1/* 2 * ld script for the x86 kernel 3 * 4 * Historic 32-bit version written by Martin Mares <mj@atrey.karlin.mff.cuni.cz> 5 * 6 * Modernisation, unification and other changes and fixes: 7 * Copyright (C) 2007-2009 Sam Ravnborg <sam@ravnborg.org> 8 * 9 * 10 * Don't define absolute symbols until and unless you know that symbol 11 * value is should remain constant even if kernel image is relocated 12 * at run time. Absolute symbols are not relocated. If symbol value should 13 * change if kernel is relocated, make the symbol section relative and 14 * put it inside the section definition. 15 */ 16 17#ifdef CONFIG_X86_32 18#define LOAD_OFFSET __PAGE_OFFSET 19#else 20#define LOAD_OFFSET __START_KERNEL_map 21#endif 22 23#include <asm-generic/vmlinux.lds.h> 24#include <asm/asm-offsets.h> 25#include <asm/thread_info.h> 26#include <asm/page_types.h> 27#include <asm/cache.h> 28#include <asm/boot.h> 29 30#undef i386 /* in case the preprocessor is a 32bit one */ 31 32OUTPUT_FORMAT(CONFIG_OUTPUT_FORMAT, CONFIG_OUTPUT_FORMAT, CONFIG_OUTPUT_FORMAT) 33 34#ifdef CONFIG_X86_32 35OUTPUT_ARCH(i386) 36ENTRY(phys_startup_32) 37jiffies = jiffies_64; 38#else 39OUTPUT_ARCH(i386:x86-64) 40ENTRY(phys_startup_64) 41jiffies_64 = jiffies; 42#endif 43 44PHDRS { 45 text PT_LOAD FLAGS(5); /* R_E */ 46 data PT_LOAD FLAGS(7); /* RWE */ 47#ifdef CONFIG_X86_64 48 user PT_LOAD FLAGS(5); /* R_E */ 49#ifdef CONFIG_SMP 50 percpu PT_LOAD FLAGS(6); /* RW_ */ 51#endif 52 init PT_LOAD FLAGS(7); /* RWE */ 53#endif 54 note PT_NOTE FLAGS(0); /* ___ */ 55} 56 57SECTIONS 58{ 59#ifdef CONFIG_X86_32 60 . = LOAD_OFFSET + LOAD_PHYSICAL_ADDR; 61 phys_startup_32 = startup_32 - LOAD_OFFSET; 62#else 63 . = __START_KERNEL; 64 phys_startup_64 = startup_64 - LOAD_OFFSET; 65#endif 66 67 /* Text and read-only data */ 68 .text : AT(ADDR(.text) - LOAD_OFFSET) { 69 _text = .; 70 /* bootstrapping code */ 71 HEAD_TEXT 72#ifdef CONFIG_X86_32 73 . = ALIGN(PAGE_SIZE); 74 *(.text.page_aligned) 75#endif 76 . = ALIGN(8); 77 _stext = .; 78 TEXT_TEXT 79 SCHED_TEXT 80 LOCK_TEXT 81 KPROBES_TEXT 82 IRQENTRY_TEXT 83 *(.fixup) 84 *(.gnu.warning) 85 /* End of text section */ 86 _etext = .; 87 } :text = 0x9090 88 89 NOTES :text :note 90 91 EXCEPTION_TABLE(16) :text = 0x9090 92 93 RO_DATA(PAGE_SIZE) 94 95 /* Data */ 96 .data : AT(ADDR(.data) - LOAD_OFFSET) { 97 /* Start of data section */ 98 _sdata = .; 99 100 /* init_task */ 101 INIT_TASK_DATA(THREAD_SIZE) 102 103#ifdef CONFIG_X86_32 104 /* 32 bit has nosave before _edata */ 105 NOSAVE_DATA 106#endif 107 108 PAGE_ALIGNED_DATA(PAGE_SIZE) 109 110 CACHELINE_ALIGNED_DATA(CONFIG_X86_L1_CACHE_BYTES) 111 112 DATA_DATA 113 CONSTRUCTORS 114 115 /* rarely changed data like cpu maps */ 116 READ_MOSTLY_DATA(CONFIG_X86_INTERNODE_CACHE_BYTES) 117 118 /* End of data section */ 119 _edata = .; 120 } :data 121 122#ifdef CONFIG_X86_64 123 124#define VSYSCALL_ADDR (-10*1024*1024) 125 126#define VLOAD_OFFSET (VSYSCALL_ADDR - __vsyscall_0 + LOAD_OFFSET) 127#define VLOAD(x) (ADDR(x) - VLOAD_OFFSET) 128 129#define VVIRT_OFFSET (VSYSCALL_ADDR - __vsyscall_0) 130#define VVIRT(x) (ADDR(x) - VVIRT_OFFSET) 131 132 . = ALIGN(4096); 133 __vsyscall_0 = .; 134 135 . = VSYSCALL_ADDR; 136 .vsyscall_0 : AT(VLOAD(.vsyscall_0)) { 137 *(.vsyscall_0) 138 } :user 139 140 . = ALIGN(CONFIG_X86_L1_CACHE_BYTES); 141 .vsyscall_fn : AT(VLOAD(.vsyscall_fn)) { 142 *(.vsyscall_fn) 143 } 144 145 . = ALIGN(CONFIG_X86_L1_CACHE_BYTES); 146 .vsyscall_gtod_data : AT(VLOAD(.vsyscall_gtod_data)) { 147 *(.vsyscall_gtod_data) 148 } 149 150 vsyscall_gtod_data = VVIRT(.vsyscall_gtod_data); 151 .vsyscall_clock : AT(VLOAD(.vsyscall_clock)) { 152 *(.vsyscall_clock) 153 } 154 vsyscall_clock = VVIRT(.vsyscall_clock); 155 156 157 .vsyscall_1 ADDR(.vsyscall_0) + 1024: AT(VLOAD(.vsyscall_1)) { 158 *(.vsyscall_1) 159 } 160 .vsyscall_2 ADDR(.vsyscall_0) + 2048: AT(VLOAD(.vsyscall_2)) { 161 *(.vsyscall_2) 162 } 163 164 .vgetcpu_mode : AT(VLOAD(.vgetcpu_mode)) { 165 *(.vgetcpu_mode) 166 } 167 vgetcpu_mode = VVIRT(.vgetcpu_mode); 168 169 . = ALIGN(CONFIG_X86_L1_CACHE_BYTES); 170 .jiffies : AT(VLOAD(.jiffies)) { 171 *(.jiffies) 172 } 173 jiffies = VVIRT(.jiffies); 174 175 .vsyscall_3 ADDR(.vsyscall_0) + 3072: AT(VLOAD(.vsyscall_3)) { 176 *(.vsyscall_3) 177 } 178 179 . = __vsyscall_0 + PAGE_SIZE; 180 181#undef VSYSCALL_ADDR 182#undef VLOAD_OFFSET 183#undef VLOAD 184#undef VVIRT_OFFSET 185#undef VVIRT 186 187#endif /* CONFIG_X86_64 */ 188 189 /* Init code and data - will be freed after init */ 190 . = ALIGN(PAGE_SIZE); 191 .init.begin : AT(ADDR(.init.begin) - LOAD_OFFSET) { 192 __init_begin = .; /* paired with __init_end */ 193 } 194 195#if defined(CONFIG_X86_64) && defined(CONFIG_SMP) 196 /* 197 * percpu offsets are zero-based on SMP. PERCPU_VADDR() changes the 198 * output PHDR, so the next output section - .init.text - should 199 * start another segment - init. 200 */ 201 PERCPU_VADDR(0, :percpu) 202#endif 203 204 INIT_TEXT_SECTION(PAGE_SIZE) 205#ifdef CONFIG_X86_64 206 :init 207#endif 208 209 INIT_DATA_SECTION(16) 210 211 .x86_cpu_dev.init : AT(ADDR(.x86_cpu_dev.init) - LOAD_OFFSET) { 212 __x86_cpu_dev_start = .; 213 *(.x86_cpu_dev.init) 214 __x86_cpu_dev_end = .; 215 } 216 217 . = ALIGN(8); 218 .parainstructions : AT(ADDR(.parainstructions) - LOAD_OFFSET) { 219 __parainstructions = .; 220 *(.parainstructions) 221 __parainstructions_end = .; 222 } 223 224 . = ALIGN(8); 225 .altinstructions : AT(ADDR(.altinstructions) - LOAD_OFFSET) { 226 __alt_instructions = .; 227 *(.altinstructions) 228 __alt_instructions_end = .; 229 } 230 231 .altinstr_replacement : AT(ADDR(.altinstr_replacement) - LOAD_OFFSET) { 232 *(.altinstr_replacement) 233 } 234 235 /* 236 * .exit.text is discard at runtime, not link time, to deal with 237 * references from .altinstructions and .eh_frame 238 */ 239 .exit.text : AT(ADDR(.exit.text) - LOAD_OFFSET) { 240 EXIT_TEXT 241 } 242 243 .exit.data : AT(ADDR(.exit.data) - LOAD_OFFSET) { 244 EXIT_DATA 245 } 246 247#if !defined(CONFIG_X86_64) || !defined(CONFIG_SMP) 248 PERCPU(PAGE_SIZE) 249#endif 250 251 . = ALIGN(PAGE_SIZE); 252 253 /* freed after init ends here */ 254 .init.end : AT(ADDR(.init.end) - LOAD_OFFSET) { 255 __init_end = .; 256 } 257 258 /* 259 * smp_locks might be freed after init 260 * start/end must be page aligned 261 */ 262 . = ALIGN(PAGE_SIZE); 263 .smp_locks : AT(ADDR(.smp_locks) - LOAD_OFFSET) { 264 __smp_locks = .; 265 *(.smp_locks) 266 __smp_locks_end = .; 267 . = ALIGN(PAGE_SIZE); 268 } 269 270#ifdef CONFIG_X86_64 271 .data_nosave : AT(ADDR(.data_nosave) - LOAD_OFFSET) { 272 NOSAVE_DATA 273 } 274#endif 275 276 /* BSS */ 277 . = ALIGN(PAGE_SIZE); 278 .bss : AT(ADDR(.bss) - LOAD_OFFSET) { 279 __bss_start = .; 280 *(.bss.page_aligned) 281 *(.bss) 282 . = ALIGN(4); 283 __bss_stop = .; 284 } 285 286 . = ALIGN(PAGE_SIZE); 287 .brk : AT(ADDR(.brk) - LOAD_OFFSET) { 288 __brk_base = .; 289 . += 64 * 1024; /* 64k alignment slop space */ 290 *(.brk_reservation) /* areas brk users have reserved */ 291 __brk_limit = .; 292 } 293 294 .end : AT(ADDR(.end) - LOAD_OFFSET) { 295 _end = .; 296 } 297 298 STABS_DEBUG 299 DWARF_DEBUG 300 301 /* Sections to be discarded */ 302 DISCARDS 303 /DISCARD/ : { *(.eh_frame) } 304} 305 306 307#ifdef CONFIG_X86_32 308. = ASSERT((_end - LOAD_OFFSET <= KERNEL_IMAGE_SIZE), 309 "kernel image bigger than KERNEL_IMAGE_SIZE"); 310#else 311/* 312 * Per-cpu symbols which need to be offset from __per_cpu_load 313 * for the boot processor. 314 */ 315#define INIT_PER_CPU(x) init_per_cpu__##x = per_cpu__##x + __per_cpu_load 316INIT_PER_CPU(gdt_page); 317INIT_PER_CPU(irq_stack_union); 318 319/* 320 * Build-time check on the image size: 321 */ 322. = ASSERT((_end - _text <= KERNEL_IMAGE_SIZE), 323 "kernel image bigger than KERNEL_IMAGE_SIZE"); 324 325#ifdef CONFIG_SMP 326. = ASSERT((per_cpu__irq_stack_union == 0), 327 "irq_stack_union is not at start of per-cpu area"); 328#endif 329 330#endif /* CONFIG_X86_32 */ 331 332#ifdef CONFIG_KEXEC 333#include <asm/kexec.h> 334 335. = ASSERT(kexec_control_code_size <= KEXEC_CONTROL_CODE_MAX_SIZE, 336 "kexec control code size is too big"); 337#endif 338 339