linux/arch/x86/kernel/vmlinux.lds.S
Jan Beulich c62e43202e x86: Fix build with older binutils and consolidate linker script
binutils prior to 2.17 can't deal with the currently possible
situation of a new segment following the per-CPU segment, but
that new segment being empty - objcopy misplaces the .bss (and
perhaps also the .brk) sections outside of any segment.

However, the current ordering of sections really just appears
to be the effect of cumulative unrelated changes; re-ordering
things allows to easily guarantee that the segment following
the per-CPU one is non-empty, and at once eliminates the need
for the bogus data.init2 segment.

Once touching this code, also use the various data section
helper macros from include/asm-generic/vmlinux.lds.h.

-v2: fix !SMP builds.

Signed-off-by: Jan Beulich <jbeulich@novell.com>
Cc: <sam@ravnborg.org>
LKML-Reference: <4A94085D02000078000119A5@vpn.id2.novell.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-08-25 15:54:16 +02:00

395 lines
8.5 KiB
ArmAsm

/*
* ld script for the x86 kernel
*
* Historic 32-bit version written by Martin Mares <mj@atrey.karlin.mff.cuni.cz>
*
* Modernisation, unification and other changes and fixes:
* Copyright (C) 2007-2009 Sam Ravnborg <sam@ravnborg.org>
*
*
* Don't define absolute symbols until and unless you know that symbol
* value is should remain constant even if kernel image is relocated
* at run time. Absolute symbols are not relocated. If symbol value should
* change if kernel is relocated, make the symbol section relative and
* put it inside the section definition.
*/
#ifdef CONFIG_X86_32
#define LOAD_OFFSET __PAGE_OFFSET
#else
#define LOAD_OFFSET __START_KERNEL_map
#endif
#include <asm-generic/vmlinux.lds.h>
#include <asm/asm-offsets.h>
#include <asm/thread_info.h>
#include <asm/page_types.h>
#include <asm/cache.h>
#include <asm/boot.h>
#undef i386 /* in case the preprocessor is a 32bit one */
OUTPUT_FORMAT(CONFIG_OUTPUT_FORMAT, CONFIG_OUTPUT_FORMAT, CONFIG_OUTPUT_FORMAT)
#ifdef CONFIG_X86_32
OUTPUT_ARCH(i386)
ENTRY(phys_startup_32)
jiffies = jiffies_64;
#else
OUTPUT_ARCH(i386:x86-64)
ENTRY(phys_startup_64)
jiffies_64 = jiffies;
#endif
PHDRS {
text PT_LOAD FLAGS(5); /* R_E */
data PT_LOAD FLAGS(7); /* RWE */
#ifdef CONFIG_X86_64
user PT_LOAD FLAGS(7); /* RWE */
#ifdef CONFIG_SMP
percpu PT_LOAD FLAGS(7); /* RWE */
#endif
init PT_LOAD FLAGS(7); /* RWE */
#endif
note PT_NOTE FLAGS(0); /* ___ */
}
SECTIONS
{
#ifdef CONFIG_X86_32
. = LOAD_OFFSET + LOAD_PHYSICAL_ADDR;
phys_startup_32 = startup_32 - LOAD_OFFSET;
#else
. = __START_KERNEL;
phys_startup_64 = startup_64 - LOAD_OFFSET;
#endif
/* Text and read-only data */
/* bootstrapping code */
.text.head : AT(ADDR(.text.head) - LOAD_OFFSET) {
_text = .;
*(.text.head)
} :text = 0x9090
/* The rest of the text */
.text : AT(ADDR(.text) - LOAD_OFFSET) {
#ifdef CONFIG_X86_32
/* not really needed, already page aligned */
. = ALIGN(PAGE_SIZE);
*(.text.page_aligned)
#endif
. = ALIGN(8);
_stext = .;
TEXT_TEXT
SCHED_TEXT
LOCK_TEXT
KPROBES_TEXT
IRQENTRY_TEXT
*(.fixup)
*(.gnu.warning)
/* End of text section */
_etext = .;
} :text = 0x9090
NOTES :text :note
/* Exception table */
. = ALIGN(16);
__ex_table : AT(ADDR(__ex_table) - LOAD_OFFSET) {
__start___ex_table = .;
*(__ex_table)
__stop___ex_table = .;
} :text = 0x9090
RO_DATA(PAGE_SIZE)
/* Data */
.data : AT(ADDR(.data) - LOAD_OFFSET) {
/* Start of data section */
_sdata = .;
/* init_task */
INIT_TASK_DATA(THREAD_SIZE)
#ifdef CONFIG_X86_32
/* 32 bit has nosave before _edata */
NOSAVE_DATA
#endif
PAGE_ALIGNED_DATA(PAGE_SIZE)
*(.data.idt)
CACHELINE_ALIGNED_DATA(CONFIG_X86_L1_CACHE_BYTES)
DATA_DATA
CONSTRUCTORS
/* rarely changed data like cpu maps */
READ_MOSTLY_DATA(CONFIG_X86_INTERNODE_CACHE_BYTES)
/* End of data section */
_edata = .;
} :data
#ifdef CONFIG_X86_64
#define VSYSCALL_ADDR (-10*1024*1024)
#define VSYSCALL_PHYS_ADDR ((LOADADDR(.data) + SIZEOF(.data) + \
PAGE_SIZE - 1) & ~(PAGE_SIZE - 1))
#define VSYSCALL_VIRT_ADDR ((ADDR(.data) + SIZEOF(.data) + \
PAGE_SIZE - 1) & ~(PAGE_SIZE - 1))
#define VLOAD_OFFSET (VSYSCALL_ADDR - VSYSCALL_PHYS_ADDR)
#define VLOAD(x) (ADDR(x) - VLOAD_OFFSET)
#define VVIRT_OFFSET (VSYSCALL_ADDR - VSYSCALL_VIRT_ADDR)
#define VVIRT(x) (ADDR(x) - VVIRT_OFFSET)
. = VSYSCALL_ADDR;
.vsyscall_0 : AT(VSYSCALL_PHYS_ADDR) {
*(.vsyscall_0)
} :user
__vsyscall_0 = VSYSCALL_VIRT_ADDR;
. = ALIGN(CONFIG_X86_L1_CACHE_BYTES);
.vsyscall_fn : AT(VLOAD(.vsyscall_fn)) {
*(.vsyscall_fn)
}
. = ALIGN(CONFIG_X86_L1_CACHE_BYTES);
.vsyscall_gtod_data : AT(VLOAD(.vsyscall_gtod_data)) {
*(.vsyscall_gtod_data)
}
vsyscall_gtod_data = VVIRT(.vsyscall_gtod_data);
.vsyscall_clock : AT(VLOAD(.vsyscall_clock)) {
*(.vsyscall_clock)
}
vsyscall_clock = VVIRT(.vsyscall_clock);
.vsyscall_1 ADDR(.vsyscall_0) + 1024: AT(VLOAD(.vsyscall_1)) {
*(.vsyscall_1)
}
.vsyscall_2 ADDR(.vsyscall_0) + 2048: AT(VLOAD(.vsyscall_2)) {
*(.vsyscall_2)
}
.vgetcpu_mode : AT(VLOAD(.vgetcpu_mode)) {
*(.vgetcpu_mode)
}
vgetcpu_mode = VVIRT(.vgetcpu_mode);
. = ALIGN(CONFIG_X86_L1_CACHE_BYTES);
.jiffies : AT(VLOAD(.jiffies)) {
*(.jiffies)
}
jiffies = VVIRT(.jiffies);
.vsyscall_3 ADDR(.vsyscall_0) + 3072: AT(VLOAD(.vsyscall_3)) {
*(.vsyscall_3)
}
. = VSYSCALL_VIRT_ADDR + PAGE_SIZE;
#undef VSYSCALL_ADDR
#undef VSYSCALL_PHYS_ADDR
#undef VSYSCALL_VIRT_ADDR
#undef VLOAD_OFFSET
#undef VLOAD
#undef VVIRT_OFFSET
#undef VVIRT
#endif /* CONFIG_X86_64 */
/* Init code and data - will be freed after init */
. = ALIGN(PAGE_SIZE);
.init.begin : AT(ADDR(.init.begin) - LOAD_OFFSET) {
__init_begin = .; /* paired with __init_end */
}
#if defined(CONFIG_X86_64) && defined(CONFIG_SMP)
/*
* percpu offsets are zero-based on SMP. PERCPU_VADDR() changes the
* output PHDR, so the next output section - .init.text - should
* start another segment - init.
*/
PERCPU_VADDR(0, :percpu)
#endif
.init.text : AT(ADDR(.init.text) - LOAD_OFFSET) {
_sinittext = .;
INIT_TEXT
_einittext = .;
}
#ifdef CONFIG_X86_64
:init
#endif
.init.data : AT(ADDR(.init.data) - LOAD_OFFSET) {
INIT_DATA
}
. = ALIGN(16);
.init.setup : AT(ADDR(.init.setup) - LOAD_OFFSET) {
__setup_start = .;
*(.init.setup)
__setup_end = .;
}
.initcall.init : AT(ADDR(.initcall.init) - LOAD_OFFSET) {
__initcall_start = .;
INITCALLS
__initcall_end = .;
}
.con_initcall.init : AT(ADDR(.con_initcall.init) - LOAD_OFFSET) {
__con_initcall_start = .;
*(.con_initcall.init)
__con_initcall_end = .;
}
.x86_cpu_dev.init : AT(ADDR(.x86_cpu_dev.init) - LOAD_OFFSET) {
__x86_cpu_dev_start = .;
*(.x86_cpu_dev.init)
__x86_cpu_dev_end = .;
}
SECURITY_INIT
. = ALIGN(8);
.parainstructions : AT(ADDR(.parainstructions) - LOAD_OFFSET) {
__parainstructions = .;
*(.parainstructions)
__parainstructions_end = .;
}
. = ALIGN(8);
.altinstructions : AT(ADDR(.altinstructions) - LOAD_OFFSET) {
__alt_instructions = .;
*(.altinstructions)
__alt_instructions_end = .;
}
.altinstr_replacement : AT(ADDR(.altinstr_replacement) - LOAD_OFFSET) {
*(.altinstr_replacement)
}
/*
* .exit.text is discard at runtime, not link time, to deal with
* references from .altinstructions and .eh_frame
*/
.exit.text : AT(ADDR(.exit.text) - LOAD_OFFSET) {
EXIT_TEXT
}
.exit.data : AT(ADDR(.exit.data) - LOAD_OFFSET) {
EXIT_DATA
}
#ifdef CONFIG_BLK_DEV_INITRD
. = ALIGN(PAGE_SIZE);
.init.ramfs : AT(ADDR(.init.ramfs) - LOAD_OFFSET) {
__initramfs_start = .;
*(.init.ramfs)
__initramfs_end = .;
}
#endif
#if !defined(CONFIG_X86_64) || !defined(CONFIG_SMP)
PERCPU(PAGE_SIZE)
#endif
. = ALIGN(PAGE_SIZE);
/* freed after init ends here */
.init.end : AT(ADDR(.init.end) - LOAD_OFFSET) {
__init_end = .;
}
/*
* smp_locks might be freed after init
* start/end must be page aligned
*/
. = ALIGN(PAGE_SIZE);
.smp_locks : AT(ADDR(.smp_locks) - LOAD_OFFSET) {
__smp_locks = .;
*(.smp_locks)
__smp_locks_end = .;
. = ALIGN(PAGE_SIZE);
}
#ifdef CONFIG_X86_64
.data_nosave : AT(ADDR(.data_nosave) - LOAD_OFFSET) {
NOSAVE_DATA
}
#endif
/* BSS */
. = ALIGN(PAGE_SIZE);
.bss : AT(ADDR(.bss) - LOAD_OFFSET) {
__bss_start = .;
*(.bss.page_aligned)
*(.bss)
. = ALIGN(4);
__bss_stop = .;
}
. = ALIGN(PAGE_SIZE);
.brk : AT(ADDR(.brk) - LOAD_OFFSET) {
__brk_base = .;
. += 64 * 1024; /* 64k alignment slop space */
*(.brk_reservation) /* areas brk users have reserved */
__brk_limit = .;
}
.end : AT(ADDR(.end) - LOAD_OFFSET) {
_end = .;
}
/* Sections to be discarded */
/DISCARD/ : {
*(.exitcall.exit)
*(.eh_frame)
*(.discard)
}
STABS_DEBUG
DWARF_DEBUG
}
#ifdef CONFIG_X86_32
. = ASSERT((_end - LOAD_OFFSET <= KERNEL_IMAGE_SIZE),
"kernel image bigger than KERNEL_IMAGE_SIZE");
#else
/*
* Per-cpu symbols which need to be offset from __per_cpu_load
* for the boot processor.
*/
#define INIT_PER_CPU(x) init_per_cpu__##x = per_cpu__##x + __per_cpu_load
INIT_PER_CPU(gdt_page);
INIT_PER_CPU(irq_stack_union);
/*
* Build-time check on the image size:
*/
. = ASSERT((_end - _text <= KERNEL_IMAGE_SIZE),
"kernel image bigger than KERNEL_IMAGE_SIZE");
#ifdef CONFIG_SMP
. = ASSERT((per_cpu__irq_stack_union == 0),
"irq_stack_union is not at start of per-cpu area");
#endif
#endif /* CONFIG_X86_32 */
#ifdef CONFIG_KEXEC
#include <asm/kexec.h>
. = ASSERT(kexec_control_code_size <= KEXEC_CONTROL_CODE_MAX_SIZE,
"kexec control code size is too big");
#endif