[PATCH] arm64: kcsan: Fix kcsan test_barrier fail and panic

[Kefeng Wang]

As "kcsan: Support detecting a subset of missing memory barriers"
introduced KCSAN_STRICT which make kcsan detects more missing memory
barrier, but arm64 don't have KCSAN instrumentation for barriers, so
the new selftest test_barrier() will fail, then panic.

Let's prefix all barriers with __ on arm64, as asm-generic/barriers.h
defined the final instrumented version of these barriers, which will
fix the above issues.

Fixes: dd03762ab608 ("arm64: Enable KCSAN")
Signed-off-by: Kefeng Wang <wangkefeng.wang@xxxxxxxxxx>
---
 arch/arm64/include/asm/barrier.h | 12 ++++++------
 include/asm-generic/barrier.h    |  4 ++++
 2 files changed, 10 insertions(+), 6 deletions(-)

diff --git a/arch/arm64/include/asm/barrier.h b/arch/arm64/include/asm/barrier.h
index 62217be36217..9760a8d4ed0a 100644
--- a/arch/arm64/include/asm/barrier.h
+++ b/arch/arm64/include/asm/barrier.h
@@ -46,13 +46,13 @@
 #define pmr_sync()	do {} while (0)
 #endif
 
-#define mb()		dsb(sy)
-#define rmb()		dsb(ld)
-#define wmb()		dsb(st)
+#define __mb()		dsb(sy)
+#define __rmb()		dsb(ld)
+#define __wmb()		dsb(st)
 
-#define dma_mb()	dmb(osh)
-#define dma_rmb()	dmb(oshld)
-#define dma_wmb()	dmb(oshst)
+#define __dma_mb()	dmb(osh)
+#define __dma_rmb()	dmb(oshld)
+#define __dma_wmb()	dmb(oshst)
 
 #define io_stop_wc()	dgh()
 
diff --git a/include/asm-generic/barrier.h b/include/asm-generic/barrier.h
index fd7e8fbaeef1..18863c50e9ce 100644
--- a/include/asm-generic/barrier.h
+++ b/include/asm-generic/barrier.h
@@ -38,6 +38,10 @@
 #define wmb()	do { kcsan_wmb(); __wmb(); } while (0)
 #endif
 
+#ifdef __dma_mb
+#define dma_mb()	do { kcsan_mb(); __dma_mb(); } while (0)
+#endif
+
 #ifdef __dma_rmb
 #define dma_rmb()	do { kcsan_rmb(); __dma_rmb(); } while (0)
 #endif
-- 
2.27.0