[PATCH 01/13] selftests/powerpc: Ensure 16-byte stack pointer alignment
Michael Ellerman
mpe at ellerman.id.au
Tue Jun 28 00:02:27 AEST 2022
The PUSH/POP_BASIC_STACK helpers in basic_asm.h do not ensure that the
stack pointer is always 16-byte aligned, which is required per the ABI.
Fix the macros to do the alignment if the caller fails to.
Currently only one caller passes a non-aligned size, tm_signal_self(),
which hasn't been caught in testing, presumably because it's a leaf
function.
Signed-off-by: Michael Ellerman <mpe at ellerman.id.au>
---
tools/testing/selftests/powerpc/include/basic_asm.h | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)
diff --git a/tools/testing/selftests/powerpc/include/basic_asm.h b/tools/testing/selftests/powerpc/include/basic_asm.h
index 886dc026fe7a..807e83e821ec 100644
--- a/tools/testing/selftests/powerpc/include/basic_asm.h
+++ b/tools/testing/selftests/powerpc/include/basic_asm.h
@@ -58,7 +58,7 @@
#define PUSH_BASIC_STACK(_extra) \
mflr r0; \
std r0, STACK_FRAME_LR_POS(%r1); \
- stdu %r1, -(_extra + STACK_FRAME_MIN_SIZE)(%r1); \
+ stdu %r1, -(((_extra + 15) & ~15) + STACK_FRAME_MIN_SIZE)(%r1); \
mfcr r0; \
stw r0, STACK_FRAME_CR_POS(%r1); \
std %r2, STACK_FRAME_TOC_POS(%r1);
@@ -67,7 +67,7 @@
ld %r2, STACK_FRAME_TOC_POS(%r1); \
lwz r0, STACK_FRAME_CR_POS(%r1); \
mtcr r0; \
- addi %r1, %r1, (_extra + STACK_FRAME_MIN_SIZE); \
+ addi %r1, %r1, (((_extra + 15) & ~15) + STACK_FRAME_MIN_SIZE); \
ld r0, STACK_FRAME_LR_POS(%r1); \
mtlr r0;
--
2.35.3
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