diff --git a/drivers/gpu/drm/drm_syncobj.c b/drivers/gpu/drm/drm_syncobj.c
index 57bf6006394d..827d2ea5bb79 100644
--- a/drivers/gpu/drm/drm_syncobj.c
+++ b/drivers/gpu/drm/drm_syncobj.c
@@ -125,23 +125,24 @@ static int drm_syncobj_fence_get_or_add_callback(struct drm_syncobj *syncobj,
 	if (!ret)
 		return 1;
 
-	spin_lock(&syncobj->lock);
+	spin_lock(&syncobj->pt_lock);
 	/* We've already tried once to get a fence and failed.  Now that we
 	 * have the lock, try one more time just to be sure we don't add a
 	 * callback when a fence has already been set.
 	 */
 	if (!list_empty(&syncobj->signal_pt_list)) {
-		spin_unlock(&syncobj->lock);
+		spin_unlock(&syncobj->pt_lock);
 		drm_syncobj_search_fence(syncobj, 0, 0, fence);
 		if (*fence)
 			return 1;
-		spin_lock(&syncobj->lock);
 	} else {
+		spin_unlock(&syncobj->pt_lock);
 		*fence = NULL;
+		mutex_lock(&syncobj->cb_mutex);
 		drm_syncobj_add_callback_locked(syncobj, cb, func);
+		mutex_unlock(&syncobj->cb_mutex);
 		ret = 0;
 	}
-	spin_unlock(&syncobj->lock);
 
 	return ret;
 }
@@ -150,43 +151,43 @@ void drm_syncobj_add_callback(struct drm_syncobj *syncobj,
 			      struct drm_syncobj_cb *cb,
 			      drm_syncobj_func_t func)
 {
-	spin_lock(&syncobj->lock);
+	mutex_lock(&syncobj->cb_mutex);
 	drm_syncobj_add_callback_locked(syncobj, cb, func);
-	spin_unlock(&syncobj->lock);
+	mutex_unlock(&syncobj->cb_mutex);
 }
 
 void drm_syncobj_remove_callback(struct drm_syncobj *syncobj,
 				 struct drm_syncobj_cb *cb)
 {
-	spin_lock(&syncobj->lock);
+	mutex_lock(&syncobj->cb_mutex);
 	list_del_init(&cb->node);
-	spin_unlock(&syncobj->lock);
+	mutex_unlock(&syncobj->cb_mutex);
 }
 
 static void drm_syncobj_init(struct drm_syncobj *syncobj)
 {
-	spin_lock(&syncobj->lock);
+	spin_lock(&syncobj->pt_lock);
 	syncobj->timeline_context = dma_fence_context_alloc(1);
 	syncobj->timeline = 0;
 	syncobj->signal_point = 0;
 	init_waitqueue_head(&syncobj->wq);
 
 	INIT_LIST_HEAD(&syncobj->signal_pt_list);
-	spin_unlock(&syncobj->lock);
+	spin_unlock(&syncobj->pt_lock);
 }
 
 static void drm_syncobj_fini(struct drm_syncobj *syncobj)
 {
 	struct drm_syncobj_signal_pt *signal_pt = NULL, *tmp;
 
-	spin_lock(&syncobj->lock);
+	spin_lock(&syncobj->pt_lock);
 	list_for_each_entry_safe(signal_pt, tmp,
 				 &syncobj->signal_pt_list, list) {
 		list_del(&signal_pt->list);
 		dma_fence_put(&signal_pt->fence_array->base);
 		kfree(signal_pt);
 	}
-	spin_unlock(&syncobj->lock);
+	spin_unlock(&syncobj->pt_lock);
 }
 
 static struct dma_fence
@@ -249,14 +250,14 @@ static int drm_syncobj_create_signal_pt(struct drm_syncobj *syncobj,
 	fences[num_fences++] = dma_fence_get(fence);
 	/* timeline syncobj must take this dependency */
 	if (syncobj->type == DRM_SYNCOBJ_TYPE_TIMELINE) {
-		spin_lock(&syncobj->lock);
+		spin_lock(&syncobj->pt_lock);
 		if (!list_empty(&syncobj->signal_pt_list)) {
 			tail_pt = list_last_entry(&syncobj->signal_pt_list,
 						  struct drm_syncobj_signal_pt, list);
 			fences[num_fences++] =
 				dma_fence_get(&tail_pt->fence_array->base);
 		}
-		spin_unlock(&syncobj->lock);
+		spin_unlock(&syncobj->pt_lock);
 	}
 	signal_pt->fence_array = dma_fence_array_create(num_fences, fences,
 							syncobj->timeline_context,
@@ -266,16 +267,16 @@ static int drm_syncobj_create_signal_pt(struct drm_syncobj *syncobj,
 		goto fail;
 	}
 
-	spin_lock(&syncobj->lock);
+	spin_lock(&syncobj->pt_lock);
 	if (syncobj->signal_point >= point) {
 		DRM_WARN("A later signal is ready!");
-		spin_unlock(&syncobj->lock);
+		spin_unlock(&syncobj->pt_lock);
 		goto exist;
 	}
 	signal_pt->value = point;
 	list_add_tail(&signal_pt->list, &syncobj->signal_pt_list);
 	syncobj->signal_point = point;
-	spin_unlock(&syncobj->lock);
+	spin_unlock(&syncobj->pt_lock);
 	wake_up_all(&syncobj->wq);
 
 	return 0;
@@ -294,7 +295,7 @@ static void drm_syncobj_garbage_collection(struct drm_syncobj *syncobj)
 {
 	struct drm_syncobj_signal_pt *signal_pt, *tmp, *tail_pt;
 
-	spin_lock(&syncobj->lock);
+	spin_lock(&syncobj->pt_lock);
 	tail_pt = list_last_entry(&syncobj->signal_pt_list,
 				  struct drm_syncobj_signal_pt,
 				  list);
@@ -315,7 +316,7 @@ static void drm_syncobj_garbage_collection(struct drm_syncobj *syncobj)
 		}
 	}
 
-	spin_unlock(&syncobj->lock);
+	spin_unlock(&syncobj->pt_lock);
 }
 /**
  * drm_syncobj_replace_fence - replace fence in a sync object.
@@ -344,13 +345,14 @@ void drm_syncobj_replace_fence(struct drm_syncobj *syncobj,
 	drm_syncobj_create_signal_pt(syncobj, fence, pt_value);
 	if (fence) {
 		struct drm_syncobj_cb *cur, *tmp;
+		LIST_HEAD(cb_list);
 
-		spin_lock(&syncobj->lock);
+		mutex_lock(&syncobj->cb_mutex);
 		list_for_each_entry_safe(cur, tmp, &syncobj->cb_list, node) {
 			list_del_init(&cur->node);
 			cur->func(syncobj, cur);
 		}
-		spin_unlock(&syncobj->lock);
+		mutex_unlock(&syncobj->cb_mutex);
 	}
 }
 EXPORT_SYMBOL(drm_syncobj_replace_fence);
@@ -386,11 +388,11 @@ drm_syncobj_point_get(struct drm_syncobj *syncobj, u64 point, u64 flags,
 		if (ret < 0)
 			return ret;
 	}
-	spin_lock(&syncobj->lock);
+	spin_lock(&syncobj->pt_lock);
 	*fence = drm_syncobj_find_signal_pt_for_point(syncobj, point);
 	if (!*fence)
 		ret = -EINVAL;
-	spin_unlock(&syncobj->lock);
+	spin_unlock(&syncobj->pt_lock);
 	return ret;
 }
 
@@ -500,7 +502,8 @@ int drm_syncobj_create(struct drm_syncobj **out_syncobj, uint32_t flags,
 
 	kref_init(&syncobj->refcount);
 	INIT_LIST_HEAD(&syncobj->cb_list);
-	spin_lock_init(&syncobj->lock);
+	spin_lock_init(&syncobj->pt_lock);
+	mutex_init(&syncobj->cb_mutex);
 	if (flags & DRM_SYNCOBJ_CREATE_TYPE_TIMELINE)
 		syncobj->type = DRM_SYNCOBJ_TYPE_TIMELINE;
 	else
diff --git a/include/drm/drm_syncobj.h b/include/drm/drm_syncobj.h
index 5e8c5c027e09..30197ad7a575 100644
--- a/include/drm/drm_syncobj.h
+++ b/include/drm/drm_syncobj.h
@@ -75,9 +75,13 @@ struct drm_syncobj {
          */
 	struct list_head cb_list;
 	/**
-	 * @lock: Protects syncobj list and write-locks &fence.
+	 * @pt_lock: Protects pt list.
 	 */
-	spinlock_t lock;
+	spinlock_t pt_lock;
+	/**
+	 * @cb_mutex: mutex between syncobj cb execution and free.
+	 */
+	struct mutex cb_mutex;
 	/**
 	 * @file: A file backing for this syncobj.
 	 */
