Commit dfc20895 authored by Sam Ravnborg's avatar Sam Ravnborg Committed by Ingo Molnar
Browse files

x86, vmlinux.lds: unify .text output sections 



32 bit x86 had a dedicated .text.head output section,
whereas 64 bit had it all in a single output section.

In the unified version the dedicated .text.head output section
was kept to have full control over the head code.

32 bit:

- Moved definition of _stext to the linker script.
  The definition is located _after_ .text.page_aligned as this
  is what 32 bit did before.

The ALIGN(8) was introduced so we hit the exact same address
(on the tested config) before and after the move.

I assume that it is a bug that _stext did not cover the
.text.page_aligned section - if this is true it can be fixed
in a follow-up patch (and the ugly ALIGN() can be dropped).

[ Impact: 64-bit: cleanup, 32-bit: use the 64-bit linker script ]

Signed-off-by: default avatarSam Ravnborg <sam@ravnborg.org>
Cc: Tim Abbott <tabbott@MIT.EDU>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
LKML-Reference: <1240991249-27117-5-git-send-email-sam@ravnborg.org>
Signed-off-by: default avatarIngo Molnar <mingo@elte.hu>
parent 444e0ae4

arch/x86/kernel/head_32.S

+0 −7
Original line number Diff line number Diff line
@@ -608,13 +608,6 @@ ignore_int: 
ENTRY(initial_code)

	.long i386_start_kernel



.section .text

/*

 * Real beginning of normal "text" segment

 */

ENTRY(stext)

ENTRY(_stext)



/*

 * BSS section

 */

arch/x86/kernel/vmlinux.lds.S

+31 −0
Original line number Diff line number Diff line
@@ -64,6 +64,37 @@ SECTIONS 
        phys_startup_64 = startup_64 - LOAD_OFFSET;

#endif



	/* Text and read-only data */



	/* bootstrapping code */

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

		_text = .;

		*(.text.head)

	} :text = 0x9090



	/* The rest of the text */

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

#ifdef CONFIG_X86_32

		/* not really needed, already page aligned */

		. = ALIGN(PAGE_SIZE);

		*(.text.page_aligned)

#endif

		. = ALIGN(8);

		_stext = .;

		TEXT_TEXT

		SCHED_TEXT

		LOCK_TEXT

		KPROBES_TEXT

		IRQENTRY_TEXT

		*(.fixup)

		*(.gnu.warning)

		/* End of text section */

		_etext = .;

	} :text = 0x9090



	NOTES :text :note





#ifdef CONFIG_X86_32

# include "vmlinux_32.lds.S"

#else

arch/x86/kernel/vmlinux_32.lds.S

+0 −24
Original line number Diff line number Diff line 
	/* Text and read-only data */

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

		_text = .;

		*(.text.head)

	} :text = 0x9090



	/* read-only */

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

		/* not really needed, already page aligned */

		. = ALIGN(PAGE_SIZE);

		*(.text.page_aligned)

		TEXT_TEXT

		SCHED_TEXT

		LOCK_TEXT

		KPROBES_TEXT

		IRQENTRY_TEXT

		*(.fixup)

		*(.gnu.warning)

		/* End of text section */

		_etext = .;

	} :text = 0x9090



	NOTES :text :note



	/* Exception table */

	. = ALIGN(16);

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

arch/x86/kernel/vmlinux_64.lds.S

+0 −20
Original line number Diff line number Diff line 
	/* Text and read-only data */

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

		_text = .;

		/* First the code that has to be first for bootstrapping */

		*(.text.head)

		_stext = .;

		/* Then the rest */

		TEXT_TEXT

		SCHED_TEXT

		LOCK_TEXT

		KPROBES_TEXT

		IRQENTRY_TEXT

		*(.fixup)

		*(.gnu.warning)

		/* End of text section */

		_etext = .;

	} :text = 0x9090



	NOTES :text :note



	/* Exception table */

	. = ALIGN(16);

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

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