[PATCH 075/133] ARM: use linker magic for vectors and vector stubs

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

 



3.8.13.7 -stable review patch.  If anyone has any objections, please let me know.

------------------

From: Russell King <rmk+kernel@xxxxxxxxxxxxxxxx>

commit b9b32bf70f2fb710b07c94e13afbc729afe221da upstream.

Use linker magic to create the vectors and vector stubs: we can tell the
linker to place them at an appropriate VMA, but keep the LMA within the
kernel.  This gets rid of some unnecessary symbol manipulation, and
have the linker calculate the relocations appropriately.

Acked-by: Nicolas Pitre <nico@xxxxxxxxxx>
Signed-off-by: Russell King <rmk+kernel@xxxxxxxxxxxxxxxx>
Signed-off-by: Kamal Mostafa <kamal@xxxxxxxxxxxxx>
---
 arch/arm/kernel/entry-armv.S  | 28 ++++++++++------------------
 arch/arm/kernel/vmlinux.lds.S | 17 +++++++++++++++++
 2 files changed, 27 insertions(+), 18 deletions(-)

diff --git a/arch/arm/kernel/entry-armv.S b/arch/arm/kernel/entry-armv.S
index a4af8e8..c19779f 100644
--- a/arch/arm/kernel/entry-armv.S
+++ b/arch/arm/kernel/entry-armv.S
@@ -1035,7 +1035,7 @@ ENDPROC(vector_\name)
 1:
 	.endm
 
-	.globl	__stubs_start
+	.section .stubs, "ax", %progbits
 __stubs_start:
 	@ This must be the first word
 	.word	vector_swi
@@ -1162,24 +1162,16 @@ vector_addrexcptn:
 vector_fiq:
 	subs	pc, lr, #4
 
-	.globl	__stubs_end
-__stubs_end:
-
-	.equ	stubs_offset, __vectors_start + 0x1000 - __stubs_start
-
-	.globl	__vectors_start
+	.section .vectors, "ax", %progbits
 __vectors_start:
-	W(b)	vector_rst + stubs_offset
-	W(b)	vector_und + stubs_offset
-	W(ldr)	pc, .LCvswi + stubs_offset
-	W(b)	vector_pabt + stubs_offset
-	W(b)	vector_dabt + stubs_offset
-	W(b)	vector_addrexcptn + stubs_offset
-	W(b)	vector_irq + stubs_offset
-	W(b)	vector_fiq + stubs_offset
-
-	.globl	__vectors_end
-__vectors_end:
+	W(b)	vector_rst
+	W(b)	vector_und
+	W(ldr)	pc, __vectors_start + 0x1000
+	W(b)	vector_pabt
+	W(b)	vector_dabt
+	W(b)	vector_addrexcptn
+	W(b)	vector_irq
+	W(b)	vector_fiq
 
 	.data
 
diff --git a/arch/arm/kernel/vmlinux.lds.S b/arch/arm/kernel/vmlinux.lds.S
index 11c1785..f9036ac 100644
--- a/arch/arm/kernel/vmlinux.lds.S
+++ b/arch/arm/kernel/vmlinux.lds.S
@@ -148,6 +148,23 @@ SECTIONS
 	. = ALIGN(PAGE_SIZE);
 	__init_begin = .;
 #endif
+	/*
+	 * The vectors and stubs are relocatable code, and the
+	 * only thing that matters is their relative offsets
+	 */
+	__vectors_start = .;
+	.vectors 0 : AT(__vectors_start) {
+		*(.vectors)
+	}
+	. = __vectors_start + SIZEOF(.vectors);
+	__vectors_end = .;
+
+	__stubs_start = .;
+	.stubs 0x1000 : AT(__stubs_start) {
+		*(.stubs)
+	}
+	. = __stubs_start + SIZEOF(.stubs);
+	__stubs_end = .;
 
 	INIT_TEXT_SECTION(8)
 	.exit.text : {
-- 
1.8.1.2

--
To unsubscribe from this list: send the line "unsubscribe stable" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at  http://vger.kernel.org/majordomo-info.html




[Index of Archives]     [Linux Kernel]     [Kernel Development Newbies]     [Linux USB Devel]     [Video for Linux]     [Linux Audio Users]     [Yosemite Hiking]     [Linux Kernel]     [Linux SCSI]