1 /* 2 * Helper macros to support writing architecture specific 3 * linker scripts. 4 * 5 * A minimal linker scripts has following content: 6 * [This is a sample, architectures may have special requiriements] 7 * 8 * OUTPUT_FORMAT(...) 9 * OUTPUT_ARCH(...) 10 * ENTRY(...) 11 * SECTIONS 12 * { 13 * . = START; 14 * __init_begin = .; 15 * HEAD_TEXT_SECTION 16 * INIT_TEXT_SECTION(PAGE_SIZE) 17 * INIT_DATA_SECTION(...) 18 * PERCPU_SECTION(CACHELINE_SIZE) 19 * __init_end = .; 20 * 21 * _stext = .; 22 * TEXT_SECTION = 0 23 * _etext = .; 24 * 25 * _sdata = .; 26 * RO_DATA(PAGE_SIZE) 27 * RW_DATA(...) 28 * _edata = .; 29 * 30 * EXCEPTION_TABLE(...) 31 * 32 * BSS_SECTION(0, 0, 0) 33 * _end = .; 34 * 35 * STABS_DEBUG 36 * DWARF_DEBUG 37 * ELF_DETAILS 38 * 39 * DISCARDS // must be the last 40 * } 41 * 42 * [__init_begin, __init_end] is the init section that may be freed after init 43 * // __init_begin and __init_end should be page aligned, so that we can 44 * // free the whole .init memory 45 * [_stext, _etext] is the text section 46 * [_sdata, _edata] is the data section 47 * 48 * Some of the included output section have their own set of constants. 49 * Examples are: [__initramfs_start, __initramfs_end] for initramfs and 50 * [__nosave_begin, __nosave_end] for the nosave data 51 */ 52 53 #ifndef LOAD_OFFSET 54 #define LOAD_OFFSET 0 55 #endif 56 57 /* 58 * Only some architectures want to have the .notes segment visible in 59 * a separate PT_NOTE ELF Program Header. When this happens, it needs 60 * to be visible in both the kernel text's PT_LOAD and the PT_NOTE 61 * Program Headers. In this case, though, the PT_LOAD needs to be made 62 * the default again so that all the following sections don't also end 63 * up in the PT_NOTE Program Header. 64 */ 65 #ifdef EMITS_PT_NOTE 66 #define NOTES_HEADERS :text :note 67 #define NOTES_HEADERS_RESTORE __restore_ph : { *(.__restore_ph) } :text 68 #else 69 #define NOTES_HEADERS 70 #define NOTES_HEADERS_RESTORE 71 #endif 72 73 /* 74 * Some architectures have non-executable read-only exception tables. 75 * They can be added to the RO_DATA segment by specifying their desired 76 * alignment. 77 */ 78 #ifdef RO_EXCEPTION_TABLE_ALIGN 79 #define RO_EXCEPTION_TABLE EXCEPTION_TABLE(RO_EXCEPTION_TABLE_ALIGN) 80 #else 81 #define RO_EXCEPTION_TABLE 82 #endif 83 84 /* Align . to a 8 byte boundary equals to maximum function alignment. */ 85 #define ALIGN_FUNCTION() . = ALIGN(8) 86 87 /* 88 * LD_DEAD_CODE_DATA_ELIMINATION option enables -fdata-sections, which 89 * generates .data.identifier sections, which need to be pulled in with 90 * .data. We don't want to pull in .data..other sections, which Linux 91 * has defined. Same for text and bss. 92 * 93 * RODATA_MAIN is not used because existing code already defines .rodata.x 94 * sections to be brought in with rodata. 95 */ 96 #ifdef CONFIG_LD_DEAD_CODE_DATA_ELIMINATION 97 #define TEXT_MAIN .text .text.[0-9a-zA-Z_]* 98 #define DATA_MAIN .data .data.[0-9a-zA-Z_]* .data..LPBX* 99 #define SDATA_MAIN .sdata .sdata.[0-9a-zA-Z_]* 100 #define RODATA_MAIN .rodata .rodata.[0-9a-zA-Z_]* 101 #define BSS_MAIN .bss .bss.[0-9a-zA-Z_]* 102 #define SBSS_MAIN .sbss .sbss.[0-9a-zA-Z_]* 103 #else 104 #define TEXT_MAIN .text 105 #define DATA_MAIN .data 106 #define SDATA_MAIN .sdata 107 #define RODATA_MAIN .rodata 108 #define BSS_MAIN .bss 109 #define SBSS_MAIN .sbss 110 #endif 111 112 /* 113 * GCC 4.5 and later have a 32 bytes section alignment for structures. 114 * Except GCC 4.9, that feels the need to align on 64 bytes. 115 */ 116 #if __GNUC__ == 4 && __GNUC_MINOR__ == 9 117 #define STRUCT_ALIGNMENT 64 118 #else 119 #define STRUCT_ALIGNMENT 32 120 #endif 121 #define STRUCT_ALIGN() . = ALIGN(STRUCT_ALIGNMENT) 122 123 /* 124 * The order of the sched class addresses are important, as they are 125 * used to determine the order of the priority of each sched class in 126 * relation to each other. 127 */ 128 #define SCHED_DATA \ 129 STRUCT_ALIGN(); \ 130 __begin_sched_classes = .; \ 131 *(__idle_sched_class) \ 132 *(__fair_sched_class) \ 133 *(__rt_sched_class) \ 134 *(__dl_sched_class) \ 135 *(__stop_sched_class) \ 136 __end_sched_classes = .; 137 138 /* The actual configuration determine if the init/exit sections 139 * are handled as text/data or they can be discarded (which 140 * often happens at runtime) 141 */ 142 #ifdef CONFIG_HOTPLUG_CPU 143 #define CPU_KEEP(sec) *(.cpu##sec) 144 #define CPU_DISCARD(sec) 145 #else 146 #define CPU_KEEP(sec) 147 #define CPU_DISCARD(sec) *(.cpu##sec) 148 #endif 149 150 #if defined(CONFIG_MEMORY_HOTPLUG) 151 #define MEM_KEEP(sec) *(.mem##sec) 152 #define MEM_DISCARD(sec) 153 #else 154 #define MEM_KEEP(sec) 155 #define MEM_DISCARD(sec) *(.mem##sec) 156 #endif 157 158 #ifdef CONFIG_FTRACE_MCOUNT_RECORD 159 /* 160 * The ftrace call sites are logged to a section whose name depends on the 161 * compiler option used. A given kernel image will only use one, AKA 162 * FTRACE_CALLSITE_SECTION. We capture all of them here to avoid header 163 * dependencies for FTRACE_CALLSITE_SECTION's definition. 164 * 165 * Need to also make ftrace_stub_graph point to ftrace_stub 166 * so that the same stub location may have different protocols 167 * and not mess up with C verifiers. 168 */ 169 #define MCOUNT_REC() . = ALIGN(8); \ 170 __start_mcount_loc = .; \ 171 KEEP(*(__mcount_loc)) \ 172 KEEP(*(__patchable_function_entries)) \ 173 __stop_mcount_loc = .; \ 174 ftrace_stub_graph = ftrace_stub; 175 #else 176 # ifdef CONFIG_FUNCTION_TRACER 177 # define MCOUNT_REC() ftrace_stub_graph = ftrace_stub; 178 # else 179 # define MCOUNT_REC() 180 # endif 181 #endif 182 183 #ifdef CONFIG_TRACE_BRANCH_PROFILING 184 #define LIKELY_PROFILE() __start_annotated_branch_profile = .; \ 185 KEEP(*(_ftrace_annotated_branch)) \ 186 __stop_annotated_branch_profile = .; 187 #else 188 #define LIKELY_PROFILE() 189 #endif 190 191 #ifdef CONFIG_PROFILE_ALL_BRANCHES 192 #define BRANCH_PROFILE() __start_branch_profile = .; \ 193 KEEP(*(_ftrace_branch)) \ 194 __stop_branch_profile = .; 195 #else 196 #define BRANCH_PROFILE() 197 #endif 198 199 #ifdef CONFIG_KPROBES 200 #define KPROBE_BLACKLIST() . = ALIGN(8); \ 201 __start_kprobe_blacklist = .; \ 202 KEEP(*(_kprobe_blacklist)) \ 203 __stop_kprobe_blacklist = .; 204 #else 205 #define KPROBE_BLACKLIST() 206 #endif 207 208 #ifdef CONFIG_FUNCTION_ERROR_INJECTION 209 #define ERROR_INJECT_WHITELIST() STRUCT_ALIGN(); \ 210 __start_error_injection_whitelist = .; \ 211 KEEP(*(_error_injection_whitelist)) \ 212 __stop_error_injection_whitelist = .; 213 #else 214 #define ERROR_INJECT_WHITELIST() 215 #endif 216 217 #ifdef CONFIG_EVENT_TRACING 218 #define FTRACE_EVENTS() . = ALIGN(8); \ 219 __start_ftrace_events = .; \ 220 KEEP(*(_ftrace_events)) \ 221 __stop_ftrace_events = .; \ 222 __start_ftrace_eval_maps = .; \ 223 KEEP(*(_ftrace_eval_map)) \ 224 __stop_ftrace_eval_maps = .; 225 #else 226 #define FTRACE_EVENTS() 227 #endif 228 229 #ifdef CONFIG_TRACING 230 #define TRACE_PRINTKS() __start___trace_bprintk_fmt = .; \ 231 KEEP(*(__trace_printk_fmt)) /* Trace_printk fmt' pointer */ \ 232 __stop___trace_bprintk_fmt = .; 233 #define TRACEPOINT_STR() __start___tracepoint_str = .; \ 234 KEEP(*(__tracepoint_str)) /* Trace_printk fmt' pointer */ \ 235 __stop___tracepoint_str = .; 236 #else 237 #define TRACE_PRINTKS() 238 #define TRACEPOINT_STR() 239 #endif 240 241 #ifdef CONFIG_FTRACE_SYSCALLS 242 #define TRACE_SYSCALLS() . = ALIGN(8); \ 243 __start_syscalls_metadata = .; \ 244 KEEP(*(__syscalls_metadata)) \ 245 __stop_syscalls_metadata = .; 246 #else 247 #define TRACE_SYSCALLS() 248 #endif 249 250 #ifdef CONFIG_BPF_EVENTS 251 #define BPF_RAW_TP() STRUCT_ALIGN(); \ 252 __start__bpf_raw_tp = .; \ 253 KEEP(*(__bpf_raw_tp_map)) \ 254 __stop__bpf_raw_tp = .; 255 #else 256 #define BPF_RAW_TP() 257 #endif 258 259 #ifdef CONFIG_SERIAL_EARLYCON 260 #define EARLYCON_TABLE() . = ALIGN(8); \ 261 __earlycon_table = .; \ 262 KEEP(*(__earlycon_table)) \ 263 __earlycon_table_end = .; 264 #else 265 #define EARLYCON_TABLE() 266 #endif 267 268 #ifdef CONFIG_SECURITY 269 #define LSM_TABLE() . = ALIGN(8); \ 270 __start_lsm_info = .; \ 271 KEEP(*(.lsm_info.init)) \ 272 __end_lsm_info = .; 273 #define EARLY_LSM_TABLE() . = ALIGN(8); \ 274 __start_early_lsm_info = .; \ 275 KEEP(*(.early_lsm_info.init)) \ 276 __end_early_lsm_info = .; 277 #else 278 #define LSM_TABLE() 279 #define EARLY_LSM_TABLE() 280 #endif 281 282 #define ___OF_TABLE(cfg, name) _OF_TABLE_##cfg(name) 283 #define __OF_TABLE(cfg, name) ___OF_TABLE(cfg, name) 284 #define OF_TABLE(cfg, name) __OF_TABLE(IS_ENABLED(cfg), name) 285 #define _OF_TABLE_0(name) 286 #define _OF_TABLE_1(name) \ 287 . = ALIGN(8); \ 288 __##name##_of_table = .; \ 289 KEEP(*(__##name##_of_table)) \ 290 KEEP(*(__##name##_of_table_end)) 291 292 #define TIMER_OF_TABLES() OF_TABLE(CONFIG_TIMER_OF, timer) 293 #define IRQCHIP_OF_MATCH_TABLE() OF_TABLE(CONFIG_IRQCHIP, irqchip) 294 #define CLK_OF_TABLES() OF_TABLE(CONFIG_COMMON_CLK, clk) 295 #define RESERVEDMEM_OF_TABLES() OF_TABLE(CONFIG_OF_RESERVED_MEM, reservedmem) 296 #define CPU_METHOD_OF_TABLES() OF_TABLE(CONFIG_SMP, cpu_method) 297 #define CPUIDLE_METHOD_OF_TABLES() OF_TABLE(CONFIG_CPU_IDLE, cpuidle_method) 298 299 #ifdef CONFIG_ACPI 300 #define ACPI_PROBE_TABLE(name) \ 301 . = ALIGN(8); \ 302 __##name##_acpi_probe_table = .; \ 303 KEEP(*(__##name##_acpi_probe_table)) \ 304 __##name##_acpi_probe_table_end = .; 305 #else 306 #define ACPI_PROBE_TABLE(name) 307 #endif 308 309 #ifdef CONFIG_THERMAL 310 #define THERMAL_TABLE(name) \ 311 . = ALIGN(8); \ 312 __##name##_thermal_table = .; \ 313 KEEP(*(__##name##_thermal_table)) \ 314 __##name##_thermal_table_end = .; 315 #else 316 #define THERMAL_TABLE(name) 317 #endif 318 319 #define KERNEL_DTB() \ 320 STRUCT_ALIGN(); \ 321 __dtb_start = .; \ 322 KEEP(*(.dtb.init.rodata)) \ 323 __dtb_end = .; 324 325 /* 326 * .data section 327 */ 328 #define DATA_DATA \ 329 *(.xiptext) \ 330 *(DATA_MAIN) \ 331 *(.ref.data) \ 332 *(.data..shared_aligned) /* percpu related */ \ 333 MEM_KEEP(init.data*) \ 334 MEM_KEEP(exit.data*) \ 335 *(.data.unlikely) \ 336 __start_once = .; \ 337 *(.data.once) \ 338 __end_once = .; \ 339 STRUCT_ALIGN(); \ 340 *(__tracepoints) \ 341 /* implement dynamic printk debug */ \ 342 . = ALIGN(8); \ 343 __start___dyndbg = .; \ 344 KEEP(*(__dyndbg)) \ 345 __stop___dyndbg = .; \ 346 LIKELY_PROFILE() \ 347 BRANCH_PROFILE() \ 348 TRACE_PRINTKS() \ 349 BPF_RAW_TP() \ 350 TRACEPOINT_STR() 351 352 /* 353 * Data section helpers 354 */ 355 #define NOSAVE_DATA \ 356 . = ALIGN(PAGE_SIZE); \ 357 __nosave_begin = .; \ 358 *(.data..nosave) \ 359 . = ALIGN(PAGE_SIZE); \ 360 __nosave_end = .; 361 362 #define PAGE_ALIGNED_DATA(page_align) \ 363 . = ALIGN(page_align); \ 364 *(.data..page_aligned) \ 365 . = ALIGN(page_align); 366 367 #define READ_MOSTLY_DATA(align) \ 368 . = ALIGN(align); \ 369 *(.data..read_mostly) \ 370 . = ALIGN(align); 371 372 #define CACHELINE_ALIGNED_DATA(align) \ 373 . = ALIGN(align); \ 374 *(.data..cacheline_aligned) 375 376 #define INIT_TASK_DATA(align) \ 377 . = ALIGN(align); \ 378 __start_init_task = .; \ 379 init_thread_union = .; \ 380 init_stack = .; \ 381 KEEP(*(.data..init_task)) \ 382 KEEP(*(.data..init_thread_info)) \ 383 . = __start_init_task + THREAD_SIZE; \ 384 __end_init_task = .; 385 386 #define JUMP_TABLE_DATA \ 387 . = ALIGN(8); \ 388 __start___jump_table = .; \ 389 KEEP(*(__jump_table)) \ 390 __stop___jump_table = .; 391 392 #define STATIC_CALL_DATA \ 393 . = ALIGN(8); \ 394 __start_static_call_sites = .; \ 395 KEEP(*(.static_call_sites)) \ 396 __stop_static_call_sites = .; \ 397 __start_static_call_tramp_key = .; \ 398 KEEP(*(.static_call_tramp_key)) \ 399 __stop_static_call_tramp_key = .; 400 401 /* 402 * Allow architectures to handle ro_after_init data on their 403 * own by defining an empty RO_AFTER_INIT_DATA. 404 */ 405 #ifndef RO_AFTER_INIT_DATA 406 #define RO_AFTER_INIT_DATA \ 407 . = ALIGN(8); \ 408 __start_ro_after_init = .; \ 409 *(.data..ro_after_init .data.rel.ro.*) \ 410 JUMP_TABLE_DATA \ 411 STATIC_CALL_DATA \ 412 __end_ro_after_init = .; 413 #endif 414 415 /* 416 * Read only Data 417 */ 418 #define RO_DATA(align) \ 419 . = ALIGN((align)); \ 420 .rodata : AT(ADDR(.rodata) - LOAD_OFFSET) { \ 421 __start_rodata = .; \ 422 *(.rodata) *(.rodata.*) \ 423 SCHED_DATA \ 424 RO_AFTER_INIT_DATA /* Read only after init */ \ 425 . = ALIGN(8); \ 426 __start___tracepoints_ptrs = .; \ 427 KEEP(*(__tracepoints_ptrs)) /* Tracepoints: pointer array */ \ 428 __stop___tracepoints_ptrs = .; \ 429 *(__tracepoints_strings)/* Tracepoints: strings */ \ 430 } \ 431 \ 432 .rodata1 : AT(ADDR(.rodata1) - LOAD_OFFSET) { \ 433 *(.rodata1) \ 434 } \ 435 \ 436 /* PCI quirks */ \ 437 .pci_fixup : AT(ADDR(.pci_fixup) - LOAD_OFFSET) { \ 438 __start_pci_fixups_early = .; \ 439 KEEP(*(.pci_fixup_early)) \ 440 __end_pci_fixups_early = .; \ 441 __start_pci_fixups_header = .; \ 442 KEEP(*(.pci_fixup_header)) \ 443 __end_pci_fixups_header = .; \ 444 __start_pci_fixups_final = .; \ 445 KEEP(*(.pci_fixup_final)) \ 446 __end_pci_fixups_final = .; \ 447 __start_pci_fixups_enable = .; \ 448 KEEP(*(.pci_fixup_enable)) \ 449 __end_pci_fixups_enable = .; \ 450 __start_pci_fixups_resume = .; \ 451 KEEP(*(.pci_fixup_resume)) \ 452 __end_pci_fixups_resume = .; \ 453 __start_pci_fixups_resume_early = .; \ 454 KEEP(*(.pci_fixup_resume_early)) \ 455 __end_pci_fixups_resume_early = .; \ 456 __start_pci_fixups_suspend = .; \ 457 KEEP(*(.pci_fixup_suspend)) \ 458 __end_pci_fixups_suspend = .; \ 459 __start_pci_fixups_suspend_late = .; \ 460 KEEP(*(.pci_fixup_suspend_late)) \ 461 __end_pci_fixups_suspend_late = .; \ 462 } \ 463 \ 464 /* Built-in firmware blobs */ \ 465 .builtin_fw : AT(ADDR(.builtin_fw) - LOAD_OFFSET) ALIGN(8) { \ 466 __start_builtin_fw = .; \ 467 KEEP(*(.builtin_fw)) \ 468 __end_builtin_fw = .; \ 469 } \ 470 \ 471 TRACEDATA \ 472 \ 473 /* Kernel symbol table: Normal symbols */ \ 474 __ksymtab : AT(ADDR(__ksymtab) - LOAD_OFFSET) { \ 475 __start___ksymtab = .; \ 476 KEEP(*(SORT(___ksymtab+*))) \ 477 __stop___ksymtab = .; \ 478 } \ 479 \ 480 /* Kernel symbol table: GPL-only symbols */ \ 481 __ksymtab_gpl : AT(ADDR(__ksymtab_gpl) - LOAD_OFFSET) { \ 482 __start___ksymtab_gpl = .; \ 483 KEEP(*(SORT(___ksymtab_gpl+*))) \ 484 __stop___ksymtab_gpl = .; \ 485 } \ 486 \ 487 /* Kernel symbol table: Normal unused symbols */ \ 488 __ksymtab_unused : AT(ADDR(__ksymtab_unused) - LOAD_OFFSET) { \ 489 __start___ksymtab_unused = .; \ 490 KEEP(*(SORT(___ksymtab_unused+*))) \ 491 __stop___ksymtab_unused = .; \ 492 } \ 493 \ 494 /* Kernel symbol table: GPL-only unused symbols */ \ 495 __ksymtab_unused_gpl : AT(ADDR(__ksymtab_unused_gpl) - LOAD_OFFSET) { \ 496 __start___ksymtab_unused_gpl = .; \ 497 KEEP(*(SORT(___ksymtab_unused_gpl+*))) \ 498 __stop___ksymtab_unused_gpl = .; \ 499 } \ 500 \ 501 /* Kernel symbol table: GPL-future-only symbols */ \ 502 __ksymtab_gpl_future : AT(ADDR(__ksymtab_gpl_future) - LOAD_OFFSET) { \ 503 __start___ksymtab_gpl_future = .; \ 504 KEEP(*(SORT(___ksymtab_gpl_future+*))) \ 505 __stop___ksymtab_gpl_future = .; \ 506 } \ 507 \ 508 /* Kernel symbol table: Normal symbols */ \ 509 __kcrctab : AT(ADDR(__kcrctab) - LOAD_OFFSET) { \ 510 __start___kcrctab = .; \ 511 KEEP(*(SORT(___kcrctab+*))) \ 512 __stop___kcrctab = .; \ 513 } \ 514 \ 515 /* Kernel symbol table: GPL-only symbols */ \ 516 __kcrctab_gpl : AT(ADDR(__kcrctab_gpl) - LOAD_OFFSET) { \ 517 __start___kcrctab_gpl = .; \ 518 KEEP(*(SORT(___kcrctab_gpl+*))) \ 519 __stop___kcrctab_gpl = .; \ 520 } \ 521 \ 522 /* Kernel symbol table: Normal unused symbols */ \ 523 __kcrctab_unused : AT(ADDR(__kcrctab_unused) - LOAD_OFFSET) { \ 524 __start___kcrctab_unused = .; \ 525 KEEP(*(SORT(___kcrctab_unused+*))) \ 526 __stop___kcrctab_unused = .; \ 527 } \ 528 \ 529 /* Kernel symbol table: GPL-only unused symbols */ \ 530 __kcrctab_unused_gpl : AT(ADDR(__kcrctab_unused_gpl) - LOAD_OFFSET) { \ 531 __start___kcrctab_unused_gpl = .; \ 532 KEEP(*(SORT(___kcrctab_unused_gpl+*))) \ 533 __stop___kcrctab_unused_gpl = .; \ 534 } \ 535 \ 536 /* Kernel symbol table: GPL-future-only symbols */ \ 537 __kcrctab_gpl_future : AT(ADDR(__kcrctab_gpl_future) - LOAD_OFFSET) { \ 538 __start___kcrctab_gpl_future = .; \ 539 KEEP(*(SORT(___kcrctab_gpl_future+*))) \ 540 __stop___kcrctab_gpl_future = .; \ 541 } \ 542 \ 543 /* Kernel symbol table: strings */ \ 544 __ksymtab_strings : AT(ADDR(__ksymtab_strings) - LOAD_OFFSET) { \ 545 *(__ksymtab_strings) \ 546 } \ 547 \ 548 /* __*init sections */ \ 549 __init_rodata : AT(ADDR(__init_rodata) - LOAD_OFFSET) { \ 550 *(.ref.rodata) \ 551 MEM_KEEP(init.rodata) \ 552 MEM_KEEP(exit.rodata) \ 553 } \ 554 \ 555 /* Built-in module parameters. */ \ 556 __param : AT(ADDR(__param) - LOAD_OFFSET) { \ 557 __start___param = .; \ 558 KEEP(*(__param)) \ 559 __stop___param = .; \ 560 } \ 561 \ 562 /* Built-in module versions. */ \ 563 __modver : AT(ADDR(__modver) - LOAD_OFFSET) { \ 564 __start___modver = .; \ 565 KEEP(*(__modver)) \ 566 __stop___modver = .; \ 567 } \ 568 \ 569 RO_EXCEPTION_TABLE \ 570 NOTES \ 571 BTF \ 572 \ 573 . = ALIGN((align)); \ 574 __end_rodata = .; 575 576 /* 577 * Non-instrumentable text section 578 */ 579 #define NOINSTR_TEXT \ 580 ALIGN_FUNCTION(); \ 581 __noinstr_text_start = .; \ 582 *(.noinstr.text) \ 583 __noinstr_text_end = .; 584 585 /* 586 * .text section. Map to function alignment to avoid address changes 587 * during second ld run in second ld pass when generating System.map 588 * 589 * TEXT_MAIN here will match .text.fixup and .text.unlikely if dead 590 * code elimination is enabled, so these sections should be converted 591 * to use ".." first. 592 */ 593 #define TEXT_TEXT \ 594 ALIGN_FUNCTION(); \ 595 *(.text.hot .text.hot.*) \ 596 *(TEXT_MAIN .text.fixup) \ 597 *(.text.unlikely .text.unlikely.*) \ 598 *(.text.unknown .text.unknown.*) \ 599 NOINSTR_TEXT \ 600 *(.text..refcount) \ 601 *(.ref.text) \ 602 *(.text.asan.* .text.tsan.*) \ 603 MEM_KEEP(init.text*) \ 604 MEM_KEEP(exit.text*) \ 605 606 607 /* sched.text is aling to function alignment to secure we have same 608 * address even at second ld pass when generating System.map */ 609 #define SCHED_TEXT \ 610 ALIGN_FUNCTION(); \ 611 __sched_text_start = .; \ 612 *(.sched.text) \ 613 __sched_text_end = .; 614 615 /* spinlock.text is aling to function alignment to secure we have same 616 * address even at second ld pass when generating System.map */ 617 #define LOCK_TEXT \ 618 ALIGN_FUNCTION(); \ 619 __lock_text_start = .; \ 620 *(.spinlock.text) \ 621 __lock_text_end = .; 622 623 #define CPUIDLE_TEXT \ 624 ALIGN_FUNCTION(); \ 625 __cpuidle_text_start = .; \ 626 *(.cpuidle.text) \ 627 __cpuidle_text_end = .; 628 629 #define KPROBES_TEXT \ 630 ALIGN_FUNCTION(); \ 631 __kprobes_text_start = .; \ 632 *(.kprobes.text) \ 633 __kprobes_text_end = .; 634 635 #define ENTRY_TEXT \ 636 ALIGN_FUNCTION(); \ 637 __entry_text_start = .; \ 638 *(.entry.text) \ 639 __entry_text_end = .; 640 641 #define IRQENTRY_TEXT \ 642 ALIGN_FUNCTION(); \ 643 __irqentry_text_start = .; \ 644 *(.irqentry.text) \ 645 __irqentry_text_end = .; 646 647 #define SOFTIRQENTRY_TEXT \ 648 ALIGN_FUNCTION(); \ 649 __softirqentry_text_start = .; \ 650 *(.softirqentry.text) \ 651 __softirqentry_text_end = .; 652 653 #define STATIC_CALL_TEXT \ 654 ALIGN_FUNCTION(); \ 655 __static_call_text_start = .; \ 656 *(.static_call.text) \ 657 __static_call_text_end = .; 658 659 /* Section used for early init (in .S files) */ 660 #define HEAD_TEXT KEEP(*(.head.text)) 661 662 #define HEAD_TEXT_SECTION \ 663 .head.text : AT(ADDR(.head.text) - LOAD_OFFSET) { \ 664 HEAD_TEXT \ 665 } 666 667 /* 668 * Exception table 669 */ 670 #define EXCEPTION_TABLE(align) \ 671 . = ALIGN(align); \ 672 __ex_table : AT(ADDR(__ex_table) - LOAD_OFFSET) { \ 673 __start___ex_table = .; \ 674 KEEP(*(__ex_table)) \ 675 __stop___ex_table = .; \ 676 } 677 678 /* 679 * .BTF 680 */ 681 #ifdef CONFIG_DEBUG_INFO_BTF 682 #define BTF \ 683 .BTF : AT(ADDR(.BTF) - LOAD_OFFSET) { \ 684 __start_BTF = .; \ 685 KEEP(*(.BTF)) \ 686 __stop_BTF = .; \ 687 } \ 688 . = ALIGN(4); \ 689 .BTF_ids : AT(ADDR(.BTF_ids) - LOAD_OFFSET) { \ 690 *(.BTF_ids) \ 691 } 692 #else 693 #define BTF 694 #endif 695 696 /* 697 * Init task 698 */ 699 #define INIT_TASK_DATA_SECTION(align) \ 700 . = ALIGN(align); \ 701 .data..init_task : AT(ADDR(.data..init_task) - LOAD_OFFSET) { \ 702 INIT_TASK_DATA(align) \ 703 } 704 705 #ifdef CONFIG_CONSTRUCTORS 706 #define KERNEL_CTORS() . = ALIGN(8); \ 707 __ctors_start = .; \ 708 KEEP(*(SORT(.ctors.*))) \ 709 KEEP(*(.ctors)) \ 710 KEEP(*(SORT(.init_array.*))) \ 711 KEEP(*(.init_array)) \ 712 __ctors_end = .; 713 #else 714 #define KERNEL_CTORS() 715 #endif 716 717 /* init and exit section handling */ 718 #define INIT_DATA \ 719 KEEP(*(SORT(___kentry+*))) \ 720 *(.init.data init.data.*) \ 721 MEM_DISCARD(init.data*) \ 722 KERNEL_CTORS() \ 723 MCOUNT_REC() \ 724 *(.init.rodata .init.rodata.*) \ 725 FTRACE_EVENTS() \ 726 TRACE_SYSCALLS() \ 727 KPROBE_BLACKLIST() \ 728 ERROR_INJECT_WHITELIST() \ 729 MEM_DISCARD(init.rodata) \ 730 CLK_OF_TABLES() \ 731 RESERVEDMEM_OF_TABLES() \ 732 TIMER_OF_TABLES() \ 733 CPU_METHOD_OF_TABLES() \ 734 CPUIDLE_METHOD_OF_TABLES() \ 735 KERNEL_DTB() \ 736 IRQCHIP_OF_MATCH_TABLE() \ 737 ACPI_PROBE_TABLE(irqchip) \ 738 ACPI_PROBE_TABLE(timer) \ 739 THERMAL_TABLE(governor) \ 740 EARLYCON_TABLE() \ 741 LSM_TABLE() \ 742 EARLY_LSM_TABLE() \ 743 KUNIT_TABLE() 744 745 #define INIT_TEXT \ 746 *(.init.text .init.text.*) \ 747 *(.text.startup) \ 748 MEM_DISCARD(init.text*) 749 750 #define EXIT_DATA \ 751 *(.exit.data .exit.data.*) \ 752 *(.fini_array .fini_array.*) \ 753 *(.dtors .dtors.*) \ 754 MEM_DISCARD(exit.data*) \ 755 MEM_DISCARD(exit.rodata*) 756 757 #define EXIT_TEXT \ 758 *(.exit.text) \ 759 *(.text.exit) \ 760 MEM_DISCARD(exit.text) 761 762 #define EXIT_CALL \ 763 *(.exitcall.exit) 764 765 /* 766 * bss (Block Started by Symbol) - uninitialized data 767 * zeroed during startup 768 */ 769 #define SBSS(sbss_align) \ 770 . = ALIGN(sbss_align); \ 771 .sbss : AT(ADDR(.sbss) - LOAD_OFFSET) { \ 772 *(.dynsbss) \ 773 *(SBSS_MAIN) \ 774 *(.scommon) \ 775 } 776 777 /* 778 * Allow archectures to redefine BSS_FIRST_SECTIONS to add extra 779 * sections to the front of bss. 780 */ 781 #ifndef BSS_FIRST_SECTIONS 782 #define BSS_FIRST_SECTIONS 783 #endif 784 785 #define BSS(bss_align) \ 786 . = ALIGN(bss_align); \ 787 .bss : AT(ADDR(.bss) - LOAD_OFFSET) { \ 788 BSS_FIRST_SECTIONS \ 789 . = ALIGN(PAGE_SIZE); \ 790 *(.bss..page_aligned) \ 791 . = ALIGN(PAGE_SIZE); \ 792 *(.dynbss) \ 793 *(BSS_MAIN) \ 794 *(COMMON) \ 795 } 796 797 /* 798 * DWARF debug sections. 799 * Symbols in the DWARF debugging sections are relative to 800 * the beginning of the section so we begin them at 0. 801 */ 802 #define DWARF_DEBUG \ 803 /* DWARF 1 */ \ 804 .debug 0 : { *(.debug) } \ 805 .line 0 : { *(.line) } \ 806 /* GNU DWARF 1 extensions */ \ 807 .debug_srcinfo 0 : { *(.debug_srcinfo) } \ 808 .debug_sfnames 0 : { *(.debug_sfnames) } \ 809 /* DWARF 1.1 and DWARF 2 */ \ 810 .debug_aranges 0 : { *(.debug_aranges) } \ 811 .debug_pubnames 0 : { *(.debug_pubnames) } \ 812 /* DWARF 2 */ \ 813 .debug_info 0 : { *(.debug_info \ 814 .gnu.linkonce.wi.*) } \ 815 .debug_abbrev 0 : { *(.debug_abbrev) } \ 816 .debug_line 0 : { *(.debug_line) } \ 817 .debug_frame 0 : { *(.debug_frame) } \ 818 .debug_str 0 : { *(.debug_str) } \ 819 .debug_loc 0 : { *(.debug_loc) } \ 820 .debug_macinfo 0 : { *(.debug_macinfo) } \ 821 .debug_pubtypes 0 : { *(.debug_pubtypes) } \ 822 /* DWARF 3 */ \ 823 .debug_ranges 0 : { *(.debug_ranges) } \ 824 /* SGI/MIPS DWARF 2 extensions */ \ 825 .debug_weaknames 0 : { *(.debug_weaknames) } \ 826 .debug_funcnames 0 : { *(.debug_funcnames) } \ 827 .debug_typenames 0 : { *(.debug_typenames) } \ 828 .debug_varnames 0 : { *(.debug_varnames) } \ 829 /* GNU DWARF 2 extensions */ \ 830 .debug_gnu_pubnames 0 : { *(.debug_gnu_pubnames) } \ 831 .debug_gnu_pubtypes 0 : { *(.debug_gnu_pubtypes) } \ 832 /* DWARF 4 */ \ 833 .debug_types 0 : { *(.debug_types) } \ 834 /* DWARF 5 */ \ 835 .debug_addr 0 : { *(.debug_addr) } \ 836 .debug_line_str 0 : { *(.debug_line_str) } \ 837 .debug_loclists 0 : { *(.debug_loclists) } \ 838 .debug_macro 0 : { *(.debug_macro) } \ 839 .debug_names 0 : { *(.debug_names) } \ 840 .debug_rnglists 0 : { *(.debug_rnglists) } \ 841 .debug_str_offsets 0 : { *(.debug_str_offsets) } 842 843 /* Stabs debugging sections. */ 844 #define STABS_DEBUG \ 845 .stab 0 : { *(.stab) } \ 846 .stabstr 0 : { *(.stabstr) } \ 847 .stab.excl 0 : { *(.stab.excl) } \ 848 .stab.exclstr 0 : { *(.stab.exclstr) } \ 849 .stab.index 0 : { *(.stab.index) } \ 850 .stab.indexstr 0 : { *(.stab.indexstr) } 851 852 /* Required sections not related to debugging. */ 853 #define ELF_DETAILS \ 854 .comment 0 : { *(.comment) } \ 855 .symtab 0 : { *(.symtab) } \ 856 .strtab 0 : { *(.strtab) } \ 857 .shstrtab 0 : { *(.shstrtab) } 858 859 #ifdef CONFIG_GENERIC_BUG 860 #define BUG_TABLE \ 861 . = ALIGN(8); \ 862 __bug_table : AT(ADDR(__bug_table) - LOAD_OFFSET) { \ 863 __start___bug_table = .; \ 864 KEEP(*(__bug_table)) \ 865 __stop___bug_table = .; \ 866 } 867 #else 868 #define BUG_TABLE 869 #endif 870 871 #ifdef CONFIG_UNWINDER_ORC 872 #define ORC_UNWIND_TABLE \ 873 . = ALIGN(4); \ 874 .orc_unwind_ip : AT(ADDR(.orc_unwind_ip) - LOAD_OFFSET) { \ 875 __start_orc_unwind_ip = .; \ 876 KEEP(*(.orc_unwind_ip)) \ 877 __stop_orc_unwind_ip = .; \ 878 } \ 879 . = ALIGN(2); \ 880 .orc_unwind : AT(ADDR(.orc_unwind) - LOAD_OFFSET) { \ 881 __start_orc_unwind = .; \ 882 KEEP(*(.orc_unwind)) \ 883 __stop_orc_unwind = .; \ 884 } \ 885 . = ALIGN(4); \ 886 .orc_lookup : AT(ADDR(.orc_lookup) - LOAD_OFFSET) { \ 887 orc_lookup = .; \ 888 . += (((SIZEOF(.text) + LOOKUP_BLOCK_SIZE - 1) / \ 889 LOOKUP_BLOCK_SIZE) + 1) * 4; \ 890 orc_lookup_end = .; \ 891 } 892 #else 893 #define ORC_UNWIND_TABLE 894 #endif 895 896 #ifdef CONFIG_PM_TRACE 897 #define TRACEDATA \ 898 . = ALIGN(4); \ 899 .tracedata : AT(ADDR(.tracedata) - LOAD_OFFSET) { \ 900 __tracedata_start = .; \ 901 KEEP(*(.tracedata)) \ 902 __tracedata_end = .; \ 903 } 904 #else 905 #define TRACEDATA 906 #endif 907 908 #define NOTES \ 909 .notes : AT(ADDR(.notes) - LOAD_OFFSET) { \ 910 __start_notes = .; \ 911 KEEP(*(.note.*)) \ 912 __stop_notes = .; \ 913 } NOTES_HEADERS \ 914 NOTES_HEADERS_RESTORE 915 916 #define INIT_SETUP(initsetup_align) \ 917 . = ALIGN(initsetup_align); \ 918 __setup_start = .; \ 919 KEEP(*(.init.setup)) \ 920 __setup_end = .; 921 922 #define INIT_CALLS_LEVEL(level) \ 923 __initcall##level##_start = .; \ 924 KEEP(*(.initcall##level##.init)) \ 925 KEEP(*(.initcall##level##s.init)) \ 926 927 #define INIT_CALLS \ 928 __initcall_start = .; \ 929 KEEP(*(.initcallearly.init)) \ 930 INIT_CALLS_LEVEL(0) \ 931 INIT_CALLS_LEVEL(1) \ 932 INIT_CALLS_LEVEL(2) \ 933 INIT_CALLS_LEVEL(3) \ 934 INIT_CALLS_LEVEL(4) \ 935 INIT_CALLS_LEVEL(5) \ 936 INIT_CALLS_LEVEL(rootfs) \ 937 INIT_CALLS_LEVEL(6) \ 938 INIT_CALLS_LEVEL(7) \ 939 __initcall_end = .; 940 941 #define CON_INITCALL \ 942 __con_initcall_start = .; \ 943 KEEP(*(.con_initcall.init)) \ 944 __con_initcall_end = .; 945 946 /* Alignment must be consistent with (kunit_suite *) in include/kunit/test.h */ 947 #define KUNIT_TABLE() \ 948 . = ALIGN(8); \ 949 __kunit_suites_start = .; \ 950 KEEP(*(.kunit_test_suites)) \ 951 __kunit_suites_end = .; 952 953 #ifdef CONFIG_BLK_DEV_INITRD 954 #define INIT_RAM_FS \ 955 . = ALIGN(4); \ 956 __initramfs_start = .; \ 957 KEEP(*(.init.ramfs)) \ 958 . = ALIGN(8); \ 959 KEEP(*(.init.ramfs.info)) 960 #else 961 #define INIT_RAM_FS 962 #endif 963 964 /* 965 * Memory encryption operates on a page basis. Since we need to clear 966 * the memory encryption mask for this section, it needs to be aligned 967 * on a page boundary and be a page-size multiple in length. 968 * 969 * Note: We use a separate section so that only this section gets 970 * decrypted to avoid exposing more than we wish. 971 */ 972 #ifdef CONFIG_AMD_MEM_ENCRYPT 973 #define PERCPU_DECRYPTED_SECTION \ 974 . = ALIGN(PAGE_SIZE); \ 975 *(.data..decrypted) \ 976 *(.data..percpu..decrypted) \ 977 . = ALIGN(PAGE_SIZE); 978 #else 979 #define PERCPU_DECRYPTED_SECTION 980 #endif 981 982 983 /* 984 * Default discarded sections. 985 * 986 * Some archs want to discard exit text/data at runtime rather than 987 * link time due to cross-section references such as alt instructions, 988 * bug table, eh_frame, etc. DISCARDS must be the last of output 989 * section definitions so that such archs put those in earlier section 990 * definitions. 991 */ 992 #ifdef RUNTIME_DISCARD_EXIT 993 #define EXIT_DISCARDS 994 #else 995 #define EXIT_DISCARDS \ 996 EXIT_TEXT \ 997 EXIT_DATA 998 #endif 999 1000 /* 1001 * Clang's -fprofile-arcs, -fsanitize=kernel-address, and 1002 * -fsanitize=thread produce unwanted sections (.eh_frame 1003 * and .init_array.*), but CONFIG_CONSTRUCTORS wants to 1004 * keep any .init_array.* sections. 1005 * https://bugs.llvm.org/show_bug.cgi?id=46478 1006 */ 1007 #if defined(CONFIG_GCOV_KERNEL) || defined(CONFIG_KASAN_GENERIC) || defined(CONFIG_KCSAN) 1008 # ifdef CONFIG_CONSTRUCTORS 1009 # define SANITIZER_DISCARDS \ 1010 *(.eh_frame) 1011 # else 1012 # define SANITIZER_DISCARDS \ 1013 *(.init_array) *(.init_array.*) \ 1014 *(.eh_frame) 1015 # endif 1016 #else 1017 # define SANITIZER_DISCARDS 1018 #endif 1019 1020 #define COMMON_DISCARDS \ 1021 SANITIZER_DISCARDS \ 1022 *(.discard) \ 1023 *(.discard.*) \ 1024 *(.modinfo) \ 1025 /* ld.bfd warns about .gnu.version* even when not emitted */ \ 1026 *(.gnu.version*) \ 1027 1028 #define DISCARDS \ 1029 /DISCARD/ : { \ 1030 EXIT_DISCARDS \ 1031 EXIT_CALL \ 1032 COMMON_DISCARDS \ 1033 } 1034 1035 /** 1036 * PERCPU_INPUT - the percpu input sections 1037 * @cacheline: cacheline size 1038 * 1039 * The core percpu section names and core symbols which do not rely 1040 * directly upon load addresses. 1041 * 1042 * @cacheline is used to align subsections to avoid false cacheline 1043 * sharing between subsections for different purposes. 1044 */ 1045 #define PERCPU_INPUT(cacheline) \ 1046 __per_cpu_start = .; \ 1047 *(.data..percpu..first) \ 1048 . = ALIGN(PAGE_SIZE); \ 1049 *(.data..percpu..page_aligned) \ 1050 . = ALIGN(cacheline); \ 1051 *(.data..percpu..read_mostly) \ 1052 . = ALIGN(cacheline); \ 1053 *(.data..percpu) \ 1054 *(.data..percpu..shared_aligned) \ 1055 PERCPU_DECRYPTED_SECTION \ 1056 __per_cpu_end = .; 1057 1058 /** 1059 * PERCPU_VADDR - define output section for percpu area 1060 * @cacheline: cacheline size 1061 * @vaddr: explicit base address (optional) 1062 * @phdr: destination PHDR (optional) 1063 * 1064 * Macro which expands to output section for percpu area. 1065 * 1066 * @cacheline is used to align subsections to avoid false cacheline 1067 * sharing between subsections for different purposes. 1068 * 1069 * If @vaddr is not blank, it specifies explicit base address and all 1070 * percpu symbols will be offset from the given address. If blank, 1071 * @vaddr always equals @laddr + LOAD_OFFSET. 1072 * 1073 * @phdr defines the output PHDR to use if not blank. Be warned that 1074 * output PHDR is sticky. If @phdr is specified, the next output 1075 * section in the linker script will go there too. @phdr should have 1076 * a leading colon. 1077 * 1078 * Note that this macros defines __per_cpu_load as an absolute symbol. 1079 * If there is no need to put the percpu section at a predetermined 1080 * address, use PERCPU_SECTION. 1081 */ 1082 #define PERCPU_VADDR(cacheline, vaddr, phdr) \ 1083 __per_cpu_load = .; \ 1084 .data..percpu vaddr : AT(__per_cpu_load - LOAD_OFFSET) { \ 1085 PERCPU_INPUT(cacheline) \ 1086 } phdr \ 1087 . = __per_cpu_load + SIZEOF(.data..percpu); 1088 1089 /** 1090 * PERCPU_SECTION - define output section for percpu area, simple version 1091 * @cacheline: cacheline size 1092 * 1093 * Align to PAGE_SIZE and outputs output section for percpu area. This 1094 * macro doesn't manipulate @vaddr or @phdr and __per_cpu_load and 1095 * __per_cpu_start will be identical. 1096 * 1097 * This macro is equivalent to ALIGN(PAGE_SIZE); PERCPU_VADDR(@cacheline,,) 1098 * except that __per_cpu_load is defined as a relative symbol against 1099 * .data..percpu which is required for relocatable x86_32 configuration. 1100 */ 1101 #define PERCPU_SECTION(cacheline) \ 1102 . = ALIGN(PAGE_SIZE); \ 1103 .data..percpu : AT(ADDR(.data..percpu) - LOAD_OFFSET) { \ 1104 __per_cpu_load = .; \ 1105 PERCPU_INPUT(cacheline) \ 1106 } 1107 1108 1109 /* 1110 * Definition of the high level *_SECTION macros 1111 * They will fit only a subset of the architectures 1112 */ 1113 1114 1115 /* 1116 * Writeable data. 1117 * All sections are combined in a single .data section. 1118 * The sections following CONSTRUCTORS are arranged so their 1119 * typical alignment matches. 1120 * A cacheline is typical/always less than a PAGE_SIZE so 1121 * the sections that has this restriction (or similar) 1122 * is located before the ones requiring PAGE_SIZE alignment. 1123 * NOSAVE_DATA starts and ends with a PAGE_SIZE alignment which 1124 * matches the requirement of PAGE_ALIGNED_DATA. 1125 * 1126 * use 0 as page_align if page_aligned data is not used */ 1127 #define RW_DATA(cacheline, pagealigned, inittask) \ 1128 . = ALIGN(PAGE_SIZE); \ 1129 .data : AT(ADDR(.data) - LOAD_OFFSET) { \ 1130 INIT_TASK_DATA(inittask) \ 1131 NOSAVE_DATA \ 1132 PAGE_ALIGNED_DATA(pagealigned) \ 1133 CACHELINE_ALIGNED_DATA(cacheline) \ 1134 READ_MOSTLY_DATA(cacheline) \ 1135 DATA_DATA \ 1136 CONSTRUCTORS \ 1137 } \ 1138 BUG_TABLE \ 1139 1140 #define INIT_TEXT_SECTION(inittext_align) \ 1141 . = ALIGN(inittext_align); \ 1142 .init.text : AT(ADDR(.init.text) - LOAD_OFFSET) { \ 1143 _sinittext = .; \ 1144 INIT_TEXT \ 1145 _einittext = .; \ 1146 } 1147 1148 #define INIT_DATA_SECTION(initsetup_align) \ 1149 .init.data : AT(ADDR(.init.data) - LOAD_OFFSET) { \ 1150 INIT_DATA \ 1151 INIT_SETUP(initsetup_align) \ 1152 INIT_CALLS \ 1153 CON_INITCALL \ 1154 INIT_RAM_FS \ 1155 } 1156 1157 #define BSS_SECTION(sbss_align, bss_align, stop_align) \ 1158 . = ALIGN(sbss_align); \ 1159 __bss_start = .; \ 1160 SBSS(sbss_align) \ 1161 BSS(bss_align) \ 1162 . = ALIGN(stop_align); \ 1163 __bss_stop = .; 1164