diff --git a/libs/binder/IPCThreadState.cpp b/libs/binder/IPCThreadState.cpp
index a3a2f87..28ce935 100644
--- a/libs/binder/IPCThreadState.cpp
+++ b/libs/binder/IPCThreadState.cpp
@@ -895,21 +895,21 @@
                             tr.data_size,
                             reinterpret_cast<const binder_size_t*>(tr.data.ptr.offsets),
                             tr.offsets_size/sizeof(binder_size_t),
-                            freeBuffer, this);
+                            freeBuffer);
                     } else {
                         err = *reinterpret_cast<const status_t*>(tr.data.ptr.buffer);
                         freeBuffer(nullptr,
                             reinterpret_cast<const uint8_t*>(tr.data.ptr.buffer),
                             tr.data_size,
                             reinterpret_cast<const binder_size_t*>(tr.data.ptr.offsets),
-                            tr.offsets_size/sizeof(binder_size_t), this);
+                            tr.offsets_size/sizeof(binder_size_t));
                     }
                 } else {
                     freeBuffer(nullptr,
                         reinterpret_cast<const uint8_t*>(tr.data.ptr.buffer),
                         tr.data_size,
                         reinterpret_cast<const binder_size_t*>(tr.data.ptr.offsets),
-                        tr.offsets_size/sizeof(binder_size_t), this);
+                        tr.offsets_size/sizeof(binder_size_t));
                     continue;
                 }
             }
@@ -1183,7 +1183,7 @@
                 reinterpret_cast<const uint8_t*>(tr.data.ptr.buffer),
                 tr.data_size,
                 reinterpret_cast<const binder_size_t*>(tr.data.ptr.offsets),
-                tr.offsets_size/sizeof(binder_size_t), freeBuffer, this);
+                tr.offsets_size/sizeof(binder_size_t), freeBuffer);
 
             const void* origServingStackPointer = mServingStackPointer;
             mServingStackPointer = &origServingStackPointer; // anything on the stack
@@ -1370,7 +1370,7 @@
 void IPCThreadState::freeBuffer(Parcel* parcel, const uint8_t* data,
                                 size_t /*dataSize*/,
                                 const binder_size_t* /*objects*/,
-                                size_t /*objectsSize*/, void* /*cookie*/)
+                                size_t /*objectsSize*/)
 {
     //ALOGI("Freeing parcel %p", &parcel);
     IF_LOG_COMMANDS() {
diff --git a/libs/binder/Parcel.cpp b/libs/binder/Parcel.cpp
index feeb819..46883d1 100644
--- a/libs/binder/Parcel.cpp
+++ b/libs/binder/Parcel.cpp
@@ -2509,7 +2509,7 @@
 }
 
 void Parcel::ipcSetDataReference(const uint8_t* data, size_t dataSize,
-    const binder_size_t* objects, size_t objectsCount, release_func relFunc, void* relCookie)
+    const binder_size_t* objects, size_t objectsCount, release_func relFunc)
 {
     binder_size_t minOffset = 0;
     freeDataNoInit();
@@ -2524,7 +2524,6 @@
     mNextObjectHint = 0;
     mObjectsSorted = false;
     mOwner = relFunc;
-    mOwnerCookie = relCookie;
     for (size_t i = 0; i < mObjectsSize; i++) {
         binder_size_t offset = mObjects[i];
         if (offset < minOffset) {
@@ -2625,7 +2624,7 @@
     if (mOwner) {
         LOG_ALLOC("Parcel %p: freeing other owner data", this);
         //ALOGI("Freeing data ref of %p (pid=%d)", this, getpid());
-        mOwner(this, mData, mDataSize, mObjects, mObjectsSize, mOwnerCookie);
+        mOwner(this, mData, mDataSize, mObjects, mObjectsSize);
     } else {
         LOG_ALLOC("Parcel %p: freeing allocated data", this);
         releaseObjects();
@@ -2788,7 +2787,7 @@
             memcpy(objects, mObjects, objectsSize*sizeof(binder_size_t));
         }
         //ALOGI("Freeing data ref of %p (pid=%d)", this, getpid());
-        mOwner(this, mData, mDataSize, mObjects, mObjectsSize, mOwnerCookie);
+        mOwner(this, mData, mDataSize, mObjects, mObjectsSize);
         mOwner = nullptr;
 
         LOG_ALLOC("Parcel %p: taking ownership of %zu capacity", this, desired);
diff --git a/libs/binder/include/binder/IPCThreadState.h b/libs/binder/include/binder/IPCThreadState.h
index 49ef253..abd258e 100644
--- a/libs/binder/include/binder/IPCThreadState.h
+++ b/libs/binder/include/binder/IPCThreadState.h
@@ -186,9 +186,8 @@
     static  void                threadDestructor(void *st);
     static  void                freeBuffer(Parcel* parcel,
                                            const uint8_t* data, size_t dataSize,
-                                           const binder_size_t* objects, size_t objectsSize,
-                                           void* cookie);
-    
+                                           const binder_size_t* objects, size_t objectsSize);
+
     const   sp<ProcessState>    mProcess;
             Vector<BBinder*>    mPendingStrongDerefs;
             Vector<RefBase::weakref_type*> mPendingWeakDerefs;
diff --git a/libs/binder/include/binder/Parcel.h b/libs/binder/include/binder/Parcel.h
index 84bfe38..d16ef52 100644
--- a/libs/binder/include/binder/Parcel.h
+++ b/libs/binder/include/binder/Parcel.h
@@ -488,24 +488,21 @@
     // uid.
     uid_t               readCallingWorkSourceUid() const;
 
+    void                print(TextOutput& to, uint32_t flags = 0) const;
+
 private:
     typedef void        (*release_func)(Parcel* parcel,
                                         const uint8_t* data, size_t dataSize,
-                                        const binder_size_t* objects, size_t objectsSize,
-                                        void* cookie);
-                        
+                                        const binder_size_t* objects, size_t objectsSize);
+
     uintptr_t           ipcData() const;
     size_t              ipcDataSize() const;
     uintptr_t           ipcObjects() const;
     size_t              ipcObjectsCount() const;
     void                ipcSetDataReference(const uint8_t* data, size_t dataSize,
                                             const binder_size_t* objects, size_t objectsCount,
-                                            release_func relFunc, void* relCookie);
-    
-public:
-    void                print(TextOutput& to, uint32_t flags = 0) const;
+                                            release_func relFunc);
 
-private:
                         Parcel(const Parcel& o);
     Parcel&             operator=(const Parcel& o);
     
@@ -612,7 +609,9 @@
     mutable bool        mDeallocZero;
 
     release_func        mOwner;
-    void*               mOwnerCookie;
+
+    // TODO(167966510): reserved for binder/version/stability
+    void*               mReserved = reinterpret_cast<void*>(0xAAAAAAAA);
 
     class Blob {
     public: