Commit 5ded01e8 authored by Eric W. Biederman's avatar Eric W. Biederman Committed by Linus Torvalds
Browse files

[PATCH] kexec: x86_64: vmlinux: fix physical addresses 



The vmlinux on x86_64 does not report the correct physical address of
the kernel.  Instead in the physical address field it currently
reports the virtual address of the kernel.

This is patch is a bug fix that corrects vmlinux to report the
proper physical addresses.

This is potentially a help for crash dump analysis tools.

This definitiely allows bootloaders that load vmlinux as a standard
ELF executable.  Bootloaders directly loading vmlinux become of
practical importance when we consider the kexec on panic case.

Signed-off-by: default avatarEric Biederman <ebiederm@xmission.com>
Signed-off-by: default avatarAndrew Morton <akpm@osdl.org>
Signed-off-by: default avatarLinus Torvalds <torvalds@osdl.org>
parent ad0d75eb

arch/x86_64/Makefile

+1 −1
Original line number Diff line number Diff line
@@ -35,7 +35,7 @@ export IA32_CC IA32_LD IA32_AS IA32_OBJCOPY IA32_CPP 


LDFLAGS		:= -m elf_x86_64

OBJCOPYFLAGS	:= -O binary -R .note -R .comment -S

LDFLAGS_vmlinux := -e stext

LDFLAGS_vmlinux :=



CHECKFLAGS      += -D__x86_64__ -m64

arch/x86_64/kernel/vmlinux.lds.S

+86 −42
Original line number Diff line number Diff line
@@ -2,7 +2,10 @@ 
 * Written by Martin Mares <mj@atrey.karlin.mff.cuni.cz>;

 */



#define LOAD_OFFSET __START_KERNEL_map



#include <asm-generic/vmlinux.lds.h>

#include <asm/page.h>

#include <linux/config.h>



OUTPUT_FORMAT("elf64-x86-64", "elf64-x86-64", "elf64-x86-64")
@@ -11,28 +14,30 @@ ENTRY(phys_startup_64) 
jiffies_64 = jiffies;

SECTIONS

{

  . = 0xffffffff80100000;

  . = __START_KERNEL;

  phys_startup_64 = startup_64 - LOAD_OFFSET;

  _text = .;			/* Text and read-only data */

  .text : {

  .text :  AT(ADDR(.text) - LOAD_OFFSET) {

	*(.text)

	SCHED_TEXT

	LOCK_TEXT

	*(.fixup)

	*(.gnu.warning)

	} = 0x9090

  .text.lock : { *(.text.lock) }	/* out-of-line lock text */

  				/* out-of-line lock text */

  .text.lock : AT(ADDR(.text.lock) - LOAD_OFFSET) { *(.text.lock) }



  _etext = .;			/* End of text section */



  . = ALIGN(16);		/* Exception table */

  __start___ex_table = .;

  __ex_table : { *(__ex_table) }

  __ex_table : AT(ADDR(__ex_table) - LOAD_OFFSET) { *(__ex_table) }

  __stop___ex_table = .;



  RODATA



  .data : {			/* Data */

				/* Data */

  .data : AT(ADDR(.data) - LOAD_OFFSET) {

	*(.data)

	CONSTRUCTORS

	}
@@ -40,62 +45,95 @@ SECTIONS 
  _edata = .;			/* End of data section */



  __bss_start = .;		/* BSS */

  .bss : {

  .bss : AT(ADDR(.bss) - LOAD_OFFSET) {

	*(.bss.page_aligned)	

	*(.bss)

	}

  __bss_end = .;



  . = ALIGN(PAGE_SIZE);

  . = ALIGN(CONFIG_X86_L1_CACHE_BYTES);

  .data.cacheline_aligned : { *(.data.cacheline_aligned) }

  .data.cacheline_aligned : AT(ADDR(.data.cacheline_aligned) - LOAD_OFFSET) {

	*(.data.cacheline_aligned)

  }



#define VSYSCALL_ADDR (-10*1024*1024)

#define VSYSCALL_PHYS_ADDR ((LOADADDR(.data.cacheline_aligned) + SIZEOF(.data.cacheline_aligned) + 4095) & ~(4095))

#define VSYSCALL_VIRT_ADDR ((ADDR(.data.cacheline_aligned) + SIZEOF(.data.cacheline_aligned) + 4095) & ~(4095))



#define VLOAD_OFFSET (VSYSCALL_ADDR - VSYSCALL_PHYS_ADDR)

#define VLOAD(x) (ADDR(x) - VLOAD_OFFSET)



#define VVIRT_OFFSET (VSYSCALL_ADDR - VSYSCALL_VIRT_ADDR)

#define VVIRT(x) (ADDR(x) - VVIRT_OFFSET)



#define AFTER(x)      BINALIGN(LOADADDR(x) + SIZEOF(x), 16)

#define BINALIGN(x,y) (((x) + (y) - 1)  & ~((y) - 1))

#define CACHE_ALIGN(x) BINALIGN(x, CONFIG_X86_L1_CACHE_BYTES)

  . = VSYSCALL_ADDR;

  .vsyscall_0 :	 AT(VSYSCALL_PHYS_ADDR) { *(.vsyscall_0) }

  __vsyscall_0 = VSYSCALL_VIRT_ADDR;



  .vsyscall_0 -10*1024*1024: AT ((LOADADDR(.data.cacheline_aligned) + SIZEOF(.data.cacheline_aligned) + 4095) & ~(4095)) { *(.vsyscall_0) }

  __vsyscall_0 = LOADADDR(.vsyscall_0);

  . = ALIGN(CONFIG_X86_L1_CACHE_BYTES);

  .xtime_lock : AT CACHE_ALIGN(AFTER(.vsyscall_0)) { *(.xtime_lock) }

  xtime_lock = LOADADDR(.xtime_lock);

  .vxtime : AT AFTER(.xtime_lock) { *(.vxtime) }

  vxtime = LOADADDR(.vxtime);

  .wall_jiffies : AT AFTER(.vxtime) { *(.wall_jiffies) }

  wall_jiffies = LOADADDR(.wall_jiffies);

  .sys_tz : AT AFTER(.wall_jiffies) { *(.sys_tz) }

  sys_tz = LOADADDR(.sys_tz);

  .sysctl_vsyscall : AT AFTER(.sys_tz) { *(.sysctl_vsyscall) }

  sysctl_vsyscall = LOADADDR(.sysctl_vsyscall); 

  .xtime : AT AFTER(.sysctl_vsyscall) { *(.xtime) }

  xtime = LOADADDR(.xtime);

  .xtime_lock : AT(VLOAD(.xtime_lock)) { *(.xtime_lock) }

  xtime_lock = VVIRT(.xtime_lock);



  .vxtime : AT(VLOAD(.vxtime)) { *(.vxtime) }

  vxtime = VVIRT(.vxtime);



  .wall_jiffies : AT(VLOAD(.wall_jiffies)) { *(.wall_jiffies) }

  wall_jiffies = VVIRT(.wall_jiffies);



  .sys_tz : AT(VLOAD(.sys_tz)) { *(.sys_tz) }

  sys_tz = VVIRT(.sys_tz);



  .sysctl_vsyscall : AT(VLOAD(.sysctl_vsyscall)) { *(.sysctl_vsyscall) }

  sysctl_vsyscall = VVIRT(.sysctl_vsyscall);



  .xtime : AT(VLOAD(.xtime)) { *(.xtime) }

  xtime = VVIRT(.xtime);



  . = ALIGN(CONFIG_X86_L1_CACHE_BYTES);

  .jiffies : AT CACHE_ALIGN(AFTER(.xtime)) { *(.jiffies) }

  jiffies = LOADADDR(.jiffies);

  .vsyscall_1 ADDR(.vsyscall_0) + 1024: AT (LOADADDR(.vsyscall_0) + 1024) { *(.vsyscall_1) }

  . = LOADADDR(.vsyscall_0) + 4096;

  .jiffies : AT(VLOAD(.jiffies)) { *(.jiffies) }

  jiffies = VVIRT(.jiffies);



  .vsyscall_1 ADDR(.vsyscall_0) + 1024: AT(VLOAD(.vsyscall_1)) { *(.vsyscall_1) }

  .vsyscall_2 ADDR(.vsyscall_0) + 2048: AT(VLOAD(.vsyscall_2)) { *(.vsyscall_2) }

  .vsyscall_3 ADDR(.vsyscall_0) + 3072: AT(VLOAD(.vsyscall_3)) { *(.vsyscall_3) }



  . = VSYSCALL_VIRT_ADDR + 4096;



#undef VSYSCALL_ADDR

#undef VSYSCALL_PHYS_ADDR

#undef VSYSCALL_VIRT_ADDR

#undef VLOAD_OFFSET

#undef VLOAD

#undef VVIRT_OFFSET

#undef VVIRT



  . = ALIGN(8192);		/* init_task */

  .data.init_task : { *(.data.init_task) }

  .data.init_task : AT(ADDR(.data.init_task) - LOAD_OFFSET) {

	*(.data.init_task)

  }



  . = ALIGN(4096);

  .data.page_aligned : { *(.data.page_aligned) }

  .data.page_aligned : AT(ADDR(.data.page_aligned) - LOAD_OFFSET) {

	*(.data.page_aligned)

  }



  . = ALIGN(4096);		/* Init code and data */

  __init_begin = .;

  .init.text : { 

  .init.text : AT(ADDR(.init.text) - LOAD_OFFSET) {

	_sinittext = .;

	*(.init.text)

	_einittext = .;

  }

  __initdata_begin = .;

  .init.data : { *(.init.data) }

  .init.data : AT(ADDR(.init.data) - LOAD_OFFSET) { *(.init.data) }

  __initdata_end = .;

  . = ALIGN(16);

  __setup_start = .;

  .init.setup : { *(.init.setup) }

  .init.setup : AT(ADDR(.init.setup) - LOAD_OFFSET) { *(.init.setup) }

  __setup_end = .;

  __initcall_start = .;

  .initcall.init : {

  .initcall.init : AT(ADDR(.initcall.init) - LOAD_OFFSET) {

	*(.initcall1.init) 

	*(.initcall2.init) 

	*(.initcall3.init)
@@ -106,32 +144,38 @@ SECTIONS 
  }

  __initcall_end = .;

  __con_initcall_start = .;

  .con_initcall.init : { *(.con_initcall.init) }

  .con_initcall.init : AT(ADDR(.con_initcall.init) - LOAD_OFFSET) {

	*(.con_initcall.init)

  }

  __con_initcall_end = .;

  SECURITY_INIT

  . = ALIGN(8);

  __alt_instructions = .;

  .altinstructions : { *(.altinstructions) } 

  .altinstructions : AT(ADDR(.altinstructions) - LOAD_OFFSET) {

	*(.altinstructions)

  }

  __alt_instructions_end = .; 

 .altinstr_replacement : { *(.altinstr_replacement) }

  .altinstr_replacement : AT(ADDR(.altinstr_replacement) - LOAD_OFFSET) {

	*(.altinstr_replacement)

  }

  /* .exit.text is discard at runtime, not link time, to deal with references

     from .altinstructions and .eh_frame */

  .exit.text : { *(.exit.text) }

  .exit.data : { *(.exit.data) }	

  .exit.text : AT(ADDR(.exit.text) - LOAD_OFFSET) { *(.exit.text) }

  .exit.data : AT(ADDR(.exit.data) - LOAD_OFFSET) { *(.exit.data) }

  . = ALIGN(4096);

  __initramfs_start = .;

  .init.ramfs : { *(.init.ramfs) }

  .init.ramfs : AT(ADDR(.init.ramfs) - LOAD_OFFSET) { *(.init.ramfs) }

  __initramfs_end = .;	

  . = ALIGN(32);

  __per_cpu_start = .;

  .data.percpu  : { *(.data.percpu) }

  .data.percpu  : AT(ADDR(.data.percpu) - LOAD_OFFSET) { *(.data.percpu) }

  __per_cpu_end = .;

  . = ALIGN(4096);

  __init_end = .;



  . = ALIGN(4096);

  __nosave_begin = .;

  .data_nosave : { *(.data.nosave) }

  .data_nosave : AT(ADDR(.data_nosave) - LOAD_OFFSET) { *(.data.nosave) }

  . = ALIGN(4096);

  __nosave_end = .;