xref: /linux/arch/x86/kernel/vmlinux.lds.S (revision ac6a0cf6716bb46813d0161024c66c2af66e53d1)
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	data.init PT_LOAD FLAGS(7);     /* RWE */
50#ifdef CONFIG_SMP
51	percpu PT_LOAD FLAGS(7);        /* RWE */
52#endif
53	data.init2 PT_LOAD FLAGS(7);    /* RWE */
54#endif
55	note PT_NOTE FLAGS(0);          /* ___ */
56}
57
58SECTIONS
59{
60#ifdef CONFIG_X86_32
61        . = LOAD_OFFSET + LOAD_PHYSICAL_ADDR;
62        phys_startup_32 = startup_32 - LOAD_OFFSET;
63#else
64        . = __START_KERNEL;
65        phys_startup_64 = startup_64 - LOAD_OFFSET;
66#endif
67
68	/* Text and read-only data */
69
70	/* bootstrapping code */
71	.text.head : AT(ADDR(.text.head) - LOAD_OFFSET) {
72		_text = .;
73		*(.text.head)
74	} :text = 0x9090
75
76	/* The rest of the text */
77	.text :  AT(ADDR(.text) - LOAD_OFFSET) {
78#ifdef CONFIG_X86_32
79		/* not really needed, already page aligned */
80		. = ALIGN(PAGE_SIZE);
81		*(.text.page_aligned)
82#endif
83		. = ALIGN(8);
84		_stext = .;
85		TEXT_TEXT
86		SCHED_TEXT
87		LOCK_TEXT
88		KPROBES_TEXT
89		IRQENTRY_TEXT
90		*(.fixup)
91		*(.gnu.warning)
92		/* End of text section */
93		_etext = .;
94	} :text = 0x9090
95
96	NOTES :text :note
97
98	/* Exception table */
99	. = ALIGN(16);
100	__ex_table : AT(ADDR(__ex_table) - LOAD_OFFSET) {
101		__start___ex_table = .;
102		*(__ex_table)
103		__stop___ex_table = .;
104	} :text = 0x9090
105
106	RODATA
107
108	/* Data */
109	. = ALIGN(PAGE_SIZE);
110	.data : AT(ADDR(.data) - LOAD_OFFSET) {
111		/* Start of data section */
112		_sdata = .;
113		DATA_DATA
114		CONSTRUCTORS
115	} :data
116
117#ifdef CONFIG_X86_32
118	/* 32 bit has nosave before _edata */
119	. = ALIGN(PAGE_SIZE);
120	.data_nosave : AT(ADDR(.data_nosave) - LOAD_OFFSET) {
121		__nosave_begin = .;
122		*(.data.nosave)
123		. = ALIGN(PAGE_SIZE);
124		__nosave_end = .;
125	}
126#endif
127
128	. = ALIGN(PAGE_SIZE);
129	.data.page_aligned : AT(ADDR(.data.page_aligned) - LOAD_OFFSET) {
130		*(.data.page_aligned)
131		*(.data.idt)
132	}
133
134#ifdef CONFIG_X86_32
135	. = ALIGN(32);
136#else
137	. = ALIGN(PAGE_SIZE);
138	. = ALIGN(CONFIG_X86_L1_CACHE_BYTES);
139#endif
140	.data.cacheline_aligned :
141		AT(ADDR(.data.cacheline_aligned) - LOAD_OFFSET) {
142		*(.data.cacheline_aligned)
143	}
144
145	/* rarely changed data like cpu maps */
146#ifdef CONFIG_X86_32
147	. = ALIGN(32);
148#else
149	. = ALIGN(CONFIG_X86_INTERNODE_CACHE_BYTES);
150#endif
151	.data.read_mostly : AT(ADDR(.data.read_mostly) - LOAD_OFFSET) {
152		*(.data.read_mostly)
153
154		/* End of data section */
155		_edata = .;
156	}
157
158#ifdef CONFIG_X86_64
159
160#define VSYSCALL_ADDR (-10*1024*1024)
161#define VSYSCALL_PHYS_ADDR ((LOADADDR(.data.read_mostly) + \
162                            SIZEOF(.data.read_mostly) + 4095) & ~(4095))
163#define VSYSCALL_VIRT_ADDR ((ADDR(.data.read_mostly) + \
164                            SIZEOF(.data.read_mostly) + 4095) & ~(4095))
165
166#define VLOAD_OFFSET (VSYSCALL_ADDR - VSYSCALL_PHYS_ADDR)
167#define VLOAD(x) (ADDR(x) - VLOAD_OFFSET)
168
169#define VVIRT_OFFSET (VSYSCALL_ADDR - VSYSCALL_VIRT_ADDR)
170#define VVIRT(x) (ADDR(x) - VVIRT_OFFSET)
171
172	. = VSYSCALL_ADDR;
173	.vsyscall_0 : AT(VSYSCALL_PHYS_ADDR) {
174		*(.vsyscall_0)
175	} :user
176
177	__vsyscall_0 = VSYSCALL_VIRT_ADDR;
178
179	. = ALIGN(CONFIG_X86_L1_CACHE_BYTES);
180	.vsyscall_fn : AT(VLOAD(.vsyscall_fn)) {
181		*(.vsyscall_fn)
182	}
183
184	. = ALIGN(CONFIG_X86_L1_CACHE_BYTES);
185	.vsyscall_gtod_data : AT(VLOAD(.vsyscall_gtod_data)) {
186		*(.vsyscall_gtod_data)
187	}
188
189	vsyscall_gtod_data = VVIRT(.vsyscall_gtod_data);
190	.vsyscall_clock : AT(VLOAD(.vsyscall_clock)) {
191		*(.vsyscall_clock)
192	}
193	vsyscall_clock = VVIRT(.vsyscall_clock);
194
195
196	.vsyscall_1 ADDR(.vsyscall_0) + 1024: AT(VLOAD(.vsyscall_1)) {
197		*(.vsyscall_1)
198	}
199	.vsyscall_2 ADDR(.vsyscall_0) + 2048: AT(VLOAD(.vsyscall_2)) {
200		*(.vsyscall_2)
201	}
202
203	.vgetcpu_mode : AT(VLOAD(.vgetcpu_mode)) {
204		*(.vgetcpu_mode)
205	}
206	vgetcpu_mode = VVIRT(.vgetcpu_mode);
207
208	. = ALIGN(CONFIG_X86_L1_CACHE_BYTES);
209	.jiffies : AT(VLOAD(.jiffies)) {
210		*(.jiffies)
211	}
212	jiffies = VVIRT(.jiffies);
213
214	.vsyscall_3 ADDR(.vsyscall_0) + 3072: AT(VLOAD(.vsyscall_3)) {
215		*(.vsyscall_3)
216	}
217
218	. = VSYSCALL_VIRT_ADDR + PAGE_SIZE;
219
220#undef VSYSCALL_ADDR
221#undef VSYSCALL_PHYS_ADDR
222#undef VSYSCALL_VIRT_ADDR
223#undef VLOAD_OFFSET
224#undef VLOAD
225#undef VVIRT_OFFSET
226#undef VVIRT
227
228#endif /* CONFIG_X86_64 */
229
230	/* init_task */
231	. = ALIGN(THREAD_SIZE);
232	.data.init_task : AT(ADDR(.data.init_task) - LOAD_OFFSET) {
233		*(.data.init_task)
234	}
235#ifdef CONFIG_X86_64
236	 :data.init
237#endif
238
239	/*
240	 * smp_locks might be freed after init
241	 * start/end must be page aligned
242	 */
243	. = ALIGN(PAGE_SIZE);
244	.smp_locks : AT(ADDR(.smp_locks) - LOAD_OFFSET) {
245		__smp_locks = .;
246		*(.smp_locks)
247		__smp_locks_end = .;
248		. = ALIGN(PAGE_SIZE);
249	}
250
251	/* Init code and data - will be freed after init */
252	. = ALIGN(PAGE_SIZE);
253	.init.text : AT(ADDR(.init.text) - LOAD_OFFSET) {
254		__init_begin = .; /* paired with __init_end */
255		_sinittext = .;
256		INIT_TEXT
257		_einittext = .;
258	}
259
260	.init.data : AT(ADDR(.init.data) - LOAD_OFFSET) {
261		INIT_DATA
262	}
263
264	. = ALIGN(16);
265	.init.setup : AT(ADDR(.init.setup) - LOAD_OFFSET) {
266		__setup_start = .;
267		*(.init.setup)
268		__setup_end = .;
269	}
270	.initcall.init : AT(ADDR(.initcall.init) - LOAD_OFFSET) {
271		__initcall_start = .;
272		INITCALLS
273		__initcall_end = .;
274	}
275
276	.con_initcall.init : AT(ADDR(.con_initcall.init) - LOAD_OFFSET) {
277		__con_initcall_start = .;
278		*(.con_initcall.init)
279		__con_initcall_end = .;
280	}
281
282	.x86_cpu_dev.init : AT(ADDR(.x86_cpu_dev.init) - LOAD_OFFSET) {
283		__x86_cpu_dev_start = .;
284		*(.x86_cpu_dev.init)
285		__x86_cpu_dev_end = .;
286	}
287
288	SECURITY_INIT
289
290	. = ALIGN(8);
291	.parainstructions : AT(ADDR(.parainstructions) - LOAD_OFFSET) {
292		__parainstructions = .;
293		*(.parainstructions)
294		__parainstructions_end = .;
295	}
296
297	. = ALIGN(8);
298	.altinstructions : AT(ADDR(.altinstructions) - LOAD_OFFSET) {
299		__alt_instructions = .;
300		*(.altinstructions)
301		__alt_instructions_end = .;
302	}
303
304	.altinstr_replacement : AT(ADDR(.altinstr_replacement) - LOAD_OFFSET) {
305		*(.altinstr_replacement)
306	}
307
308	/*
309	 * .exit.text is discard at runtime, not link time, to deal with
310	 *  references from .altinstructions and .eh_frame
311	 */
312	.exit.text : AT(ADDR(.exit.text) - LOAD_OFFSET) {
313		EXIT_TEXT
314	}
315
316	.exit.data : AT(ADDR(.exit.data) - LOAD_OFFSET) {
317		EXIT_DATA
318	}
319
320#ifdef CONFIG_BLK_DEV_INITRD
321	. = ALIGN(PAGE_SIZE);
322	.init.ramfs : AT(ADDR(.init.ramfs) - LOAD_OFFSET) {
323		__initramfs_start = .;
324		*(.init.ramfs)
325		__initramfs_end = .;
326	}
327#endif
328
329#if defined(CONFIG_X86_64) && defined(CONFIG_SMP)
330	/*
331	 * percpu offsets are zero-based on SMP.  PERCPU_VADDR() changes the
332	 * output PHDR, so the next output section - __data_nosave - should
333	 * start another section data.init2.  Also, pda should be at the head of
334	 * percpu area.  Preallocate it and define the percpu offset symbol
335	 * so that it can be accessed as a percpu variable.
336	 */
337	. = ALIGN(PAGE_SIZE);
338	PERCPU_VADDR(0, :percpu)
339#else
340	PERCPU(PAGE_SIZE)
341#endif
342
343	. = ALIGN(PAGE_SIZE);
344
345	/* freed after init ends here */
346	.init.end : AT(ADDR(.init.end) - LOAD_OFFSET) {
347		__init_end = .;
348	}
349
350#ifdef CONFIG_X86_64
351	.data_nosave : AT(ADDR(.data_nosave) - LOAD_OFFSET) {
352		. = ALIGN(PAGE_SIZE);
353		__nosave_begin = .;
354		*(.data.nosave)
355		. = ALIGN(PAGE_SIZE);
356		__nosave_end = .;
357	} :data.init2
358	/* use another section data.init2, see PERCPU_VADDR() above */
359#endif
360
361	/* BSS */
362	. = ALIGN(PAGE_SIZE);
363	.bss : AT(ADDR(.bss) - LOAD_OFFSET) {
364		__bss_start = .;
365		*(.bss.page_aligned)
366		*(.bss)
367		. = ALIGN(4);
368		__bss_stop = .;
369	}
370
371	. = ALIGN(PAGE_SIZE);
372	.brk : AT(ADDR(.brk) - LOAD_OFFSET) {
373		__brk_base = .;
374		. += 64 * 1024;		/* 64k alignment slop space */
375		*(.brk_reservation)	/* areas brk users have reserved */
376		__brk_limit = .;
377	}
378
379	.end : AT(ADDR(.end) - LOAD_OFFSET) {
380		_end = .;
381	}
382
383	/* Sections to be discarded */
384	/DISCARD/ : {
385		*(.exitcall.exit)
386		*(.eh_frame)
387		*(.discard)
388	}
389
390        STABS_DEBUG
391        DWARF_DEBUG
392}
393
394
395#ifdef CONFIG_X86_32
396. = ASSERT((_end - LOAD_OFFSET <= KERNEL_IMAGE_SIZE),
397	   "kernel image bigger than KERNEL_IMAGE_SIZE");
398#else
399/*
400 * Per-cpu symbols which need to be offset from __per_cpu_load
401 * for the boot processor.
402 */
403#define INIT_PER_CPU(x) init_per_cpu__##x = per_cpu__##x + __per_cpu_load
404INIT_PER_CPU(gdt_page);
405INIT_PER_CPU(irq_stack_union);
406
407/*
408 * Build-time check on the image size:
409 */
410. = ASSERT((_end - _text <= KERNEL_IMAGE_SIZE),
411	   "kernel image bigger than KERNEL_IMAGE_SIZE");
412
413#ifdef CONFIG_SMP
414. = ASSERT((per_cpu__irq_stack_union == 0),
415           "irq_stack_union is not at start of per-cpu area");
416#endif
417
418#endif /* CONFIG_X86_32 */
419
420#ifdef CONFIG_KEXEC
421#include <asm/kexec.h>
422
423. = ASSERT(kexec_control_code_size <= KEXEC_CONTROL_CODE_MAX_SIZE,
424           "kexec control code size is too big");
425#endif
426
427