1/* SPDX-License-Identifier: GPL-2.0 */ 2#include <asm/vdso.h> 3 4/* 5 * Linker script for vDSO. This is an ELF shared object prelinked to 6 * its virtual address, and with only one read-only segment. 7 * This script controls its layout. 8 */ 9 10#if defined(BUILD_VDSO64) 11# define SHDR_SIZE 64 12#elif defined(BUILD_VDSO32) || defined(BUILD_VDSOX32) 13# define SHDR_SIZE 40 14#else 15# error unknown VDSO target 16#endif 17 18#define NUM_FAKE_SHDRS 13 19 20SECTIONS 21{ 22 /* 23 * User/kernel shared data is before the vDSO. This may be a little 24 * uglier than putting it after the vDSO, but it avoids issues with 25 * non-allocatable things that dangle past the end of the PT_LOAD 26 * segment. 27 */ 28 29 vvar_start = . - 3 * PAGE_SIZE; 30 vvar_page = vvar_start; 31 32 /* Place all vvars at the offsets in asm/vvar.h. */ 33#define EMIT_VVAR(name, offset) vvar_ ## name = vvar_page + offset; 34#define __VVAR_KERNEL_LDS 35#include <asm/vvar.h> 36#undef __VVAR_KERNEL_LDS 37#undef EMIT_VVAR 38 39 pvclock_page = vvar_start + PAGE_SIZE; 40 hvclock_page = vvar_start + 2 * PAGE_SIZE; 41 42 . = SIZEOF_HEADERS; 43 44 .hash : { *(.hash) } :text 45 .gnu.hash : { *(.gnu.hash) } 46 .dynsym : { *(.dynsym) } 47 .dynstr : { *(.dynstr) } 48 .gnu.version : { *(.gnu.version) } 49 .gnu.version_d : { *(.gnu.version_d) } 50 .gnu.version_r : { *(.gnu.version_r) } 51 52 .dynamic : { *(.dynamic) } :text :dynamic 53 54 .rodata : { 55 *(.rodata*) 56 *(.data*) 57 *(.sdata*) 58 *(.got.plt) *(.got) 59 *(.gnu.linkonce.d.*) 60 *(.bss*) 61 *(.dynbss*) 62 *(.gnu.linkonce.b.*) 63 64 /* 65 * Ideally this would live in a C file, but that won't 66 * work cleanly for x32 until we start building the x32 67 * C code using an x32 toolchain. 68 */ 69 VDSO_FAKE_SECTION_TABLE_START = .; 70 . = . + NUM_FAKE_SHDRS * SHDR_SIZE; 71 VDSO_FAKE_SECTION_TABLE_END = .; 72 } :text 73 74 .fake_shstrtab : { *(.fake_shstrtab) } :text 75 76 77 .note : { *(.note.*) } :text :note 78 79 .eh_frame_hdr : { *(.eh_frame_hdr) } :text :eh_frame_hdr 80 .eh_frame : { KEEP (*(.eh_frame)) } :text 81 82 83 /* 84 * Text is well-separated from actual data: there's plenty of 85 * stuff that isn't used at runtime in between. 86 */ 87 88 .text : { *(.text*) } :text =0x90909090, 89 90 /* 91 * At the end so that eu-elflint stays happy when vdso2c strips 92 * these. A better implementation would avoid allocating space 93 * for these. 94 */ 95 .altinstructions : { *(.altinstructions) } :text 96 .altinstr_replacement : { *(.altinstr_replacement) } :text 97 98 /DISCARD/ : { 99 *(.discard) 100 *(.discard.*) 101 *(__bug_table) 102 } 103} 104 105/* 106 * Very old versions of ld do not recognize this name token; use the constant. 107 */ 108#define PT_GNU_EH_FRAME 0x6474e550 109 110/* 111 * We must supply the ELF program headers explicitly to get just one 112 * PT_LOAD segment, and set the flags explicitly to make segments read-only. 113 */ 114PHDRS 115{ 116 text PT_LOAD FLAGS(5) FILEHDR PHDRS; /* PF_R|PF_X */ 117 dynamic PT_DYNAMIC FLAGS(4); /* PF_R */ 118 note PT_NOTE FLAGS(4); /* PF_R */ 119 eh_frame_hdr PT_GNU_EH_FRAME; 120} 121