1#include <asm/vdso.h> 2 3/* 4 * Linker script for vDSO. This is an ELF shared object prelinked to 5 * its virtual address, and with only one read-only segment. 6 * This script controls its layout. 7 */ 8 9#if defined(BUILD_VDSO64) 10# define SHDR_SIZE 64 11#elif defined(BUILD_VDSO32) || defined(BUILD_VDSOX32) 12# define SHDR_SIZE 40 13#else 14# error unknown VDSO target 15#endif 16 17#define NUM_FAKE_SHDRS 13 18 19SECTIONS 20{ 21 /* 22 * User/kernel shared data is before the vDSO. This may be a little 23 * uglier than putting it after the vDSO, but it avoids issues with 24 * non-allocatable things that dangle past the end of the PT_LOAD 25 * segment. 26 */ 27 28 vvar_start = . - 2 * PAGE_SIZE; 29 vvar_page = vvar_start; 30 31 /* Place all vvars at the offsets in asm/vvar.h. */ 32#define EMIT_VVAR(name, offset) vvar_ ## name = vvar_page + offset; 33#define __VVAR_KERNEL_LDS 34#include <asm/vvar.h> 35#undef __VVAR_KERNEL_LDS 36#undef EMIT_VVAR 37 38 pvclock_page = vvar_start + PAGE_SIZE; 39 40 . = SIZEOF_HEADERS; 41 42 .hash : { *(.hash) } :text 43 .gnu.hash : { *(.gnu.hash) } 44 .dynsym : { *(.dynsym) } 45 .dynstr : { *(.dynstr) } 46 .gnu.version : { *(.gnu.version) } 47 .gnu.version_d : { *(.gnu.version_d) } 48 .gnu.version_r : { *(.gnu.version_r) } 49 50 .dynamic : { *(.dynamic) } :text :dynamic 51 52 .rodata : { 53 *(.rodata*) 54 *(.data*) 55 *(.sdata*) 56 *(.got.plt) *(.got) 57 *(.gnu.linkonce.d.*) 58 *(.bss*) 59 *(.dynbss*) 60 *(.gnu.linkonce.b.*) 61 62 /* 63 * Ideally this would live in a C file, but that won't 64 * work cleanly for x32 until we start building the x32 65 * C code using an x32 toolchain. 66 */ 67 VDSO_FAKE_SECTION_TABLE_START = .; 68 . = . + NUM_FAKE_SHDRS * SHDR_SIZE; 69 VDSO_FAKE_SECTION_TABLE_END = .; 70 } :text 71 72 .fake_shstrtab : { *(.fake_shstrtab) } :text 73 74 75 .note : { *(.note.*) } :text :note 76 77 .eh_frame_hdr : { *(.eh_frame_hdr) } :text :eh_frame_hdr 78 .eh_frame : { KEEP (*(.eh_frame)) } :text 79 80 81 /* 82 * Text is well-separated from actual data: there's plenty of 83 * stuff that isn't used at runtime in between. 84 */ 85 86 .text : { *(.text*) } :text =0x90909090, 87 88 /* 89 * At the end so that eu-elflint stays happy when vdso2c strips 90 * these. A better implementation would avoid allocating space 91 * for these. 92 */ 93 .altinstructions : { *(.altinstructions) } :text 94 .altinstr_replacement : { *(.altinstr_replacement) } :text 95 96 /DISCARD/ : { 97 *(.discard) 98 *(.discard.*) 99 *(__bug_table) 100 } 101} 102 103/* 104 * Very old versions of ld do not recognize this name token; use the constant. 105 */ 106#define PT_GNU_EH_FRAME 0x6474e550 107 108/* 109 * We must supply the ELF program headers explicitly to get just one 110 * PT_LOAD segment, and set the flags explicitly to make segments read-only. 111 */ 112PHDRS 113{ 114 text PT_LOAD FLAGS(5) FILEHDR PHDRS; /* PF_R|PF_X */ 115 dynamic PT_DYNAMIC FLAGS(4); /* PF_R */ 116 note PT_NOTE FLAGS(4); /* PF_R */ 117 eh_frame_hdr PT_GNU_EH_FRAME; 118} 119