmlinux.lds.h b/include/asm-generic/vmlinux.lds.h index 29485305370..76df771be58 100644 --- a/include/asm-generic/vmlinux.lds.h +++ b/include/asm-generic/vmlinux.lds.h @@ -42,6 +42,7 @@ #define DATA_DATA \ *(.data) \ *(.data.init.refok) \ + *(.ref.data) \ DEV_KEEP(init.data) \ DEV_KEEP(exit.data) \ CPU_KEEP(init.data) \ @@ -169,6 +170,7 @@ \ /* __*init sections */ \ __init_rodata : AT(ADDR(__init_rodata) - LOAD_OFFSET) { \ + *(.ref.rodata) \ DEV_KEEP(init.rodata) \ DEV_KEEP(exit.rodata) \ CPU_KEEP(init.rodata) \ @@ -202,6 +204,7 @@ #define TEXT_TEXT \ ALIGN_FUNCTION(); \ *(.text) \ + *(.ref.text) \ *(.text.init.refok) \ *(.exit.text.refok) \ DEV_KEEP(init.text) \ diff --git a/include/linux/init.h b/include/linux/init.h index dde1eaa7766..2efbda01674 100644 --- a/include/linux/init.h +++ b/include/linux/init.h @@ -52,12 +52,26 @@ * when early init has completed so all such references are potential bugs. * For exit sections the same issue exists. * The following markers are used for the cases where the reference to - * the init/exit section (code or data) is valid and will teach modpost - * not to issue a warning. + * the *init / *exit section (code or data) is valid and will teach + * modpost not to issue a warning. * The markers follow same syntax rules as __init / __initdata. */ -#define __init_refok noinline __section(.text.init.refok) -#define __initdata_refok __section(.data.init.refok) -#define __exit_refok noinline __section(.exit.text.refok) +#define __ref __section(.ref.text) noinline +#define __refdata __section(.ref.data) +#define __refconst __section(.ref.rodata) + +/* backward compatibility note + * A few places hardcode the old section names: + * .text.init.refok + * .data.init.refok + * .exit.text.refok + * They should be converted to use the defines from this file + */ + +/* compatibility defines */ +#define __init_refok __ref +#define __initdata_refok __refdata +#define __exit_refok __ref + #ifdef MODULE #define __exitused @@ -93,11 +107,9 @@ /* For assembly routines */ #define __INIT .section ".init.text","ax" -#define __INIT_REFOK .section ".text.init.refok","ax" #define __FINIT .previous #define __INITDATA .section ".init.data","aw" -#define __INITDATA_REFOK .section ".data.init.refok","aw" #define __DEVINIT .section ".devinit.text", "ax" #define __DEVINITDATA .section ".devinit.data", "aw" @@ -108,6 +120,14 @@ #define __MEMINIT .section ".meminit.text", "ax" #define __MEMINITDATA .section ".meminit.data", "aw" +/* silence warnings when references are OK */ +#define __REF .section ".ref.text", "ax" +#define __REFDATA .section ".ref.data", "aw" +#define __REFCONST .section ".ref.rodata", "aw" +/* backward compatibility */ +#define __INIT_REFOK .section __REF +#define __INITDATA_REFOK .section __REFDATA + #ifndef __ASSEMBLY__ /* * Used for initialization calls.. -- cgit v1.2.3-70-g09d2