xref: /openbmc/linux/arch/arm64/kernel/vmlinux.lds.S (revision f71a261a)
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	__hibernate_exit_text_start = .;		\
97	*(.hibernate_exit.text)				\
98	__hibernate_exit_text_end = .;
99#else
100#define HIBERNATE_TEXT
101#endif
102
103#ifdef CONFIG_KEXEC_CORE
104#define KEXEC_TEXT					\
105	__relocate_new_kernel_start = .;		\
106	*(.kexec_relocate.text)				\
107	__relocate_new_kernel_end = .;
108#else
109#define KEXEC_TEXT
110#endif
111
112#ifdef CONFIG_UNMAP_KERNEL_AT_EL0
113#define TRAMP_TEXT					\
114	. = ALIGN(PAGE_SIZE);				\
115	__entry_tramp_text_start = .;			\
116	*(.entry.tramp.text)				\
117	. = ALIGN(PAGE_SIZE);				\
118	__entry_tramp_text_end = .;
119#else
120#define TRAMP_TEXT
121#endif
122
123/*
124 * The size of the PE/COFF section that covers the kernel image, which
125 * runs from _stext to _edata, must be a round multiple of the PE/COFF
126 * FileAlignment, which we set to its minimum value of 0x200. '_stext'
127 * itself is 4 KB aligned, so padding out _edata to a 0x200 aligned
128 * boundary should be sufficient.
129 */
130PECOFF_FILE_ALIGNMENT = 0x200;
131
132#ifdef CONFIG_EFI
133#define PECOFF_EDATA_PADDING	\
134	.pecoff_edata_padding : { BYTE(0); . = ALIGN(PECOFF_FILE_ALIGNMENT); }
135#else
136#define PECOFF_EDATA_PADDING
137#endif
138
139SECTIONS
140{
141	/*
142	 * XXX: The linker does not define how output sections are
143	 * assigned to input sections when there are multiple statements
144	 * matching the same input section name.  There is no documented
145	 * order of matching.
146	 */
147	DISCARDS
148	/DISCARD/ : {
149		*(.interp .dynamic)
150		*(.dynsym .dynstr .hash .gnu.hash)
151	}
152
153	. = KIMAGE_VADDR;
154
155	.head.text : {
156		_text = .;
157		HEAD_TEXT
158	}
159	.text : ALIGN(SEGMENT_ALIGN) {	/* Real text segment		*/
160		_stext = .;		/* Text and read-only data	*/
161			IRQENTRY_TEXT
162			SOFTIRQENTRY_TEXT
163			ENTRY_TEXT
164			TEXT_TEXT
165			SCHED_TEXT
166			CPUIDLE_TEXT
167			LOCK_TEXT
168			KPROBES_TEXT
169			HYPERVISOR_TEXT
170			IDMAP_TEXT
171			*(.gnu.warning)
172		. = ALIGN(16);
173		*(.got)			/* Global offset table		*/
174	}
175
176	/*
177	 * Make sure that the .got.plt is either completely empty or it
178	 * contains only the lazy dispatch entries.
179	 */
180	.got.plt : { *(.got.plt) }
181	ASSERT(SIZEOF(.got.plt) == 0 || SIZEOF(.got.plt) == 0x18,
182	       "Unexpected GOT/PLT entries detected!")
183
184	. = ALIGN(SEGMENT_ALIGN);
185	_etext = .;			/* End of text section */
186
187	/* everything from this point to __init_begin will be marked RO NX */
188	RO_DATA(PAGE_SIZE)
189
190	HYPERVISOR_DATA_SECTIONS
191
192	/* code sections that are never executed via the kernel mapping */
193	.rodata.text : {
194		TRAMP_TEXT
195		HIBERNATE_TEXT
196		KEXEC_TEXT
197		. = ALIGN(PAGE_SIZE);
198	}
199
200	idmap_pg_dir = .;
201	. += IDMAP_DIR_SIZE;
202	idmap_pg_end = .;
203
204#ifdef CONFIG_UNMAP_KERNEL_AT_EL0
205	tramp_pg_dir = .;
206	. += PAGE_SIZE;
207#endif
208
209	reserved_pg_dir = .;
210	. += PAGE_SIZE;
211
212	swapper_pg_dir = .;
213	. += PAGE_SIZE;
214
215	. = ALIGN(SEGMENT_ALIGN);
216	__init_begin = .;
217	__inittext_begin = .;
218
219	INIT_TEXT_SECTION(8)
220
221	__exittext_begin = .;
222	.exit.text : {
223		EXIT_TEXT
224	}
225	__exittext_end = .;
226
227	. = ALIGN(4);
228	.altinstructions : {
229		__alt_instructions = .;
230		*(.altinstructions)
231		__alt_instructions_end = .;
232	}
233
234	. = ALIGN(SEGMENT_ALIGN);
235	__inittext_end = .;
236	__initdata_begin = .;
237
238	.init.data : {
239		INIT_DATA
240		INIT_SETUP(16)
241		INIT_CALLS
242		CON_INITCALL
243		INIT_RAM_FS
244		*(.init.altinstructions .init.bss)	/* from the EFI stub */
245	}
246	.exit.data : {
247		EXIT_DATA
248	}
249
250	PERCPU_SECTION(L1_CACHE_BYTES)
251	HYPERVISOR_PERCPU_SECTION
252
253	HYPERVISOR_RELOC_SECTION
254
255	.rela.dyn : ALIGN(8) {
256		*(.rela .rela*)
257	}
258
259	__rela_offset	= ABSOLUTE(ADDR(.rela.dyn) - KIMAGE_VADDR);
260	__rela_size	= SIZEOF(.rela.dyn);
261
262#ifdef CONFIG_RELR
263	.relr.dyn : ALIGN(8) {
264		*(.relr.dyn)
265	}
266
267	__relr_offset	= ABSOLUTE(ADDR(.relr.dyn) - KIMAGE_VADDR);
268	__relr_size	= SIZEOF(.relr.dyn);
269#endif
270
271	. = ALIGN(SEGMENT_ALIGN);
272	__initdata_end = .;
273	__init_end = .;
274
275	_data = .;
276	_sdata = .;
277	RW_DATA(L1_CACHE_BYTES, PAGE_SIZE, THREAD_ALIGN)
278
279	/*
280	 * Data written with the MMU off but read with the MMU on requires
281	 * cache lines to be invalidated, discarding up to a Cache Writeback
282	 * Granule (CWG) of data from the cache. Keep the section that
283	 * requires this type of maintenance to be in its own Cache Writeback
284	 * Granule (CWG) area so the cache maintenance operations don't
285	 * interfere with adjacent data.
286	 */
287	.mmuoff.data.write : ALIGN(SZ_2K) {
288		__mmuoff_data_start = .;
289		*(.mmuoff.data.write)
290	}
291	. = ALIGN(SZ_2K);
292	.mmuoff.data.read : {
293		*(.mmuoff.data.read)
294		__mmuoff_data_end = .;
295	}
296
297	PECOFF_EDATA_PADDING
298	__pecoff_data_rawsize = ABSOLUTE(. - __initdata_begin);
299	_edata = .;
300
301	BSS_SECTION(SBSS_ALIGN, 0, 0)
302
303	. = ALIGN(PAGE_SIZE);
304	init_pg_dir = .;
305	. += INIT_DIR_SIZE;
306	init_pg_end = .;
307
308	. = ALIGN(SEGMENT_ALIGN);
309	__pecoff_data_size = ABSOLUTE(. - __initdata_begin);
310	_end = .;
311
312	STABS_DEBUG
313	DWARF_DEBUG
314	ELF_DETAILS
315
316	HEAD_SYMBOLS
317
318	/*
319	 * Sections that should stay zero sized, which is safer to
320	 * explicitly check instead of blindly discarding.
321	 */
322	.plt : {
323		*(.plt) *(.plt.*) *(.iplt) *(.igot .igot.plt)
324	}
325	ASSERT(SIZEOF(.plt) == 0, "Unexpected run-time procedure linkages detected!")
326
327	.data.rel.ro : { *(.data.rel.ro) }
328	ASSERT(SIZEOF(.data.rel.ro) == 0, "Unexpected RELRO detected!")
329}
330
331#include "image-vars.h"
332
333/*
334 * The HYP init code and ID map text can't be longer than a page each. The
335 * former is page-aligned, but the latter may not be with 16K or 64K pages, so
336 * it should also not cross a page boundary.
337 */
338ASSERT(__hyp_idmap_text_end - __hyp_idmap_text_start <= PAGE_SIZE,
339	"HYP init code too big")
340ASSERT(__idmap_text_end - (__idmap_text_start & ~(SZ_4K - 1)) <= SZ_4K,
341	"ID map text too big or misaligned")
342#ifdef CONFIG_HIBERNATION
343ASSERT(__hibernate_exit_text_end - __hibernate_exit_text_start <= SZ_4K,
344       "Hibernate exit text is bigger than 4 KiB")
345#endif
346#ifdef CONFIG_UNMAP_KERNEL_AT_EL0
347ASSERT((__entry_tramp_text_end - __entry_tramp_text_start) <= 3*PAGE_SIZE,
348	"Entry trampoline text too big")
349#endif
350#ifdef CONFIG_KVM
351ASSERT(__hyp_bss_start == __bss_start, "HYP and Host BSS are misaligned")
352#endif
353/*
354 * If padding is applied before .head.text, virt<->phys conversions will fail.
355 */
356ASSERT(_text == KIMAGE_VADDR, "HEAD is misaligned")
357
358ASSERT(swapper_pg_dir - reserved_pg_dir == RESERVED_SWAPPER_OFFSET,
359       "RESERVED_SWAPPER_OFFSET is wrong!")
360
361#ifdef CONFIG_UNMAP_KERNEL_AT_EL0
362ASSERT(swapper_pg_dir - tramp_pg_dir == TRAMP_SWAPPER_OFFSET,
363       "TRAMP_SWAPPER_OFFSET is wrong!")
364#endif
365
366#ifdef CONFIG_KEXEC_CORE
367/* kexec relocation code should fit into one KEXEC_CONTROL_PAGE_SIZE */
368ASSERT(__relocate_new_kernel_end - __relocate_new_kernel_start <= SZ_4K,
369       "kexec relocation code is bigger than 4 KiB")
370ASSERT(KEXEC_CONTROL_PAGE_SIZE >= SZ_4K, "KEXEC_CONTROL_PAGE_SIZE is broken")
371#endif
372