diff --git a/compiler-rt/lib/asan/asan_allocator.cpp b/compiler-rt/lib/asan/asan_allocator.cpp
index c28e71c13885..98698476329a 100644
--- a/compiler-rt/lib/asan/asan_allocator.cpp
+++ b/compiler-rt/lib/asan/asan_allocator.cpp
@@ -248,6 +248,15 @@ void AsanMapUnmapCallback::OnMap(uptr p, uptr size) const {
   thread_stats.mmaps++;
   thread_stats.mmaped += size;
 }
+
+void AsanMapUnmapCallback::OnMapSecondary(uptr p, uptr size) const {
+  PoisonShadow(p, size, kAsanHeapLeftRedzoneMagic);
+  // Statistics.
+  AsanStats &thread_stats = GetCurrentThreadStats();
+  thread_stats.mmaps++;
+  thread_stats.mmaped += size;
+}
+
 void AsanMapUnmapCallback::OnUnmap(uptr p, uptr size) const {
   PoisonShadow(p, size, 0);
   // We are about to unmap a chunk of user memory.
diff --git a/compiler-rt/lib/asan/asan_allocator.h b/compiler-rt/lib/asan/asan_allocator.h
index 6a12a6c60252..f6c3547506a8 100644
--- a/compiler-rt/lib/asan/asan_allocator.h
+++ b/compiler-rt/lib/asan/asan_allocator.h
@@ -114,6 +114,7 @@ class AsanChunkFifoList: public IntrusiveList<AsanChunk> {
 
 struct AsanMapUnmapCallback {
   void OnMap(uptr p, uptr size) const;
+  void OnMapSecondary(uptr p, uptr size) const;
   void OnUnmap(uptr p, uptr size) const;
 };
 
diff --git a/compiler-rt/lib/dfsan/dfsan_allocator.cpp b/compiler-rt/lib/dfsan/dfsan_allocator.cpp
index a3bed535dc08..6306e152392e 100644
--- a/compiler-rt/lib/dfsan/dfsan_allocator.cpp
+++ b/compiler-rt/lib/dfsan/dfsan_allocator.cpp
@@ -30,6 +30,7 @@ struct Metadata {
 
 struct DFsanMapUnmapCallback {
   void OnMap(uptr p, uptr size) const { dfsan_set_label(0, (void *)p, size); }
+  void OnMapSecondary(uptr p, uptr size) const { OnMap(p, size); }
   void OnUnmap(uptr p, uptr size) const { dfsan_set_label(0, (void *)p, size); }
 };
 
diff --git a/compiler-rt/lib/hwasan/hwasan_allocator.h b/compiler-rt/lib/hwasan/hwasan_allocator.h
index efe253de1258..093736d0e921 100644
--- a/compiler-rt/lib/hwasan/hwasan_allocator.h
+++ b/compiler-rt/lib/hwasan/hwasan_allocator.h
@@ -54,6 +54,7 @@ static_assert(sizeof(Metadata) == 16);
 
 struct HwasanMapUnmapCallback {
   void OnMap(uptr p, uptr size) const { UpdateMemoryUsage(); }
+  void OnMapSecondary(uptr p, uptr size) const { UpdateMemoryUsage(); }
   void OnUnmap(uptr p, uptr size) const {
     // We are about to unmap a chunk of user memory.
     // It can return as user-requested mmap() or another thread stack.
diff --git a/compiler-rt/lib/memprof/memprof_allocator.h b/compiler-rt/lib/memprof/memprof_allocator.h
index 001502cde08a..e11dc6174fea 100644
--- a/compiler-rt/lib/memprof/memprof_allocator.h
+++ b/compiler-rt/lib/memprof/memprof_allocator.h
@@ -39,6 +39,7 @@ void InitializeAllocator();
 
 struct MemprofMapUnmapCallback {
   void OnMap(uptr p, uptr size) const;
+  void OnMapSecondary(uptr p, uptr size) const { OnMap(p, size); }
   void OnUnmap(uptr p, uptr size) const;
 };
 
diff --git a/compiler-rt/lib/msan/msan_allocator.cpp b/compiler-rt/lib/msan/msan_allocator.cpp
index be0714dbf47e..1556e20f5332 100644
--- a/compiler-rt/lib/msan/msan_allocator.cpp
+++ b/compiler-rt/lib/msan/msan_allocator.cpp
@@ -30,6 +30,7 @@ struct Metadata {
 
 struct MsanMapUnmapCallback {
   void OnMap(uptr p, uptr size) const {}
+  void OnMapSecondary(uptr p, uptr size) const {}
   void OnUnmap(uptr p, uptr size) const {
     __msan_unpoison((void *)p, size);
 
diff --git a/compiler-rt/lib/sanitizer_common/sanitizer_allocator.h b/compiler-rt/lib/sanitizer_common/sanitizer_allocator.h
index 166a0539e4ba..72a7c83c4dab 100644
--- a/compiler-rt/lib/sanitizer_common/sanitizer_allocator.h
+++ b/compiler-rt/lib/sanitizer_common/sanitizer_allocator.h
@@ -64,6 +64,7 @@ inline void RandomShuffle(T *a, u32 n, u32 *rand_state) {
 
 struct NoOpMapUnmapCallback {
   void OnMap(uptr p, uptr size) const {}
+  void OnMapSecondary(uptr p, uptr size) const {}
   void OnUnmap(uptr p, uptr size) const {}
 };
 
diff --git a/compiler-rt/lib/sanitizer_common/sanitizer_allocator_secondary.h b/compiler-rt/lib/sanitizer_common/sanitizer_allocator_secondary.h
index 157645555604..648b1ab21f6b 100644
--- a/compiler-rt/lib/sanitizer_common/sanitizer_allocator_secondary.h
+++ b/compiler-rt/lib/sanitizer_common/sanitizer_allocator_secondary.h
@@ -99,7 +99,7 @@ class LargeMmapAllocator {
     if (!map_beg)
       return nullptr;
     CHECK(IsAligned(map_beg, page_size_));
-    MapUnmapCallback().OnMap(map_beg, map_size);
+    MapUnmapCallback().OnMapSecondary(map_beg, map_size);
     uptr map_end = map_beg + map_size;
     uptr res = map_beg + page_size_;
     if (res & (alignment - 1))  // Align.
diff --git a/compiler-rt/lib/sanitizer_common/tests/sanitizer_allocator_test.cpp b/compiler-rt/lib/sanitizer_common/tests/sanitizer_allocator_test.cpp
index 5a47fc11e6d0..28969d014c6a 100644
--- a/compiler-rt/lib/sanitizer_common/tests/sanitizer_allocator_test.cpp
+++ b/compiler-rt/lib/sanitizer_common/tests/sanitizer_allocator_test.cpp
@@ -476,11 +476,15 @@ TEST(SanitizerCommon, SizeClassAllocator32CompactGetBlockBegin) {
 #endif  // SANITIZER_CAN_USE_ALLOCATOR64
 
 struct TestMapUnmapCallback {
-  static int map_count, unmap_count;
+  static int map_count, map_secondary_count, unmap_count;
   void OnMap(uptr p, uptr size) const { map_count++; }
+  void OnMapSecondary(uptr p, uptr size) const { map_secondary_count++; }
   void OnUnmap(uptr p, uptr size) const { unmap_count++; }
+
+  static void Reset() { map_count = map_secondary_count = unmap_count = 0; }
 };
 int TestMapUnmapCallback::map_count;
+int TestMapUnmapCallback::map_secondary_count;
 int TestMapUnmapCallback::unmap_count;
 
 #if SANITIZER_CAN_USE_ALLOCATOR64
@@ -500,12 +504,12 @@ struct AP64WithCallback {
 };
 
 TEST(SanitizerCommon, SizeClassAllocator64MapUnmapCallback) {
-  TestMapUnmapCallback::map_count = 0;
-  TestMapUnmapCallback::unmap_count = 0;
+  TestMapUnmapCallback::Reset();
   typedef SizeClassAllocator64<AP64WithCallback<>> Allocator64WithCallBack;
   Allocator64WithCallBack *a = new Allocator64WithCallBack;
   a->Init(kReleaseToOSIntervalNever);
   EXPECT_EQ(TestMapUnmapCallback::map_count, 1);  // Allocator state.
+  EXPECT_EQ(TestMapUnmapCallback::map_secondary_count, 0);
   typename Allocator64WithCallBack::AllocatorCache cache;
   memset(&cache, 0, sizeof(cache));
   cache.Init(0);
@@ -516,6 +520,7 @@ TEST(SanitizerCommon, SizeClassAllocator64MapUnmapCallback) {
   a->GetFromAllocator(&stats, 30, chunks, kNumChunks);
   // State + alloc + metadata + freearray.
   EXPECT_EQ(TestMapUnmapCallback::map_count, 4);
+  EXPECT_EQ(TestMapUnmapCallback::map_secondary_count, 0);
   a->TestOnlyUnmap();
   EXPECT_EQ(TestMapUnmapCallback::unmap_count, 1);  // The whole thing.
   delete a;
@@ -536,12 +541,12 @@ struct AP32WithCallback {
 };
 
 TEST(SanitizerCommon, SizeClassAllocator32MapUnmapCallback) {
-  TestMapUnmapCallback::map_count = 0;
-  TestMapUnmapCallback::unmap_count = 0;
+  TestMapUnmapCallback::Reset();
   typedef SizeClassAllocator32<AP32WithCallback<>> Allocator32WithCallBack;
   Allocator32WithCallBack *a = new Allocator32WithCallBack;
   a->Init(kReleaseToOSIntervalNever);
   EXPECT_EQ(TestMapUnmapCallback::map_count, 0);
+  EXPECT_EQ(TestMapUnmapCallback::map_secondary_count, 0);
   Allocator32WithCallBack::AllocatorCache cache;
   memset(&cache, 0, sizeof(cache));
   cache.Init(0);
@@ -549,23 +554,21 @@ TEST(SanitizerCommon, SizeClassAllocator32MapUnmapCallback) {
   stats.Init();
   a->AllocateBatch(&stats, &cache, 32);
   EXPECT_EQ(TestMapUnmapCallback::map_count, 1);
+  EXPECT_EQ(TestMapUnmapCallback::map_secondary_count, 0);
   a->TestOnlyUnmap();
   EXPECT_EQ(TestMapUnmapCallback::unmap_count, 1);
   delete a;
-  // fprintf(stderr, "Map: %d Unmap: %d\n",
-  //         TestMapUnmapCallback::map_count,
-  //         TestMapUnmapCallback::unmap_count);
 }
 
 TEST(SanitizerCommon, LargeMmapAllocatorMapUnmapCallback) {
-  TestMapUnmapCallback::map_count = 0;
-  TestMapUnmapCallback::unmap_count = 0;
+  TestMapUnmapCallback::Reset();
   LargeMmapAllocator<TestMapUnmapCallback> a;
   a.Init();
   AllocatorStats stats;
   stats.Init();
   void *x = a.Allocate(&stats, 1 << 20, 1);
-  EXPECT_EQ(TestMapUnmapCallback::map_count, 1);
+  EXPECT_EQ(TestMapUnmapCallback::map_count, 0);
+  EXPECT_EQ(TestMapUnmapCallback::map_secondary_count, 1);
   a.Deallocate(&stats, x);
   EXPECT_EQ(TestMapUnmapCallback::unmap_count, 1);
 }
diff --git a/compiler-rt/lib/tsan/rtl/tsan_mman.cpp b/compiler-rt/lib/tsan/rtl/tsan_mman.cpp
index 7b9dc81a3f6c..f2cdb4fe04e7 100644
--- a/compiler-rt/lib/tsan/rtl/tsan_mman.cpp
+++ b/compiler-rt/lib/tsan/rtl/tsan_mman.cpp
@@ -25,6 +25,7 @@ namespace __tsan {
 
 struct MapUnmapCallback {
   void OnMap(uptr p, uptr size) const { }
+  void OnMapSecondary(uptr p, uptr size) const {};
   void OnUnmap(uptr p, uptr size) const {
     // We are about to unmap a chunk of user memory.
     // Mark the corresponding shadow memory as not needed.