Commit 499b2ea1 authored by Nicolas Pitre's avatar Nicolas Pitre Committed by Russell King
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[ARM] 3103/1: ARM EABI: stack pointer must be 64-bit aligned (part 2) 



Patch from Nicolas Pitre

We must make sure that assembly code that modifies the stack pointer
before calling a C function does it so it remains 64-bit aligned.

Signed-off-by: default avatarNicolas Pitre <nico@cam.org>
Signed-off-by: default avatarRussell King <rmk+kernel@arm.linux.org.uk>
parent 2dede2d8

arch/arm/kernel/semaphore.c

+9 −8
Original line number Diff line number Diff line
@@ -177,41 +177,42 @@ int __down_trylock(struct semaphore * sem) 
 * ip contains the semaphore pointer on entry. Save the C-clobbered

 * registers (r0 to r3 and lr), but not ip, as we use it as a return

 * value in some cases..

 * To remain AAPCS compliant (64-bit stack align) we save r4 as well.

 */

asm("	.section .sched.text,\"ax\",%progbits	\n\

	.align	5				\n\

	.globl	__down_failed			\n\

__down_failed:					\n\

	stmfd	sp!, {r0 - r3, lr}		\n\

	stmfd	sp!, {r0 - r4, lr}		\n\

	mov	r0, ip				\n\

	bl	__down				\n\

	ldmfd	sp!, {r0 - r3, pc}		\n\

	ldmfd	sp!, {r0 - r4, pc}		\n\

						\n\

	.align	5				\n\

	.globl	__down_interruptible_failed	\n\

__down_interruptible_failed:			\n\

	stmfd	sp!, {r0 - r3, lr}		\n\

	stmfd	sp!, {r0 - r4, lr}		\n\

	mov	r0, ip				\n\

	bl	__down_interruptible		\n\

	mov	ip, r0				\n\

	ldmfd	sp!, {r0 - r3, pc}		\n\

	ldmfd	sp!, {r0 - r4, pc}		\n\

						\n\

	.align	5				\n\

	.globl	__down_trylock_failed		\n\

__down_trylock_failed:				\n\

	stmfd	sp!, {r0 - r3, lr}		\n\

	stmfd	sp!, {r0 - r4, lr}		\n\

	mov	r0, ip				\n\

	bl	__down_trylock			\n\

	mov	ip, r0				\n\

	ldmfd	sp!, {r0 - r3, pc}		\n\

	ldmfd	sp!, {r0 - r4, pc}		\n\

						\n\

	.align	5				\n\

	.globl	__up_wakeup			\n\

__up_wakeup:					\n\

	stmfd	sp!, {r0 - r3, lr}		\n\

	stmfd	sp!, {r0 - r4, lr}		\n\

	mov	r0, ip				\n\

	bl	__up				\n\

	ldmfd	sp!, {r0 - r3, pc}		\n\

	ldmfd	sp!, {r0 - r4, pc}		\n\

	");



EXPORT_SYMBOL(__down_failed);

arch/arm/lib/lib1funcs.S

+2 −2
Original line number Diff line number Diff line
@@ -306,9 +306,9 @@ ENTRY(__modsi3) 


Ldiv0:



	str	lr, [sp, #-4]!

	str	lr, [sp, #-8]!

	bl	__div0

	mov	r0, #0			@ About as wrong as it could be.

	ldr	pc, [sp], #4

	ldr	pc, [sp], #8