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root/arch/x86/kernel/vmlinux_32.lds.S

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/* ld script to make i386 Linux kernel
 * Written by Martin Mares <mj@atrey.karlin.mff.cuni.cz>;
 *
 * Don't define absolute symbols until and unless you know that symbol
 * value is should remain constant even if kernel image is relocated
 * at run time. Absolute symbols are not relocated. If symbol value should
 * change if kernel is relocated, make the symbol section relative and
 * put it inside the section definition.
 */

#define LOAD_OFFSET __PAGE_OFFSET

#include <asm-generic/vmlinux.lds.h>
#include <asm/thread_info.h>
#include <asm/page.h>
#include <asm/cache.h>
#include <asm/boot.h>

OUTPUT_FORMAT("elf32-i386", "elf32-i386", "elf32-i386")
OUTPUT_ARCH(i386)
ENTRY(phys_startup_32)
jiffies = jiffies_64;

PHDRS {
        text PT_LOAD FLAGS(5);  /* R_E */
        data PT_LOAD FLAGS(7);  /* RWE */
        note PT_NOTE FLAGS(0);  /* ___ */
}
SECTIONS
{
  . = LOAD_OFFSET + LOAD_PHYSICAL_ADDR;
  phys_startup_32 = startup_32 - LOAD_OFFSET;

  .text.head : AT(ADDR(.text.head) - LOAD_OFFSET) {
        _text = .;                      /* Text and read-only data */
        *(.text.head)
  } :text = 0x9090

  /* read-only */
  .text : AT(ADDR(.text) - LOAD_OFFSET) {
        . = ALIGN(PAGE_SIZE); /* not really needed, already page aligned */
        *(.text.page_aligned)
        TEXT_TEXT
        SCHED_TEXT
        LOCK_TEXT
        KPROBES_TEXT
        *(.fixup)
        *(.gnu.warning)
        _etext = .;                     /* End of text section */
  } :text = 0x9090

  NOTES :text :note

  . = ALIGN(16);                /* Exception table */
  __ex_table : AT(ADDR(__ex_table) - LOAD_OFFSET) {
        __start___ex_table = .;
         *(__ex_table)
        __stop___ex_table = .;
  } :text = 0x9090

  RODATA

  /* writeable */
  . = ALIGN(PAGE_SIZE);
  .data : AT(ADDR(.data) - LOAD_OFFSET) {       /* Data */
        DATA_DATA
        CONSTRUCTORS
        } :data

  . = ALIGN(PAGE_SIZE);
  .data_nosave : AT(ADDR(.data_nosave) - LOAD_OFFSET) {
        __nosave_begin = .;
        *(.data.nosave)
        . = ALIGN(PAGE_SIZE);
        __nosave_end = .;
  }

  . = ALIGN(PAGE_SIZE);
  .data.page_aligned : AT(ADDR(.data.page_aligned) - LOAD_OFFSET) {
        *(.data.page_aligned)
        *(.data.idt)
  }

  . = ALIGN(32);
  .data.cacheline_aligned : AT(ADDR(.data.cacheline_aligned) - LOAD_OFFSET) {
        *(.data.cacheline_aligned)
  }

  /* rarely changed data like cpu maps */
  . = ALIGN(32);
  .data.read_mostly : AT(ADDR(.data.read_mostly) - LOAD_OFFSET) {
        *(.data.read_mostly)
        _edata = .;             /* End of data section */
  }

  . = ALIGN(THREAD_SIZE);       /* init_task */
  .data.init_task : AT(ADDR(.data.init_task) - LOAD_OFFSET) {
        *(.data.init_task)
  }

  /* might get freed after init */
  . = ALIGN(PAGE_SIZE);
  .smp_locks : AT(ADDR(.smp_locks) - LOAD_OFFSET) {
        __smp_locks = .;
        *(.smp_locks)
        __smp_locks_end = .;
  }
  /* will be freed after init
   * Following ALIGN() is required to make sure no other data falls on the
   * same page where __smp_alt_end is pointing as that page might be freed
   * after boot. Always make sure that ALIGN() directive is present after
   * the section which contains __smp_alt_end.
   */
  . = ALIGN(PAGE_SIZE);

  /* will be freed after init */
  . = ALIGN(PAGE_SIZE);         /* Init code and data */
  .init.text : AT(ADDR(.init.text) - LOAD_OFFSET) {
        __init_begin = .;
        _sinittext = .;
        INIT_TEXT
        _einittext = .;
  }
  .init.data : AT(ADDR(.init.data) - LOAD_OFFSET) {
        INIT_DATA
  }
  . = ALIGN(16);
  .init.setup : AT(ADDR(.init.setup) - LOAD_OFFSET) {
        __setup_start = .;
        *(.init.setup)
        __setup_end = .;
   }
  .initcall.init : AT(ADDR(.initcall.init) - LOAD_OFFSET) {
        __initcall_start = .;
        INITCALLS
        __initcall_end = .;
  }
  .con_initcall.init : AT(ADDR(.con_initcall.init) - LOAD_OFFSET) {
        __con_initcall_start = .;
        *(.con_initcall.init)
        __con_initcall_end = .;
  }
  .x86_cpu_dev.init : AT(ADDR(.x86_cpu_dev.init) - LOAD_OFFSET) {
        __x86_cpu_dev_start = .;
        *(.x86_cpu_dev.init)
        __x86_cpu_dev_end = .;
  }
  SECURITY_INIT
  . = ALIGN(4);
  .altinstructions : AT(ADDR(.altinstructions) - LOAD_OFFSET) {
        __alt_instructions = .;
        *(.altinstructions)
        __alt_instructions_end = .;
  }
  .altinstr_replacement : AT(ADDR(.altinstr_replacement) - LOAD_OFFSET) {
        *(.altinstr_replacement)
  }
  . = ALIGN(4);
  .parainstructions : AT(ADDR(.parainstructions) - LOAD_OFFSET) {
        __parainstructions = .;
        *(.parainstructions)
        __parainstructions_end = .;
  }
  /* .exit.text is discard at runtime, not link time, to deal with references
     from .altinstructions and .eh_frame */
  .exit.text : AT(ADDR(.exit.text) - LOAD_OFFSET) {
        EXIT_TEXT
  }
  .exit.data : AT(ADDR(.exit.data) - LOAD_OFFSET) {
        EXIT_DATA
  }
#if defined(CONFIG_BLK_DEV_INITRD)
  . = ALIGN(PAGE_SIZE);
  .init.ramfs : AT(ADDR(.init.ramfs) - LOAD_OFFSET) {
        __initramfs_start = .;
        *(.init.ramfs)
        __initramfs_end = .;
  }
#endif
  . = ALIGN(PAGE_SIZE);
  .data.percpu  : AT(ADDR(.data.percpu) - LOAD_OFFSET) {
        __per_cpu_start = .;
        *(.data.percpu.page_aligned)
        *(.data.percpu)
        *(.data.percpu.shared_aligned)
        __per_cpu_end = .;
  }
  . = ALIGN(PAGE_SIZE);
  /* freed after init ends here */

  .bss : AT(ADDR(.bss) - LOAD_OFFSET) {
        __init_end = .;
        __bss_start = .;                /* BSS */
        *(.bss.page_aligned)
        *(.bss)
        . = ALIGN(4);
        __bss_stop = .;
        _end = . ;
        /* This is where the kernel creates the early boot page tables */
        . = ALIGN(PAGE_SIZE);
        pg0 = . ;
  }

  /* Sections to be discarded */
  /DISCARD/ : {
        *(.exitcall.exit)
        }

  STABS_DEBUG

  DWARF_DEBUG
}

#ifdef CONFIG_KEXEC
/* Link time checks */
#include <asm/kexec.h>

ASSERT(kexec_control_code_size <= KEXEC_CONTROL_CODE_MAX_SIZE,
       "kexec control code size is too big")
#endif

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