xref: /linux/arch/arm64/kernel/vmlinux.lds.S (revision 0e685c3e7158d35626d6d76b9f859eae806d87fa)
1/* SPDX-License-Identifier: GPL-2.0 */
2/*
3 * ld script to make ARM Linux kernel
4 * taken from the i386 version by Russell King
5 * Written by Martin Mares <mj@atrey.karlin.mff.cuni.cz>
6 */
7
8#include <asm/hyp_image.h>
9#ifdef CONFIG_KVM
10#define HYPERVISOR_EXTABLE					\
11	. = ALIGN(SZ_8);					\
12	__start___kvm_ex_table = .;				\
13	*(__kvm_ex_table)					\
14	__stop___kvm_ex_table = .;
15
16#define HYPERVISOR_DATA_SECTIONS				\
17	HYP_SECTION_NAME(.rodata) : {				\
18		. = ALIGN(PAGE_SIZE);				\
19		__hyp_rodata_start = .;				\
20		*(HYP_SECTION_NAME(.data..ro_after_init))	\
21		*(HYP_SECTION_NAME(.rodata))			\
22		. = ALIGN(PAGE_SIZE);				\
23		__hyp_rodata_end = .;				\
24	}
25
26#define HYPERVISOR_PERCPU_SECTION				\
27	. = ALIGN(PAGE_SIZE);					\
28	HYP_SECTION_NAME(.data..percpu) : {			\
29		*(HYP_SECTION_NAME(.data..percpu))		\
30	}
31
32#define HYPERVISOR_RELOC_SECTION				\
33	.hyp.reloc : ALIGN(4) {					\
34		__hyp_reloc_begin = .;				\
35		*(.hyp.reloc)					\
36		__hyp_reloc_end = .;				\
37	}
38
39#define BSS_FIRST_SECTIONS					\
40	__hyp_bss_start = .;					\
41	*(HYP_SECTION_NAME(.bss))				\
42	. = ALIGN(PAGE_SIZE);					\
43	__hyp_bss_end = .;
44
45/*
46 * We require that __hyp_bss_start and __bss_start are aligned, and enforce it
47 * with an assertion. But the BSS_SECTION macro places an empty .sbss section
48 * between them, which can in some cases cause the linker to misalign them. To
49 * work around the issue, force a page alignment for __bss_start.
50 */
51#define SBSS_ALIGN			PAGE_SIZE
52#else /* CONFIG_KVM */
53#define HYPERVISOR_EXTABLE
54#define HYPERVISOR_DATA_SECTIONS
55#define HYPERVISOR_PERCPU_SECTION
56#define HYPERVISOR_RELOC_SECTION
57#define SBSS_ALIGN			0
58#endif
59
60#define RO_EXCEPTION_TABLE_ALIGN	4
61#define RUNTIME_DISCARD_EXIT
62
63#include <asm-generic/vmlinux.lds.h>
64#include <asm/cache.h>
65#include <asm/kernel-pgtable.h>
66#include <asm/kexec.h>
67#include <asm/memory.h>
68#include <asm/page.h>
69
70#include "image.h"
71
72OUTPUT_ARCH(aarch64)
73ENTRY(_text)
74
75jiffies = jiffies_64;
76
77#define HYPERVISOR_TEXT					\
78	. = ALIGN(PAGE_SIZE);				\
79	__hyp_idmap_text_start = .;			\
80	*(.hyp.idmap.text)				\
81	__hyp_idmap_text_end = .;			\
82	__hyp_text_start = .;				\
83	*(.hyp.text)					\
84	HYPERVISOR_EXTABLE				\
85	. = ALIGN(PAGE_SIZE);				\
86	__hyp_text_end = .;
87
88#define IDMAP_TEXT					\
89	. = ALIGN(SZ_4K);				\
90	__idmap_text_start = .;				\
91	*(.idmap.text)					\
92	__idmap_text_end = .;
93
94#ifdef CONFIG_HIBERNATION
95#define HIBERNATE_TEXT					\
96	ALIGN_FUNCTION();				\
97	__hibernate_exit_text_start = .;		\
98	*(.hibernate_exit.text)				\
99	__hibernate_exit_text_end = .;
100#else
101#define HIBERNATE_TEXT
102#endif
103
104#ifdef CONFIG_KEXEC_CORE
105#define KEXEC_TEXT					\
106	ALIGN_FUNCTION();				\
107	__relocate_new_kernel_start = .;		\
108	*(.kexec_relocate.text)				\
109	__relocate_new_kernel_end = .;
110#else
111#define KEXEC_TEXT
112#endif
113
114#ifdef CONFIG_UNMAP_KERNEL_AT_EL0
115#define TRAMP_TEXT					\
116	. = ALIGN(PAGE_SIZE);				\
117	__entry_tramp_text_start = .;			\
118	*(.entry.tramp.text)				\
119	. = ALIGN(PAGE_SIZE);				\
120	__entry_tramp_text_end = .;			\
121	*(.entry.tramp.rodata)
122#else
123#define TRAMP_TEXT
124#endif
125
126#ifdef CONFIG_UNWIND_TABLES
127#define UNWIND_DATA_SECTIONS				\
128	.eh_frame : {					\
129		__eh_frame_start = .;			\
130		*(.eh_frame)				\
131		__eh_frame_end = .;			\
132	}
133#else
134#define UNWIND_DATA_SECTIONS
135#endif
136
137/*
138 * The size of the PE/COFF section that covers the kernel image, which
139 * runs from _stext to _edata, must be a round multiple of the PE/COFF
140 * FileAlignment, which we set to its minimum value of 0x200. '_stext'
141 * itself is 4 KB aligned, so padding out _edata to a 0x200 aligned
142 * boundary should be sufficient.
143 */
144PECOFF_FILE_ALIGNMENT = 0x200;
145
146#ifdef CONFIG_EFI
147#define PECOFF_EDATA_PADDING	\
148	.pecoff_edata_padding : { BYTE(0); . = ALIGN(PECOFF_FILE_ALIGNMENT); }
149#else
150#define PECOFF_EDATA_PADDING
151#endif
152
153SECTIONS
154{
155	/*
156	 * XXX: The linker does not define how output sections are
157	 * assigned to input sections when there are multiple statements
158	 * matching the same input section name.  There is no documented
159	 * order of matching.
160	 */
161	DISCARDS
162	/DISCARD/ : {
163		*(.interp .dynamic)
164		*(.dynsym .dynstr .hash .gnu.hash)
165	}
166
167	. = KIMAGE_VADDR;
168
169	.head.text : {
170		_text = .;
171		HEAD_TEXT
172	}
173	.text : ALIGN(SEGMENT_ALIGN) {	/* Real text segment		*/
174		_stext = .;		/* Text and read-only data	*/
175			IRQENTRY_TEXT
176			SOFTIRQENTRY_TEXT
177			ENTRY_TEXT
178			TEXT_TEXT
179			SCHED_TEXT
180			LOCK_TEXT
181			KPROBES_TEXT
182			HYPERVISOR_TEXT
183			*(.gnu.warning)
184		. = ALIGN(16);
185		*(.got)			/* Global offset table		*/
186	}
187
188	/*
189	 * Make sure that the .got.plt is either completely empty or it
190	 * contains only the lazy dispatch entries.
191	 */
192	.got.plt : { *(.got.plt) }
193	ASSERT(SIZEOF(.got.plt) == 0 || SIZEOF(.got.plt) == 0x18,
194	       "Unexpected GOT/PLT entries detected!")
195
196	. = ALIGN(SEGMENT_ALIGN);
197	_etext = .;			/* End of text section */
198
199	/* everything from this point to __init_begin will be marked RO NX */
200	RO_DATA(PAGE_SIZE)
201
202	HYPERVISOR_DATA_SECTIONS
203
204	/* code sections that are never executed via the kernel mapping */
205	.rodata.text : {
206		TRAMP_TEXT
207		HIBERNATE_TEXT
208		KEXEC_TEXT
209		IDMAP_TEXT
210		. = ALIGN(PAGE_SIZE);
211	}
212
213	idmap_pg_dir = .;
214	. += PAGE_SIZE;
215
216#ifdef CONFIG_UNMAP_KERNEL_AT_EL0
217	tramp_pg_dir = .;
218	. += PAGE_SIZE;
219#endif
220
221	reserved_pg_dir = .;
222	. += PAGE_SIZE;
223
224	swapper_pg_dir = .;
225	. += PAGE_SIZE;
226
227	. = ALIGN(SEGMENT_ALIGN);
228	__init_begin = .;
229	__inittext_begin = .;
230
231	INIT_TEXT_SECTION(8)
232
233	__exittext_begin = .;
234	.exit.text : {
235		EXIT_TEXT
236	}
237	__exittext_end = .;
238
239	. = ALIGN(4);
240	.altinstructions : {
241		__alt_instructions = .;
242		*(.altinstructions)
243		__alt_instructions_end = .;
244	}
245
246	UNWIND_DATA_SECTIONS
247
248	. = ALIGN(SEGMENT_ALIGN);
249	__inittext_end = .;
250	__initdata_begin = .;
251
252	init_idmap_pg_dir = .;
253	. += INIT_IDMAP_DIR_SIZE;
254	init_idmap_pg_end = .;
255
256	.init.data : {
257		INIT_DATA
258		INIT_SETUP(16)
259		INIT_CALLS
260		CON_INITCALL
261		INIT_RAM_FS
262		*(.init.altinstructions .init.bss)	/* from the EFI stub */
263	}
264	.exit.data : {
265		EXIT_DATA
266	}
267
268	PERCPU_SECTION(L1_CACHE_BYTES)
269	HYPERVISOR_PERCPU_SECTION
270
271	HYPERVISOR_RELOC_SECTION
272
273	.rela.dyn : ALIGN(8) {
274		__rela_start = .;
275		*(.rela .rela*)
276		__rela_end = .;
277	}
278
279	.relr.dyn : ALIGN(8) {
280		__relr_start = .;
281		*(.relr.dyn)
282		__relr_end = .;
283	}
284
285	. = ALIGN(SEGMENT_ALIGN);
286	__initdata_end = .;
287	__init_end = .;
288
289	_data = .;
290	_sdata = .;
291	RW_DATA(L1_CACHE_BYTES, PAGE_SIZE, THREAD_ALIGN)
292
293	/*
294	 * Data written with the MMU off but read with the MMU on requires
295	 * cache lines to be invalidated, discarding up to a Cache Writeback
296	 * Granule (CWG) of data from the cache. Keep the section that
297	 * requires this type of maintenance to be in its own Cache Writeback
298	 * Granule (CWG) area so the cache maintenance operations don't
299	 * interfere with adjacent data.
300	 */
301	.mmuoff.data.write : ALIGN(SZ_2K) {
302		__mmuoff_data_start = .;
303		*(.mmuoff.data.write)
304	}
305	. = ALIGN(SZ_2K);
306	.mmuoff.data.read : {
307		*(.mmuoff.data.read)
308		__mmuoff_data_end = .;
309	}
310
311	PECOFF_EDATA_PADDING
312	__pecoff_data_rawsize = ABSOLUTE(. - __initdata_begin);
313	_edata = .;
314
315	BSS_SECTION(SBSS_ALIGN, 0, 0)
316
317	. = ALIGN(PAGE_SIZE);
318	init_pg_dir = .;
319	. += INIT_DIR_SIZE;
320	init_pg_end = .;
321
322	. = ALIGN(SEGMENT_ALIGN);
323	__pecoff_data_size = ABSOLUTE(. - __initdata_begin);
324	_end = .;
325
326	STABS_DEBUG
327	DWARF_DEBUG
328	ELF_DETAILS
329
330	HEAD_SYMBOLS
331
332	/*
333	 * Sections that should stay zero sized, which is safer to
334	 * explicitly check instead of blindly discarding.
335	 */
336	.plt : {
337		*(.plt) *(.plt.*) *(.iplt) *(.igot .igot.plt)
338	}
339	ASSERT(SIZEOF(.plt) == 0, "Unexpected run-time procedure linkages detected!")
340
341	.data.rel.ro : { *(.data.rel.ro) }
342	ASSERT(SIZEOF(.data.rel.ro) == 0, "Unexpected RELRO detected!")
343}
344
345#include "image-vars.h"
346
347/*
348 * The HYP init code and ID map text can't be longer than a page each. The
349 * former is page-aligned, but the latter may not be with 16K or 64K pages, so
350 * it should also not cross a page boundary.
351 */
352ASSERT(__hyp_idmap_text_end - __hyp_idmap_text_start <= PAGE_SIZE,
353	"HYP init code too big")
354ASSERT(__idmap_text_end - (__idmap_text_start & ~(SZ_4K - 1)) <= SZ_4K,
355	"ID map text too big or misaligned")
356#ifdef CONFIG_HIBERNATION
357ASSERT(__hibernate_exit_text_end - __hibernate_exit_text_start <= SZ_4K,
358       "Hibernate exit text is bigger than 4 KiB")
359ASSERT(__hibernate_exit_text_start == swsusp_arch_suspend_exit,
360       "Hibernate exit text does not start with swsusp_arch_suspend_exit")
361#endif
362#ifdef CONFIG_UNMAP_KERNEL_AT_EL0
363ASSERT((__entry_tramp_text_end - __entry_tramp_text_start) <= 3*PAGE_SIZE,
364	"Entry trampoline text too big")
365#endif
366#ifdef CONFIG_KVM
367ASSERT(__hyp_bss_start == __bss_start, "HYP and Host BSS are misaligned")
368#endif
369/*
370 * If padding is applied before .head.text, virt<->phys conversions will fail.
371 */
372ASSERT(_text == KIMAGE_VADDR, "HEAD is misaligned")
373
374ASSERT(swapper_pg_dir - reserved_pg_dir == RESERVED_SWAPPER_OFFSET,
375       "RESERVED_SWAPPER_OFFSET is wrong!")
376
377#ifdef CONFIG_UNMAP_KERNEL_AT_EL0
378ASSERT(swapper_pg_dir - tramp_pg_dir == TRAMP_SWAPPER_OFFSET,
379       "TRAMP_SWAPPER_OFFSET is wrong!")
380#endif
381
382#ifdef CONFIG_KEXEC_CORE
383/* kexec relocation code should fit into one KEXEC_CONTROL_PAGE_SIZE */
384ASSERT(__relocate_new_kernel_end - __relocate_new_kernel_start <= SZ_4K,
385       "kexec relocation code is bigger than 4 KiB")
386ASSERT(KEXEC_CONTROL_PAGE_SIZE >= SZ_4K, "KEXEC_CONTROL_PAGE_SIZE is broken")
387ASSERT(__relocate_new_kernel_start == arm64_relocate_new_kernel,
388       "kexec control page does not start with arm64_relocate_new_kernel")
389#endif
390