From mboxrd@z Thu Jan 1 00:00:00 1970 From: dave.martin@linaro.org (Dave Martin) Date: Thu, 1 Nov 2012 15:01:41 +0100 Subject: [PATCH] ARM: stacktrace: Fix return_address() for CONFIG_FRAME_POINTER Message-ID: <1351778501-29924-1-git-send-email-dave.martin@linaro.org> To: linux-arm-kernel@lists.infradead.org List-Id: linux-arm-kernel.lists.infradead.org return_address() currently relies on walk_stackframe() setting frame->lr, but walk_stackframe() never sets this field. Setting frame->lr from walk_stackframe() would require walk_stackframe() to unwind one frame beyond the frame being returned, and to track extra state in struct stackframe. The value of this is debatable, so this patch modifies caller_address() to unwind one extra level explicitly and reference frame->pc instead of frame->lr. Signed-off-by: Dave Martin --- arch/arm/kernel/return_address.c | 4 ++-- 1 files changed, 2 insertions(+), 2 deletions(-) diff --git a/arch/arm/kernel/return_address.c b/arch/arm/kernel/return_address.c index 8085417..0854b54 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 +41,7 @@ void *return_address(unsigned int level) struct stackframe frame; register unsigned long current_sp asm ("sp"); - data.level = level + 1; + data.level = level + 2; frame.fp = (unsigned long)__builtin_frame_address(0); frame.sp = current_sp; -- 1.7.5.4