[PATCH 6.1 379/600] powerpc/pseries: Fix hcall tracepoints with JUMP_LABEL=n

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6.1-stable review patch.  If anyone has any objections, please let me know.

------------------

From: Nicholas Piggin <npiggin@xxxxxxxxx>

[ Upstream commit 750bd41aeaeb1f0e0128aa4f8fcd6dd759713641 ]

With JUMP_LABEL=n, hcall_tracepoint_refcount's address is being tested
instead of its value. This results in the tracing slowpath always being
taken unnecessarily.

Fixes: 9a10ccb29c0a2 ("powerpc/pseries: move hcall_tracepoint_refcount out of .toc")
Signed-off-by: Nicholas Piggin <npiggin@xxxxxxxxx>
Signed-off-by: Michael Ellerman <mpe@xxxxxxxxxxxxxx>
Link: https://msgid.link/20230509091600.70994-1-npiggin@xxxxxxxxx
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
 arch/powerpc/platforms/pseries/hvCall.S | 1 +
 1 file changed, 1 insertion(+)

diff --git a/arch/powerpc/platforms/pseries/hvCall.S b/arch/powerpc/platforms/pseries/hvCall.S
index 762eb15d3bd42..fc50b9c27c1ba 100644
--- a/arch/powerpc/platforms/pseries/hvCall.S
+++ b/arch/powerpc/platforms/pseries/hvCall.S
@@ -89,6 +89,7 @@ BEGIN_FTR_SECTION;						\
 	b	1f;						\
 END_FTR_SECTION(0, 1);						\
 	LOAD_REG_ADDR(r12, hcall_tracepoint_refcount) ;		\
+	ld	r12,0(r12);					\
 	std	r12,32(r1);					\
 	cmpdi	r12,0;						\
 	bne-	LABEL;						\
-- 
2.40.1






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