diff --git a/compiler-rt/lib/tsan/rtl/tsan_mman.cpp b/compiler-rt/lib/tsan/rtl/tsan_mman.cpp
--- a/compiler-rt/lib/tsan/rtl/tsan_mman.cpp
+++ b/compiler-rt/lib/tsan/rtl/tsan_mman.cpp
@@ -57,7 +57,7 @@
     if (diff != 0)
       size -= diff;
     uptr p_meta = (uptr)MemToMeta(p);
-    ReleaseMemoryPagesToOS(p_meta, p_meta + size / kMetaRatio);
+    ReleaseTSANPages(p_meta, size / kMetaRatio);
   }
 };
 
diff --git a/compiler-rt/lib/tsan/rtl/tsan_platform.h b/compiler-rt/lib/tsan/rtl/tsan_platform.h
--- a/compiler-rt/lib/tsan/rtl/tsan_platform.h
+++ b/compiler-rt/lib/tsan/rtl/tsan_platform.h
@@ -1023,6 +1023,9 @@
 void DestroyThreadState();
 void PlatformCleanUpThreadState(ThreadState *thr);
 
+void ZeroPages(uptr addr, uptr size);
+void ReleaseTSANPages(uptr addr, uptr size);
+
 }  // namespace __tsan
 
 #endif  // TSAN_PLATFORM_H
diff --git a/compiler-rt/lib/tsan/rtl/tsan_platform_linux.cpp b/compiler-rt/lib/tsan/rtl/tsan_platform_linux.cpp
--- a/compiler-rt/lib/tsan/rtl/tsan_platform_linux.cpp
+++ b/compiler-rt/lib/tsan/rtl/tsan_platform_linux.cpp
@@ -147,7 +147,7 @@
 void FlushShadowMemoryCallback(
     const SuspendedThreadsList &suspended_threads_list,
     void *argument) {
-  ReleaseMemoryPagesToOS(ShadowBeg(), ShadowEnd());
+  ReleaseTSANPages(ShadowBeg(), ShadowEnd() - ShadowBeg());
 }
 #endif
 
diff --git a/compiler-rt/lib/tsan/rtl/tsan_platform_posix.cpp b/compiler-rt/lib/tsan/rtl/tsan_platform_posix.cpp
--- a/compiler-rt/lib/tsan/rtl/tsan_platform_posix.cpp
+++ b/compiler-rt/lib/tsan/rtl/tsan_platform_posix.cpp
@@ -121,6 +121,16 @@
 }
 #endif
 
+void ZeroPages(uptr addr, uptr size) {
+  UnmapOrDie((void*)addr, size);
+  if (!MmapFixedSuperNoReserve(addr, size))
+    Die();
+}
+
+void ReleaseTSANPages(uptr addr, uptr size) {
+  ReleaseMemoryPagesToOS(addr, addr + size);
+}
+
 }  // namespace __tsan
 
 #endif  // SANITIZER_POSIX
diff --git a/compiler-rt/lib/tsan/rtl/tsan_platform_windows.cpp b/compiler-rt/lib/tsan/rtl/tsan_platform_windows.cpp
--- a/compiler-rt/lib/tsan/rtl/tsan_platform_windows.cpp
+++ b/compiler-rt/lib/tsan/rtl/tsan_platform_windows.cpp
@@ -32,6 +32,15 @@
 void InitializePlatform() {
 }
 
+void ZeroPages(uptr addr, uptr size) {
+  // Unimplemented.
+  __builtin_trap();
+}
+
+void ReleaseTSANPages(uptr addr, uptr size) {
+  ReleaseMemoryPagesToOS(addr, addr + size);
+}
+
 }  // namespace __tsan
 
 #endif  // SANITIZER_WINDOWS
diff --git a/compiler-rt/lib/tsan/rtl/tsan_rtl.cpp b/compiler-rt/lib/tsan/rtl/tsan_rtl.cpp
--- a/compiler-rt/lib/tsan/rtl/tsan_rtl.cpp
+++ b/compiler-rt/lib/tsan/rtl/tsan_rtl.cpp
@@ -237,7 +237,8 @@
 #endif
 
 void DontNeedShadowFor(uptr addr, uptr size) {
-  ReleaseMemoryPagesToOS(MemToShadow(addr), MemToShadow(addr + size));
+  ReleaseTSANPages(MemToShadow(addr),
+                   MemToShadow(addr + size) - MemToShadow(addr));
 }
 
 #if !SANITIZER_GO
@@ -957,11 +958,11 @@
         *p++ = 0;
     }
     // Reset middle part.
-    u64 *p1 = p;
+    uptr p1 = reinterpret_cast<uptr>(p);
     p = RoundDown(end, kPageSize);
-    UnmapOrDie((void*)p1, (uptr)p - (uptr)p1);
-    if (!MmapFixedSuperNoReserve((uptr)p1, (uptr)p - (uptr)p1))
-      Die();
+
+    ZeroPages(p1, reinterpret_cast<uptr>(p) - p1);
+
     // Set the ending.
     while (p < end) {
       *p++ = val;
diff --git a/compiler-rt/lib/tsan/rtl/tsan_rtl_thread.cpp b/compiler-rt/lib/tsan/rtl/tsan_rtl_thread.cpp
--- a/compiler-rt/lib/tsan/rtl/tsan_rtl_thread.cpp
+++ b/compiler-rt/lib/tsan/rtl/tsan_rtl_thread.cpp
@@ -68,8 +68,7 @@
 void ThreadContext::OnReset() {
   CHECK_EQ(sync.size(), 0);
   uptr trace_p = GetThreadTrace(tid);
-  ReleaseMemoryPagesToOS(trace_p, trace_p + TraceSize() * sizeof(Event));
-  //!!! ReleaseMemoryToOS(GetThreadTraceHeader(tid), sizeof(Trace));
+  ReleaseTSANPages(trace_p, TraceSize() * sizeof(Event));
 }
 
 void ThreadContext::OnDetached(void *arg) {
diff --git a/compiler-rt/lib/tsan/rtl/tsan_sync.cpp b/compiler-rt/lib/tsan/rtl/tsan_sync.cpp
--- a/compiler-rt/lib/tsan/rtl/tsan_sync.cpp
+++ b/compiler-rt/lib/tsan/rtl/tsan_sync.cpp
@@ -174,9 +174,7 @@
   // meta objects in java heap).
   uptr metap = (uptr)MemToMeta(p0);
   uptr metasz = sz0 / kMetaRatio;
-  UnmapOrDie((void*)metap, metasz);
-  if (!MmapFixedSuperNoReserve(metap, metasz))
-    Die();
+  ZeroPages(metap, metasz);
 }
 
 MBlock* MetaMap::GetBlock(uptr p) {