[PATCH v2 0/2] Linker script cleanup patches for arm

[PATCH v2 0/2] Linker script cleanup patches for arm

[Tim Abbott]

This is an updated version of the patch series I sent in late July
cleaning up the arm architecture's linker scripts.  The only change is
that it is rebased on top of Linus's current master.

This cross-architecture linker script cleanup project is in
preparation for adding support for building the kernel with
-ffunction-sections -fdata-sections, which is a prerequisite for
Ksplice.

	-Tim Abbott

Nelson Elhage (1):
  arm: Clean up linker script using new linker script macros.

Tim Abbott (1):
  arm: convert to use __HEAD and HEAD_TEXT macros.

 arch/arm/kernel/head-nommu.S  |    2 +-
 arch/arm/kernel/head.S        |    2 +-
 arch/arm/kernel/vmlinux.lds.S |   84 ++++++++++++-----------------------------
 3 files changed, 26 insertions(+), 62 deletions(-)

[PATCH v2 1/2] arm: convert to use __HEAD and HEAD_TEXT macros.

[Tim Abbott]

This has the consequence of changing the section name used for head
code from ".text.head" to ".head.text".  Since this commit changes all
users in the architecture, this change should be harmless.

The .text.head output section is eliminated and the head text code is
included at the start of the .init output section.

Signed-off-by: Tim Abbott <tabbott@ksplice.com>
Cc: Russell King <rmk+kernel@arm.linux.org.uk>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
---
 arch/arm/kernel/head-nommu.S  |    2 +-
 arch/arm/kernel/head.S        |    2 +-
 arch/arm/kernel/vmlinux.lds.S |    8 +++-----
 3 files changed, 5 insertions(+), 7 deletions(-)

diff --git a/arch/arm/kernel/head-nommu.S b/arch/arm/kernel/head-nommu.S
index e5dfc28..573b803 100644
--- a/arch/arm/kernel/head-nommu.S
+++ b/arch/arm/kernel/head-nommu.S
@@ -32,7 +32,7 @@
  * numbers for r1.
  *
  */
-	.section ".text.head", "ax"
+	__HEAD
 ENTRY(stext)
 	setmode	PSR_F_BIT | PSR_I_BIT | SVC_MODE, r9 @ ensure svc mode
 						@ and irqs disabled
diff --git a/arch/arm/kernel/head.S b/arch/arm/kernel/head.S
index 38ccbe1..eb62bf9 100644
--- a/arch/arm/kernel/head.S
+++ b/arch/arm/kernel/head.S
@@ -74,7 +74,7 @@
  * crap here - that's what the boot loader (or in extreme, well justified
  * circumstances, zImage) is for.
  */
-	.section ".text.head", "ax"
+	__HEAD
 ENTRY(stext)
 	setmode	PSR_F_BIT | PSR_I_BIT | SVC_MODE, r9 @ ensure svc mode
 						@ and irqs disabled
diff --git a/arch/arm/kernel/vmlinux.lds.S b/arch/arm/kernel/vmlinux.lds.S
index 5cc4812..d3fbd98 100644
--- a/arch/arm/kernel/vmlinux.lds.S
+++ b/arch/arm/kernel/vmlinux.lds.S
@@ -24,13 +24,11 @@ SECTIONS
 #else
 	. = PAGE_OFFSET + TEXT_OFFSET;
 #endif
-	.text.head : {
-		_stext = .;
-		_sinittext = .;
-		*(.text.head)
-	}
 
 	.init : {			/* Init code and data		*/
+		_stext = .;
+		_sinittext = .;
+			HEAD_TEXT
 			INIT_TEXT
 		_einittext = .;
 		__proc_info_begin = .;
-- 
1.6.3.3

[PATCH v2 2/2] arm: Clean up linker script using new linker script macros.

[Tim Abbott]

From: Nelson Elhage <nelhage@ksplice.com>

This patch is mostly a straightforward translation. The primary side
effect to the resulting vmlinux should be to increase the alignment on
the initramfs to the standard PAGE_SIZE from 32 bytes.

Signed-off-by: Nelson Elhage <nelhage@ksplice.com>
Cc: Russell King <rmk+kernel@arm.linux.org.uk>
---
 arch/arm/kernel/vmlinux.lds.S |   76 +++++++++++-----------------------------
 1 files changed, 21 insertions(+), 55 deletions(-)

diff --git a/arch/arm/kernel/vmlinux.lds.S b/arch/arm/kernel/vmlinux.lds.S
index d3fbd98..3cd6ff0 100644
--- a/arch/arm/kernel/vmlinux.lds.S
+++ b/arch/arm/kernel/vmlinux.lds.S
@@ -40,43 +40,29 @@ SECTIONS
 		__tagtable_begin = .;
 			*(.taglist.init)
 		__tagtable_end = .;
-		. = ALIGN(16);
-		__setup_start = .;
-			*(.init.setup)
-		__setup_end = .;
+
+		INIT_SETUP(16)
+
 		__early_begin = .;
 			*(.early_param.init)
 		__early_end = .;
-		__initcall_start = .;
-			INITCALLS
-		__initcall_end = .;
-		__con_initcall_start = .;
-			*(.con_initcall.init)
-		__con_initcall_end = .;
-		__security_initcall_start = .;
-			*(.security_initcall.init)
-		__security_initcall_end = .;
-#ifdef CONFIG_BLK_DEV_INITRD
-		. = ALIGN(32);
-		__initramfs_start = .;
-			usr/built-in.o(.init.ramfs)
-		__initramfs_end = .;
-#endif
-		. = ALIGN(PAGE_SIZE);
-		__per_cpu_load = .;
-		__per_cpu_start = .;
-			*(.data.percpu.page_aligned)
-			*(.data.percpu)
-			*(.data.percpu.shared_aligned)
-		__per_cpu_end = .;
+
+		INIT_CALLS
+		CON_INITCALL
+		SECURITY_INITCALL
+		INIT_RAM_FS
+
 #ifndef CONFIG_XIP_KERNEL
 		__init_begin = _stext;
 		INIT_DATA
-		. = ALIGN(PAGE_SIZE);
-		__init_end = .;
 #endif
 	}
 
+	PERCPU(PAGE_SIZE)
+
+	. = ALIGN(PAGE_SIZE);
+	__init_end = .;
+
 	/DISCARD/ : {			/* Exit code and data		*/
 		EXIT_TEXT
 		EXIT_DATA
@@ -155,7 +141,7 @@ SECTIONS
 		 * first, the init task union, aligned
 		 * to an 8192 byte boundary.
 		 */
-		*(.data.init_task)
+		INIT_TASK_DATA(THREAD_SIZE)
 
 #ifdef CONFIG_XIP_KERNEL
 		. = ALIGN(PAGE_SIZE);
@@ -165,17 +151,8 @@ SECTIONS
 		__init_end = .;
 #endif
 
-		. = ALIGN(PAGE_SIZE);
-		__nosave_begin = .;
-		*(.data.nosave)
-		. = ALIGN(PAGE_SIZE);
-		__nosave_end = .;
-
-		/*
-		 * then the cacheline aligned data
-		 */
-		. = ALIGN(32);
-		*(.data.cacheline_aligned)
+		NOSAVE_DATA
+		CACHELINE_ALIGNED_DATA(32)
 
 		/*
 		 * The exception fixup table (might need resorting at runtime)
@@ -197,21 +174,10 @@ SECTIONS
 	}
 	_edata_loc = __data_loc + SIZEOF(.data);
 
-	.bss : {
-		__bss_start = .;	/* BSS				*/
-		*(.bss)
-		*(COMMON)
-		__bss_stop = .;
-		_end = .;
-	}
-					/* Stabs debugging sections.	*/
-	.stab 0 : { *(.stab) }
-	.stabstr 0 : { *(.stabstr) }
-	.stab.excl 0 : { *(.stab.excl) }
-	.stab.exclstr 0 : { *(.stab.exclstr) }
-	.stab.index 0 : { *(.stab.index) }
-	.stab.indexstr 0 : { *(.stab.indexstr) }
-	.comment 0 : { *(.comment) }
+	BSS_SECTION(0, 0, 0)
+	_end = .;
+
+	STABS_DEBUG
 }
 
 /*
-- 
1.6.3.3

Re: [PATCH v2 2/2] arm: Clean up linker script using new linker script macros.

[Russell King - ARM Linux]

On Wed, Sep 16, 2009 at 12:39:55PM -0400, Tim Abbott wrote:
> This patch is mostly a straightforward translation. The primary side
> effect to the resulting vmlinux should be to increase the alignment on
> the initramfs to the standard PAGE_SIZE from 32 bytes.

I notice you're not sending this to the ARM lists, which means it's
not getting a full review (eg, by Nico who knows the XIP issues in
here).  Are you sure this is correct for both the XIP and non-XIP
cases?

Re: [PATCH v2 2/2] arm: Clean up linker script using new linker script macros.

[Tim Abbott]

On Wed, 16 Sep 2009, Russell King - ARM Linux wrote:

> On Wed, Sep 16, 2009 at 12:39:55PM -0400, Tim Abbott wrote:
> > This patch is mostly a straightforward translation. The primary side
> > effect to the resulting vmlinux should be to increase the alignment on
> > the initramfs to the standard PAGE_SIZE from 32 bytes.
> 
> I notice you're not sending this to the ARM lists, which means it's
> not getting a full review (eg, by Nico who knows the XIP issues in
> here).  Are you sure this is correct for both the XIP and non-XIP
> cases?

I can resend to the ARM lists if it will work -- I didn't do so this time 
because I seem to recall that only subscribers can post; maybe I 
misunderstood the MAINTAINERS entry?

L:      linux-arm-kernel@lists.arm.linux.org.uk (subscribers-only)

Looking at the code, there's definitely something wrong in relation to 
CONFIG_XIP_KERNEL; I'll fix this and repost CCing 
linux-arm-kernel@lists.arm.linux.org.uk.

	-Tim Abbott

Re: [PATCH v2 2/2] arm: Clean up linker script using new linker script macros.

[Russell King - ARM Linux]

On Wed, Sep 16, 2009 at 03:31:37PM -0400, Tim Abbott wrote:
> I can resend to the ARM lists if it will work -- I didn't do so this time 
> because I seem to recall that only subscribers can post; maybe I 
> misunderstood the MAINTAINERS entry?
> 
> L:      linux-arm-kernel@lists.arm.linux.org.uk (subscribers-only)
> 
> Looking at the code, there's definitely something wrong in relation to 
> CONFIG_XIP_KERNEL; I'll fix this and repost CCing 
> linux-arm-kernel@lists.arm.linux.org.uk.

Please use linux-arm-kernel@lists.infradead.org instead.  (We'll
get the patch updating MAINTAINERS in soon.)