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 * With LTO_CLANG, the linker also splits sections by default, so we need 94 * these macros to combine the sections during the final link. 95 * 96 * RODATA_MAIN is not used because existing code already defines .rodata.x 97 * sections to be brought in with rodata. 98 */ 99 #if defined(CONFIG_LD_DEAD_CODE_DATA_ELIMINATION) || defined(CONFIG_LTO_CLANG) 100 #define TEXT_MAIN .text .text.[0-9a-zA-Z_]* 101 #define DATA_MAIN .data .data.[0-9a-zA-Z_]* .data..L* .data..compoundliteral* 102 #define SDATA_MAIN .sdata .sdata.[0-9a-zA-Z_]* 103 #define RODATA_MAIN .rodata .rodata.[0-9a-zA-Z_]* .rodata..L* 104 #define BSS_MAIN .bss .bss.[0-9a-zA-Z_]* .bss..compoundliteral* 105 #define SBSS_MAIN .sbss .sbss.[0-9a-zA-Z_]* 106 #else 107 #define TEXT_MAIN .text 108 #define DATA_MAIN .data 109 #define SDATA_MAIN .sdata 110 #define RODATA_MAIN .rodata 111 #define BSS_MAIN .bss 112 #define SBSS_MAIN .sbss 113 #endif 114 115 /* 116 * GCC 4.5 and later have a 32 bytes section alignment for structures. 117 * Except GCC 4.9, that feels the need to align on 64 bytes. 118 */ 119 #if __GNUC__ == 4 && __GNUC_MINOR__ == 9 120 #define STRUCT_ALIGNMENT 64 121 #else 122 #define STRUCT_ALIGNMENT 32 123 #endif 124 #define STRUCT_ALIGN() . = ALIGN(STRUCT_ALIGNMENT) 125 126 /* 127 * The order of the sched class addresses are important, as they are 128 * used to determine the order of the priority of each sched class in 129 * relation to each other. 130 */ 131 #define SCHED_DATA \ 132 STRUCT_ALIGN(); \ 133 __begin_sched_classes = .; \ 134 *(__idle_sched_class) \ 135 *(__fair_sched_class) \ 136 *(__rt_sched_class) \ 137 *(__dl_sched_class) \ 138 *(__stop_sched_class) \ 139 __end_sched_classes = .; 140 141 /* The actual configuration determine if the init/exit sections 142 * are handled as text/data or they can be discarded (which 143 * often happens at runtime) 144 */ 145 #ifdef CONFIG_HOTPLUG_CPU 146 #define CPU_KEEP(sec) *(.cpu##sec) 147 #define CPU_DISCARD(sec) 148 #else 149 #define CPU_KEEP(sec) 150 #define CPU_DISCARD(sec) *(.cpu##sec) 151 #endif 152 153 #if defined(CONFIG_MEMORY_HOTPLUG) 154 #define MEM_KEEP(sec) *(.mem##sec) 155 #define MEM_DISCARD(sec) 156 #else 157 #define MEM_KEEP(sec) 158 #define MEM_DISCARD(sec) *(.mem##sec) 159 #endif 160 161 #ifdef CONFIG_FTRACE_MCOUNT_RECORD 162 /* 163 * The ftrace call sites are logged to a section whose name depends on the 164 * compiler option used. A given kernel image will only use one, AKA 165 * FTRACE_CALLSITE_SECTION. We capture all of them here to avoid header 166 * dependencies for FTRACE_CALLSITE_SECTION's definition. 167 * 168 * Need to also make ftrace_stub_graph point to ftrace_stub 169 * so that the same stub location may have different protocols 170 * and not mess up with C verifiers. 171 */ 172 #define MCOUNT_REC() . = ALIGN(8); \ 173 __start_mcount_loc = .; \ 174 KEEP(*(__mcount_loc)) \ 175 KEEP(*(__patchable_function_entries)) \ 176 __stop_mcount_loc = .; \ 177 ftrace_stub_graph = ftrace_stub; 178 #else 179 # ifdef CONFIG_FUNCTION_TRACER 180 # define MCOUNT_REC() ftrace_stub_graph = ftrace_stub; 181 # else 182 # define MCOUNT_REC() 183 # endif 184 #endif 185 186 #ifdef CONFIG_TRACE_BRANCH_PROFILING 187 #define LIKELY_PROFILE() __start_annotated_branch_profile = .; \ 188 KEEP(*(_ftrace_annotated_branch)) \ 189 __stop_annotated_branch_profile = .; 190 #else 191 #define LIKELY_PROFILE() 192 #endif 193 194 #ifdef CONFIG_PROFILE_ALL_BRANCHES 195 #define BRANCH_PROFILE() __start_branch_profile = .; \ 196 KEEP(*(_ftrace_branch)) \ 197 __stop_branch_profile = .; 198 #else 199 #define BRANCH_PROFILE() 200 #endif 201 202 #ifdef CONFIG_KPROBES 203 #define KPROBE_BLACKLIST() . = ALIGN(8); \ 204 __start_kprobe_blacklist = .; \ 205 KEEP(*(_kprobe_blacklist)) \ 206 __stop_kprobe_blacklist = .; 207 #else 208 #define KPROBE_BLACKLIST() 209 #endif 210 211 #ifdef CONFIG_FUNCTION_ERROR_INJECTION 212 #define ERROR_INJECT_WHITELIST() STRUCT_ALIGN(); \ 213 __start_error_injection_whitelist = .; \ 214 KEEP(*(_error_injection_whitelist)) \ 215 __stop_error_injection_whitelist = .; 216 #else 217 #define ERROR_INJECT_WHITELIST() 218 #endif 219 220 #ifdef CONFIG_EVENT_TRACING 221 #define FTRACE_EVENTS() . = ALIGN(8); \ 222 __start_ftrace_events = .; \ 223 KEEP(*(_ftrace_events)) \ 224 __stop_ftrace_events = .; \ 225 __start_ftrace_eval_maps = .; \ 226 KEEP(*(_ftrace_eval_map)) \ 227 __stop_ftrace_eval_maps = .; 228 #else 229 #define FTRACE_EVENTS() 230 #endif 231 232 #ifdef CONFIG_TRACING 233 #define TRACE_PRINTKS() __start___trace_bprintk_fmt = .; \ 234 KEEP(*(__trace_printk_fmt)) /* Trace_printk fmt' pointer */ \ 235 __stop___trace_bprintk_fmt = .; 236 #define TRACEPOINT_STR() __start___tracepoint_str = .; \ 237 KEEP(*(__tracepoint_str)) /* Trace_printk fmt' pointer */ \ 238 __stop___tracepoint_str = .; 239 #else 240 #define TRACE_PRINTKS() 241 #define TRACEPOINT_STR() 242 #endif 243 244 #ifdef CONFIG_FTRACE_SYSCALLS 245 #define TRACE_SYSCALLS() . = ALIGN(8); \ 246 __start_syscalls_metadata = .; \ 247 KEEP(*(__syscalls_metadata)) \ 248 __stop_syscalls_metadata = .; 249 #else 250 #define TRACE_SYSCALLS() 251 #endif 252 253 #ifdef CONFIG_BPF_EVENTS 254 #define BPF_RAW_TP() STRUCT_ALIGN(); \ 255 __start__bpf_raw_tp = .; \ 256 KEEP(*(__bpf_raw_tp_map)) \ 257 __stop__bpf_raw_tp = .; 258 #else 259 #define BPF_RAW_TP() 260 #endif 261 262 #ifdef CONFIG_SERIAL_EARLYCON 263 #define EARLYCON_TABLE() . = ALIGN(8); \ 264 __earlycon_table = .; \ 265 KEEP(*(__earlycon_table)) \ 266 __earlycon_table_end = .; 267 #else 268 #define EARLYCON_TABLE() 269 #endif 270 271 #ifdef CONFIG_SECURITY 272 #define LSM_TABLE() . = ALIGN(8); \ 273 __start_lsm_info = .; \ 274 KEEP(*(.lsm_info.init)) \ 275 __end_lsm_info = .; 276 #define EARLY_LSM_TABLE() . = ALIGN(8); \ 277 __start_early_lsm_info = .; \ 278 KEEP(*(.early_lsm_info.init)) \ 279 __end_early_lsm_info = .; 280 #else 281 #define LSM_TABLE() 282 #define EARLY_LSM_TABLE() 283 #endif 284 285 #define ___OF_TABLE(cfg, name) _OF_TABLE_##cfg(name) 286 #define __OF_TABLE(cfg, name) ___OF_TABLE(cfg, name) 287 #define OF_TABLE(cfg, name) __OF_TABLE(IS_ENABLED(cfg), name) 288 #define _OF_TABLE_0(name) 289 #define _OF_TABLE_1(name) \ 290 . = ALIGN(8); \ 291 __##name##_of_table = .; \ 292 KEEP(*(__##name##_of_table)) \ 293 KEEP(*(__##name##_of_table_end)) 294 295 #define TIMER_OF_TABLES() OF_TABLE(CONFIG_TIMER_OF, timer) 296 #define IRQCHIP_OF_MATCH_TABLE() OF_TABLE(CONFIG_IRQCHIP, irqchip) 297 #define CLK_OF_TABLES() OF_TABLE(CONFIG_COMMON_CLK, clk) 298 #define RESERVEDMEM_OF_TABLES() OF_TABLE(CONFIG_OF_RESERVED_MEM, reservedmem) 299 #define CPU_METHOD_OF_TABLES() OF_TABLE(CONFIG_SMP, cpu_method) 300 #define CPUIDLE_METHOD_OF_TABLES() OF_TABLE(CONFIG_CPU_IDLE, cpuidle_method) 301 302 #ifdef CONFIG_ACPI 303 #define ACPI_PROBE_TABLE(name) \ 304 . = ALIGN(8); \ 305 __##name##_acpi_probe_table = .; \ 306 KEEP(*(__##name##_acpi_probe_table)) \ 307 __##name##_acpi_probe_table_end = .; 308 #else 309 #define ACPI_PROBE_TABLE(name) 310 #endif 311 312 #ifdef CONFIG_THERMAL 313 #define THERMAL_TABLE(name) \ 314 . = ALIGN(8); \ 315 __##name##_thermal_table = .; \ 316 KEEP(*(__##name##_thermal_table)) \ 317 __##name##_thermal_table_end = .; 318 #else 319 #define THERMAL_TABLE(name) 320 #endif 321 322 #define KERNEL_DTB() \ 323 STRUCT_ALIGN(); \ 324 __dtb_start = .; \ 325 KEEP(*(.dtb.init.rodata)) \ 326 __dtb_end = .; 327 328 /* 329 * .data section 330 */ 331 #define DATA_DATA \ 332 *(.xiptext) \ 333 *(DATA_MAIN) \ 334 *(.ref.data) \ 335 *(.data..shared_aligned) /* percpu related */ \ 336 MEM_KEEP(init.data*) \ 337 MEM_KEEP(exit.data*) \ 338 *(.data.unlikely) \ 339 __start_once = .; \ 340 *(.data.once) \ 341 __end_once = .; \ 342 STRUCT_ALIGN(); \ 343 *(__tracepoints) \ 344 /* implement dynamic printk debug */ \ 345 . = ALIGN(8); \ 346 __start___dyndbg = .; \ 347 KEEP(*(__dyndbg)) \ 348 __stop___dyndbg = .; \ 349 LIKELY_PROFILE() \ 350 BRANCH_PROFILE() \ 351 TRACE_PRINTKS() \ 352 BPF_RAW_TP() \ 353 TRACEPOINT_STR() 354 355 /* 356 * Data section helpers 357 */ 358 #define NOSAVE_DATA \ 359 . = ALIGN(PAGE_SIZE); \ 360 __nosave_begin = .; \ 361 *(.data..nosave) \ 362 . = ALIGN(PAGE_SIZE); \ 363 __nosave_end = .; 364 365 #define PAGE_ALIGNED_DATA(page_align) \ 366 . = ALIGN(page_align); \ 367 *(.data..page_aligned) \ 368 . = ALIGN(page_align); 369 370 #define READ_MOSTLY_DATA(align) \ 371 . = ALIGN(align); \ 372 *(.data..read_mostly) \ 373 . = ALIGN(align); 374 375 #define CACHELINE_ALIGNED_DATA(align) \ 376 . = ALIGN(align); \ 377 *(.data..cacheline_aligned) 378 379 #define INIT_TASK_DATA(align) \ 380 . = ALIGN(align); \ 381 __start_init_task = .; \ 382 init_thread_union = .; \ 383 init_stack = .; \ 384 KEEP(*(.data..init_task)) \ 385 KEEP(*(.data..init_thread_info)) \ 386 . = __start_init_task + THREAD_SIZE; \ 387 __end_init_task = .; 388 389 #define JUMP_TABLE_DATA \ 390 . = ALIGN(8); \ 391 __start___jump_table = .; \ 392 KEEP(*(__jump_table)) \ 393 __stop___jump_table = .; 394 395 #define STATIC_CALL_DATA \ 396 . = ALIGN(8); \ 397 __start_static_call_sites = .; \ 398 KEEP(*(.static_call_sites)) \ 399 __stop_static_call_sites = .; \ 400 __start_static_call_tramp_key = .; \ 401 KEEP(*(.static_call_tramp_key)) \ 402 __stop_static_call_tramp_key = .; 403 404 /* 405 * Allow architectures to handle ro_after_init data on their 406 * own by defining an empty RO_AFTER_INIT_DATA. 407 */ 408 #ifndef RO_AFTER_INIT_DATA 409 #define RO_AFTER_INIT_DATA \ 410 . = ALIGN(8); \ 411 __start_ro_after_init = .; \ 412 *(.data..ro_after_init .data.rel.ro.*) \ 413 JUMP_TABLE_DATA \ 414 STATIC_CALL_DATA \ 415 __end_ro_after_init = .; 416 #endif 417 418 /* 419 * Read only Data 420 */ 421 #define RO_DATA(align) \ 422 . = ALIGN((align)); \ 423 .rodata : AT(ADDR(.rodata) - LOAD_OFFSET) { \ 424 __start_rodata = .; \ 425 *(.rodata) *(.rodata.*) \ 426 SCHED_DATA \ 427 RO_AFTER_INIT_DATA /* Read only after init */ \ 428 . = ALIGN(8); \ 429 __start___tracepoints_ptrs = .; \ 430 KEEP(*(__tracepoints_ptrs)) /* Tracepoints: pointer array */ \ 431 __stop___tracepoints_ptrs = .; \ 432 *(__tracepoints_strings)/* Tracepoints: strings */ \ 433 } \ 434 \ 435 .rodata1 : AT(ADDR(.rodata1) - LOAD_OFFSET) { \ 436 *(.rodata1) \ 437 } \ 438 \ 439 /* PCI quirks */ \ 440 .pci_fixup : AT(ADDR(.pci_fixup) - LOAD_OFFSET) { \ 441 __start_pci_fixups_early = .; \ 442 KEEP(*(.pci_fixup_early)) \ 443 __end_pci_fixups_early = .; \ 444 __start_pci_fixups_header = .; \ 445 KEEP(*(.pci_fixup_header)) \ 446 __end_pci_fixups_header = .; \ 447 __start_pci_fixups_final = .; \ 448 KEEP(*(.pci_fixup_final)) \ 449 __end_pci_fixups_final = .; \ 450 __start_pci_fixups_enable = .; \ 451 KEEP(*(.pci_fixup_enable)) \ 452 __end_pci_fixups_enable = .; \ 453 __start_pci_fixups_resume = .; \ 454 KEEP(*(.pci_fixup_resume)) \ 455 __end_pci_fixups_resume = .; \ 456 __start_pci_fixups_resume_early = .; \ 457 KEEP(*(.pci_fixup_resume_early)) \ 458 __end_pci_fixups_resume_early = .; \ 459 __start_pci_fixups_suspend = .; \ 460 KEEP(*(.pci_fixup_suspend)) \ 461 __end_pci_fixups_suspend = .; \ 462 __start_pci_fixups_suspend_late = .; \ 463 KEEP(*(.pci_fixup_suspend_late)) \ 464 __end_pci_fixups_suspend_late = .; \ 465 } \ 466 \ 467 /* Built-in firmware blobs */ \ 468 .builtin_fw : AT(ADDR(.builtin_fw) - LOAD_OFFSET) ALIGN(8) { \ 469 __start_builtin_fw = .; \ 470 KEEP(*(.builtin_fw)) \ 471 __end_builtin_fw = .; \ 472 } \ 473 \ 474 TRACEDATA \ 475 \ 476 /* Kernel symbol table: Normal symbols */ \ 477 __ksymtab : AT(ADDR(__ksymtab) - LOAD_OFFSET) { \ 478 __start___ksymtab = .; \ 479 KEEP(*(SORT(___ksymtab+*))) \ 480 __stop___ksymtab = .; \ 481 } \ 482 \ 483 /* Kernel symbol table: GPL-only symbols */ \ 484 __ksymtab_gpl : AT(ADDR(__ksymtab_gpl) - LOAD_OFFSET) { \ 485 __start___ksymtab_gpl = .; \ 486 KEEP(*(SORT(___ksymtab_gpl+*))) \ 487 __stop___ksymtab_gpl = .; \ 488 } \ 489 \ 490 /* Kernel symbol table: Normal unused symbols */ \ 491 __ksymtab_unused : AT(ADDR(__ksymtab_unused) - LOAD_OFFSET) { \ 492 __start___ksymtab_unused = .; \ 493 KEEP(*(SORT(___ksymtab_unused+*))) \ 494 __stop___ksymtab_unused = .; \ 495 } \ 496 \ 497 /* Kernel symbol table: GPL-only unused symbols */ \ 498 __ksymtab_unused_gpl : AT(ADDR(__ksymtab_unused_gpl) - LOAD_OFFSET) { \ 499 __start___ksymtab_unused_gpl = .; \ 500 KEEP(*(SORT(___ksymtab_unused_gpl+*))) \ 501 __stop___ksymtab_unused_gpl = .; \ 502 } \ 503 \ 504 /* Kernel symbol table: GPL-future-only symbols */ \ 505 __ksymtab_gpl_future : AT(ADDR(__ksymtab_gpl_future) - LOAD_OFFSET) { \ 506 __start___ksymtab_gpl_future = .; \ 507 KEEP(*(SORT(___ksymtab_gpl_future+*))) \ 508 __stop___ksymtab_gpl_future = .; \ 509 } \ 510 \ 511 /* Kernel symbol table: Normal symbols */ \ 512 __kcrctab : AT(ADDR(__kcrctab) - LOAD_OFFSET) { \ 513 __start___kcrctab = .; \ 514 KEEP(*(SORT(___kcrctab+*))) \ 515 __stop___kcrctab = .; \ 516 } \ 517 \ 518 /* Kernel symbol table: GPL-only symbols */ \ 519 __kcrctab_gpl : AT(ADDR(__kcrctab_gpl) - LOAD_OFFSET) { \ 520 __start___kcrctab_gpl = .; \ 521 KEEP(*(SORT(___kcrctab_gpl+*))) \ 522 __stop___kcrctab_gpl = .; \ 523 } \ 524 \ 525 /* Kernel symbol table: Normal unused symbols */ \ 526 __kcrctab_unused : AT(ADDR(__kcrctab_unused) - LOAD_OFFSET) { \ 527 __start___kcrctab_unused = .; \ 528 KEEP(*(SORT(___kcrctab_unused+*))) \ 529 __stop___kcrctab_unused = .; \ 530 } \ 531 \ 532 /* Kernel symbol table: GPL-only unused symbols */ \ 533 __kcrctab_unused_gpl : AT(ADDR(__kcrctab_unused_gpl) - LOAD_OFFSET) { \ 534 __start___kcrctab_unused_gpl = .; \ 535 KEEP(*(SORT(___kcrctab_unused_gpl+*))) \ 536 __stop___kcrctab_unused_gpl = .; \ 537 } \ 538 \ 539 /* Kernel symbol table: GPL-future-only symbols */ \ 540 __kcrctab_gpl_future : AT(ADDR(__kcrctab_gpl_future) - LOAD_OFFSET) { \ 541 __start___kcrctab_gpl_future = .; \ 542 KEEP(*(SORT(___kcrctab_gpl_future+*))) \ 543 __stop___kcrctab_gpl_future = .; \ 544 } \ 545 \ 546 /* Kernel symbol table: strings */ \ 547 __ksymtab_strings : AT(ADDR(__ksymtab_strings) - LOAD_OFFSET) { \ 548 *(__ksymtab_strings) \ 549 } \ 550 \ 551 /* __*init sections */ \ 552 __init_rodata : AT(ADDR(__init_rodata) - LOAD_OFFSET) { \ 553 *(.ref.rodata) \ 554 MEM_KEEP(init.rodata) \ 555 MEM_KEEP(exit.rodata) \ 556 } \ 557 \ 558 /* Built-in module parameters. */ \ 559 __param : AT(ADDR(__param) - LOAD_OFFSET) { \ 560 __start___param = .; \ 561 KEEP(*(__param)) \ 562 __stop___param = .; \ 563 } \ 564 \ 565 /* Built-in module versions. */ \ 566 __modver : AT(ADDR(__modver) - LOAD_OFFSET) { \ 567 __start___modver = .; \ 568 KEEP(*(__modver)) \ 569 __stop___modver = .; \ 570 } \ 571 \ 572 RO_EXCEPTION_TABLE \ 573 NOTES \ 574 BTF \ 575 \ 576 . = ALIGN((align)); \ 577 __end_rodata = .; 578 579 580 /* 581 * .text..L.cfi.jumptable.* contain Control-Flow Integrity (CFI) 582 * jump table entries. 583 */ 584 #ifdef CONFIG_CFI_CLANG 585 #define TEXT_CFI_JT \ 586 . = ALIGN(PMD_SIZE); \ 587 __cfi_jt_start = .; \ 588 *(.text..L.cfi.jumptable .text..L.cfi.jumptable.*) \ 589 . = ALIGN(PMD_SIZE); \ 590 __cfi_jt_end = .; 591 #else 592 #define TEXT_CFI_JT 593 #endif 594 595 /* 596 * Non-instrumentable text section 597 */ 598 #define NOINSTR_TEXT \ 599 ALIGN_FUNCTION(); \ 600 __noinstr_text_start = .; \ 601 *(.noinstr.text) \ 602 __noinstr_text_end = .; 603 604 /* 605 * .text section. Map to function alignment to avoid address changes 606 * during second ld run in second ld pass when generating System.map 607 * 608 * TEXT_MAIN here will match .text.fixup and .text.unlikely if dead 609 * code elimination is enabled, so these sections should be converted 610 * to use ".." first. 611 */ 612 #define TEXT_TEXT \ 613 ALIGN_FUNCTION(); \ 614 *(.text.hot .text.hot.*) \ 615 *(TEXT_MAIN .text.fixup) \ 616 *(.text.unlikely .text.unlikely.*) \ 617 *(.text.unknown .text.unknown.*) \ 618 NOINSTR_TEXT \ 619 *(.text..refcount) \ 620 *(.ref.text) \ 621 *(.text.asan.* .text.tsan.*) \ 622 TEXT_CFI_JT \ 623 MEM_KEEP(init.text*) \ 624 MEM_KEEP(exit.text*) \ 625 626 627 /* sched.text is aling to function alignment to secure we have same 628 * address even at second ld pass when generating System.map */ 629 #define SCHED_TEXT \ 630 ALIGN_FUNCTION(); \ 631 __sched_text_start = .; \ 632 *(.sched.text) \ 633 __sched_text_end = .; 634 635 /* spinlock.text is aling to function alignment to secure we have same 636 * address even at second ld pass when generating System.map */ 637 #define LOCK_TEXT \ 638 ALIGN_FUNCTION(); \ 639 __lock_text_start = .; \ 640 *(.spinlock.text) \ 641 __lock_text_end = .; 642 643 #define CPUIDLE_TEXT \ 644 ALIGN_FUNCTION(); \ 645 __cpuidle_text_start = .; \ 646 *(.cpuidle.text) \ 647 __cpuidle_text_end = .; 648 649 #define KPROBES_TEXT \ 650 ALIGN_FUNCTION(); \ 651 __kprobes_text_start = .; \ 652 *(.kprobes.text) \ 653 __kprobes_text_end = .; 654 655 #define ENTRY_TEXT \ 656 ALIGN_FUNCTION(); \ 657 __entry_text_start = .; \ 658 *(.entry.text) \ 659 __entry_text_end = .; 660 661 #define IRQENTRY_TEXT \ 662 ALIGN_FUNCTION(); \ 663 __irqentry_text_start = .; \ 664 *(.irqentry.text) \ 665 __irqentry_text_end = .; 666 667 #define SOFTIRQENTRY_TEXT \ 668 ALIGN_FUNCTION(); \ 669 __softirqentry_text_start = .; \ 670 *(.softirqentry.text) \ 671 __softirqentry_text_end = .; 672 673 #define STATIC_CALL_TEXT \ 674 ALIGN_FUNCTION(); \ 675 __static_call_text_start = .; \ 676 *(.static_call.text) \ 677 __static_call_text_end = .; 678 679 /* Section used for early init (in .S files) */ 680 #define HEAD_TEXT KEEP(*(.head.text)) 681 682 #define HEAD_TEXT_SECTION \ 683 .head.text : AT(ADDR(.head.text) - LOAD_OFFSET) { \ 684 HEAD_TEXT \ 685 } 686 687 /* 688 * Exception table 689 */ 690 #define EXCEPTION_TABLE(align) \ 691 . = ALIGN(align); \ 692 __ex_table : AT(ADDR(__ex_table) - LOAD_OFFSET) { \ 693 __start___ex_table = .; \ 694 KEEP(*(__ex_table)) \ 695 __stop___ex_table = .; \ 696 } 697 698 /* 699 * .BTF 700 */ 701 #ifdef CONFIG_DEBUG_INFO_BTF 702 #define BTF \ 703 .BTF : AT(ADDR(.BTF) - LOAD_OFFSET) { \ 704 __start_BTF = .; \ 705 KEEP(*(.BTF)) \ 706 __stop_BTF = .; \ 707 } \ 708 . = ALIGN(4); \ 709 .BTF_ids : AT(ADDR(.BTF_ids) - LOAD_OFFSET) { \ 710 *(.BTF_ids) \ 711 } 712 #else 713 #define BTF 714 #endif 715 716 /* 717 * Init task 718 */ 719 #define INIT_TASK_DATA_SECTION(align) \ 720 . = ALIGN(align); \ 721 .data..init_task : AT(ADDR(.data..init_task) - LOAD_OFFSET) { \ 722 INIT_TASK_DATA(align) \ 723 } 724 725 #ifdef CONFIG_CONSTRUCTORS 726 #define KERNEL_CTORS() . = ALIGN(8); \ 727 __ctors_start = .; \ 728 KEEP(*(SORT(.ctors.*))) \ 729 KEEP(*(.ctors)) \ 730 KEEP(*(SORT(.init_array.*))) \ 731 KEEP(*(.init_array)) \ 732 __ctors_end = .; 733 #else 734 #define KERNEL_CTORS() 735 #endif 736 737 /* init and exit section handling */ 738 #define INIT_DATA \ 739 KEEP(*(SORT(___kentry+*))) \ 740 *(.init.data init.data.*) \ 741 MEM_DISCARD(init.data*) \ 742 KERNEL_CTORS() \ 743 MCOUNT_REC() \ 744 *(.init.rodata .init.rodata.*) \ 745 FTRACE_EVENTS() \ 746 TRACE_SYSCALLS() \ 747 KPROBE_BLACKLIST() \ 748 ERROR_INJECT_WHITELIST() \ 749 MEM_DISCARD(init.rodata) \ 750 CLK_OF_TABLES() \ 751 RESERVEDMEM_OF_TABLES() \ 752 TIMER_OF_TABLES() \ 753 CPU_METHOD_OF_TABLES() \ 754 CPUIDLE_METHOD_OF_TABLES() \ 755 KERNEL_DTB() \ 756 IRQCHIP_OF_MATCH_TABLE() \ 757 ACPI_PROBE_TABLE(irqchip) \ 758 ACPI_PROBE_TABLE(timer) \ 759 THERMAL_TABLE(governor) \ 760 EARLYCON_TABLE() \ 761 LSM_TABLE() \ 762 EARLY_LSM_TABLE() \ 763 KUNIT_TABLE() 764 765 #define INIT_TEXT \ 766 *(.init.text .init.text.*) \ 767 *(.text.startup) \ 768 MEM_DISCARD(init.text*) 769 770 #define EXIT_DATA \ 771 *(.exit.data .exit.data.*) \ 772 *(.fini_array .fini_array.*) \ 773 *(.dtors .dtors.*) \ 774 MEM_DISCARD(exit.data*) \ 775 MEM_DISCARD(exit.rodata*) 776 777 #define EXIT_TEXT \ 778 *(.exit.text) \ 779 *(.text.exit) \ 780 MEM_DISCARD(exit.text) 781 782 #define EXIT_CALL \ 783 *(.exitcall.exit) 784 785 /* 786 * bss (Block Started by Symbol) - uninitialized data 787 * zeroed during startup 788 */ 789 #define SBSS(sbss_align) \ 790 . = ALIGN(sbss_align); \ 791 .sbss : AT(ADDR(.sbss) - LOAD_OFFSET) { \ 792 *(.dynsbss) \ 793 *(SBSS_MAIN) \ 794 *(.scommon) \ 795 } 796 797 /* 798 * Allow archectures to redefine BSS_FIRST_SECTIONS to add extra 799 * sections to the front of bss. 800 */ 801 #ifndef BSS_FIRST_SECTIONS 802 #define BSS_FIRST_SECTIONS 803 #endif 804 805 #define BSS(bss_align) \ 806 . = ALIGN(bss_align); \ 807 .bss : AT(ADDR(.bss) - LOAD_OFFSET) { \ 808 BSS_FIRST_SECTIONS \ 809 . = ALIGN(PAGE_SIZE); \ 810 *(.bss..page_aligned) \ 811 . = ALIGN(PAGE_SIZE); \ 812 *(.dynbss) \ 813 *(BSS_MAIN) \ 814 *(COMMON) \ 815 } 816 817 /* 818 * DWARF debug sections. 819 * Symbols in the DWARF debugging sections are relative to 820 * the beginning of the section so we begin them at 0. 821 */ 822 #define DWARF_DEBUG \ 823 /* DWARF 1 */ \ 824 .debug 0 : { *(.debug) } \ 825 .line 0 : { *(.line) } \ 826 /* GNU DWARF 1 extensions */ \ 827 .debug_srcinfo 0 : { *(.debug_srcinfo) } \ 828 .debug_sfnames 0 : { *(.debug_sfnames) } \ 829 /* DWARF 1.1 and DWARF 2 */ \ 830 .debug_aranges 0 : { *(.debug_aranges) } \ 831 .debug_pubnames 0 : { *(.debug_pubnames) } \ 832 /* DWARF 2 */ \ 833 .debug_info 0 : { *(.debug_info \ 834 .gnu.linkonce.wi.*) } \ 835 .debug_abbrev 0 : { *(.debug_abbrev) } \ 836 .debug_line 0 : { *(.debug_line) } \ 837 .debug_frame 0 : { *(.debug_frame) } \ 838 .debug_str 0 : { *(.debug_str) } \ 839 .debug_loc 0 : { *(.debug_loc) } \ 840 .debug_macinfo 0 : { *(.debug_macinfo) } \ 841 .debug_pubtypes 0 : { *(.debug_pubtypes) } \ 842 /* DWARF 3 */ \ 843 .debug_ranges 0 : { *(.debug_ranges) } \ 844 /* SGI/MIPS DWARF 2 extensions */ \ 845 .debug_weaknames 0 : { *(.debug_weaknames) } \ 846 .debug_funcnames 0 : { *(.debug_funcnames) } \ 847 .debug_typenames 0 : { *(.debug_typenames) } \ 848 .debug_varnames 0 : { *(.debug_varnames) } \ 849 /* GNU DWARF 2 extensions */ \ 850 .debug_gnu_pubnames 0 : { *(.debug_gnu_pubnames) } \ 851 .debug_gnu_pubtypes 0 : { *(.debug_gnu_pubtypes) } \ 852 /* DWARF 4 */ \ 853 .debug_types 0 : { *(.debug_types) } \ 854 /* DWARF 5 */ \ 855 .debug_addr 0 : { *(.debug_addr) } \ 856 .debug_line_str 0 : { *(.debug_line_str) } \ 857 .debug_loclists 0 : { *(.debug_loclists) } \ 858 .debug_macro 0 : { *(.debug_macro) } \ 859 .debug_names 0 : { *(.debug_names) } \ 860 .debug_rnglists 0 : { *(.debug_rnglists) } \ 861 .debug_str_offsets 0 : { *(.debug_str_offsets) } 862 863 /* Stabs debugging sections. */ 864 #define STABS_DEBUG \ 865 .stab 0 : { *(.stab) } \ 866 .stabstr 0 : { *(.stabstr) } \ 867 .stab.excl 0 : { *(.stab.excl) } \ 868 .stab.exclstr 0 : { *(.stab.exclstr) } \ 869 .stab.index 0 : { *(.stab.index) } \ 870 .stab.indexstr 0 : { *(.stab.indexstr) } 871 872 /* Required sections not related to debugging. */ 873 #define ELF_DETAILS \ 874 .comment 0 : { *(.comment) } \ 875 .symtab 0 : { *(.symtab) } \ 876 .strtab 0 : { *(.strtab) } \ 877 .shstrtab 0 : { *(.shstrtab) } 878 879 #ifdef CONFIG_GENERIC_BUG 880 #define BUG_TABLE \ 881 . = ALIGN(8); \ 882 __bug_table : AT(ADDR(__bug_table) - LOAD_OFFSET) { \ 883 __start___bug_table = .; \ 884 KEEP(*(__bug_table)) \ 885 __stop___bug_table = .; \ 886 } 887 #else 888 #define BUG_TABLE 889 #endif 890 891 #ifdef CONFIG_UNWINDER_ORC 892 #define ORC_UNWIND_TABLE \ 893 . = ALIGN(4); \ 894 .orc_unwind_ip : AT(ADDR(.orc_unwind_ip) - LOAD_OFFSET) { \ 895 __start_orc_unwind_ip = .; \ 896 KEEP(*(.orc_unwind_ip)) \ 897 __stop_orc_unwind_ip = .; \ 898 } \ 899 . = ALIGN(2); \ 900 .orc_unwind : AT(ADDR(.orc_unwind) - LOAD_OFFSET) { \ 901 __start_orc_unwind = .; \ 902 KEEP(*(.orc_unwind)) \ 903 __stop_orc_unwind = .; \ 904 } \ 905 . = ALIGN(4); \ 906 .orc_lookup : AT(ADDR(.orc_lookup) - LOAD_OFFSET) { \ 907 orc_lookup = .; \ 908 . += (((SIZEOF(.text) + LOOKUP_BLOCK_SIZE - 1) / \ 909 LOOKUP_BLOCK_SIZE) + 1) * 4; \ 910 orc_lookup_end = .; \ 911 } 912 #else 913 #define ORC_UNWIND_TABLE 914 #endif 915 916 #ifdef CONFIG_PM_TRACE 917 #define TRACEDATA \ 918 . = ALIGN(4); \ 919 .tracedata : AT(ADDR(.tracedata) - LOAD_OFFSET) { \ 920 __tracedata_start = .; \ 921 KEEP(*(.tracedata)) \ 922 __tracedata_end = .; \ 923 } 924 #else 925 #define TRACEDATA 926 #endif 927 928 #define NOTES \ 929 .notes : AT(ADDR(.notes) - LOAD_OFFSET) { \ 930 __start_notes = .; \ 931 KEEP(*(.note.*)) \ 932 __stop_notes = .; \ 933 } NOTES_HEADERS \ 934 NOTES_HEADERS_RESTORE 935 936 #define INIT_SETUP(initsetup_align) \ 937 . = ALIGN(initsetup_align); \ 938 __setup_start = .; \ 939 KEEP(*(.init.setup)) \ 940 __setup_end = .; 941 942 #define INIT_CALLS_LEVEL(level) \ 943 __initcall##level##_start = .; \ 944 KEEP(*(.initcall##level##.init)) \ 945 KEEP(*(.initcall##level##s.init)) \ 946 947 #define INIT_CALLS \ 948 __initcall_start = .; \ 949 KEEP(*(.initcallearly.init)) \ 950 INIT_CALLS_LEVEL(0) \ 951 INIT_CALLS_LEVEL(1) \ 952 INIT_CALLS_LEVEL(2) \ 953 INIT_CALLS_LEVEL(3) \ 954 INIT_CALLS_LEVEL(4) \ 955 INIT_CALLS_LEVEL(5) \ 956 INIT_CALLS_LEVEL(rootfs) \ 957 INIT_CALLS_LEVEL(6) \ 958 INIT_CALLS_LEVEL(7) \ 959 __initcall_end = .; 960 961 #define CON_INITCALL \ 962 __con_initcall_start = .; \ 963 KEEP(*(.con_initcall.init)) \ 964 __con_initcall_end = .; 965 966 /* Alignment must be consistent with (kunit_suite *) in include/kunit/test.h */ 967 #define KUNIT_TABLE() \ 968 . = ALIGN(8); \ 969 __kunit_suites_start = .; \ 970 KEEP(*(.kunit_test_suites)) \ 971 __kunit_suites_end = .; 972 973 #ifdef CONFIG_BLK_DEV_INITRD 974 #define INIT_RAM_FS \ 975 . = ALIGN(4); \ 976 __initramfs_start = .; \ 977 KEEP(*(.init.ramfs)) \ 978 . = ALIGN(8); \ 979 KEEP(*(.init.ramfs.info)) 980 #else 981 #define INIT_RAM_FS 982 #endif 983 984 /* 985 * Memory encryption operates on a page basis. Since we need to clear 986 * the memory encryption mask for this section, it needs to be aligned 987 * on a page boundary and be a page-size multiple in length. 988 * 989 * Note: We use a separate section so that only this section gets 990 * decrypted to avoid exposing more than we wish. 991 */ 992 #ifdef CONFIG_AMD_MEM_ENCRYPT 993 #define PERCPU_DECRYPTED_SECTION \ 994 . = ALIGN(PAGE_SIZE); \ 995 *(.data..decrypted) \ 996 *(.data..percpu..decrypted) \ 997 . = ALIGN(PAGE_SIZE); 998 #else 999 #define PERCPU_DECRYPTED_SECTION 1000 #endif 1001 1002 1003 /* 1004 * Default discarded sections. 1005 * 1006 * Some archs want to discard exit text/data at runtime rather than 1007 * link time due to cross-section references such as alt instructions, 1008 * bug table, eh_frame, etc. DISCARDS must be the last of output 1009 * section definitions so that such archs put those in earlier section 1010 * definitions. 1011 */ 1012 #ifdef RUNTIME_DISCARD_EXIT 1013 #define EXIT_DISCARDS 1014 #else 1015 #define EXIT_DISCARDS \ 1016 EXIT_TEXT \ 1017 EXIT_DATA 1018 #endif 1019 1020 /* 1021 * Clang's -fprofile-arcs, -fsanitize=kernel-address, and 1022 * -fsanitize=thread produce unwanted sections (.eh_frame 1023 * and .init_array.*), but CONFIG_CONSTRUCTORS wants to 1024 * keep any .init_array.* sections. 1025 * https://bugs.llvm.org/show_bug.cgi?id=46478 1026 */ 1027 #if defined(CONFIG_GCOV_KERNEL) || defined(CONFIG_KASAN_GENERIC) || defined(CONFIG_KCSAN) || \ 1028 defined(CONFIG_CFI_CLANG) 1029 # ifdef CONFIG_CONSTRUCTORS 1030 # define SANITIZER_DISCARDS \ 1031 *(.eh_frame) 1032 # else 1033 # define SANITIZER_DISCARDS \ 1034 *(.init_array) *(.init_array.*) \ 1035 *(.eh_frame) 1036 # endif 1037 #else 1038 # define SANITIZER_DISCARDS 1039 #endif 1040 1041 #define COMMON_DISCARDS \ 1042 SANITIZER_DISCARDS \ 1043 *(.discard) \ 1044 *(.discard.*) \ 1045 *(.modinfo) \ 1046 /* ld.bfd warns about .gnu.version* even when not emitted */ \ 1047 *(.gnu.version*) \ 1048 1049 #define DISCARDS \ 1050 /DISCARD/ : { \ 1051 EXIT_DISCARDS \ 1052 EXIT_CALL \ 1053 COMMON_DISCARDS \ 1054 } 1055 1056 /** 1057 * PERCPU_INPUT - the percpu input sections 1058 * @cacheline: cacheline size 1059 * 1060 * The core percpu section names and core symbols which do not rely 1061 * directly upon load addresses. 1062 * 1063 * @cacheline is used to align subsections to avoid false cacheline 1064 * sharing between subsections for different purposes. 1065 */ 1066 #define PERCPU_INPUT(cacheline) \ 1067 __per_cpu_start = .; \ 1068 *(.data..percpu..first) \ 1069 . = ALIGN(PAGE_SIZE); \ 1070 *(.data..percpu..page_aligned) \ 1071 . = ALIGN(cacheline); \ 1072 *(.data..percpu..read_mostly) \ 1073 . = ALIGN(cacheline); \ 1074 *(.data..percpu) \ 1075 *(.data..percpu..shared_aligned) \ 1076 PERCPU_DECRYPTED_SECTION \ 1077 __per_cpu_end = .; 1078 1079 /** 1080 * PERCPU_VADDR - define output section for percpu area 1081 * @cacheline: cacheline size 1082 * @vaddr: explicit base address (optional) 1083 * @phdr: destination PHDR (optional) 1084 * 1085 * Macro which expands to output section for percpu area. 1086 * 1087 * @cacheline is used to align subsections to avoid false cacheline 1088 * sharing between subsections for different purposes. 1089 * 1090 * If @vaddr is not blank, it specifies explicit base address and all 1091 * percpu symbols will be offset from the given address. If blank, 1092 * @vaddr always equals @laddr + LOAD_OFFSET. 1093 * 1094 * @phdr defines the output PHDR to use if not blank. Be warned that 1095 * output PHDR is sticky. If @phdr is specified, the next output 1096 * section in the linker script will go there too. @phdr should have 1097 * a leading colon. 1098 * 1099 * Note that this macros defines __per_cpu_load as an absolute symbol. 1100 * If there is no need to put the percpu section at a predetermined 1101 * address, use PERCPU_SECTION. 1102 */ 1103 #define PERCPU_VADDR(cacheline, vaddr, phdr) \ 1104 __per_cpu_load = .; \ 1105 .data..percpu vaddr : AT(__per_cpu_load - LOAD_OFFSET) { \ 1106 PERCPU_INPUT(cacheline) \ 1107 } phdr \ 1108 . = __per_cpu_load + SIZEOF(.data..percpu); 1109 1110 /** 1111 * PERCPU_SECTION - define output section for percpu area, simple version 1112 * @cacheline: cacheline size 1113 * 1114 * Align to PAGE_SIZE and outputs output section for percpu area. This 1115 * macro doesn't manipulate @vaddr or @phdr and __per_cpu_load and 1116 * __per_cpu_start will be identical. 1117 * 1118 * This macro is equivalent to ALIGN(PAGE_SIZE); PERCPU_VADDR(@cacheline,,) 1119 * except that __per_cpu_load is defined as a relative symbol against 1120 * .data..percpu which is required for relocatable x86_32 configuration. 1121 */ 1122 #define PERCPU_SECTION(cacheline) \ 1123 . = ALIGN(PAGE_SIZE); \ 1124 .data..percpu : AT(ADDR(.data..percpu) - LOAD_OFFSET) { \ 1125 __per_cpu_load = .; \ 1126 PERCPU_INPUT(cacheline) \ 1127 } 1128 1129 1130 /* 1131 * Definition of the high level *_SECTION macros 1132 * They will fit only a subset of the architectures 1133 */ 1134 1135 1136 /* 1137 * Writeable data. 1138 * All sections are combined in a single .data section. 1139 * The sections following CONSTRUCTORS are arranged so their 1140 * typical alignment matches. 1141 * A cacheline is typical/always less than a PAGE_SIZE so 1142 * the sections that has this restriction (or similar) 1143 * is located before the ones requiring PAGE_SIZE alignment. 1144 * NOSAVE_DATA starts and ends with a PAGE_SIZE alignment which 1145 * matches the requirement of PAGE_ALIGNED_DATA. 1146 * 1147 * use 0 as page_align if page_aligned data is not used */ 1148 #define RW_DATA(cacheline, pagealigned, inittask) \ 1149 . = ALIGN(PAGE_SIZE); \ 1150 .data : AT(ADDR(.data) - LOAD_OFFSET) { \ 1151 INIT_TASK_DATA(inittask) \ 1152 NOSAVE_DATA \ 1153 PAGE_ALIGNED_DATA(pagealigned) \ 1154 CACHELINE_ALIGNED_DATA(cacheline) \ 1155 READ_MOSTLY_DATA(cacheline) \ 1156 DATA_DATA \ 1157 CONSTRUCTORS \ 1158 } \ 1159 BUG_TABLE \ 1160 1161 #define INIT_TEXT_SECTION(inittext_align) \ 1162 . = ALIGN(inittext_align); \ 1163 .init.text : AT(ADDR(.init.text) - LOAD_OFFSET) { \ 1164 _sinittext = .; \ 1165 INIT_TEXT \ 1166 _einittext = .; \ 1167 } 1168 1169 #define INIT_DATA_SECTION(initsetup_align) \ 1170 .init.data : AT(ADDR(.init.data) - LOAD_OFFSET) { \ 1171 INIT_DATA \ 1172 INIT_SETUP(initsetup_align) \ 1173 INIT_CALLS \ 1174 CON_INITCALL \ 1175 INIT_RAM_FS \ 1176 } 1177 1178 #define BSS_SECTION(sbss_align, bss_align, stop_align) \ 1179 . = ALIGN(sbss_align); \ 1180 __bss_start = .; \ 1181 SBSS(sbss_align) \ 1182 BSS(bss_align) \ 1183 . = ALIGN(stop_align); \ 1184 __bss_stop = .; 1185