[U-Boot] [PATCH v2] ARM: Align stack to 8 bytes

Vitaly Kuzmichev vkuzmichev at mvista.com
Tue Jun 15 20:18:11 CEST 2010


The ARM ABI requires that the stack be aligned to 8 bytes as it is noted
in Procedure Call Standard for the ARM Architecture:
http://infocenter.arm.com/help/topic/com.arm.doc.ihi0042d/index.html

Unaligned SP also causes the problem with variable-length arrays
allocation when VLA address becomes less than stack pointer during
aligning of this address, so the next 'push' in the stack overwrites
first 4 bytes of VLA.

Signed-off-by: Vitaly Kuzmichev <vkuzmichev at mvista.com>
---
 arch/arm/cpu/arm1136/start.S      |    1 +
 arch/arm/cpu/arm1176/start.S      |    1 +
 arch/arm/cpu/arm720t/start.S      |    1 +
 arch/arm/cpu/arm920t/start.S      |    1 +
 arch/arm/cpu/arm925t/start.S      |    1 +
 arch/arm/cpu/arm926ejs/start.S    |    2 +-
 arch/arm/cpu/arm946es/start.S     |    1 +
 arch/arm/cpu/arm_cortexa8/start.S |    2 +-
 arch/arm/cpu/arm_intcm/start.S    |    1 +
 arch/arm/cpu/ixp/start.S          |    1 +
 arch/arm/cpu/lh7a40x/start.S      |    1 +
 arch/arm/cpu/pxa/start.S          |    1 +
 arch/arm/cpu/s3c44b0/start.S      |    1 +
 arch/arm/cpu/sa1100/start.S       |    1 +
 14 files changed, 14 insertions(+), 2 deletions(-)

diff --git a/arch/arm/cpu/arm1136/start.S b/arch/arm/cpu/arm1136/start.S
index 957f438..f0cb3cc 100644
--- a/arch/arm/cpu/arm1136/start.S
+++ b/arch/arm/cpu/arm1136/start.S
@@ -185,6 +185,7 @@ stack_setup:
 #endif
 	sub	sp, r0, #12		/* leave 3 words for abort-stack    */
 #endif	/* CONFIG_PRELOADER */
+	bic	sp, sp, #7		/* 8-byte alignment for ABI compliance */
 
 clear_bss:
 	ldr	r0, _bss_start		/* find start of bss segment	    */
diff --git a/arch/arm/cpu/arm1176/start.S b/arch/arm/cpu/arm1176/start.S
index e2b6c9b..2162a6b 100644
--- a/arch/arm/cpu/arm1176/start.S
+++ b/arch/arm/cpu/arm1176/start.S
@@ -249,6 +249,7 @@ stack_setup:
 	sub	r0, r0, #CONFIG_SYS_MALLOC_LEN	/* malloc area                      */
 	sub	r0, r0, #CONFIG_SYS_GBL_DATA_SIZE /* bdinfo                        */
 	sub	sp, r0, #12		/* leave 3 words for abort-stack    */
+	bic	sp, sp, #7		/* 8-byte alignment for ABI compliance */
 
 clear_bss:
 	ldr	r0, _bss_start		/* find start of bss segment        */
diff --git a/arch/arm/cpu/arm720t/start.S b/arch/arm/cpu/arm720t/start.S
index 022b873..d6f2c16 100644
--- a/arch/arm/cpu/arm720t/start.S
+++ b/arch/arm/cpu/arm720t/start.S
@@ -172,6 +172,7 @@ stack_setup:
 	sub	r0, r0, #(CONFIG_STACKSIZE_IRQ+CONFIG_STACKSIZE_FIQ)
 #endif
 	sub	sp, r0, #12		/* leave 3 words for abort-stack    */
+	bic	sp, sp, #7		/* 8-byte alignment for ABI compliance */
 
 clear_bss:
 	ldr	r0, _bss_start		/* find start of bss segment	    */
diff --git a/arch/arm/cpu/arm920t/start.S b/arch/arm/cpu/arm920t/start.S
index 779f192..e532f55 100644
--- a/arch/arm/cpu/arm920t/start.S
+++ b/arch/arm/cpu/arm920t/start.S
@@ -204,6 +204,7 @@ stack_setup:
 	sub	r0, r0, #(CONFIG_STACKSIZE_IRQ+CONFIG_STACKSIZE_FIQ)
 #endif
 	sub	sp, r0, #12		/* leave 3 words for abort-stack    */
+	bic	sp, sp, #7		/* 8-byte alignment for ABI compliance */
 
 clear_bss:
 	ldr	r0, _bss_start		/* find start of bss segment        */
diff --git a/arch/arm/cpu/arm925t/start.S b/arch/arm/cpu/arm925t/start.S
index 567e804..346615e 100644
--- a/arch/arm/cpu/arm925t/start.S
+++ b/arch/arm/cpu/arm925t/start.S
@@ -196,6 +196,7 @@ stack_setup:
 	sub	r0, r0, #(CONFIG_STACKSIZE_IRQ+CONFIG_STACKSIZE_FIQ)
 #endif
 	sub	sp, r0, #12		/* leave 3 words for abort-stack    */
+	bic	sp, sp, #7		/* 8-byte alignment for ABI compliance */
 
 clear_bss:
 	ldr	r0, _bss_start		/* find start of bss segment        */
diff --git a/arch/arm/cpu/arm926ejs/start.S b/arch/arm/cpu/arm926ejs/start.S
index 3b81151..cf40ce1 100644
--- a/arch/arm/cpu/arm926ejs/start.S
+++ b/arch/arm/cpu/arm926ejs/start.S
@@ -196,7 +196,7 @@ stack_setup:
 #endif
 #endif /* CONFIG_PRELOADER */
 	sub	sp, r0, #12		/* leave 3 words for abort-stack    */
-	bic	sp, r0, #7		/* 8-byte align stack for ABI compliance */
+	bic	sp, sp, #7		/* 8-byte alignment for ABI compliance */
 
 clear_bss:
 	ldr	r0, _bss_start		/* find start of bss segment        */
diff --git a/arch/arm/cpu/arm946es/start.S b/arch/arm/cpu/arm946es/start.S
index 627e3cb..8844d44 100644
--- a/arch/arm/cpu/arm946es/start.S
+++ b/arch/arm/cpu/arm946es/start.S
@@ -163,6 +163,7 @@ stack_setup:
 	sub	r0, r0, #(CONFIG_STACKSIZE_IRQ+CONFIG_STACKSIZE_FIQ)
 #endif
 	sub	sp, r0, #12		/* leave 3 words for abort-stack    */
+	bic	sp, sp, #7		/* 8-byte alignment for ABI compliance */
 
 clear_bss:
 	ldr	r0, _bss_start		/* find start of bss segment        */
diff --git a/arch/arm/cpu/arm_cortexa8/start.S b/arch/arm/cpu/arm_cortexa8/start.S
index 29dae2f..1e0a150 100644
--- a/arch/arm/cpu/arm_cortexa8/start.S
+++ b/arch/arm/cpu/arm_cortexa8/start.S
@@ -164,7 +164,7 @@ stack_setup:
 	sub	r0, r0, #(CONFIG_STACKSIZE_IRQ + CONFIG_STACKSIZE_FIQ)
 #endif
 	sub	sp, r0, #12		@ leave 3 words for abort-stack
-	and	sp, sp, #~7		@ 8 byte alinged for (ldr/str)d
+	bic	sp, sp, #7		@ 8-byte alignment for ABI compliance
 
 	/* Clear BSS (if any). Is below tx (watch load addr - need space) */
 clear_bss:
diff --git a/arch/arm/cpu/arm_intcm/start.S b/arch/arm/cpu/arm_intcm/start.S
index bb1f003..328bae0 100644
--- a/arch/arm/cpu/arm_intcm/start.S
+++ b/arch/arm/cpu/arm_intcm/start.S
@@ -161,6 +161,7 @@ stack_setup:
 	sub	r0, r0, #(CONFIG_STACKSIZE_IRQ+CONFIG_STACKSIZE_FIQ)
 #endif
 	sub	sp, r0, #12		/* leave 3 words for abort-stack    */
+	bic	sp, sp, #7		/* 8-byte alignment for ABI compliance */
 
 clear_bss:
 	ldr	r0, _bss_start		/* find start of bss segment        */
diff --git a/arch/arm/cpu/ixp/start.S b/arch/arm/cpu/ixp/start.S
index 5ebce53..6efe333 100644
--- a/arch/arm/cpu/ixp/start.S
+++ b/arch/arm/cpu/ixp/start.S
@@ -289,6 +289,7 @@ stack_setup:
 	sub	r0, r0, #(CONFIG_STACKSIZE_IRQ+CONFIG_STACKSIZE_FIQ)
 #endif
 	sub	sp, r0, #12		/* leave 3 words for abort-stack    */
+	bic	sp, sp, #7		/* 8-byte alignment for ABI compliance */
 
 clear_bss:
 	ldr	r0, _bss_start		/* find start of bss segment        */
diff --git a/arch/arm/cpu/lh7a40x/start.S b/arch/arm/cpu/lh7a40x/start.S
index a1321b1..14a1fbe 100644
--- a/arch/arm/cpu/lh7a40x/start.S
+++ b/arch/arm/cpu/lh7a40x/start.S
@@ -178,6 +178,7 @@ stack_setup:
 	sub	r0, r0, #(CONFIG_STACKSIZE_IRQ+CONFIG_STACKSIZE_FIQ)
 #endif
 	sub	sp, r0, #12		/* leave 3 words for abort-stack    */
+	bic	sp, sp, #7		/* 8-byte alignment for ABI compliance */
 
 clear_bss:
 	ldr	r0, _bss_start		/* find start of bss segment        */
diff --git a/arch/arm/cpu/pxa/start.S b/arch/arm/cpu/pxa/start.S
index 63ab0c5..e07c8c2 100644
--- a/arch/arm/cpu/pxa/start.S
+++ b/arch/arm/cpu/pxa/start.S
@@ -141,6 +141,7 @@ stack_setup:
 	sub	r0, r0, #(CONFIG_STACKSIZE_IRQ+CONFIG_STACKSIZE_FIQ)
 #endif /* CONFIG_USE_IRQ */
 	sub	sp, r0, #12		/* leave 3 words for abort-stack    */
+	bic	sp, sp, #7		/* 8-byte alignment for ABI compliance */
 
 clear_bss:
 	ldr	r0, _bss_start		/* find start of bss segment	    */
diff --git a/arch/arm/cpu/s3c44b0/start.S b/arch/arm/cpu/s3c44b0/start.S
index f5a3d3a..0063063 100644
--- a/arch/arm/cpu/s3c44b0/start.S
+++ b/arch/arm/cpu/s3c44b0/start.S
@@ -163,6 +163,7 @@ stack_setup:
 	sub	r0, r0, #(CONFIG_STACKSIZE_IRQ+CONFIG_STACKSIZE_FIQ)
 #endif
 	sub	sp, r0, #12		/* leave 3 words for abort-stack    */
+	bic	sp, sp, #7		/* 8-byte alignment for ABI compliance */
 
 	ldr	pc, _start_armboot
 
diff --git a/arch/arm/cpu/sa1100/start.S b/arch/arm/cpu/sa1100/start.S
index 278c500..deb4745 100644
--- a/arch/arm/cpu/sa1100/start.S
+++ b/arch/arm/cpu/sa1100/start.S
@@ -153,6 +153,7 @@ stack_setup:
 	sub	r0, r0, #(CONFIG_STACKSIZE_IRQ+CONFIG_STACKSIZE_FIQ)
 #endif
 	sub	sp, r0, #12		/* leave 3 words for abort-stack    */
+	bic	sp, sp, #7		/* 8-byte alignment for ABI compliance */
 
 clear_bss:
 	ldr	r0, _bss_start		/* find start of bss segment        */
-- 
1.6.2.3.127.gb136



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