arch/x86/kernel/vmlinux_32.lds.S

   1 /* ld script to make i386 Linux kernel
   2  * Written by Martin Mares <mj@atrey.karlin.mff.cuni.cz>;
   3  *
   4  * Don't define absolute symbols until and unless you know that symbol
   5  * value is should remain constant even if kernel image is relocated
   6  * at run time. Absolute symbols are not relocated. If symbol value should
   7  * change if kernel is relocated, make the symbol section relative and
   8  * put it inside the section definition.
   9  */
  10
  11 #define LOAD_OFFSET __PAGE_OFFSET
  12
  13 #include <asm-generic/vmlinux.lds.h>
  14 #include <asm/thread_info.h>
  15 #include <asm/page.h>
  16 #include <asm/cache.h>
  17 #include <asm/boot.h>
  18
  19 OUTPUT_FORMAT("elf32-i386", "elf32-i386", "elf32-i386")
  20 OUTPUT_ARCH(i386)
  21 ENTRY(phys_startup_32)
  22 jiffies = jiffies_64;
  23
  24 PHDRS {
  25         text PT_LOAD FLAGS(5);  /* R_E */
  26         data PT_LOAD FLAGS(7);  /* RWE */
  27         note PT_NOTE FLAGS(0);  /* ___ */
  28 }
  29 SECTIONS
  30 {
  31   . = LOAD_OFFSET + LOAD_PHYSICAL_ADDR;
  32   phys_startup_32 = startup_32 - LOAD_OFFSET;
  33
  34   .text.head : AT(ADDR(.text.head) - LOAD_OFFSET) {
  35         _text = .;                      /* Text and read-only data */
  36         *(.text.head)
  37   } :text = 0x9090
  38
  39   /* read-only */
  40   .text : AT(ADDR(.text) - LOAD_OFFSET) {
  41         . = ALIGN(PAGE_SIZE); /* not really needed, already page aligned */
  42         *(.text.page_aligned)
  43         TEXT_TEXT
  44         SCHED_TEXT
  45         LOCK_TEXT
  46         KPROBES_TEXT
  47         *(.fixup)
  48         *(.gnu.warning)
  49         _etext = .;                     /* End of text section */
  50   } :text = 0x9090
  51
  52   NOTES :text :note
  53
  54   . = ALIGN(16);                /* Exception table */
  55   __ex_table : AT(ADDR(__ex_table) - LOAD_OFFSET) {
  56         __start___ex_table = .;
  57          *(__ex_table)
  58         __stop___ex_table = .;
  59   } :text = 0x9090
  60
  61   RODATA
  62
  63   /* writeable */
  64   . = ALIGN(PAGE_SIZE);
  65   .data : AT(ADDR(.data) - LOAD_OFFSET) {       /* Data */
  66         DATA_DATA
  67         CONSTRUCTORS
  68         } :data
  69
  70   . = ALIGN(PAGE_SIZE);
  71   .data_nosave : AT(ADDR(.data_nosave) - LOAD_OFFSET) {
  72         __nosave_begin = .;
  73         *(.data.nosave)
  74         . = ALIGN(PAGE_SIZE);
  75         __nosave_end = .;
  76   }
  77
  78   . = ALIGN(PAGE_SIZE);
  79   .data.page_aligned : AT(ADDR(.data.page_aligned) - LOAD_OFFSET) {
  80         *(.data.page_aligned)
  81         *(.data.idt)
  82   }
  83
  84   . = ALIGN(32);
  85   .data.cacheline_aligned : AT(ADDR(.data.cacheline_aligned) - LOAD_OFFSET) {
  86         *(.data.cacheline_aligned)
  87   }
  88
  89   /* rarely changed data like cpu maps */
  90   . = ALIGN(32);
  91   .data.read_mostly : AT(ADDR(.data.read_mostly) - LOAD_OFFSET) {
  92         *(.data.read_mostly)
  93         _edata = .;             /* End of data section */
  94   }
  95
  96   . = ALIGN(THREAD_SIZE);       /* init_task */
  97   .data.init_task : AT(ADDR(.data.init_task) - LOAD_OFFSET) {
  98         *(.data.init_task)
  99   }
 100
 101   /* might get freed after init */
 102   . = ALIGN(PAGE_SIZE);
 103   .smp_locks : AT(ADDR(.smp_locks) - LOAD_OFFSET) {
 104         __smp_locks = .;
 105         *(.smp_locks)
 106         __smp_locks_end = .;
 107   }
 108   /* will be freed after init
 109    * Following ALIGN() is required to make sure no other data falls on the
 110    * same page where __smp_alt_end is pointing as that page might be freed
 111    * after boot. Always make sure that ALIGN() directive is present after
 112    * the section which contains __smp_alt_end.
 113    */
 114   . = ALIGN(PAGE_SIZE);
 115
 116   /* will be freed after init */
 117   . = ALIGN(PAGE_SIZE);         /* Init code and data */
 118   .init.text : AT(ADDR(.init.text) - LOAD_OFFSET) {
 119         __init_begin = .;
 120         _sinittext = .;
 121         INIT_TEXT
 122         _einittext = .;
 123   }
 124   .init.data : AT(ADDR(.init.data) - LOAD_OFFSET) {
 125         INIT_DATA
 126   }
 127   . = ALIGN(16);
 128   .init.setup : AT(ADDR(.init.setup) - LOAD_OFFSET) {
 129         __setup_start = .;
 130         *(.init.setup)
 131         __setup_end = .;
 132    }
 133   .initcall.init : AT(ADDR(.initcall.init) - LOAD_OFFSET) {
 134         __initcall_start = .;
 135         INITCALLS
 136         __initcall_end = .;
 137   }
 138   .con_initcall.init : AT(ADDR(.con_initcall.init) - LOAD_OFFSET) {
 139         __con_initcall_start = .;
 140         *(.con_initcall.init)
 141         __con_initcall_end = .;
 142   }
 143   .x86_cpu_dev.init : AT(ADDR(.x86_cpu_dev.init) - LOAD_OFFSET) {
 144         __x86_cpu_dev_start = .;
 145         *(.x86_cpu_dev.init)
 146         __x86_cpu_dev_end = .;
 147   }
 148   SECURITY_INIT
 149   . = ALIGN(4);
 150   .altinstructions : AT(ADDR(.altinstructions) - LOAD_OFFSET) {
 151         __alt_instructions = .;
 152         *(.altinstructions)
 153         __alt_instructions_end = .;
 154   }
 155   .altinstr_replacement : AT(ADDR(.altinstr_replacement) - LOAD_OFFSET) {
 156         *(.altinstr_replacement)
 157   }
 158   . = ALIGN(4);
 159   .parainstructions : AT(ADDR(.parainstructions) - LOAD_OFFSET) {
 160         __parainstructions = .;
 161         *(.parainstructions)
 162         __parainstructions_end = .;
 163   }
 164   /* .exit.text is discard at runtime, not link time, to deal with references
 165      from .altinstructions and .eh_frame */
 166   .exit.text : AT(ADDR(.exit.text) - LOAD_OFFSET) {
 167         EXIT_TEXT
 168   }
 169   .exit.data : AT(ADDR(.exit.data) - LOAD_OFFSET) {
 170         EXIT_DATA
 171   }
 172 #if defined(CONFIG_BLK_DEV_INITRD)
 173   . = ALIGN(PAGE_SIZE);
 174   .init.ramfs : AT(ADDR(.init.ramfs) - LOAD_OFFSET) {
 175         __initramfs_start = .;
 176         *(.init.ramfs)
 177         __initramfs_end = .;
 178   }
 179 #endif
 180   . = ALIGN(PAGE_SIZE);
 181   .data.percpu  : AT(ADDR(.data.percpu) - LOAD_OFFSET) {
 182         __per_cpu_start = .;
 183         *(.data.percpu.page_aligned)
 184         *(.data.percpu)
 185         *(.data.percpu.shared_aligned)
 186         __per_cpu_end = .;
 187   }
 188   . = ALIGN(PAGE_SIZE);
 189   /* freed after init ends here */
 190
 191   .bss : AT(ADDR(.bss) - LOAD_OFFSET) {
 192         __init_end = .;
 193         __bss_start = .;                /* BSS */
 194         *(.bss.page_aligned)
 195         *(.bss)
 196         . = ALIGN(4);
 197         __bss_stop = .;
 198         _end = . ;
 199         /* This is where the kernel creates the early boot page tables */
 200         . = ALIGN(PAGE_SIZE);
 201         pg0 = . ;
 202   }
 203
 204   /* Sections to be discarded */
 205   /DISCARD/ : {
 206         *(.exitcall.exit)
 207         }
 208
 209   STABS_DEBUG
 210
 211   DWARF_DEBUG
 212 }
 213
 214 #ifdef CONFIG_KEXEC
 215 /* Link time checks */
 216 #include <asm/kexec.h>
 217
 218 ASSERT(kexec_control_code_size <= KEXEC_CONTROL_CODE_MAX_SIZE,
 219        "kexec control code size is too big")
 220 #endif