diff --git a/lib/tsan/CMakeLists.txt b/lib/tsan/CMakeLists.txt
index 4a2ea3f..d501d0c 100644
--- a/lib/tsan/CMakeLists.txt
+++ b/lib/tsan/CMakeLists.txt
@@ -158,6 +158,15 @@
         VERBATIM)
     elseif(arch STREQUAL "aarch64")
       add_asm_sources(TSAN_ASM_SOURCES rtl/tsan_rtl_aarch64.S)
+      # Sanity check for Go runtime.
+      set(BUILDGO_SCRIPT ${CMAKE_CURRENT_SOURCE_DIR}/go/buildgo.sh)
+      add_custom_target(GotsanRuntimeCheck
+	COMMAND env "CC=${CMAKE_C_COMPILER} ${CMAKE_C_COMPILER_ARG1}"
+		IN_TMPDIR=1 SILENT=1 ${BUILDGO_SCRIPT}
+	DEPENDS clang_rt.tsan-${arch} ${BUILDGO_SCRIPT}
+	WORKING_DIRECTORY ${CMAKE_CURRENT_SOURCE_DIR}/go
+	COMMENT "Checking TSan Go runtime..."
+	VERBATIM)
     elseif(arch MATCHES "powerpc64|powerpc64le")
       add_asm_sources(TSAN_ASM_SOURCES rtl/tsan_rtl_ppc64.S)
       # Sanity check for Go runtime.
diff --git a/lib/tsan/go/buildgo.sh b/lib/tsan/go/buildgo.sh
index 7f570ca..6f6183b 100755
--- a/lib/tsan/go/buildgo.sh
+++ b/lib/tsan/go/buildgo.sh
@@ -55,13 +55,19 @@
 		"
 	if [ "`uname -a | grep ppc64le`" != "" ]; then
 		SUFFIX="linux_ppc64le"
+		ARCHCFLAGS="-m64"
 	elif [ "`uname -a | grep x86_64`" != "" ]; then
 		SUFFIX="linux_amd64"
+		ARCHCFLAGS="-m64"
 		OSCFLAGS="$OSCFLAGS -ffreestanding -Wno-unused-const-variable -Werror -Wno-unknown-warning-option"
+	elif [ "`uname -a | grep aarch64`" != "" ]; then
+		SUFFIX="linux_arm64"
+		ARCHCFLAGS=""
 	fi
 elif [ "`uname -a | grep FreeBSD`" != "" ]; then
 	SUFFIX="freebsd_amd64"
 	OSCFLAGS="-fno-strict-aliasing -fPIC -Werror"
+	ARCHCFLAGS="-m64"
 	OSLDFLAGS="-lpthread -fPIC -fpie"
 	SRCS="
 		$SRCS
@@ -77,6 +83,7 @@
 elif [ "`uname -a | grep NetBSD`" != "" ]; then
 	SUFFIX="netbsd_amd64"
 	OSCFLAGS="-fno-strict-aliasing -fPIC -Werror"
+	ARCHCFLAGS="-m64"
 	OSLDFLAGS="-lpthread -fPIC -fpie"
 	SRCS="
 		$SRCS
@@ -92,6 +99,7 @@
 elif [ "`uname -a | grep Darwin`" != "" ]; then
 	SUFFIX="darwin_amd64"
 	OSCFLAGS="-fPIC -Wno-unused-const-variable -Wno-unknown-warning-option -mmacosx-version-min=10.7"
+	ARCHCFLAGS="-m64"
 	OSLDFLAGS="-lpthread -fPIC -fpie -mmacosx-version-min=10.7"
 	SRCS="
 		$SRCS
@@ -104,6 +112,7 @@
 elif [ "`uname -a | grep MINGW`" != "" ]; then
 	SUFFIX="windows_amd64"
 	OSCFLAGS="-Wno-error=attributes -Wno-attributes -Wno-unused-const-variable -Wno-unknown-warning-option"
+	ARCHCFLAGS="-m64"
 	OSLDFLAGS=""
 	SRCS="
 		$SRCS
@@ -136,7 +145,7 @@
 	cat $F >> $DIR/gotsan.cc
 done
 
-FLAGS=" -I../rtl -I../.. -I../../sanitizer_common -I../../../include -std=c++11 -m64 -Wall -fno-exceptions -fno-rtti -DSANITIZER_GO=1 -DSANITIZER_DEADLOCK_DETECTOR_VERSION=2 $OSCFLAGS"
+FLAGS=" -I../rtl -I../.. -I../../sanitizer_common -I../../../include -std=c++11 -Wall -fno-exceptions -fno-rtti -DSANITIZER_GO=1 -DSANITIZER_DEADLOCK_DETECTOR_VERSION=2 $OSCFLAGS $ARCHCFLAGS"
 if [ "$DEBUG" = "" ]; then
 	FLAGS="$FLAGS -DSANITIZER_DEBUG=0 -O3 -fomit-frame-pointer"
 	if [ "$SUFFIX" = "linux_ppc64le" ]; then
@@ -153,7 +162,7 @@
 fi
 $CC $DIR/gotsan.cc -c -o $DIR/race_$SUFFIX.syso $FLAGS $CFLAGS
 
-$CC $OSCFLAGS test.c $DIR/race_$SUFFIX.syso -m64 -g -o $DIR/test $OSLDFLAGS $LDFLAGS
+$CC $OSCFLAGS $ARCHCFLAGS test.c $DIR/race_$SUFFIX.syso -g -o $DIR/test $OSLDFLAGS $LDFLAGS
 
 export GORACE="exitcode=0 atexit_sleep_ms=0"
 if [ "$SILENT" != "1" ]; then
diff --git a/lib/tsan/rtl/tsan_platform.h b/lib/tsan/rtl/tsan_platform.h
index 6b3e6ba..70ae617 100644
--- a/lib/tsan/rtl/tsan_platform.h
+++ b/lib/tsan/rtl/tsan_platform.h
@@ -458,6 +458,32 @@
   static const uptr kAppMemEnd     = 0x00e000000000ull;
 };
 
+#elif SANITIZER_GO && defined(__aarch64__)
+
+/* Go on linux/aarch64 (48-bit VMA)
+0000 0000 1000 - 0000 1000 0000: executable
+0000 1000 0000 - 00c0 0000 0000: -
+00c0 0000 0000 - 00e0 0000 0000: heap
+00e0 0000 0000 - 2000 0000 0000: -
+2000 0000 0000 - 3000 0000 0000: shadow
+3000 0000 0000 - 3000 0000 0000: -
+3000 0000 0000 - 4000 0000 0000: metainfo (memory blocks and sync objects)
+4000 0000 0000 - 6000 0000 0000: -
+6000 0000 0000 - 6200 0000 0000: traces
+6200 0000 0000 - 8000 0000 0000: -
+*/
+
+struct Mapping48 {
+  static const uptr kMetaShadowBeg = 0x300000000000ull;
+  static const uptr kMetaShadowEnd = 0x400000000000ull;
+  static const uptr kTraceMemBeg   = 0x600000000000ull;
+  static const uptr kTraceMemEnd   = 0x620000000000ull;
+  static const uptr kShadowBeg     = 0x200000000000ull;
+  static const uptr kShadowEnd     = 0x300000000000ull;
+  static const uptr kAppMemBeg     = 0x000000001000ull;
+  static const uptr kAppMemEnd     = 0x00e000000000ull;
+};
+
 // Indicates the runtime will define the memory regions at runtime.
 #define TSAN_RUNTIME_VMA 1
 
@@ -525,8 +551,10 @@
 uptr MappingArchImpl(void) {
 #if defined(__aarch64__) && !defined(__APPLE__)
   switch (vmaSize) {
+#if !SANITIZER_GO
     case 39: return MappingImpl<Mapping39, Type>();
     case 42: return MappingImpl<Mapping42, Type>();
+#endif
     case 48: return MappingImpl<Mapping48, Type>();
   }
   DCHECK(0);
@@ -682,8 +710,10 @@
 bool IsAppMem(uptr mem) {
 #if defined(__aarch64__) && !defined(__APPLE__)
   switch (vmaSize) {
+#if !SANITIZER_GO
     case 39: return IsAppMemImpl<Mapping39>(mem);
     case 42: return IsAppMemImpl<Mapping42>(mem);
+#endif
     case 48: return IsAppMemImpl<Mapping48>(mem);
   }
   DCHECK(0);
@@ -713,8 +743,10 @@
 bool IsShadowMem(uptr mem) {
 #if defined(__aarch64__) && !defined(__APPLE__)
   switch (vmaSize) {
+#if !SANITIZER_GO
     case 39: return IsShadowMemImpl<Mapping39>(mem);
     case 42: return IsShadowMemImpl<Mapping42>(mem);
+#endif
     case 48: return IsShadowMemImpl<Mapping48>(mem);
   }
   DCHECK(0);
@@ -744,8 +776,10 @@
 bool IsMetaMem(uptr mem) {
 #if defined(__aarch64__) && !defined(__APPLE__)
   switch (vmaSize) {
+#if !SANITIZER_GO
     case 39: return IsMetaMemImpl<Mapping39>(mem);
     case 42: return IsMetaMemImpl<Mapping42>(mem);
+#endif
     case 48: return IsMetaMemImpl<Mapping48>(mem);
   }
   DCHECK(0);
@@ -785,8 +819,10 @@
 uptr MemToShadow(uptr x) {
 #if defined(__aarch64__) && !defined(__APPLE__)
   switch (vmaSize) {
+#if !SANITIZER_GO
     case 39: return MemToShadowImpl<Mapping39>(x);
     case 42: return MemToShadowImpl<Mapping42>(x);
+#endif
     case 48: return MemToShadowImpl<Mapping48>(x);
   }
   DCHECK(0);
@@ -828,8 +864,10 @@
 u32 *MemToMeta(uptr x) {
 #if defined(__aarch64__) && !defined(__APPLE__)
   switch (vmaSize) {
+#if !SANITIZER_GO
     case 39: return MemToMetaImpl<Mapping39>(x);
     case 42: return MemToMetaImpl<Mapping42>(x);
+#endif
     case 48: return MemToMetaImpl<Mapping48>(x);
   }
   DCHECK(0);
@@ -884,8 +922,10 @@
 uptr ShadowToMem(uptr s) {
 #if defined(__aarch64__) && !defined(__APPLE__)
   switch (vmaSize) {
+#if !SANITIZER_GO
     case 39: return ShadowToMemImpl<Mapping39>(s);
     case 42: return ShadowToMemImpl<Mapping42>(s);
+#endif
     case 48: return ShadowToMemImpl<Mapping48>(s);
   }
   DCHECK(0);
@@ -923,8 +963,10 @@
 uptr GetThreadTrace(int tid) {
 #if defined(__aarch64__) && !defined(__APPLE__)
   switch (vmaSize) {
+#if !SANITIZER_GO
     case 39: return GetThreadTraceImpl<Mapping39>(tid);
     case 42: return GetThreadTraceImpl<Mapping42>(tid);
+#endif
     case 48: return GetThreadTraceImpl<Mapping48>(tid);
   }
   DCHECK(0);
@@ -957,8 +999,10 @@
 uptr GetThreadTraceHeader(int tid) {
 #if defined(__aarch64__) && !defined(__APPLE__)
   switch (vmaSize) {
+#if !SANITIZER_GO
     case 39: return GetThreadTraceHeaderImpl<Mapping39>(tid);
     case 42: return GetThreadTraceHeaderImpl<Mapping42>(tid);
+#endif
     case 48: return GetThreadTraceHeaderImpl<Mapping48>(tid);
   }
   DCHECK(0);
diff --git a/lib/tsan/rtl/tsan_platform_linux.cc b/lib/tsan/rtl/tsan_platform_linux.cc
index de989b7..d2ce607 100644
--- a/lib/tsan/rtl/tsan_platform_linux.cc
+++ b/lib/tsan/rtl/tsan_platform_linux.cc
@@ -212,11 +212,19 @@
   vmaSize =
     (MostSignificantSetBitIndex(GET_CURRENT_FRAME()) + 1);
 #if defined(__aarch64__)
+# if !SANITIZER_GO
   if (vmaSize != 39 && vmaSize != 42 && vmaSize != 48) {
     Printf("FATAL: ThreadSanitizer: unsupported VMA range\n");
     Printf("FATAL: Found %zd - Supported 39, 42 and 48\n", vmaSize);
     Die();
   }
+#else
+  if (vmaSize != 48) {
+    Printf("FATAL: ThreadSanitizer: unsupported VMA range\n");
+    Printf("FATAL: Found %zd - Supported 48\n", vmaSize);
+    Die();
+  }
+#endif
 #elif defined(__powerpc64__)
 # if !SANITIZER_GO
   if (vmaSize != 44 && vmaSize != 46 && vmaSize != 47) {