| blob | 54504013c74915c2ed923fb3afde024a69cdae6b |
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 requirements]
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 */
53 #include <asm-generic/codetag.lds.h>
55 #ifndef LOAD_OFFSET
56 #define LOAD_OFFSET 0
57 #endif
59 /*
60 * Only some architectures want to have the .notes segment visible in
61 * a separate PT_NOTE ELF Program Header. When this happens, it needs
62 * to be visible in both the kernel text's PT_LOAD and the PT_NOTE
63 * Program Headers. In this case, though, the PT_LOAD needs to be made
64 * the default again so that all the following sections don't also end
65 * up in the PT_NOTE Program Header.
66 */
67 #ifdef EMITS_PT_NOTE
68 #define NOTES_HEADERS :text :note
69 #define NOTES_HEADERS_RESTORE __restore_ph : { *(.__restore_ph) } :text
70 #else
71 #define NOTES_HEADERS
72 #define NOTES_HEADERS_RESTORE
73 #endif
75 /*
76 * Some architectures have non-executable read-only exception tables.
77 * They can be added to the RO_DATA segment by specifying their desired
78 * alignment.
79 */
80 #ifdef RO_EXCEPTION_TABLE_ALIGN
81 #define RO_EXCEPTION_TABLE EXCEPTION_TABLE(RO_EXCEPTION_TABLE_ALIGN)
82 #else
83 #define RO_EXCEPTION_TABLE
84 #endif
86 /* Align . function alignment. */
87 #define ALIGN_FUNCTION() . = ALIGN(CONFIG_FUNCTION_ALIGNMENT)
89 /*
90 * LD_DEAD_CODE_DATA_ELIMINATION option enables -fdata-sections, which
91 * generates .data.identifier sections, which need to be pulled in with
92 * .data. We don't want to pull in .data..other sections, which Linux
93 * has defined. Same for text and bss.
94 *
95 * With LTO_CLANG, the linker also splits sections by default, so we need
96 * these macros to combine the sections during the final link.
97 *
98 * With AUTOFDO_CLANG and PROPELLER_CLANG, by default, the linker splits
99 * text sections and regroups functions into subsections.
100 *
101 * RODATA_MAIN is not used because existing code already defines .rodata.x
102 * sections to be brought in with rodata.
103 */
104 #if defined(CONFIG_LD_DEAD_CODE_DATA_ELIMINATION) || defined(CONFIG_LTO_CLANG) || \
105 defined(CONFIG_AUTOFDO_CLANG) || defined(CONFIG_PROPELLER_CLANG)
106 #define TEXT_MAIN .text .text.[0-9a-zA-Z_]*
107 #else
108 #define TEXT_MAIN .text
109 #endif
110 #if defined(CONFIG_LD_DEAD_CODE_DATA_ELIMINATION) || defined(CONFIG_LTO_CLANG)
111 #define DATA_MAIN .data .data.[0-9a-zA-Z_]* .data..L* .data..compoundliteral* .data.$__unnamed_* .data.$L*
112 #define SDATA_MAIN .sdata .sdata.[0-9a-zA-Z_]*
113 #define RODATA_MAIN .rodata .rodata.[0-9a-zA-Z_]* .rodata..L*
114 #define BSS_MAIN .bss .bss.[0-9a-zA-Z_]* .bss..L* .bss..compoundliteral*
115 #define SBSS_MAIN .sbss .sbss.[0-9a-zA-Z_]*
116 #else
117 #define DATA_MAIN .data
118 #define SDATA_MAIN .sdata
119 #define RODATA_MAIN .rodata
120 #define BSS_MAIN .bss
121 #define SBSS_MAIN .sbss
122 #endif
124 /*
125 * GCC 4.5 and later have a 32 bytes section alignment for structures.
126 * Except GCC 4.9, that feels the need to align on 64 bytes.
127 */
128 #define STRUCT_ALIGNMENT 32
129 #define STRUCT_ALIGN() . = ALIGN(STRUCT_ALIGNMENT)
131 /*
132 * The order of the sched class addresses are important, as they are
133 * used to determine the order of the priority of each sched class in
134 * relation to each other.
135 */
136 #define SCHED_DATA \
137 STRUCT_ALIGN(); \
138 __sched_class_highest = .; \
139 *(__stop_sched_class) \
140 *(__dl_sched_class) \
141 *(__rt_sched_class) \
142 *(__fair_sched_class) \
143 *(__ext_sched_class) \
144 *(__idle_sched_class) \
145 __sched_class_lowest = .;
147 /* The actual configuration determine if the init/exit sections
148 * are handled as text/data or they can be discarded (which
149 * often happens at runtime)
150 */
152 #ifndef CONFIG_HAVE_DYNAMIC_FTRACE_NO_PATCHABLE
153 #define KEEP_PATCHABLE KEEP(*(__patchable_function_entries))
154 #define PATCHABLE_DISCARDS
155 #else
156 #define KEEP_PATCHABLE
157 #define PATCHABLE_DISCARDS *(__patchable_function_entries)
158 #endif
160 #ifndef CONFIG_ARCH_SUPPORTS_CFI_CLANG
161 /*
162 * Simply points to ftrace_stub, but with the proper protocol.
163 * Defined by the linker script in linux/vmlinux.lds.h
164 */
165 #define FTRACE_STUB_HACK ftrace_stub_graph = ftrace_stub;
166 #else
167 #define FTRACE_STUB_HACK
168 #endif
170 #ifdef CONFIG_FTRACE_MCOUNT_RECORD
171 /*
172 * The ftrace call sites are logged to a section whose name depends on the
173 * compiler option used. A given kernel image will only use one, AKA
174 * FTRACE_CALLSITE_SECTION. We capture all of them here to avoid header
175 * dependencies for FTRACE_CALLSITE_SECTION's definition.
176 *
177 * ftrace_ops_list_func will be defined as arch_ftrace_ops_list_func
178 * as some archs will have a different prototype for that function
179 * but ftrace_ops_list_func() will have a single prototype.
180 */
181 #define MCOUNT_REC() . = ALIGN(8); \
182 __start_mcount_loc = .; \
183 KEEP(*(__mcount_loc)) \
184 KEEP_PATCHABLE \
185 __stop_mcount_loc = .; \
186 FTRACE_STUB_HACK \
187 ftrace_ops_list_func = arch_ftrace_ops_list_func;
188 #else
189 # ifdef CONFIG_FUNCTION_TRACER
190 # define MCOUNT_REC() FTRACE_STUB_HACK \
191 ftrace_ops_list_func = arch_ftrace_ops_list_func;
192 # else
193 # define MCOUNT_REC()
194 # endif
195 #endif
197 #define BOUNDED_SECTION_PRE_LABEL(_sec_, _label_, _BEGIN_, _END_) \
198 _BEGIN_##_label_ = .; \
199 KEEP(*(_sec_)) \
200 _END_##_label_ = .;
202 #define BOUNDED_SECTION_POST_LABEL(_sec_, _label_, _BEGIN_, _END_) \
203 _label_##_BEGIN_ = .; \
204 KEEP(*(_sec_)) \
205 _label_##_END_ = .;
207 #define BOUNDED_SECTION_BY(_sec_, _label_) \
208 BOUNDED_SECTION_PRE_LABEL(_sec_, _label_, __start, __stop)
210 #define BOUNDED_SECTION(_sec) BOUNDED_SECTION_BY(_sec, _sec)
212 #define HEADERED_SECTION_PRE_LABEL(_sec_, _label_, _BEGIN_, _END_, _HDR_) \
213 _HDR_##_label_ = .; \
214 KEEP(*(.gnu.linkonce.##_sec_)) \
215 BOUNDED_SECTION_PRE_LABEL(_sec_, _label_, _BEGIN_, _END_)
217 #define HEADERED_SECTION_POST_LABEL(_sec_, _label_, _BEGIN_, _END_, _HDR_) \
218 _label_##_HDR_ = .; \
219 KEEP(*(.gnu.linkonce.##_sec_)) \
220 BOUNDED_SECTION_POST_LABEL(_sec_, _label_, _BEGIN_, _END_)
222 #define HEADERED_SECTION_BY(_sec_, _label_) \
223 HEADERED_SECTION_PRE_LABEL(_sec_, _label_, __start, __stop)
225 #define HEADERED_SECTION(_sec) HEADERED_SECTION_BY(_sec, _sec)
227 #ifdef CONFIG_TRACE_BRANCH_PROFILING
228 #define LIKELY_PROFILE() \
229 BOUNDED_SECTION_BY(_ftrace_annotated_branch, _annotated_branch_profile)
230 #else
231 #define LIKELY_PROFILE()
232 #endif
234 #ifdef CONFIG_PROFILE_ALL_BRANCHES
235 #define BRANCH_PROFILE() \
236 BOUNDED_SECTION_BY(_ftrace_branch, _branch_profile)
237 #else
238 #define BRANCH_PROFILE()
239 #endif
241 #ifdef CONFIG_KPROBES
242 #define KPROBE_BLACKLIST() \
243 . = ALIGN(8); \
244 BOUNDED_SECTION(_kprobe_blacklist)
245 #else
246 #define KPROBE_BLACKLIST()
247 #endif
249 #ifdef CONFIG_FUNCTION_ERROR_INJECTION
250 #define ERROR_INJECT_WHITELIST() \
251 STRUCT_ALIGN(); \
252 BOUNDED_SECTION(_error_injection_whitelist)
253 #else
254 #define ERROR_INJECT_WHITELIST()
255 #endif
257 #ifdef CONFIG_EVENT_TRACING
258 #define FTRACE_EVENTS() \
259 . = ALIGN(8); \
260 BOUNDED_SECTION(_ftrace_events) \
261 BOUNDED_SECTION_BY(_ftrace_eval_map, _ftrace_eval_maps)
262 #else
263 #define FTRACE_EVENTS()
264 #endif
266 #ifdef CONFIG_TRACING
267 #define TRACE_PRINTKS() BOUNDED_SECTION_BY(__trace_printk_fmt, ___trace_bprintk_fmt)
268 #define TRACEPOINT_STR() BOUNDED_SECTION_BY(__tracepoint_str, ___tracepoint_str)
269 #else
270 #define TRACE_PRINTKS()
271 #define TRACEPOINT_STR()
272 #endif
274 #ifdef CONFIG_FTRACE_SYSCALLS
275 #define TRACE_SYSCALLS() \
276 . = ALIGN(8); \
277 BOUNDED_SECTION_BY(__syscalls_metadata, _syscalls_metadata)
278 #else
279 #define TRACE_SYSCALLS()
280 #endif
282 #ifdef CONFIG_BPF_EVENTS
283 #define BPF_RAW_TP() STRUCT_ALIGN(); \
284 BOUNDED_SECTION_BY(__bpf_raw_tp_map, __bpf_raw_tp)
285 #else
286 #define BPF_RAW_TP()
287 #endif
289 #ifdef CONFIG_SERIAL_EARLYCON
290 #define EARLYCON_TABLE() \
291 . = ALIGN(8); \
292 BOUNDED_SECTION_POST_LABEL(__earlycon_table, __earlycon_table, , _end)
293 #else
294 #define EARLYCON_TABLE()
295 #endif
297 #ifdef CONFIG_SECURITY
298 #define LSM_TABLE() \
299 . = ALIGN(8); \
300 BOUNDED_SECTION_PRE_LABEL(.lsm_info.init, _lsm_info, __start, __end)
302 #define EARLY_LSM_TABLE() \
303 . = ALIGN(8); \
304 BOUNDED_SECTION_PRE_LABEL(.early_lsm_info.init, _early_lsm_info, __start, __end)
305 #else
306 #define LSM_TABLE()
307 #define EARLY_LSM_TABLE()
308 #endif
310 #define ___OF_TABLE(cfg, name) _OF_TABLE_##cfg(name)
311 #define __OF_TABLE(cfg, name) ___OF_TABLE(cfg, name)
312 #define OF_TABLE(cfg, name) __OF_TABLE(IS_ENABLED(cfg), name)
313 #define _OF_TABLE_0(name)
314 #define _OF_TABLE_1(name) \
315 . = ALIGN(8); \
316 __##name##_of_table = .; \
317 KEEP(*(__##name##_of_table)) \
318 KEEP(*(__##name##_of_table_end))
320 #define TIMER_OF_TABLES() OF_TABLE(CONFIG_TIMER_OF, timer)
321 #define IRQCHIP_OF_MATCH_TABLE() OF_TABLE(CONFIG_IRQCHIP, irqchip)
322 #define CLK_OF_TABLES() OF_TABLE(CONFIG_COMMON_CLK, clk)
323 #define RESERVEDMEM_OF_TABLES() OF_TABLE(CONFIG_OF_RESERVED_MEM, reservedmem)
324 #define CPU_METHOD_OF_TABLES() OF_TABLE(CONFIG_SMP, cpu_method)
325 #define CPUIDLE_METHOD_OF_TABLES() OF_TABLE(CONFIG_CPU_IDLE, cpuidle_method)
327 #ifdef CONFIG_ACPI
328 #define ACPI_PROBE_TABLE(name) \
329 . = ALIGN(8); \
330 BOUNDED_SECTION_POST_LABEL(__##name##_acpi_probe_table, \
331 __##name##_acpi_probe_table,, _end)
332 #else
333 #define ACPI_PROBE_TABLE(name)
334 #endif
336 #ifdef CONFIG_THERMAL
337 #define THERMAL_TABLE(name) \
338 . = ALIGN(8); \
339 BOUNDED_SECTION_POST_LABEL(__##name##_thermal_table, \
340 __##name##_thermal_table,, _end)
341 #else
342 #define THERMAL_TABLE(name)
343 #endif
345 #define KERNEL_DTB() \
346 STRUCT_ALIGN(); \
347 __dtb_start = .; \
348 KEEP(*(.dtb.init.rodata)) \
349 __dtb_end = .;
351 /*
352 * .data section
353 */
354 #define DATA_DATA \
355 *(.xiptext) \
356 *(DATA_MAIN) \
357 *(.data..decrypted) \
358 *(.ref.data) \
360 *(.data..unlikely) \
361 __start_once = .; \
362 *(.data..once) \
363 __end_once = .; \
364 STRUCT_ALIGN(); \
365 *(__tracepoints) \
367 . = ALIGN(8); \
368 BOUNDED_SECTION_BY(__dyndbg_classes, ___dyndbg_classes) \
369 BOUNDED_SECTION_BY(__dyndbg, ___dyndbg) \
370 CODETAG_SECTIONS() \
371 LIKELY_PROFILE() \
372 BRANCH_PROFILE() \
373 TRACE_PRINTKS() \
374 BPF_RAW_TP() \
375 TRACEPOINT_STR() \
376 KUNIT_TABLE()
378 /*
379 * Data section helpers
380 */
381 #define NOSAVE_DATA \
382 . = ALIGN(PAGE_SIZE); \
383 __nosave_begin = .; \
384 *(.data..nosave) \
385 . = ALIGN(PAGE_SIZE); \
386 __nosave_end = .;
388 #define PAGE_ALIGNED_DATA(page_align) \
389 . = ALIGN(page_align); \
390 *(.data..page_aligned) \
391 . = ALIGN(page_align);
393 #define READ_MOSTLY_DATA(align) \
394 . = ALIGN(align); \
395 *(.data..read_mostly) \
396 . = ALIGN(align);
398 #define CACHELINE_ALIGNED_DATA(align) \
399 . = ALIGN(align); \
400 *(.data..cacheline_aligned)
402 #define INIT_TASK_DATA(align) \
403 . = ALIGN(align); \
404 __start_init_stack = .; \
405 init_thread_union = .; \
406 init_stack = .; \
407 KEEP(*(.data..init_task)) \
408 KEEP(*(.data..init_thread_info)) \
409 . = __start_init_stack + THREAD_SIZE; \
410 __end_init_stack = .;
412 #define JUMP_TABLE_DATA \
413 . = ALIGN(8); \
414 BOUNDED_SECTION_BY(__jump_table, ___jump_table)
416 #ifdef CONFIG_HAVE_STATIC_CALL_INLINE
417 #define STATIC_CALL_DATA \
418 . = ALIGN(8); \
419 BOUNDED_SECTION_BY(.static_call_sites, _static_call_sites) \
420 BOUNDED_SECTION_BY(.static_call_tramp_key, _static_call_tramp_key)
421 #else
422 #define STATIC_CALL_DATA
423 #endif
425 /*
426 * Allow architectures to handle ro_after_init data on their
427 * own by defining an empty RO_AFTER_INIT_DATA.
428 */
429 #ifndef RO_AFTER_INIT_DATA
430 #define RO_AFTER_INIT_DATA \
431 . = ALIGN(8); \
432 __start_ro_after_init = .; \
433 *(.data..ro_after_init) \
434 JUMP_TABLE_DATA \
435 STATIC_CALL_DATA \
436 __end_ro_after_init = .;
437 #endif
439 /*
440 * .kcfi_traps contains a list KCFI trap locations.
441 */
442 #ifndef KCFI_TRAPS
443 #ifdef CONFIG_ARCH_USES_CFI_TRAPS
444 #define KCFI_TRAPS \
445 __kcfi_traps : AT(ADDR(__kcfi_traps) - LOAD_OFFSET) { \
446 BOUNDED_SECTION_BY(.kcfi_traps, ___kcfi_traps) \
447 }
448 #else
449 #define KCFI_TRAPS
450 #endif
451 #endif
453 /*
454 * Read only Data
455 */
456 #define RO_DATA(align) \
457 . = ALIGN((align)); \
458 .rodata : AT(ADDR(.rodata) - LOAD_OFFSET) { \
459 __start_rodata = .; \
460 *(.rodata) *(.rodata.*) \
461 SCHED_DATA \
463 . = ALIGN(8); \
464 BOUNDED_SECTION_BY(__tracepoints_ptrs, ___tracepoints_ptrs) \
466 } \
467 \
468 .rodata1 : AT(ADDR(.rodata1) - LOAD_OFFSET) { \
469 *(.rodata1) \
470 } \
471 \
473 .pci_fixup : AT(ADDR(.pci_fixup) - LOAD_OFFSET) { \
474 BOUNDED_SECTION_PRE_LABEL(.pci_fixup_early, _pci_fixups_early, __start, __end) \
475 BOUNDED_SECTION_PRE_LABEL(.pci_fixup_header, _pci_fixups_header, __start, __end) \
476 BOUNDED_SECTION_PRE_LABEL(.pci_fixup_final, _pci_fixups_final, __start, __end) \
477 BOUNDED_SECTION_PRE_LABEL(.pci_fixup_enable, _pci_fixups_enable, __start, __end) \
478 BOUNDED_SECTION_PRE_LABEL(.pci_fixup_resume, _pci_fixups_resume, __start, __end) \
479 BOUNDED_SECTION_PRE_LABEL(.pci_fixup_suspend, _pci_fixups_suspend, __start, __end) \
480 BOUNDED_SECTION_PRE_LABEL(.pci_fixup_resume_early, _pci_fixups_resume_early, __start, __end) \
481 BOUNDED_SECTION_PRE_LABEL(.pci_fixup_suspend_late, _pci_fixups_suspend_late, __start, __end) \
482 } \
483 \
484 FW_LOADER_BUILT_IN_DATA \
485 TRACEDATA \
486 \
487 PRINTK_INDEX \
488 \
490 __ksymtab : AT(ADDR(__ksymtab) - LOAD_OFFSET) { \
491 __start___ksymtab = .; \
492 KEEP(*(SORT(___ksymtab+*))) \
493 __stop___ksymtab = .; \
494 } \
495 \
497 __ksymtab_gpl : AT(ADDR(__ksymtab_gpl) - LOAD_OFFSET) { \
498 __start___ksymtab_gpl = .; \
499 KEEP(*(SORT(___ksymtab_gpl+*))) \
500 __stop___ksymtab_gpl = .; \
501 } \
502 \
504 __kcrctab : AT(ADDR(__kcrctab) - LOAD_OFFSET) { \
505 __start___kcrctab = .; \
506 KEEP(*(SORT(___kcrctab+*))) \
507 __stop___kcrctab = .; \
508 } \
509 \
511 __kcrctab_gpl : AT(ADDR(__kcrctab_gpl) - LOAD_OFFSET) { \
512 __start___kcrctab_gpl = .; \
513 KEEP(*(SORT(___kcrctab_gpl+*))) \
514 __stop___kcrctab_gpl = .; \
515 } \
516 \
518 __ksymtab_strings : AT(ADDR(__ksymtab_strings) - LOAD_OFFSET) { \
519 *(__ksymtab_strings) \
520 } \
521 \
523 __init_rodata : AT(ADDR(__init_rodata) - LOAD_OFFSET) { \
524 *(.ref.rodata) \
525 } \
526 \
528 __param : AT(ADDR(__param) - LOAD_OFFSET) { \
529 BOUNDED_SECTION_BY(__param, ___param) \
530 } \
531 \
533 __modver : AT(ADDR(__modver) - LOAD_OFFSET) { \
534 BOUNDED_SECTION_BY(__modver, ___modver) \
535 } \
536 \
537 KCFI_TRAPS \
538 \
539 RO_EXCEPTION_TABLE \
540 NOTES \
541 BTF \
542 \
543 . = ALIGN((align)); \
544 __end_rodata = .;
547 /*
548 * Non-instrumentable text section
549 */
550 #define NOINSTR_TEXT \
551 ALIGN_FUNCTION(); \
552 __noinstr_text_start = .; \
553 *(.noinstr.text) \
554 __cpuidle_text_start = .; \
555 *(.cpuidle.text) \
556 __cpuidle_text_end = .; \
557 __noinstr_text_end = .;
559 #define TEXT_SPLIT \
560 __split_text_start = .; \
561 *(.text.split .text.split.[0-9a-zA-Z_]*) \
562 __split_text_end = .;
564 #define TEXT_UNLIKELY \
565 __unlikely_text_start = .; \
566 *(.text.unlikely .text.unlikely.*) \
567 __unlikely_text_end = .;
569 #define TEXT_HOT \
570 __hot_text_start = .; \
571 *(.text.hot .text.hot.*) \
572 __hot_text_end = .;
574 /*
575 * .text section. Map to function alignment to avoid address changes
576 * during second ld run in second ld pass when generating System.map
577 *
578 * TEXT_MAIN here will match symbols with a fixed pattern (for example,
579 * .text.hot or .text.unlikely) if dead code elimination or
580 * function-section is enabled. Match these symbols first before
581 * TEXT_MAIN to ensure they are grouped together.
582 *
583 * Also placing .text.hot section at the beginning of a page, this
584 * would help the TLB performance.
585 */
586 #define TEXT_TEXT \
587 ALIGN_FUNCTION(); \
588 *(.text.asan.* .text.tsan.*) \
589 *(.text.unknown .text.unknown.*) \
590 TEXT_SPLIT \
591 TEXT_UNLIKELY \
592 . = ALIGN(PAGE_SIZE); \
593 TEXT_HOT \
594 *(TEXT_MAIN .text.fixup) \
595 NOINSTR_TEXT \
596 *(.ref.text)
598 /* sched.text is aling to function alignment to secure we have same
599 * address even at second ld pass when generating System.map */
600 #define SCHED_TEXT \
601 ALIGN_FUNCTION(); \
602 __sched_text_start = .; \
603 *(.sched.text) \
604 __sched_text_end = .;
606 /* spinlock.text is aling to function alignment to secure we have same
607 * address even at second ld pass when generating System.map */
608 #define LOCK_TEXT \
609 ALIGN_FUNCTION(); \
610 __lock_text_start = .; \
611 *(.spinlock.text) \
612 __lock_text_end = .;
614 #define KPROBES_TEXT \
615 ALIGN_FUNCTION(); \
616 __kprobes_text_start = .; \
617 *(.kprobes.text) \
618 __kprobes_text_end = .;
620 #define ENTRY_TEXT \
621 ALIGN_FUNCTION(); \
622 __entry_text_start = .; \
623 *(.entry.text) \
624 __entry_text_end = .;
626 #define IRQENTRY_TEXT \
627 ALIGN_FUNCTION(); \
628 __irqentry_text_start = .; \
629 *(.irqentry.text) \
630 __irqentry_text_end = .;
632 #define SOFTIRQENTRY_TEXT \
633 ALIGN_FUNCTION(); \
634 __softirqentry_text_start = .; \
635 *(.softirqentry.text) \
636 __softirqentry_text_end = .;
638 #define STATIC_CALL_TEXT \
639 ALIGN_FUNCTION(); \
640 __static_call_text_start = .; \
641 *(.static_call.text) \
642 __static_call_text_end = .;
644 /* Section used for early init (in .S files) */
645 #define HEAD_TEXT KEEP(*(.head.text))
647 #define HEAD_TEXT_SECTION \
648 .head.text : AT(ADDR(.head.text) - LOAD_OFFSET) { \
649 HEAD_TEXT \
650 }
652 /*
653 * Exception table
654 */
655 #define EXCEPTION_TABLE(align) \
656 . = ALIGN(align); \
657 __ex_table : AT(ADDR(__ex_table) - LOAD_OFFSET) { \
658 BOUNDED_SECTION_BY(__ex_table, ___ex_table) \
659 }
661 /*
662 * .BTF
663 */
664 #ifdef CONFIG_DEBUG_INFO_BTF
665 #define BTF \
666 .BTF : AT(ADDR(.BTF) - LOAD_OFFSET) { \
667 BOUNDED_SECTION_BY(.BTF, _BTF) \
668 } \
669 . = ALIGN(4); \
670 .BTF_ids : AT(ADDR(.BTF_ids) - LOAD_OFFSET) { \
671 *(.BTF_ids) \
672 }
673 #else
674 #define BTF
675 #endif
677 /*
678 * Init task
679 */
680 #define INIT_TASK_DATA_SECTION(align) \
681 . = ALIGN(align); \
682 .data..init_task : AT(ADDR(.data..init_task) - LOAD_OFFSET) { \
683 INIT_TASK_DATA(align) \
684 }
686 #ifdef CONFIG_CONSTRUCTORS
687 #define KERNEL_CTORS() . = ALIGN(8); \
688 __ctors_start = .; \
689 KEEP(*(SORT(.ctors.*))) \
690 KEEP(*(.ctors)) \
691 KEEP(*(SORT(.init_array.*))) \
692 KEEP(*(.init_array)) \
693 __ctors_end = .;
694 #else
695 #define KERNEL_CTORS()
696 #endif
698 /* init and exit section handling */
699 #define INIT_DATA \
700 KEEP(*(SORT(___kentry+*))) \
701 *(.init.data .init.data.*) \
702 KERNEL_CTORS() \
703 MCOUNT_REC() \
704 *(.init.rodata .init.rodata.*) \
705 FTRACE_EVENTS() \
706 TRACE_SYSCALLS() \
707 KPROBE_BLACKLIST() \
708 ERROR_INJECT_WHITELIST() \
709 CLK_OF_TABLES() \
710 RESERVEDMEM_OF_TABLES() \
711 TIMER_OF_TABLES() \
712 CPU_METHOD_OF_TABLES() \
713 CPUIDLE_METHOD_OF_TABLES() \
714 KERNEL_DTB() \
715 IRQCHIP_OF_MATCH_TABLE() \
716 ACPI_PROBE_TABLE(irqchip) \
717 ACPI_PROBE_TABLE(timer) \
718 THERMAL_TABLE(governor) \
719 EARLYCON_TABLE() \
720 LSM_TABLE() \
721 EARLY_LSM_TABLE() \
722 KUNIT_INIT_TABLE()
724 #define INIT_TEXT \
725 *(.init.text .init.text.*) \
726 *(.text.startup)
728 #define EXIT_DATA \
729 *(.exit.data .exit.data.*) \
730 *(.fini_array .fini_array.*) \
731 *(.dtors .dtors.*) \
733 #define EXIT_TEXT \
734 *(.exit.text) \
735 *(.text.exit) \
737 #define EXIT_CALL \
738 *(.exitcall.exit)
740 /*
741 * bss (Block Started by Symbol) - uninitialized data
742 * zeroed during startup
743 */
744 #define SBSS(sbss_align) \
745 . = ALIGN(sbss_align); \
746 .sbss : AT(ADDR(.sbss) - LOAD_OFFSET) { \
747 *(.dynsbss) \
748 *(SBSS_MAIN) \
749 *(.scommon) \
750 }
752 /*
753 * Allow archectures to redefine BSS_FIRST_SECTIONS to add extra
754 * sections to the front of bss.
755 */
756 #ifndef BSS_FIRST_SECTIONS
757 #define BSS_FIRST_SECTIONS
758 #endif
760 #define BSS(bss_align) \
761 . = ALIGN(bss_align); \
762 .bss : AT(ADDR(.bss) - LOAD_OFFSET) { \
763 BSS_FIRST_SECTIONS \
764 . = ALIGN(PAGE_SIZE); \
765 *(.bss..page_aligned) \
766 . = ALIGN(PAGE_SIZE); \
767 *(.dynbss) \
768 *(BSS_MAIN) \
769 *(COMMON) \
770 }
772 /*
773 * DWARF debug sections.
774 * Symbols in the DWARF debugging sections are relative to
775 * the beginning of the section so we begin them at 0.
776 */
777 #define DWARF_DEBUG \
779 .debug 0 : { *(.debug) } \
780 .line 0 : { *(.line) } \
782 .debug_srcinfo 0 : { *(.debug_srcinfo) } \
783 .debug_sfnames 0 : { *(.debug_sfnames) } \
785 .debug_aranges 0 : { *(.debug_aranges) } \
786 .debug_pubnames 0 : { *(.debug_pubnames) } \
788 .debug_info 0 : { *(.debug_info \
789 .gnu.linkonce.wi.*) } \
790 .debug_abbrev 0 : { *(.debug_abbrev) } \
791 .debug_line 0 : { *(.debug_line) } \
792 .debug_frame 0 : { *(.debug_frame) } \
793 .debug_str 0 : { *(.debug_str) } \
794 .debug_loc 0 : { *(.debug_loc) } \
795 .debug_macinfo 0 : { *(.debug_macinfo) } \
796 .debug_pubtypes 0 : { *(.debug_pubtypes) } \
798 .debug_ranges 0 : { *(.debug_ranges) } \
800 .debug_weaknames 0 : { *(.debug_weaknames) } \
801 .debug_funcnames 0 : { *(.debug_funcnames) } \
802 .debug_typenames 0 : { *(.debug_typenames) } \
803 .debug_varnames 0 : { *(.debug_varnames) } \
805 .debug_gnu_pubnames 0 : { *(.debug_gnu_pubnames) } \
806 .debug_gnu_pubtypes 0 : { *(.debug_gnu_pubtypes) } \
808 .debug_types 0 : { *(.debug_types) } \
810 .debug_addr 0 : { *(.debug_addr) } \
811 .debug_line_str 0 : { *(.debug_line_str) } \
812 .debug_loclists 0 : { *(.debug_loclists) } \
813 .debug_macro 0 : { *(.debug_macro) } \
814 .debug_names 0 : { *(.debug_names) } \
815 .debug_rnglists 0 : { *(.debug_rnglists) } \
816 .debug_str_offsets 0 : { *(.debug_str_offsets) }
818 /* Stabs debugging sections. */
819 #define STABS_DEBUG \
820 .stab 0 : { *(.stab) } \
821 .stabstr 0 : { *(.stabstr) } \
822 .stab.excl 0 : { *(.stab.excl) } \
823 .stab.exclstr 0 : { *(.stab.exclstr) } \
824 .stab.index 0 : { *(.stab.index) } \
825 .stab.indexstr 0 : { *(.stab.indexstr) }
827 /* Required sections not related to debugging. */
828 #define ELF_DETAILS \
829 .comment 0 : { *(.comment) } \
830 .symtab 0 : { *(.symtab) } \
831 .strtab 0 : { *(.strtab) } \
832 .shstrtab 0 : { *(.shstrtab) }
834 #ifdef CONFIG_GENERIC_BUG
835 #define BUG_TABLE \
836 . = ALIGN(8); \
837 __bug_table : AT(ADDR(__bug_table) - LOAD_OFFSET) { \
838 BOUNDED_SECTION_BY(__bug_table, ___bug_table) \
839 }
840 #else
841 #define BUG_TABLE
842 #endif
844 #ifdef CONFIG_UNWINDER_ORC
845 #define ORC_UNWIND_TABLE \
846 .orc_header : AT(ADDR(.orc_header) - LOAD_OFFSET) { \
847 BOUNDED_SECTION_BY(.orc_header, _orc_header) \
848 } \
849 . = ALIGN(4); \
850 .orc_unwind_ip : AT(ADDR(.orc_unwind_ip) - LOAD_OFFSET) { \
851 BOUNDED_SECTION_BY(.orc_unwind_ip, _orc_unwind_ip) \
852 } \
853 . = ALIGN(2); \
854 .orc_unwind : AT(ADDR(.orc_unwind) - LOAD_OFFSET) { \
855 BOUNDED_SECTION_BY(.orc_unwind, _orc_unwind) \
856 } \
857 text_size = _etext - _stext; \
858 . = ALIGN(4); \
859 .orc_lookup : AT(ADDR(.orc_lookup) - LOAD_OFFSET) { \
860 orc_lookup = .; \
861 . += (((text_size + LOOKUP_BLOCK_SIZE - 1) / \
862 LOOKUP_BLOCK_SIZE) + 1) * 4; \
863 orc_lookup_end = .; \
864 }
865 #else
866 #define ORC_UNWIND_TABLE
867 #endif
869 /* Built-in firmware blobs */
870 #ifdef CONFIG_FW_LOADER
871 #define FW_LOADER_BUILT_IN_DATA \
872 .builtin_fw : AT(ADDR(.builtin_fw) - LOAD_OFFSET) ALIGN(8) { \
873 BOUNDED_SECTION_PRE_LABEL(.builtin_fw, _builtin_fw, __start, __end) \
874 }
875 #else
876 #define FW_LOADER_BUILT_IN_DATA
877 #endif
879 #ifdef CONFIG_PM_TRACE
880 #define TRACEDATA \
881 . = ALIGN(4); \
882 .tracedata : AT(ADDR(.tracedata) - LOAD_OFFSET) { \
883 BOUNDED_SECTION_POST_LABEL(.tracedata, __tracedata, _start, _end) \
884 }
885 #else
886 #define TRACEDATA
887 #endif
889 #ifdef CONFIG_PRINTK_INDEX
890 #define PRINTK_INDEX \
891 .printk_index : AT(ADDR(.printk_index) - LOAD_OFFSET) { \
892 BOUNDED_SECTION_BY(.printk_index, _printk_index) \
893 }
894 #else
895 #define PRINTK_INDEX
896 #endif
898 /*
899 * Discard .note.GNU-stack, which is emitted as PROGBITS by the compiler.
900 * Otherwise, the type of .notes section would become PROGBITS instead of NOTES.
901 *
902 * Also, discard .note.gnu.property, otherwise it forces the notes section to
903 * be 8-byte aligned which causes alignment mismatches with the kernel's custom
904 * 4-byte aligned notes.
905 */
906 #define NOTES \
907 /DISCARD/ : { \
908 *(.note.GNU-stack) \
909 *(.note.gnu.property) \
910 } \
911 .notes : AT(ADDR(.notes) - LOAD_OFFSET) { \
912 BOUNDED_SECTION_BY(.note.*, _notes) \
913 } NOTES_HEADERS \
914 NOTES_HEADERS_RESTORE
916 #define INIT_SETUP(initsetup_align) \
917 . = ALIGN(initsetup_align); \
918 BOUNDED_SECTION_POST_LABEL(.init.setup, __setup, _start, _end)
920 #define INIT_CALLS_LEVEL(level) \
921 __initcall##level##_start = .; \
922 KEEP(*(.initcall##level##.init)) \
923 KEEP(*(.initcall##level##s.init)) \
925 #define INIT_CALLS \
926 __initcall_start = .; \
927 KEEP(*(.initcallearly.init)) \
928 INIT_CALLS_LEVEL(0) \
929 INIT_CALLS_LEVEL(1) \
930 INIT_CALLS_LEVEL(2) \
931 INIT_CALLS_LEVEL(3) \
932 INIT_CALLS_LEVEL(4) \
933 INIT_CALLS_LEVEL(5) \
934 INIT_CALLS_LEVEL(rootfs) \
935 INIT_CALLS_LEVEL(6) \
936 INIT_CALLS_LEVEL(7) \
937 __initcall_end = .;
939 #define CON_INITCALL \
940 BOUNDED_SECTION_POST_LABEL(.con_initcall.init, __con_initcall, _start, _end)
942 #define NAMED_SECTION(name) \
943 . = ALIGN(8); \
944 name : AT(ADDR(name) - LOAD_OFFSET) \
945 { BOUNDED_SECTION_PRE_LABEL(name, name, __start_, __stop_) }
947 #define RUNTIME_CONST(t,x) NAMED_SECTION(runtime_##t##_##x)
949 #define RUNTIME_CONST_VARIABLES \
950 RUNTIME_CONST(shift, d_hash_shift) \
951 RUNTIME_CONST(ptr, dentry_hashtable)
953 /* Alignment must be consistent with (kunit_suite *) in include/kunit/test.h */
954 #define KUNIT_TABLE() \
955 . = ALIGN(8); \
956 BOUNDED_SECTION_POST_LABEL(.kunit_test_suites, __kunit_suites, _start, _end)
958 /* Alignment must be consistent with (kunit_suite *) in include/kunit/test.h */
959 #define KUNIT_INIT_TABLE() \
960 . = ALIGN(8); \
961 BOUNDED_SECTION_POST_LABEL(.kunit_init_test_suites, \
962 __kunit_init_suites, _start, _end)
964 #ifdef CONFIG_BLK_DEV_INITRD
965 #define INIT_RAM_FS \
966 . = ALIGN(4); \
967 __initramfs_start = .; \
968 KEEP(*(.init.ramfs)) \
969 . = ALIGN(8); \
970 KEEP(*(.init.ramfs.info))
971 #else
972 #define INIT_RAM_FS
973 #endif
975 /*
976 * Memory encryption operates on a page basis. Since we need to clear
977 * the memory encryption mask for this section, it needs to be aligned
978 * on a page boundary and be a page-size multiple in length.
979 *
980 * Note: We use a separate section so that only this section gets
981 * decrypted to avoid exposing more than we wish.
982 */
983 #ifdef CONFIG_AMD_MEM_ENCRYPT
984 #define PERCPU_DECRYPTED_SECTION \
985 . = ALIGN(PAGE_SIZE); \
986 *(.data..percpu..decrypted) \
987 . = ALIGN(PAGE_SIZE);
988 #else
989 #define PERCPU_DECRYPTED_SECTION
990 #endif
993 /*
994 * Default discarded sections.
995 *
996 * Some archs want to discard exit text/data at runtime rather than
997 * link time due to cross-section references such as alt instructions,
998 * bug table, eh_frame, etc. DISCARDS must be the last of output
999 * section definitions so that such archs put those in earlier section
1000 * definitions.
1001 */
1002 #ifdef RUNTIME_DISCARD_EXIT
1003 #define EXIT_DISCARDS
1004 #else
1005 #define EXIT_DISCARDS \
1006 EXIT_TEXT \
1007 EXIT_DATA
1008 #endif
1010 /*
1011 * Clang's -fprofile-arcs, -fsanitize=kernel-address, and
1012 * -fsanitize=thread produce unwanted sections (.eh_frame
1013 * and .init_array.*), but CONFIG_CONSTRUCTORS wants to
1014 * keep any .init_array.* sections.
1015 * https://llvm.org/pr46478
1016 */
1017 #ifdef CONFIG_UNWIND_TABLES
1018 #define DISCARD_EH_FRAME
1019 #else
1020 #define DISCARD_EH_FRAME *(.eh_frame)
1021 #endif
1022 #if defined(CONFIG_GCOV_KERNEL) || defined(CONFIG_KASAN_GENERIC) || defined(CONFIG_KCSAN)
1023 # ifdef CONFIG_CONSTRUCTORS
1024 # define SANITIZER_DISCARDS \
1025 DISCARD_EH_FRAME
1026 # else
1027 # define SANITIZER_DISCARDS \
1028 *(.init_array) *(.init_array.*) \
1029 DISCARD_EH_FRAME
1030 # endif
1031 #else
1032 # define SANITIZER_DISCARDS
1033 #endif
1035 #define COMMON_DISCARDS \
1036 SANITIZER_DISCARDS \
1037 PATCHABLE_DISCARDS \
1038 *(.discard) \
1039 *(.discard.*) \
1040 *(.export_symbol) \
1041 *(.modinfo) \
1043 *(.gnu.version*) \
1045 #define DISCARDS \
1046 /DISCARD/ : { \
1047 EXIT_DISCARDS \
1048 EXIT_CALL \
1049 COMMON_DISCARDS \
1050 }
1052 /**
1053 * PERCPU_INPUT - the percpu input sections
1054 * @cacheline: cacheline size
1055 *
1056 * The core percpu section names and core symbols which do not rely
1057 * directly upon load addresses.
1058 *
1059 * @cacheline is used to align subsections to avoid false cacheline
1060 * sharing between subsections for different purposes.
1061 */
1062 #define PERCPU_INPUT(cacheline) \
1063 __per_cpu_start = .; \
1064 *(.data..percpu..first) \
1065 . = ALIGN(PAGE_SIZE); \
1066 *(.data..percpu..page_aligned) \
1067 . = ALIGN(cacheline); \
1068 *(.data..percpu..read_mostly) \
1069 . = ALIGN(cacheline); \
1070 *(.data..percpu) \
1071 *(.data..percpu..shared_aligned) \
1072 PERCPU_DECRYPTED_SECTION \
1073 __per_cpu_end = .;
1075 /**
1076 * PERCPU_VADDR - define output section for percpu area
1077 * @cacheline: cacheline size
1078 * @vaddr: explicit base address (optional)
1079 * @phdr: destination PHDR (optional)
1080 *
1081 * Macro which expands to output section for percpu area.
1082 *
1083 * @cacheline is used to align subsections to avoid false cacheline
1084 * sharing between subsections for different purposes.
1085 *
1086 * If @vaddr is not blank, it specifies explicit base address and all
1087 * percpu symbols will be offset from the given address. If blank,
1088 * @vaddr always equals @laddr + LOAD_OFFSET.
1089 *
1090 * @phdr defines the output PHDR to use if not blank. Be warned that
1091 * output PHDR is sticky. If @phdr is specified, the next output
1092 * section in the linker script will go there too. @phdr should have
1093 * a leading colon.
1094 *
1095 * Note that this macros defines __per_cpu_load as an absolute symbol.
1096 * If there is no need to put the percpu section at a predetermined
1097 * address, use PERCPU_SECTION.
1098 */
1099 #define PERCPU_VADDR(cacheline, vaddr, phdr) \
1100 __per_cpu_load = .; \
1101 .data..percpu vaddr : AT(__per_cpu_load - LOAD_OFFSET) { \
1102 PERCPU_INPUT(cacheline) \
1103 } phdr \
1104 . = __per_cpu_load + SIZEOF(.data..percpu);
1106 /**
1107 * PERCPU_SECTION - define output section for percpu area, simple version
1108 * @cacheline: cacheline size
1109 *
1110 * Align to PAGE_SIZE and outputs output section for percpu area. This
1111 * macro doesn't manipulate @vaddr or @phdr and __per_cpu_load and
1112 * __per_cpu_start will be identical.
1113 *
1114 * This macro is equivalent to ALIGN(PAGE_SIZE); PERCPU_VADDR(@cacheline,,)
1115 * except that __per_cpu_load is defined as a relative symbol against
1116 * .data..percpu which is required for relocatable x86_32 configuration.
1117 */
1118 #define PERCPU_SECTION(cacheline) \
1119 . = ALIGN(PAGE_SIZE); \
1120 .data..percpu : AT(ADDR(.data..percpu) - LOAD_OFFSET) { \
1121 __per_cpu_load = .; \
1122 PERCPU_INPUT(cacheline) \
1123 }
1126 /*
1127 * Definition of the high level *_SECTION macros
1128 * They will fit only a subset of the architectures
1129 */
1132 /*
1133 * Writeable data.
1134 * All sections are combined in a single .data section.
1135 * The sections following CONSTRUCTORS are arranged so their
1136 * typical alignment matches.
1137 * A cacheline is typical/always less than a PAGE_SIZE so
1138 * the sections that has this restriction (or similar)
1139 * is located before the ones requiring PAGE_SIZE alignment.
1140 * NOSAVE_DATA starts and ends with a PAGE_SIZE alignment which
1141 * matches the requirement of PAGE_ALIGNED_DATA.
1142 *
1143 * use 0 as page_align if page_aligned data is not used */
1144 #define RW_DATA(cacheline, pagealigned, inittask) \
1145 . = ALIGN(PAGE_SIZE); \
1146 .data : AT(ADDR(.data) - LOAD_OFFSET) { \
1147 INIT_TASK_DATA(inittask) \
1148 NOSAVE_DATA \
1149 PAGE_ALIGNED_DATA(pagealigned) \
1150 CACHELINE_ALIGNED_DATA(cacheline) \
1151 READ_MOSTLY_DATA(cacheline) \
1152 DATA_DATA \
1153 CONSTRUCTORS \
1154 } \
1155 BUG_TABLE \
1157 #define INIT_TEXT_SECTION(inittext_align) \
1158 . = ALIGN(inittext_align); \
1159 .init.text : AT(ADDR(.init.text) - LOAD_OFFSET) { \
1160 _sinittext = .; \
1161 INIT_TEXT \
1162 _einittext = .; \
1163 }
1165 #define INIT_DATA_SECTION(initsetup_align) \
1166 .init.data : AT(ADDR(.init.data) - LOAD_OFFSET) { \
1167 INIT_DATA \
1168 INIT_SETUP(initsetup_align) \
1169 INIT_CALLS \
1170 CON_INITCALL \
1171 INIT_RAM_FS \
1172 }
1174 #define BSS_SECTION(sbss_align, bss_align, stop_align) \
1175 . = ALIGN(sbss_align); \
1176 __bss_start = .; \
1177 SBSS(sbss_align) \
1178 BSS(bss_align) \
1179 . = ALIGN(stop_align); \
1180 __bss_stop = .;