2 * ld script to make ARM Linux kernel
3 * taken from the i386 version by Russell King
4 * Written by Martin Mares <mj@atrey.karlin.mff.cuni.cz>
7 #include <asm-generic/vmlinux.lds.h>
9 #include <asm/kernel-pgtable.h>
10 #include <asm/thread_info.h>
11 #include <asm/memory.h>
13 #include <asm/pgtable.h>
14 #include <asm/cache.h>
18 /* .exit.text needed in case of alternative patching */
19 #define ARM_EXIT_KEEP(x) x
20 #define ARM_EXIT_DISCARD(x)
27 #define HYPERVISOR_TEXT \
29 * Align to 4 KB so that \
30 * a) the HYP vector table is at its minimum \
31 * alignment of 2048 bytes \
32 * b) the HYP init code will not cross a page \
33 * boundary if its size does not exceed \
34 * 4 KB (see related ASSERT() below) \
37 VMLINUX_SYMBOL(__hyp_idmap_text_start) = .; \
39 VMLINUX_SYMBOL(__hyp_idmap_text_end) = .; \
40 VMLINUX_SYMBOL(__hyp_text_start) = .; \
42 VMLINUX_SYMBOL(__hyp_text_end) = .;
46 VMLINUX_SYMBOL(__idmap_text_start) = .; \
48 VMLINUX_SYMBOL(__idmap_text_end) = .;
50 #ifdef CONFIG_HIBERNATION
51 #define HIBERNATE_TEXT \
53 VMLINUX_SYMBOL(__hibernate_exit_text_start) = .;\
54 *(.hibernate_exit.text) \
55 VMLINUX_SYMBOL(__hibernate_exit_text_end) = .;
57 #define HIBERNATE_TEXT
60 #ifdef CONFIG_UNMAP_KERNEL_AT_EL0
62 . = ALIGN(PAGE_SIZE); \
63 VMLINUX_SYMBOL(__entry_tramp_text_start) = .; \
64 KEEP(*(.entry.tramp.text)) \
65 . = ALIGN(PAGE_SIZE); \
66 VMLINUX_SYMBOL(__entry_tramp_text_end) = .;
72 * The size of the PE/COFF section that covers the kernel image, which
73 * runs from stext to _edata, must be a round multiple of the PE/COFF
74 * FileAlignment, which we set to its minimum value of 0x200. 'stext'
75 * itself is 4 KB aligned, so padding out _edata to a 0x200 aligned
76 * boundary should be sufficient.
78 PECOFF_FILE_ALIGNMENT = 0x200;
81 #define PECOFF_EDATA_PADDING \
82 .pecoff_edata_padding : { BYTE(0); . = ALIGN(PECOFF_FILE_ALIGNMENT); }
84 #define PECOFF_EDATA_PADDING
87 #if defined(CONFIG_DEBUG_ALIGN_RODATA)
89 * 4 KB granule: 1 level 2 entry
90 * 16 KB granule: 128 level 3 entries, with contiguous bit
91 * 64 KB granule: 32 level 3 entries, with contiguous bit
93 #define SEGMENT_ALIGN SZ_2M
96 * 4 KB granule: 16 level 3 entries, with contiguous bit
97 * 16 KB granule: 4 level 3 entries, without contiguous bit
98 * 64 KB granule: 1 level 3 entry
100 #define SEGMENT_ALIGN SZ_64K
106 * XXX: The linker does not define how output sections are
107 * assigned to input sections when there are multiple statements
108 * matching the same input section name. There is no documented
112 ARM_EXIT_DISCARD(EXIT_TEXT)
113 ARM_EXIT_DISCARD(EXIT_DATA)
118 *(.dynsym .dynstr .hash .gnu.hash)
122 . = KIMAGE_VADDR + TEXT_OFFSET;
128 .text : { /* Real text segment */
129 _stext = .; /* Text and read-only data */
130 __exception_text_start = .;
132 __exception_text_end = .;
147 *(.got) /* Global offset table */
150 . = ALIGN(SEGMENT_ALIGN);
151 _etext = .; /* End of text section */
153 RO_DATA(PAGE_SIZE) /* everything from this point to */
154 EXCEPTION_TABLE(8) /* __init_begin will be marked RO NX */
157 . = ALIGN(SEGMENT_ALIGN);
162 ARM_EXIT_KEEP(EXIT_TEXT)
174 ARM_EXIT_KEEP(EXIT_DATA)
177 PERCPU_SECTION(L1_CACHE_BYTES)
181 __alt_instructions = .;
183 __alt_instructions_end = .;
185 .altinstr_replacement : {
186 *(.altinstr_replacement)
188 .rela.dyn : ALIGN(8) {
192 __rela_offset = ABSOLUTE(ADDR(.rela.dyn) - KIMAGE_VADDR);
193 __rela_size = SIZEOF(.rela.dyn);
195 . = ALIGN(SEGMENT_ALIGN);
200 RW_DATA_SECTION(L1_CACHE_BYTES, PAGE_SIZE, THREAD_SIZE)
203 * Data written with the MMU off but read with the MMU on requires
204 * cache lines to be invalidated, discarding up to a Cache Writeback
205 * Granule (CWG) of data from the cache. Keep the section that
206 * requires this type of maintenance to be in its own Cache Writeback
207 * Granule (CWG) area so the cache maintenance operations don't
208 * interfere with adjacent data.
210 .mmuoff.data.write : ALIGN(SZ_2K) {
211 __mmuoff_data_start = .;
212 *(.mmuoff.data.write)
215 .mmuoff.data.read : {
217 __mmuoff_data_end = .;
225 . = ALIGN(PAGE_SIZE);
229 . += SWAPPER_DIR_SIZE;
231 #ifdef CONFIG_ARM64_SW_TTBR0_PAN
233 . += RESERVED_TTBR0_SIZE;
236 #ifdef CONFIG_UNMAP_KERNEL_AT_EL0
249 * The HYP init code and ID map text can't be longer than a page each,
250 * and should not cross a page boundary.
252 ASSERT(__hyp_idmap_text_end - (__hyp_idmap_text_start & ~(SZ_4K - 1)) <= SZ_4K,
253 "HYP init code too big or misaligned")
254 ASSERT(__idmap_text_end - (__idmap_text_start & ~(SZ_4K - 1)) <= SZ_4K,
255 "ID map text too big or misaligned")
256 #ifdef CONFIG_HIBERNATION
257 ASSERT(__hibernate_exit_text_end - (__hibernate_exit_text_start & ~(SZ_4K - 1))
258 <= SZ_4K, "Hibernate exit text too big or misaligned")
261 #ifdef CONFIG_UNMAP_KERNEL_AT_EL0
262 ASSERT((__entry_tramp_text_end - __entry_tramp_text_start) == PAGE_SIZE,
263 "Entry trampoline text too big")
266 * If padding is applied before .head.text, virt<->phys conversions will fail.
268 ASSERT(_text == (KIMAGE_VADDR + TEXT_OFFSET), "HEAD is misaligned")