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authorKeun-O Park <kpark3469@gmail.com>2013-03-18 07:32:53 +0100
committerRussell King <rmk+kernel@arm.linux.org.uk>2013-03-19 11:43:46 +0000
commit01223f365074d62bbc24709dad9b4a905206fa02 (patch)
tree46df5c9f31a33f8c590bae714fbc2b5ef8160d7e /arch/arm/kernel/return_address.c
parent3b4af9bc24472a9411837ad0794312028df1fbd9 (diff)
ARM: 7676/1: fix a wrong value returned from CALLER_ADDRn
This makes return_address() return a correct value for CALLER_ADDRn. To have a correct value from CALLER_ADDRn, we need to fix three points. * The unwind_frame() does not update frame->lr but frame->pc for backtrace. So frame->pc is meaningful for backtrace. * data.level should be adjusted by adding 2 additional iteration levels. With the current +1 level adjustment, the result of CALLER_ADDR1 will be the same return address with CALLER_ADDR0. * The initialization of data.addr to NULL is needed. When unwind_fame() fails right after data.level reaches zero, the routine returns data.addr which has uninitialized garbage value. Signed-off-by: Sahara <keun-o.park@windriver.com> Reviewed-by: Dave Martin <dave.martin@linaro.org> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Diffstat (limited to 'arch/arm/kernel/return_address.c')
-rw-r--r--arch/arm/kernel/return_address.c5
1 files changed, 3 insertions, 2 deletions
diff --git a/arch/arm/kernel/return_address.c b/arch/arm/kernel/return_address.c
index 8085417555dd..fafedd86885d 100644
--- a/arch/arm/kernel/return_address.c
+++ b/arch/arm/kernel/return_address.c
@@ -26,7 +26,7 @@ static int save_return_addr(struct stackframe *frame, void *d)
struct return_address_data *data = d;
if (!data->level) {
- data->addr = (void *)frame->lr;
+ data->addr = (void *)frame->pc;
return 1;
} else {
@@ -41,7 +41,8 @@ void *return_address(unsigned int level)
struct stackframe frame;
register unsigned long current_sp asm ("sp");
- data.level = level + 1;
+ data.level = level + 2;
+ data.addr = NULL;
frame.fp = (unsigned long)__builtin_frame_address(0);
frame.sp = current_sp;