fix maxpool grad

mindspore/ccsrc/backend/kernel_compiler/gpu/nn/pooling_grad_gpu_kernel.h

@@ -176,7 +176,7 @@ class PoolingGradGpuKernel : public GpuKernel {
   }
   void InitSizeLists() override {
     if (!is_null_input_) {
-      CHECK_CUDNN_RET_WITH_EXCEPT(kernel_node_, cudnnGetTensorSizeInBytes(y_descriptor_, &input_size_),
+      CHECK_CUDNN_RET_WITH_EXCEPT(kernel_node_, cudnnGetTensorSizeInBytes(x_descriptor_, &input_size_),
                                   "cudnnGetTensorSizeInBytes failed");
       CHECK_CUDNN_RET_WITH_EXCEPT(kernel_node_, cudnnGetTensorSizeInBytes(dx_descriptor_, &output_size_),
                                   "cudnnGetTensorSizeInBytes failed");
@@ -184,13 +184,13 @@ class PoolingGradGpuKernel : public GpuKernel {
     input_size_list_.push_back(input_size_);
     output_size_list_.push_back(output_size_);
     if (!is_null_input_) {
-      CHECK_CUDNN_RET_WITH_EXCEPT(kernel_node_, cudnnGetTensorSizeInBytes(dy_descriptor_, &input_size_),
+      CHECK_CUDNN_RET_WITH_EXCEPT(kernel_node_, cudnnGetTensorSizeInBytes(y_descriptor_, &input_size_),
                                   "cudnnGetTensorSizeInBytes failed");
     }
     input_size_list_.push_back(input_size_);
 
     if (!is_null_input_) {
-      CHECK_CUDNN_RET_WITH_EXCEPT(kernel_node_, cudnnGetTensorSizeInBytes(x_descriptor_, &input_size_),
+      CHECK_CUDNN_RET_WITH_EXCEPT(kernel_node_, cudnnGetTensorSizeInBytes(dy_descriptor_, &input_size_),
                                   "cudnnGetTensorSizeInBytes failed");
     }
     input_size_list_.push_back(input_size_);