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 *(.data..decrypted) \ 335 *(.ref.data) \ 336 *(.data..shared_aligned) /* percpu related */ \ 337 MEM_KEEP(init.data*) \ 338 MEM_KEEP(exit.data*) \ 339 *(.data.unlikely) \ 340 __start_once = .; \ 341 *(.data.once) \ 342 __end_once = .; \ 343 STRUCT_ALIGN(); \ 344 *(__tracepoints) \ 345 *(__vendor_hooks) \ 346 /* implement dynamic printk debug */ \ 347 . = ALIGN(8); \ 348 __start___dyndbg = .; \ 349 KEEP(*(__dyndbg)) \ 350 __stop___dyndbg = .; \ 351 LIKELY_PROFILE() \ 352 BRANCH_PROFILE() \ 353 TRACE_PRINTKS() \ 354 BPF_RAW_TP() \ 355 TRACEPOINT_STR() 356 357 /* 358 * Data section helpers 359 */ 360 #define NOSAVE_DATA \ 361 . = ALIGN(PAGE_SIZE); \ 362 __nosave_begin = .; \ 363 *(.data..nosave) \ 364 . = ALIGN(PAGE_SIZE); \ 365 __nosave_end = .; 366 367 #define PAGE_ALIGNED_DATA(page_align) \ 368 . = ALIGN(page_align); \ 369 *(.data..page_aligned) \ 370 . = ALIGN(page_align); 371 372 #define READ_MOSTLY_DATA(align) \ 373 . = ALIGN(align); \ 374 *(.data..read_mostly) \ 375 . = ALIGN(align); 376 377 #define CACHELINE_ALIGNED_DATA(align) \ 378 . = ALIGN(align); \ 379 *(.data..cacheline_aligned) 380 381 #define INIT_TASK_DATA(align) \ 382 . = ALIGN(align); \ 383 __start_init_task = .; \ 384 init_thread_union = .; \ 385 init_stack = .; \ 386 KEEP(*(.data..init_task)) \ 387 KEEP(*(.data..init_thread_info)) \ 388 . = __start_init_task + THREAD_SIZE; \ 389 __end_init_task = .; 390 391 #define JUMP_TABLE_DATA \ 392 . = ALIGN(8); \ 393 __start___jump_table = .; \ 394 KEEP(*(__jump_table)) \ 395 __stop___jump_table = .; 396 397 #define STATIC_CALL_DATA \ 398 . = ALIGN(8); \ 399 __start_static_call_sites = .; \ 400 KEEP(*(.static_call_sites)) \ 401 __stop_static_call_sites = .; \ 402 __start_static_call_tramp_key = .; \ 403 KEEP(*(.static_call_tramp_key)) \ 404 __stop_static_call_tramp_key = .; 405 406 /* 407 * Allow architectures to handle ro_after_init data on their 408 * own by defining an empty RO_AFTER_INIT_DATA. 409 */ 410 #ifndef RO_AFTER_INIT_DATA 411 #define RO_AFTER_INIT_DATA \ 412 . = ALIGN(8); \ 413 __start_ro_after_init = .; \ 414 *(.data..ro_after_init .data.rel.ro.*) \ 415 JUMP_TABLE_DATA \ 416 STATIC_CALL_DATA \ 417 __end_ro_after_init = .; 418 #endif 419 420 /* 421 * Read only Data 422 */ 423 #define RO_DATA(align) \ 424 . = ALIGN((align)); \ 425 .rodata : AT(ADDR(.rodata) - LOAD_OFFSET) { \ 426 __start_rodata = .; \ 427 *(.rodata) *(.rodata.*) \ 428 SCHED_DATA \ 429 RO_AFTER_INIT_DATA /* Read only after init */ \ 430 . = ALIGN(8); \ 431 __start___tracepoints_ptrs = .; \ 432 KEEP(*(__tracepoints_ptrs)) /* Tracepoints: pointer array */ \ 433 __stop___tracepoints_ptrs = .; \ 434 *(__tracepoints_strings)/* Tracepoints: strings */ \ 435 } \ 436 \ 437 .rodata1 : AT(ADDR(.rodata1) - LOAD_OFFSET) { \ 438 *(.rodata1) \ 439 } \ 440 \ 441 /* PCI quirks */ \ 442 .pci_fixup : AT(ADDR(.pci_fixup) - LOAD_OFFSET) { \ 443 __start_pci_fixups_early = .; \ 444 KEEP(*(.pci_fixup_early)) \ 445 __end_pci_fixups_early = .; \ 446 __start_pci_fixups_header = .; \ 447 KEEP(*(.pci_fixup_header)) \ 448 __end_pci_fixups_header = .; \ 449 __start_pci_fixups_final = .; \ 450 KEEP(*(.pci_fixup_final)) \ 451 __end_pci_fixups_final = .; \ 452 __start_pci_fixups_enable = .; \ 453 KEEP(*(.pci_fixup_enable)) \ 454 __end_pci_fixups_enable = .; \ 455 __start_pci_fixups_resume = .; \ 456 KEEP(*(.pci_fixup_resume)) \ 457 __end_pci_fixups_resume = .; \ 458 __start_pci_fixups_resume_early = .; \ 459 KEEP(*(.pci_fixup_resume_early)) \ 460 __end_pci_fixups_resume_early = .; \ 461 __start_pci_fixups_suspend = .; \ 462 KEEP(*(.pci_fixup_suspend)) \ 463 __end_pci_fixups_suspend = .; \ 464 __start_pci_fixups_suspend_late = .; \ 465 KEEP(*(.pci_fixup_suspend_late)) \ 466 __end_pci_fixups_suspend_late = .; \ 467 } \ 468 \ 469 /* Built-in firmware blobs */ \ 470 .builtin_fw : AT(ADDR(.builtin_fw) - LOAD_OFFSET) ALIGN(8) { \ 471 __start_builtin_fw = .; \ 472 KEEP(*(.builtin_fw)) \ 473 __end_builtin_fw = .; \ 474 } \ 475 \ 476 TRACEDATA \ 477 \ 478 /* Kernel symbol table: Normal symbols */ \ 479 __ksymtab : AT(ADDR(__ksymtab) - LOAD_OFFSET) { \ 480 __start___ksymtab = .; \ 481 KEEP(*(SORT(___ksymtab+*))) \ 482 __stop___ksymtab = .; \ 483 } \ 484 \ 485 /* Kernel symbol table: GPL-only symbols */ \ 486 __ksymtab_gpl : AT(ADDR(__ksymtab_gpl) - LOAD_OFFSET) { \ 487 __start___ksymtab_gpl = .; \ 488 KEEP(*(SORT(___ksymtab_gpl+*))) \ 489 __stop___ksymtab_gpl = .; \ 490 } \ 491 \ 492 /* Kernel symbol table: Normal unused symbols */ \ 493 __ksymtab_unused : AT(ADDR(__ksymtab_unused) - LOAD_OFFSET) { \ 494 __start___ksymtab_unused = .; \ 495 KEEP(*(SORT(___ksymtab_unused+*))) \ 496 __stop___ksymtab_unused = .; \ 497 } \ 498 \ 499 /* Kernel symbol table: GPL-only unused symbols */ \ 500 __ksymtab_unused_gpl : AT(ADDR(__ksymtab_unused_gpl) - LOAD_OFFSET) { \ 501 __start___ksymtab_unused_gpl = .; \ 502 KEEP(*(SORT(___ksymtab_unused_gpl+*))) \ 503 __stop___ksymtab_unused_gpl = .; \ 504 } \ 505 \ 506 /* Kernel symbol table: GPL-future-only symbols */ \ 507 __ksymtab_gpl_future : AT(ADDR(__ksymtab_gpl_future) - LOAD_OFFSET) { \ 508 __start___ksymtab_gpl_future = .; \ 509 KEEP(*(SORT(___ksymtab_gpl_future+*))) \ 510 __stop___ksymtab_gpl_future = .; \ 511 } \ 512 \ 513 /* Kernel symbol table: Normal symbols */ \ 514 __kcrctab : AT(ADDR(__kcrctab) - LOAD_OFFSET) { \ 515 __start___kcrctab = .; \ 516 KEEP(*(SORT(___kcrctab+*))) \ 517 __stop___kcrctab = .; \ 518 } \ 519 \ 520 /* Kernel symbol table: GPL-only symbols */ \ 521 __kcrctab_gpl : AT(ADDR(__kcrctab_gpl) - LOAD_OFFSET) { \ 522 __start___kcrctab_gpl = .; \ 523 KEEP(*(SORT(___kcrctab_gpl+*))) \ 524 __stop___kcrctab_gpl = .; \ 525 } \ 526 \ 527 /* Kernel symbol table: Normal unused symbols */ \ 528 __kcrctab_unused : AT(ADDR(__kcrctab_unused) - LOAD_OFFSET) { \ 529 __start___kcrctab_unused = .; \ 530 KEEP(*(SORT(___kcrctab_unused+*))) \ 531 __stop___kcrctab_unused = .; \ 532 } \ 533 \ 534 /* Kernel symbol table: GPL-only unused symbols */ \ 535 __kcrctab_unused_gpl : AT(ADDR(__kcrctab_unused_gpl) - LOAD_OFFSET) { \ 536 __start___kcrctab_unused_gpl = .; \ 537 KEEP(*(SORT(___kcrctab_unused_gpl+*))) \ 538 __stop___kcrctab_unused_gpl = .; \ 539 } \ 540 \ 541 /* Kernel symbol table: GPL-future-only symbols */ \ 542 __kcrctab_gpl_future : AT(ADDR(__kcrctab_gpl_future) - LOAD_OFFSET) { \ 543 __start___kcrctab_gpl_future = .; \ 544 KEEP(*(SORT(___kcrctab_gpl_future+*))) \ 545 __stop___kcrctab_gpl_future = .; \ 546 } \ 547 \ 548 /* Kernel symbol table: strings */ \ 549 __ksymtab_strings : AT(ADDR(__ksymtab_strings) - LOAD_OFFSET) { \ 550 *(__ksymtab_strings) \ 551 } \ 552 \ 553 /* __*init sections */ \ 554 __init_rodata : AT(ADDR(__init_rodata) - LOAD_OFFSET) { \ 555 *(.ref.rodata) \ 556 MEM_KEEP(init.rodata) \ 557 MEM_KEEP(exit.rodata) \ 558 } \ 559 \ 560 /* Built-in module parameters. */ \ 561 __param : AT(ADDR(__param) - LOAD_OFFSET) { \ 562 __start___param = .; \ 563 KEEP(*(__param)) \ 564 __stop___param = .; \ 565 } \ 566 \ 567 /* Built-in module versions. */ \ 568 __modver : AT(ADDR(__modver) - LOAD_OFFSET) { \ 569 __start___modver = .; \ 570 KEEP(*(__modver)) \ 571 __stop___modver = .; \ 572 } \ 573 \ 574 RO_EXCEPTION_TABLE \ 575 NOTES \ 576 BTF \ 577 \ 578 . = ALIGN((align)); \ 579 __end_rodata = .; 580 581 582 /* 583 * .text..L.cfi.jumptable.* contain Control-Flow Integrity (CFI) 584 * jump table entries. 585 */ 586 #ifdef CONFIG_CFI_CLANG 587 #define TEXT_CFI_JT \ 588 . = ALIGN(PMD_SIZE); \ 589 __cfi_jt_start = .; \ 590 *(.text..L.cfi.jumptable .text..L.cfi.jumptable.*) \ 591 . = ALIGN(PMD_SIZE); \ 592 __cfi_jt_end = .; 593 #else 594 #define TEXT_CFI_JT 595 #endif 596 597 /* 598 * Non-instrumentable text section 599 */ 600 #define NOINSTR_TEXT \ 601 ALIGN_FUNCTION(); \ 602 __noinstr_text_start = .; \ 603 *(.noinstr.text) \ 604 __noinstr_text_end = .; 605 606 /* 607 * .text section. Map to function alignment to avoid address changes 608 * during second ld run in second ld pass when generating System.map 609 * 610 * TEXT_MAIN here will match .text.fixup and .text.unlikely if dead 611 * code elimination is enabled, so these sections should be converted 612 * to use ".." first. 613 */ 614 #define TEXT_TEXT \ 615 ALIGN_FUNCTION(); \ 616 *(.text.hot .text.hot.*) \ 617 *(TEXT_MAIN .text.fixup) \ 618 *(.text.unlikely .text.unlikely.*) \ 619 *(.text.unknown .text.unknown.*) \ 620 NOINSTR_TEXT \ 621 *(.text..refcount) \ 622 *(.ref.text) \ 623 *(.text.asan.* .text.tsan.*) \ 624 TEXT_CFI_JT \ 625 MEM_KEEP(init.text*) \ 626 MEM_KEEP(exit.text*) \ 627 628 629 /* sched.text is aling to function alignment to secure we have same 630 * address even at second ld pass when generating System.map */ 631 #define SCHED_TEXT \ 632 ALIGN_FUNCTION(); \ 633 __sched_text_start = .; \ 634 *(.sched.text) \ 635 __sched_text_end = .; 636 637 /* spinlock.text is aling to function alignment to secure we have same 638 * address even at second ld pass when generating System.map */ 639 #define LOCK_TEXT \ 640 ALIGN_FUNCTION(); \ 641 __lock_text_start = .; \ 642 *(.spinlock.text) \ 643 __lock_text_end = .; 644 645 #define CPUIDLE_TEXT \ 646 ALIGN_FUNCTION(); \ 647 __cpuidle_text_start = .; \ 648 *(.cpuidle.text) \ 649 __cpuidle_text_end = .; 650 651 #define KPROBES_TEXT \ 652 ALIGN_FUNCTION(); \ 653 __kprobes_text_start = .; \ 654 *(.kprobes.text) \ 655 __kprobes_text_end = .; 656 657 #define ENTRY_TEXT \ 658 ALIGN_FUNCTION(); \ 659 __entry_text_start = .; \ 660 *(.entry.text) \ 661 __entry_text_end = .; 662 663 #define IRQENTRY_TEXT \ 664 ALIGN_FUNCTION(); \ 665 __irqentry_text_start = .; \ 666 *(.irqentry.text) \ 667 __irqentry_text_end = .; 668 669 #define SOFTIRQENTRY_TEXT \ 670 ALIGN_FUNCTION(); \ 671 __softirqentry_text_start = .; \ 672 *(.softirqentry.text) \ 673 __softirqentry_text_end = .; 674 675 #define STATIC_CALL_TEXT \ 676 ALIGN_FUNCTION(); \ 677 __static_call_text_start = .; \ 678 *(.static_call.text) \ 679 __static_call_text_end = .; 680 681 /* Section used for early init (in .S files) */ 682 #define HEAD_TEXT KEEP(*(.head.text)) 683 684 #define HEAD_TEXT_SECTION \ 685 .head.text : AT(ADDR(.head.text) - LOAD_OFFSET) { \ 686 HEAD_TEXT \ 687 } 688 689 /* 690 * Exception table 691 */ 692 #define EXCEPTION_TABLE(align) \ 693 . = ALIGN(align); \ 694 __ex_table : AT(ADDR(__ex_table) - LOAD_OFFSET) { \ 695 __start___ex_table = .; \ 696 KEEP(*(__ex_table)) \ 697 __stop___ex_table = .; \ 698 } 699 700 /* 701 * .BTF 702 */ 703 #ifdef CONFIG_DEBUG_INFO_BTF 704 #define BTF \ 705 .BTF : AT(ADDR(.BTF) - LOAD_OFFSET) { \ 706 __start_BTF = .; \ 707 KEEP(*(.BTF)) \ 708 __stop_BTF = .; \ 709 } \ 710 . = ALIGN(4); \ 711 .BTF_ids : AT(ADDR(.BTF_ids) - LOAD_OFFSET) { \ 712 *(.BTF_ids) \ 713 } 714 #else 715 #define BTF 716 #endif 717 718 /* 719 * Init task 720 */ 721 #define INIT_TASK_DATA_SECTION(align) \ 722 . = ALIGN(align); \ 723 .data..init_task : AT(ADDR(.data..init_task) - LOAD_OFFSET) { \ 724 INIT_TASK_DATA(align) \ 725 } 726 727 #ifdef CONFIG_CONSTRUCTORS 728 #define KERNEL_CTORS() . = ALIGN(8); \ 729 __ctors_start = .; \ 730 KEEP(*(SORT(.ctors.*))) \ 731 KEEP(*(.ctors)) \ 732 KEEP(*(SORT(.init_array.*))) \ 733 KEEP(*(.init_array)) \ 734 __ctors_end = .; 735 #else 736 #define KERNEL_CTORS() 737 #endif 738 739 /* init and exit section handling */ 740 #define INIT_DATA \ 741 KEEP(*(SORT(___kentry+*))) \ 742 *(.init.data init.data.*) \ 743 MEM_DISCARD(init.data*) \ 744 KERNEL_CTORS() \ 745 MCOUNT_REC() \ 746 *(.init.rodata .init.rodata.*) \ 747 FTRACE_EVENTS() \ 748 TRACE_SYSCALLS() \ 749 KPROBE_BLACKLIST() \ 750 ERROR_INJECT_WHITELIST() \ 751 MEM_DISCARD(init.rodata) \ 752 CLK_OF_TABLES() \ 753 RESERVEDMEM_OF_TABLES() \ 754 TIMER_OF_TABLES() \ 755 CPU_METHOD_OF_TABLES() \ 756 CPUIDLE_METHOD_OF_TABLES() \ 757 KERNEL_DTB() \ 758 IRQCHIP_OF_MATCH_TABLE() \ 759 ACPI_PROBE_TABLE(irqchip) \ 760 ACPI_PROBE_TABLE(timer) \ 761 THERMAL_TABLE(governor) \ 762 EARLYCON_TABLE() \ 763 LSM_TABLE() \ 764 EARLY_LSM_TABLE() \ 765 KUNIT_TABLE() 766 767 #define INIT_TEXT \ 768 *(.init.text .init.text.*) \ 769 *(.text.startup) \ 770 MEM_DISCARD(init.text*) 771 772 #define EXIT_DATA \ 773 *(.exit.data .exit.data.*) \ 774 *(.fini_array .fini_array.*) \ 775 *(.dtors .dtors.*) \ 776 MEM_DISCARD(exit.data*) \ 777 MEM_DISCARD(exit.rodata*) 778 779 #define EXIT_TEXT \ 780 *(.exit.text) \ 781 *(.text.exit) \ 782 MEM_DISCARD(exit.text) 783 784 #define EXIT_CALL \ 785 *(.exitcall.exit) 786 787 /* 788 * bss (Block Started by Symbol) - uninitialized data 789 * zeroed during startup 790 */ 791 #define SBSS(sbss_align) \ 792 . = ALIGN(sbss_align); \ 793 .sbss : AT(ADDR(.sbss) - LOAD_OFFSET) { \ 794 *(.dynsbss) \ 795 *(SBSS_MAIN) \ 796 *(.scommon) \ 797 } 798 799 /* 800 * Allow archectures to redefine BSS_FIRST_SECTIONS to add extra 801 * sections to the front of bss. 802 */ 803 #ifndef BSS_FIRST_SECTIONS 804 #define BSS_FIRST_SECTIONS 805 #endif 806 807 #define BSS(bss_align) \ 808 . = ALIGN(bss_align); \ 809 .bss : AT(ADDR(.bss) - LOAD_OFFSET) { \ 810 BSS_FIRST_SECTIONS \ 811 . = ALIGN(PAGE_SIZE); \ 812 *(.bss..page_aligned) \ 813 . = ALIGN(PAGE_SIZE); \ 814 *(.dynbss) \ 815 *(BSS_MAIN) \ 816 *(COMMON) \ 817 } 818 819 /* 820 * DWARF debug sections. 821 * Symbols in the DWARF debugging sections are relative to 822 * the beginning of the section so we begin them at 0. 823 */ 824 #define DWARF_DEBUG \ 825 /* DWARF 1 */ \ 826 .debug 0 : { *(.debug) } \ 827 .line 0 : { *(.line) } \ 828 /* GNU DWARF 1 extensions */ \ 829 .debug_srcinfo 0 : { *(.debug_srcinfo) } \ 830 .debug_sfnames 0 : { *(.debug_sfnames) } \ 831 /* DWARF 1.1 and DWARF 2 */ \ 832 .debug_aranges 0 : { *(.debug_aranges) } \ 833 .debug_pubnames 0 : { *(.debug_pubnames) } \ 834 /* DWARF 2 */ \ 835 .debug_info 0 : { *(.debug_info \ 836 .gnu.linkonce.wi.*) } \ 837 .debug_abbrev 0 : { *(.debug_abbrev) } \ 838 .debug_line 0 : { *(.debug_line) } \ 839 .debug_frame 0 : { *(.debug_frame) } \ 840 .debug_str 0 : { *(.debug_str) } \ 841 .debug_loc 0 : { *(.debug_loc) } \ 842 .debug_macinfo 0 : { *(.debug_macinfo) } \ 843 .debug_pubtypes 0 : { *(.debug_pubtypes) } \ 844 /* DWARF 3 */ \ 845 .debug_ranges 0 : { *(.debug_ranges) } \ 846 /* SGI/MIPS DWARF 2 extensions */ \ 847 .debug_weaknames 0 : { *(.debug_weaknames) } \ 848 .debug_funcnames 0 : { *(.debug_funcnames) } \ 849 .debug_typenames 0 : { *(.debug_typenames) } \ 850 .debug_varnames 0 : { *(.debug_varnames) } \ 851 /* GNU DWARF 2 extensions */ \ 852 .debug_gnu_pubnames 0 : { *(.debug_gnu_pubnames) } \ 853 .debug_gnu_pubtypes 0 : { *(.debug_gnu_pubtypes) } \ 854 /* DWARF 4 */ \ 855 .debug_types 0 : { *(.debug_types) } \ 856 /* DWARF 5 */ \ 857 .debug_addr 0 : { *(.debug_addr) } \ 858 .debug_line_str 0 : { *(.debug_line_str) } \ 859 .debug_loclists 0 : { *(.debug_loclists) } \ 860 .debug_macro 0 : { *(.debug_macro) } \ 861 .debug_names 0 : { *(.debug_names) } \ 862 .debug_rnglists 0 : { *(.debug_rnglists) } \ 863 .debug_str_offsets 0 : { *(.debug_str_offsets) } 864 865 /* Stabs debugging sections. */ 866 #define STABS_DEBUG \ 867 .stab 0 : { *(.stab) } \ 868 .stabstr 0 : { *(.stabstr) } \ 869 .stab.excl 0 : { *(.stab.excl) } \ 870 .stab.exclstr 0 : { *(.stab.exclstr) } \ 871 .stab.index 0 : { *(.stab.index) } \ 872 .stab.indexstr 0 : { *(.stab.indexstr) } 873 874 /* Required sections not related to debugging. */ 875 #define ELF_DETAILS \ 876 .comment 0 : { *(.comment) } \ 877 .symtab 0 : { *(.symtab) } \ 878 .strtab 0 : { *(.strtab) } \ 879 .shstrtab 0 : { *(.shstrtab) } 880 881 #ifdef CONFIG_GENERIC_BUG 882 #define BUG_TABLE \ 883 . = ALIGN(8); \ 884 __bug_table : AT(ADDR(__bug_table) - LOAD_OFFSET) { \ 885 __start___bug_table = .; \ 886 KEEP(*(__bug_table)) \ 887 __stop___bug_table = .; \ 888 } 889 #else 890 #define BUG_TABLE 891 #endif 892 893 #ifdef CONFIG_UNWINDER_ORC 894 #define ORC_UNWIND_TABLE \ 895 . = ALIGN(4); \ 896 .orc_unwind_ip : AT(ADDR(.orc_unwind_ip) - LOAD_OFFSET) { \ 897 __start_orc_unwind_ip = .; \ 898 KEEP(*(.orc_unwind_ip)) \ 899 __stop_orc_unwind_ip = .; \ 900 } \ 901 . = ALIGN(2); \ 902 .orc_unwind : AT(ADDR(.orc_unwind) - LOAD_OFFSET) { \ 903 __start_orc_unwind = .; \ 904 KEEP(*(.orc_unwind)) \ 905 __stop_orc_unwind = .; \ 906 } \ 907 . = ALIGN(4); \ 908 .orc_lookup : AT(ADDR(.orc_lookup) - LOAD_OFFSET) { \ 909 orc_lookup = .; \ 910 . += (((SIZEOF(.text) + LOOKUP_BLOCK_SIZE - 1) / \ 911 LOOKUP_BLOCK_SIZE) + 1) * 4; \ 912 orc_lookup_end = .; \ 913 } 914 #else 915 #define ORC_UNWIND_TABLE 916 #endif 917 918 #ifdef CONFIG_PM_TRACE 919 #define TRACEDATA \ 920 . = ALIGN(4); \ 921 .tracedata : AT(ADDR(.tracedata) - LOAD_OFFSET) { \ 922 __tracedata_start = .; \ 923 KEEP(*(.tracedata)) \ 924 __tracedata_end = .; \ 925 } 926 #else 927 #define TRACEDATA 928 #endif 929 930 #define NOTES \ 931 .notes : AT(ADDR(.notes) - LOAD_OFFSET) { \ 932 __start_notes = .; \ 933 KEEP(*(.note.*)) \ 934 __stop_notes = .; \ 935 } NOTES_HEADERS \ 936 NOTES_HEADERS_RESTORE 937 938 #define INIT_SETUP(initsetup_align) \ 939 . = ALIGN(initsetup_align); \ 940 __setup_start = .; \ 941 KEEP(*(.init.setup)) \ 942 __setup_end = .; 943 944 #define INIT_CALLS_LEVEL(level) \ 945 __initcall##level##_start = .; \ 946 KEEP(*(.initcall##level##.init)) \ 947 KEEP(*(.initcall##level##s.init)) \ 948 949 #define INIT_CALLS \ 950 __initcall_start = .; \ 951 KEEP(*(.initcallearly.init)) \ 952 INIT_CALLS_LEVEL(0) \ 953 INIT_CALLS_LEVEL(1) \ 954 INIT_CALLS_LEVEL(2) \ 955 INIT_CALLS_LEVEL(3) \ 956 INIT_CALLS_LEVEL(4) \ 957 INIT_CALLS_LEVEL(5) \ 958 INIT_CALLS_LEVEL(rootfs) \ 959 INIT_CALLS_LEVEL(6) \ 960 INIT_CALLS_LEVEL(7) \ 961 __initcall_end = .; 962 963 #define CON_INITCALL \ 964 __con_initcall_start = .; \ 965 KEEP(*(.con_initcall.init)) \ 966 __con_initcall_end = .; 967 968 /* Alignment must be consistent with (kunit_suite *) in include/kunit/test.h */ 969 #define KUNIT_TABLE() \ 970 . = ALIGN(8); \ 971 __kunit_suites_start = .; \ 972 KEEP(*(.kunit_test_suites)) \ 973 __kunit_suites_end = .; 974 975 #ifdef CONFIG_BLK_DEV_INITRD 976 #define INIT_RAM_FS \ 977 . = ALIGN(4); \ 978 __initramfs_start = .; \ 979 KEEP(*(.init.ramfs)) \ 980 . = ALIGN(8); \ 981 KEEP(*(.init.ramfs.info)) 982 #else 983 #define INIT_RAM_FS 984 #endif 985 986 /* 987 * Memory encryption operates on a page basis. Since we need to clear 988 * the memory encryption mask for this section, it needs to be aligned 989 * on a page boundary and be a page-size multiple in length. 990 * 991 * Note: We use a separate section so that only this section gets 992 * decrypted to avoid exposing more than we wish. 993 */ 994 #ifdef CONFIG_AMD_MEM_ENCRYPT 995 #define PERCPU_DECRYPTED_SECTION \ 996 . = ALIGN(PAGE_SIZE); \ 997 *(.data..percpu..decrypted) \ 998 . = ALIGN(PAGE_SIZE); 999 #else 1000 #define PERCPU_DECRYPTED_SECTION 1001 #endif 1002 1003 1004 /* 1005 * Default discarded sections. 1006 * 1007 * Some archs want to discard exit text/data at runtime rather than 1008 * link time due to cross-section references such as alt instructions, 1009 * bug table, eh_frame, etc. DISCARDS must be the last of output 1010 * section definitions so that such archs put those in earlier section 1011 * definitions. 1012 */ 1013 #ifdef RUNTIME_DISCARD_EXIT 1014 #define EXIT_DISCARDS 1015 #else 1016 #define EXIT_DISCARDS \ 1017 EXIT_TEXT \ 1018 EXIT_DATA 1019 #endif 1020 1021 /* 1022 * Clang's -fprofile-arcs, -fsanitize=kernel-address, and 1023 * -fsanitize=thread produce unwanted sections (.eh_frame 1024 * and .init_array.*), but CONFIG_CONSTRUCTORS wants to 1025 * keep any .init_array.* sections. 1026 * https://bugs.llvm.org/show_bug.cgi?id=46478 1027 */ 1028 #if defined(CONFIG_GCOV_KERNEL) || defined(CONFIG_KASAN_GENERIC) || defined(CONFIG_KCSAN) || \ 1029 defined(CONFIG_CFI_CLANG) 1030 # ifdef CONFIG_CONSTRUCTORS 1031 # define SANITIZER_DISCARDS \ 1032 *(.eh_frame) 1033 # else 1034 # define SANITIZER_DISCARDS \ 1035 *(.init_array) *(.init_array.*) \ 1036 *(.eh_frame) 1037 # endif 1038 #else 1039 # define SANITIZER_DISCARDS 1040 #endif 1041 1042 #define COMMON_DISCARDS \ 1043 SANITIZER_DISCARDS \ 1044 *(.discard) \ 1045 *(.discard.*) \ 1046 *(.modinfo) \ 1047 /* ld.bfd warns about .gnu.version* even when not emitted */ \ 1048 *(.gnu.version*) \ 1049 1050 #define DISCARDS \ 1051 /DISCARD/ : { \ 1052 EXIT_DISCARDS \ 1053 EXIT_CALL \ 1054 COMMON_DISCARDS \ 1055 } 1056 1057 /** 1058 * PERCPU_INPUT - the percpu input sections 1059 * @cacheline: cacheline size 1060 * 1061 * The core percpu section names and core symbols which do not rely 1062 * directly upon load addresses. 1063 * 1064 * @cacheline is used to align subsections to avoid false cacheline 1065 * sharing between subsections for different purposes. 1066 */ 1067 #define PERCPU_INPUT(cacheline) \ 1068 __per_cpu_start = .; \ 1069 *(.data..percpu..first) \ 1070 . = ALIGN(PAGE_SIZE); \ 1071 *(.data..percpu..page_aligned) \ 1072 . = ALIGN(cacheline); \ 1073 *(.data..percpu..read_mostly) \ 1074 . = ALIGN(cacheline); \ 1075 *(.data..percpu) \ 1076 *(.data..percpu..shared_aligned) \ 1077 PERCPU_DECRYPTED_SECTION \ 1078 __per_cpu_end = .; 1079 1080 /** 1081 * PERCPU_VADDR - define output section for percpu area 1082 * @cacheline: cacheline size 1083 * @vaddr: explicit base address (optional) 1084 * @phdr: destination PHDR (optional) 1085 * 1086 * Macro which expands to output section for percpu area. 1087 * 1088 * @cacheline is used to align subsections to avoid false cacheline 1089 * sharing between subsections for different purposes. 1090 * 1091 * If @vaddr is not blank, it specifies explicit base address and all 1092 * percpu symbols will be offset from the given address. If blank, 1093 * @vaddr always equals @laddr + LOAD_OFFSET. 1094 * 1095 * @phdr defines the output PHDR to use if not blank. Be warned that 1096 * output PHDR is sticky. If @phdr is specified, the next output 1097 * section in the linker script will go there too. @phdr should have 1098 * a leading colon. 1099 * 1100 * Note that this macros defines __per_cpu_load as an absolute symbol. 1101 * If there is no need to put the percpu section at a predetermined 1102 * address, use PERCPU_SECTION. 1103 */ 1104 #define PERCPU_VADDR(cacheline, vaddr, phdr) \ 1105 __per_cpu_load = .; \ 1106 .data..percpu vaddr : AT(__per_cpu_load - LOAD_OFFSET) { \ 1107 PERCPU_INPUT(cacheline) \ 1108 } phdr \ 1109 . = __per_cpu_load + SIZEOF(.data..percpu); 1110 1111 /** 1112 * PERCPU_SECTION - define output section for percpu area, simple version 1113 * @cacheline: cacheline size 1114 * 1115 * Align to PAGE_SIZE and outputs output section for percpu area. This 1116 * macro doesn't manipulate @vaddr or @phdr and __per_cpu_load and 1117 * __per_cpu_start will be identical. 1118 * 1119 * This macro is equivalent to ALIGN(PAGE_SIZE); PERCPU_VADDR(@cacheline,,) 1120 * except that __per_cpu_load is defined as a relative symbol against 1121 * .data..percpu which is required for relocatable x86_32 configuration. 1122 */ 1123 #define PERCPU_SECTION(cacheline) \ 1124 . = ALIGN(PAGE_SIZE); \ 1125 .data..percpu : AT(ADDR(.data..percpu) - LOAD_OFFSET) { \ 1126 __per_cpu_load = .; \ 1127 PERCPU_INPUT(cacheline) \ 1128 } 1129 1130 1131 /* 1132 * Definition of the high level *_SECTION macros 1133 * They will fit only a subset of the architectures 1134 */ 1135 1136 1137 /* 1138 * Writeable data. 1139 * All sections are combined in a single .data section. 1140 * The sections following CONSTRUCTORS are arranged so their 1141 * typical alignment matches. 1142 * A cacheline is typical/always less than a PAGE_SIZE so 1143 * the sections that has this restriction (or similar) 1144 * is located before the ones requiring PAGE_SIZE alignment. 1145 * NOSAVE_DATA starts and ends with a PAGE_SIZE alignment which 1146 * matches the requirement of PAGE_ALIGNED_DATA. 1147 * 1148 * use 0 as page_align if page_aligned data is not used */ 1149 #define RW_DATA(cacheline, pagealigned, inittask) \ 1150 . = ALIGN(PAGE_SIZE); \ 1151 .data : AT(ADDR(.data) - LOAD_OFFSET) { \ 1152 INIT_TASK_DATA(inittask) \ 1153 NOSAVE_DATA \ 1154 PAGE_ALIGNED_DATA(pagealigned) \ 1155 CACHELINE_ALIGNED_DATA(cacheline) \ 1156 READ_MOSTLY_DATA(cacheline) \ 1157 DATA_DATA \ 1158 CONSTRUCTORS \ 1159 } \ 1160 BUG_TABLE \ 1161 1162 #define INIT_TEXT_SECTION(inittext_align) \ 1163 . = ALIGN(inittext_align); \ 1164 .init.text : AT(ADDR(.init.text) - LOAD_OFFSET) { \ 1165 _sinittext = .; \ 1166 INIT_TEXT \ 1167 _einittext = .; \ 1168 } 1169 1170 #define INIT_DATA_SECTION(initsetup_align) \ 1171 .init.data : AT(ADDR(.init.data) - LOAD_OFFSET) { \ 1172 INIT_DATA \ 1173 INIT_SETUP(initsetup_align) \ 1174 INIT_CALLS \ 1175 CON_INITCALL \ 1176 INIT_RAM_FS \ 1177 } 1178 1179 #define BSS_SECTION(sbss_align, bss_align, stop_align) \ 1180 . = ALIGN(sbss_align); \ 1181 __bss_start = .; \ 1182 SBSS(sbss_align) \ 1183 BSS(bss_align) \ 1184 . = ALIGN(stop_align); \ 1185 __bss_stop = .; 1186