xref: /openbmc/linux/arch/x86/kernel/vmlinux.lds.S (revision fd589a8f) 
1/*
2 * ld script for the x86 kernel
3 *
4 * Historic 32-bit version written by Martin Mares <mj@atrey.karlin.mff.cuni.cz>
5 *
6 * Modernisation, unification and other changes and fixes:
7 *   Copyright (C) 2007-2009  Sam Ravnborg <sam@ravnborg.org>
8 *
9 *
10 * Don't define absolute symbols until and unless you know that symbol
11 * value is should remain constant even if kernel image is relocated
12 * at run time. Absolute symbols are not relocated. If symbol value should
13 * change if kernel is relocated, make the symbol section relative and
14 * put it inside the section definition.
15 */
16
17#ifdef CONFIG_X86_32
18#define LOAD_OFFSET __PAGE_OFFSET
19#else
20#define LOAD_OFFSET __START_KERNEL_map
21#endif
22
23#include <asm-generic/vmlinux.lds.h>
24#include <asm/asm-offsets.h>
25#include <asm/thread_info.h>
26#include <asm/page_types.h>
27#include <asm/cache.h>
28#include <asm/boot.h>
29
30#undef i386     /* in case the preprocessor is a 32bit one */
31
32OUTPUT_FORMAT(CONFIG_OUTPUT_FORMAT, CONFIG_OUTPUT_FORMAT, CONFIG_OUTPUT_FORMAT)
33
34#ifdef CONFIG_X86_32
35OUTPUT_ARCH(i386)
36ENTRY(phys_startup_32)
37jiffies = jiffies_64;
38#else
39OUTPUT_ARCH(i386:x86-64)
40ENTRY(phys_startup_64)
41jiffies_64 = jiffies;
42#endif
43
44PHDRS {
45	text PT_LOAD FLAGS(5);          /* R_E */
46	data PT_LOAD FLAGS(7);          /* RWE */
47#ifdef CONFIG_X86_64
48	user PT_LOAD FLAGS(7);          /* RWE */
49#ifdef CONFIG_SMP
50	percpu PT_LOAD FLAGS(7);        /* RWE */
51#endif
52	init PT_LOAD FLAGS(7);          /* RWE */
53#endif
54	note PT_NOTE FLAGS(0);          /* ___ */
55}
56
57SECTIONS
58{
59#ifdef CONFIG_X86_32
60        . = LOAD_OFFSET + LOAD_PHYSICAL_ADDR;
61        phys_startup_32 = startup_32 - LOAD_OFFSET;
62#else
63        . = __START_KERNEL;
64        phys_startup_64 = startup_64 - LOAD_OFFSET;
65#endif
66
67	/* Text and read-only data */
68
69	/* bootstrapping code */
70	.text.head : AT(ADDR(.text.head) - LOAD_OFFSET) {
71		_text = .;
72		*(.text.head)
73	} :text = 0x9090
74
75	/* The rest of the text */
76	.text :  AT(ADDR(.text) - LOAD_OFFSET) {
77#ifdef CONFIG_X86_32
78		/* not really needed, already page aligned */
79		. = ALIGN(PAGE_SIZE);
80		*(.text.page_aligned)
81#endif
82		. = ALIGN(8);
83		_stext = .;
84		TEXT_TEXT
85		SCHED_TEXT
86		LOCK_TEXT
87		KPROBES_TEXT
88		IRQENTRY_TEXT
89		*(.fixup)
90		*(.gnu.warning)
91		/* End of text section */
92		_etext = .;
93	} :text = 0x9090
94
95	NOTES :text :note
96
97	/* Exception table */
98	. = ALIGN(16);
99	__ex_table : AT(ADDR(__ex_table) - LOAD_OFFSET) {
100		__start___ex_table = .;
101		*(__ex_table)
102		__stop___ex_table = .;
103	} :text = 0x9090
104
105	RO_DATA(PAGE_SIZE)
106
107	/* Data */
108	.data : AT(ADDR(.data) - LOAD_OFFSET) {
109		/* Start of data section */
110		_sdata = .;
111
112		/* init_task */
113		INIT_TASK_DATA(THREAD_SIZE)
114
115#ifdef CONFIG_X86_32
116		/* 32 bit has nosave before _edata */
117		NOSAVE_DATA
118#endif
119
120		PAGE_ALIGNED_DATA(PAGE_SIZE)
121		*(.data.idt)
122
123		CACHELINE_ALIGNED_DATA(CONFIG_X86_L1_CACHE_BYTES)
124
125		DATA_DATA
126		CONSTRUCTORS
127
128		/* rarely changed data like cpu maps */
129		READ_MOSTLY_DATA(CONFIG_X86_INTERNODE_CACHE_BYTES)
130
131		/* End of data section */
132		_edata = .;
133	} :data
134
135#ifdef CONFIG_X86_64
136
137#define VSYSCALL_ADDR (-10*1024*1024)
138#define VSYSCALL_PHYS_ADDR ((LOADADDR(.data) + SIZEOF(.data) + \
139                            PAGE_SIZE - 1) & ~(PAGE_SIZE - 1))
140#define VSYSCALL_VIRT_ADDR ((ADDR(.data) + SIZEOF(.data) + \
141                            PAGE_SIZE - 1) & ~(PAGE_SIZE - 1))
142
143#define VLOAD_OFFSET (VSYSCALL_ADDR - VSYSCALL_PHYS_ADDR)
144#define VLOAD(x) (ADDR(x) - VLOAD_OFFSET)
145
146#define VVIRT_OFFSET (VSYSCALL_ADDR - VSYSCALL_VIRT_ADDR)
147#define VVIRT(x) (ADDR(x) - VVIRT_OFFSET)
148
149	. = VSYSCALL_ADDR;
150	.vsyscall_0 : AT(VSYSCALL_PHYS_ADDR) {
151		*(.vsyscall_0)
152	} :user
153
154	__vsyscall_0 = VSYSCALL_VIRT_ADDR;
155
156	. = ALIGN(CONFIG_X86_L1_CACHE_BYTES);
157	.vsyscall_fn : AT(VLOAD(.vsyscall_fn)) {
158		*(.vsyscall_fn)
159	}
160
161	. = ALIGN(CONFIG_X86_L1_CACHE_BYTES);
162	.vsyscall_gtod_data : AT(VLOAD(.vsyscall_gtod_data)) {
163		*(.vsyscall_gtod_data)
164	}
165
166	vsyscall_gtod_data = VVIRT(.vsyscall_gtod_data);
167	.vsyscall_clock : AT(VLOAD(.vsyscall_clock)) {
168		*(.vsyscall_clock)
169	}
170	vsyscall_clock = VVIRT(.vsyscall_clock);
171
172
173	.vsyscall_1 ADDR(.vsyscall_0) + 1024: AT(VLOAD(.vsyscall_1)) {
174		*(.vsyscall_1)
175	}
176	.vsyscall_2 ADDR(.vsyscall_0) + 2048: AT(VLOAD(.vsyscall_2)) {
177		*(.vsyscall_2)
178	}
179
180	.vgetcpu_mode : AT(VLOAD(.vgetcpu_mode)) {
181		*(.vgetcpu_mode)
182	}
183	vgetcpu_mode = VVIRT(.vgetcpu_mode);
184
185	. = ALIGN(CONFIG_X86_L1_CACHE_BYTES);
186	.jiffies : AT(VLOAD(.jiffies)) {
187		*(.jiffies)
188	}
189	jiffies = VVIRT(.jiffies);
190
191	.vsyscall_3 ADDR(.vsyscall_0) + 3072: AT(VLOAD(.vsyscall_3)) {
192		*(.vsyscall_3)
193	}
194
195	. = VSYSCALL_VIRT_ADDR + PAGE_SIZE;
196
197#undef VSYSCALL_ADDR
198#undef VSYSCALL_PHYS_ADDR
199#undef VSYSCALL_VIRT_ADDR
200#undef VLOAD_OFFSET
201#undef VLOAD
202#undef VVIRT_OFFSET
203#undef VVIRT
204
205#endif /* CONFIG_X86_64 */
206
207	/* Init code and data - will be freed after init */
208	. = ALIGN(PAGE_SIZE);
209	.init.begin : AT(ADDR(.init.begin) - LOAD_OFFSET) {
210		__init_begin = .; /* paired with __init_end */
211	}
212
213#if defined(CONFIG_X86_64) && defined(CONFIG_SMP)
214	/*
215	 * percpu offsets are zero-based on SMP.  PERCPU_VADDR() changes the
216	 * output PHDR, so the next output section - .init.text - should
217	 * start another segment - init.
218	 */
219	PERCPU_VADDR(0, :percpu)
220#endif
221
222	.init.text : AT(ADDR(.init.text) - LOAD_OFFSET) {
223		_sinittext = .;
224		INIT_TEXT
225		_einittext = .;
226	}
227#ifdef CONFIG_X86_64
228	:init
229#endif
230
231	.init.data : AT(ADDR(.init.data) - LOAD_OFFSET) {
232		INIT_DATA
233	}
234
235	. = ALIGN(16);
236	.init.setup : AT(ADDR(.init.setup) - LOAD_OFFSET) {
237		__setup_start = .;
238		*(.init.setup)
239		__setup_end = .;
240	}
241	.initcall.init : AT(ADDR(.initcall.init) - LOAD_OFFSET) {
242		__initcall_start = .;
243		INITCALLS
244		__initcall_end = .;
245	}
246
247	.con_initcall.init : AT(ADDR(.con_initcall.init) - LOAD_OFFSET) {
248		__con_initcall_start = .;
249		*(.con_initcall.init)
250		__con_initcall_end = .;
251	}
252
253	.x86_cpu_dev.init : AT(ADDR(.x86_cpu_dev.init) - LOAD_OFFSET) {
254		__x86_cpu_dev_start = .;
255		*(.x86_cpu_dev.init)
256		__x86_cpu_dev_end = .;
257	}
258
259	SECURITY_INIT
260
261	. = ALIGN(8);
262	.parainstructions : AT(ADDR(.parainstructions) - LOAD_OFFSET) {
263		__parainstructions = .;
264		*(.parainstructions)
265		__parainstructions_end = .;
266	}
267
268	. = ALIGN(8);
269	.altinstructions : AT(ADDR(.altinstructions) - LOAD_OFFSET) {
270		__alt_instructions = .;
271		*(.altinstructions)
272		__alt_instructions_end = .;
273	}
274
275	.altinstr_replacement : AT(ADDR(.altinstr_replacement) - LOAD_OFFSET) {
276		*(.altinstr_replacement)
277	}
278
279	/*
280	 * .exit.text is discard at runtime, not link time, to deal with
281	 *  references from .altinstructions and .eh_frame
282	 */
283	.exit.text : AT(ADDR(.exit.text) - LOAD_OFFSET) {
284		EXIT_TEXT
285	}
286
287	.exit.data : AT(ADDR(.exit.data) - LOAD_OFFSET) {
288		EXIT_DATA
289	}
290
291#ifdef CONFIG_BLK_DEV_INITRD
292	. = ALIGN(PAGE_SIZE);
293	.init.ramfs : AT(ADDR(.init.ramfs) - LOAD_OFFSET) {
294		__initramfs_start = .;
295		*(.init.ramfs)
296		__initramfs_end = .;
297	}
298#endif
299
300#if !defined(CONFIG_X86_64) || !defined(CONFIG_SMP)
301	PERCPU(PAGE_SIZE)
302#endif
303
304	. = ALIGN(PAGE_SIZE);
305
306	/* freed after init ends here */
307	.init.end : AT(ADDR(.init.end) - LOAD_OFFSET) {
308		__init_end = .;
309	}
310
311	/*
312	 * smp_locks might be freed after init
313	 * start/end must be page aligned
314	 */
315	. = ALIGN(PAGE_SIZE);
316	.smp_locks : AT(ADDR(.smp_locks) - LOAD_OFFSET) {
317		__smp_locks = .;
318		*(.smp_locks)
319		__smp_locks_end = .;
320		. = ALIGN(PAGE_SIZE);
321	}
322
323#ifdef CONFIG_X86_64
324	.data_nosave : AT(ADDR(.data_nosave) - LOAD_OFFSET) {
325		NOSAVE_DATA
326	}
327#endif
328
329	/* BSS */
330	. = ALIGN(PAGE_SIZE);
331	.bss : AT(ADDR(.bss) - LOAD_OFFSET) {
332		__bss_start = .;
333		*(.bss.page_aligned)
334		*(.bss)
335		. = ALIGN(4);
336		__bss_stop = .;
337	}
338
339	. = ALIGN(PAGE_SIZE);
340	.brk : AT(ADDR(.brk) - LOAD_OFFSET) {
341		__brk_base = .;
342		. += 64 * 1024;		/* 64k alignment slop space */
343		*(.brk_reservation)	/* areas brk users have reserved */
344		__brk_limit = .;
345	}
346
347	.end : AT(ADDR(.end) - LOAD_OFFSET) {
348		_end = .;
349	}
350
351        STABS_DEBUG
352        DWARF_DEBUG
353
354	/* Sections to be discarded */
355	DISCARDS
356	/DISCARD/ : { *(.eh_frame) }
357}
358
359
360#ifdef CONFIG_X86_32
361. = ASSERT((_end - LOAD_OFFSET <= KERNEL_IMAGE_SIZE),
362	   "kernel image bigger than KERNEL_IMAGE_SIZE");
363#else
364/*
365 * Per-cpu symbols which need to be offset from __per_cpu_load
366 * for the boot processor.
367 */
368#define INIT_PER_CPU(x) init_per_cpu__##x = per_cpu__##x + __per_cpu_load
369INIT_PER_CPU(gdt_page);
370INIT_PER_CPU(irq_stack_union);
371
372/*
373 * Build-time check on the image size:
374 */
375. = ASSERT((_end - _text <= KERNEL_IMAGE_SIZE),
376	   "kernel image bigger than KERNEL_IMAGE_SIZE");
377
378#ifdef CONFIG_SMP
379. = ASSERT((per_cpu__irq_stack_union == 0),
380           "irq_stack_union is not at start of per-cpu area");
381#endif
382
383#endif /* CONFIG_X86_32 */
384
385#ifdef CONFIG_KEXEC
386#include <asm/kexec.h>
387
388. = ASSERT(kexec_control_code_size <= KEXEC_CONTROL_CODE_MAX_SIZE,
389           "kexec control code size is too big");
390#endif
391
392