diff --git a/llvm/include/llvm/ExecutionEngine/Orc/MemoryMapper.h b/llvm/include/llvm/ExecutionEngine/Orc/MemoryMapper.h
index 0b4cda119cadd..80dac5aee80bc 100644
--- a/llvm/include/llvm/ExecutionEngine/Orc/MemoryMapper.h
+++ b/llvm/include/llvm/ExecutionEngine/Orc/MemoryMapper.h
@@ -102,6 +102,7 @@ class InProcessMemoryMapper final : public MemoryMapper {
 
 private:
   struct Allocation {
+    size_t Size;
     std::vector<shared::WrapperFunctionCall> DeinitializationActions;
   };
   using AllocationMap = DenseMap<ExecutorAddr, Allocation>;
diff --git a/llvm/lib/ExecutionEngine/Orc/MapperJITLinkMemoryManager.cpp b/llvm/lib/ExecutionEngine/Orc/MapperJITLinkMemoryManager.cpp
index b9328f0a16edf..bd773a10d9174 100644
--- a/llvm/lib/ExecutionEngine/Orc/MapperJITLinkMemoryManager.cpp
+++ b/llvm/lib/ExecutionEngine/Orc/MapperJITLinkMemoryManager.cpp
@@ -147,17 +147,35 @@ void MapperJITLinkMemoryManager::allocate(const JITLinkDylib *JD, LinkGraph &G,
 
 void MapperJITLinkMemoryManager::deallocate(
     std::vector<FinalizedAlloc> Allocs, OnDeallocatedFunction OnDeallocated) {
-  std::lock_guard<std::mutex> Lock(Mutex);
-
+  std::vector<ExecutorAddr> Bases;
+  Bases.reserve(Allocs.size());
   for (auto &FA : Allocs) {
     ExecutorAddr Addr = FA.getAddress();
-    ExecutorAddrDiff Size = UsedMemory[Addr];
-    UsedMemory.erase(Addr);
-
-    AvailableMemory.push_back({Addr, Addr + Size});
-    FA.release();
+    Bases.push_back(Addr);
   }
-  OnDeallocated(Error::success());
+
+  Mapper->deinitialize(Bases, [this, Allocs = std::move(Allocs),
+                               OnDeallocated = std::move(OnDeallocated)](
+                                  llvm::Error Err) mutable {
+    if (Err)
+      OnDeallocated(std::move(Err));
+
+    {
+      std::lock_guard<std::mutex> Lock(Mutex);
+
+      for (auto &FA : Allocs) {
+        ExecutorAddr Addr = FA.getAddress();
+        ExecutorAddrDiff Size = UsedMemory[Addr];
+
+        UsedMemory.erase(Addr);
+        AvailableMemory.push_back({Addr, Addr + Size});
+
+        FA.release();
+      }
+    }
+
+    OnDeallocated(Error::success());
+  });
 }
 
 } // end namespace orc
diff --git a/llvm/lib/ExecutionEngine/Orc/MemoryMapper.cpp b/llvm/lib/ExecutionEngine/Orc/MemoryMapper.cpp
index ee92e5191b507..1e8ad27342d72 100644
--- a/llvm/lib/ExecutionEngine/Orc/MemoryMapper.cpp
+++ b/llvm/lib/ExecutionEngine/Orc/MemoryMapper.cpp
@@ -60,6 +60,7 @@ char *InProcessMemoryMapper::prepare(ExecutorAddr Addr, size_t ContentSize) {
 void InProcessMemoryMapper::initialize(MemoryMapper::AllocInfo &AI,
                                        OnInitializedFunction OnInitialized) {
   ExecutorAddr MinAddr(~0ULL);
+  ExecutorAddr MaxAddr(0);
 
   for (auto &Segment : AI.Segments) {
     auto Base = AI.MappingBase + Segment.Offset;
@@ -68,6 +69,9 @@ void InProcessMemoryMapper::initialize(MemoryMapper::AllocInfo &AI,
     if (Base < MinAddr)
       MinAddr = Base;
 
+    if (Base + Size > MaxAddr)
+      MaxAddr = Base + Size;
+
     std::memset((Base + Segment.ContentSize).toPtr<void *>(), 0,
                 Segment.ZeroFillSize);
 
@@ -85,6 +89,9 @@ void InProcessMemoryMapper::initialize(MemoryMapper::AllocInfo &AI,
 
   {
     std::lock_guard<std::mutex> Lock(Mutex);
+
+    // This is the maximum range whose permission have been possibly modified
+    Allocations[MinAddr].Size = MaxAddr - MinAddr;
     Allocations[MinAddr].DeinitializationActions =
         std::move(*DeinitializeActions);
     Reservations[AI.MappingBase.toPtr<void *>()].Allocations.push_back(MinAddr);
@@ -108,6 +115,14 @@ void InProcessMemoryMapper::deinitialize(
         AllErr = joinErrors(std::move(AllErr), std::move(Err));
       }
 
+      // Reset protections to read/write so the area can be reused
+      if (auto EC = sys::Memory::protectMappedMemory(
+              {Base.toPtr<void *>(), Allocations[Base].Size},
+              sys::Memory::ProtectionFlags::MF_READ |
+                  sys::Memory::ProtectionFlags::MF_WRITE)) {
+        AllErr = joinErrors(std::move(AllErr), errorCodeToError(EC));
+      }
+
       Allocations.erase(Base);
     }
   }
diff --git a/llvm/unittests/ExecutionEngine/Orc/MapperJITLinkMemoryManagerTest.cpp b/llvm/unittests/ExecutionEngine/Orc/MapperJITLinkMemoryManagerTest.cpp
index 74d8387701359..ca1b13c759f63 100644
--- a/llvm/unittests/ExecutionEngine/Orc/MapperJITLinkMemoryManagerTest.cpp
+++ b/llvm/unittests/ExecutionEngine/Orc/MapperJITLinkMemoryManagerTest.cpp
@@ -118,11 +118,17 @@ TEST(MapperJITLinkMemoryManagerTest, InProcess) {
   StringRef TargetHello2(TargetMem2, Hello.size());
   EXPECT_EQ(Hello, TargetHello2);
 
+  EXPECT_EQ(Counter->DeinitCount, 0);
+
   auto Err2 = MemMgr->deallocate(std::move(*FA1));
   EXPECT_THAT_ERROR(std::move(Err2), Succeeded());
 
+  EXPECT_EQ(Counter->DeinitCount, 1);
+
   auto Err3 = MemMgr->deallocate(std::move(*FA2));
   EXPECT_THAT_ERROR(std::move(Err3), Succeeded());
+
+  EXPECT_EQ(Counter->DeinitCount, 2);
 }
 
 } // namespace