1 /*
2 * Linker script for vDSO. This is an ELF shared object prelinked to
3 * its virtual address, and with only one read-only segment.
4 * This script controls its layout.
5 */
6
7 #if defined(BUILD_VDSO64)
8 # define SHDR_SIZE 64
9 #elif defined(BUILD_VDSO32)
10 # define SHDR_SIZE 40
11 #else
12 # error unknown VDSO target
13 #endif
14
15 #define NUM_FAKE_SHDRS 7
16
17 SECTIONS
18 {
19 /*
20 * User/kernel shared data is before the vDSO. This may be a little
21 * uglier than putting it after the vDSO, but it avoids issues with
22 * non-allocatable things that dangle past the end of the PT_LOAD
23 * segment. Page size is 8192 for both 64-bit and 32-bit vdso binaries
24 */
25
26 vvar_start = . -8192;
27 vvar_data = vvar_start;
28
29 . = SIZEOF_HEADERS;
30
31 .hash : { *(.hash) } :text
32 .gnu.hash : { *(.gnu.hash) }
33 .dynsym : { *(.dynsym) }
34 .dynstr : { *(.dynstr) }
35 .gnu.version : { *(.gnu.version) }
36 .gnu.version_d : { *(.gnu.version_d) }
37 .gnu.version_r : { *(.gnu.version_r) }
38
39 .dynamic : { *(.dynamic) } :text :dynamic
40
41 .rodata : {
42 *(.rodata*)
43 *(.data*)
44 *(.sdata*)
45 *(.got.plt) *(.got)
46 *(.gnu.linkonce.d.*)
47 *(.bss*)
48 *(.dynbss*)
49 *(.gnu.linkonce.b.*)
50
51 /*
52 * Ideally this would live in a C file: kept in here for
53 * compatibility with x86-64.
54 */
55 VDSO_FAKE_SECTION_TABLE_START = .;
56 . = . + NUM_FAKE_SHDRS * SHDR_SIZE;
57 VDSO_FAKE_SECTION_TABLE_END = .;
58 } :text
59
60 .fake_shstrtab : { *(.fake_shstrtab) } :text
61
62
63 .note : { *(.note.*) } :text :note
64
65 .eh_frame_hdr : { *(.eh_frame_hdr) } :text :eh_frame_hdr
66 .eh_frame : { KEEP (*(.eh_frame)) } :text
67
68
69 /*
70 * Text is well-separated from actual data: there's plenty of
71 * stuff that isn't used at runtime in between.
72 */
73
74 .text : { *(.text*) } :text =0x90909090,
75
76 /DISCARD/ : {
77 *(.discard)
78 *(.discard.*)
79 *(__bug_table)
80 }
81 }
82
83 /*
84 * Very old versions of ld do not recognize this name token; use the constant.
85 */
86 #define PT_GNU_EH_FRAME 0x6474e550
87
88 /*
89 * We must supply the ELF program headers explicitly to get just one
90 * PT_LOAD segment, and set the flags explicitly to make segments read-only.
91 */
92 PHDRS
93 {
94 text PT_LOAD FLAGS(5) FILEHDR PHDRS; /* PF_R|PF_X */
95 dynamic PT_DYNAMIC FLAGS(4); /* PF_R */
96 note PT_NOTE FLAGS(4); /* PF_R */
97 eh_frame_hdr PT_GNU_EH_FRAME;
98 }