FP is disabled for ARC and even if it was enabled, it won't help with
unwinding given ARC ABI so remove it.
Typical ABI would
- save BLINK (return address) on stack
- save FP on stack
- anchor FP for this frame
- save any callee-regs and/or carve frame for local vars
Thus FP remains fixed for frame and can be used to determine BLINK.
ARC ABI historically required saving callee-regs before anchoring FP,
thus rendering it useless for finding BLINK.
Signed-off-by: Vineet Gupta <vgu...@synopsys.com>
---
arch/arc/include/asm/unwind.h | 11 +----------
arch/arc/kernel/unwind.c | 45 ++-----------------------------------------
2 files changed, 3 insertions(+), 53 deletions(-)
diff --git a/arch/arc/include/asm/unwind.h b/arch/arc/include/asm/unwind.h
index 559ef55abce1..03ace2cc8bc5 100644
--- a/arch/arc/include/asm/unwind.h
+++ b/arch/arc/include/asm/unwind.h
@@ -58,17 +58,7 @@ struct unwind_frame_info {
#define UNW_PC(frame) ((frame)->regs.r63)
#define UNW_SP(frame) ((frame)->regs.r28)
#define UNW_BLINK(frame) ((frame)->regs.r31)
-
-/* Rajesh FIXME */
-#ifdef CONFIG_FRAME_POINTER
#define UNW_FP(frame) ((frame)->regs.r27)
-#define FRAME_RETADDR_OFFSET 4
-#define FRAME_LINK_OFFSET 0
-#define STACK_BOTTOM_UNW(tsk) STACK_LIMIT((tsk)->thread.ksp)
-#define STACK_TOP_UNW(tsk) ((tsk)->thread.ksp)
-#else
-#define UNW_FP(frame) ((void)(frame), 0)
-#endif
#define STACK_LIMIT(ptr) (((ptr) - 1) & ~(THREAD_SIZE - 1))
@@ -128,6 +118,7 @@ extern void unwind_remove_table(void *handle, int
init_only);
#define UNW_PC(frame) ((void)(frame), 0)
#define UNW_SP(frame) ((void)(frame), 0)
#define UNW_FP(frame) ((void)(frame), 0)
+#define UNW_FP(frame) ((void)(frame), 0)
static inline void arc_unwind_init(void)
{
diff --git a/arch/arc/kernel/unwind.c b/arch/arc/kernel/unwind.c
index 2f4a67f5a863..0993a81e112b 100644
--- a/arch/arc/kernel/unwind.c
+++ b/arch/arc/kernel/unwind.c
@@ -1057,50 +1057,9 @@ int arc_unwind(struct unwind_frame_info *frame)
fde = NULL;
}
}
- if (cie == NULL || fde == NULL) {
-#ifdef CONFIG_FRAME_POINTER
- unsigned long top, bottom;
-
- top = STACK_TOP_UNW(frame->task);
- bottom = STACK_BOTTOM_UNW(frame->task);
-#if FRAME_RETADDR_OFFSET < 0
- if (UNW_SP(frame) < top && UNW_FP(frame) <= UNW_SP(frame)
- && bottom < UNW_FP(frame)
-#else
- if (UNW_SP(frame) > top && UNW_FP(frame) >= UNW_SP(frame)
- && bottom > UNW_FP(frame)
-#endif
- && !((UNW_SP(frame) | UNW_FP(frame))
- & (sizeof(unsigned long) - 1))) {
- unsigned long link;
-
- if (!__get_user(link, (unsigned long *)
- (UNW_FP(frame) + FRAME_LINK_OFFSET))
-#if FRAME_RETADDR_OFFSET < 0
- && link > bottom && link < UNW_FP(frame)
-#else
- && link > UNW_FP(frame) && link < bottom
-#endif
- && !(link & (sizeof(link) - 1))
- && !__get_user(UNW_PC(frame),
- (unsigned long *)(UNW_FP(frame)
- + FRAME_RETADDR_OFFSET)))
- {
- UNW_SP(frame) =
- UNW_FP(frame) + FRAME_RETADDR_OFFSET
-#if FRAME_RETADDR_OFFSET < 0
- -
-#else
- +
-#endif
- sizeof(UNW_PC(frame));
- UNW_FP(frame) = link;
- return 0;
- }
- }
-#endif
+ if (cie == NULL || fde == NULL)
return -ENXIO;
- }
+
state.org = startLoc;
memcpy(&state.cfa, &badCFA, sizeof(state.cfa));
--
1.9.1
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