Patch c49f63530bb6 ("powernv: Add OPAL tracepoints") has a spurious
store to the stack:

        ld      r12,opal_tracepoint_refcount@toc(r2);           \
        std     r12,32(r1);                                     \

The store was originally used to save the current tracepoint status
so the entry and the exit tracepoints were always balanced. In the
end I just created a separate path when tracepoints are enabled.

The offset on the stack used for this store is not valid for ABIv2
and it causes strange issues. I noticed it because OPAL console input
was broken.

Fixes: c49f63530bb6 ("powernv: Add OPAL tracepoints")
Cc: <sta...@vger.kernel.org> # v3.17+
Signed-off-by: Anton Blanchard <an...@samba.org>
---
 arch/powerpc/platforms/powernv/opal-wrappers.S | 1 -
 1 file changed, 1 deletion(-)

diff --git a/arch/powerpc/platforms/powernv/opal-wrappers.S 
b/arch/powerpc/platforms/powernv/opal-wrappers.S
index 54eca8b..0509bca 100644
--- a/arch/powerpc/platforms/powernv/opal-wrappers.S
+++ b/arch/powerpc/platforms/powernv/opal-wrappers.S
@@ -40,7 +40,6 @@ BEGIN_FTR_SECTION;                                            
\
        b       1f;                                             \
 END_FTR_SECTION(0, 1);                                         \
        ld      r12,opal_tracepoint_refcount@toc(r2);           \
-       std     r12,32(r1);                                     \
        cmpdi   r12,0;                                          \
        bne-    LABEL;                                          \
 1:
-- 
2.1.0

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