diff --git a/mace/kernels/opencl/cl/conv_2d_3x3.cl b/mace/kernels/opencl/cl/conv_2d_3x3.cl
index 0dbafb2d1afb06e068a1e982e6c613bcbcf47bc0..c51cc2b6f03993538cd300b33688bb23fd447104 100644
--- a/mace/kernels/opencl/cl/conv_2d_3x3.cl
+++ b/mace/kernels/opencl/cl/conv_2d_3x3.cl
@@ -33,7 +33,7 @@ void kernel conv_2d_3x3(global const float *input,
   const float *input_base = input + in_offset + in_pixel_begin;
   float *output_base = output + out_offset + out_pixel_begin;
 
-  uint pixels = out_pixel_end - out_pixel_begin;
+  const int pixels = out_pixel_end - out_pixel_begin;
 
   for (int i = out_chan_begin; i < out_chan_end; ++i) {
     float *output_ptr = output_base + i * out_pixel;
diff --git a/mace/kernels/opencl/cl/depthwise_conv_3x3.cl b/mace/kernels/opencl/cl/depthwise_conv_3x3.cl
index 5290528927da2ba9b548c104c9903144f73e7f53..9f9a6fc44cdf6f1f6cdbf1ad07734541857fb91b 100644
--- a/mace/kernels/opencl/cl/depthwise_conv_3x3.cl
+++ b/mace/kernels/opencl/cl/depthwise_conv_3x3.cl
@@ -35,7 +35,7 @@ void kernel depthwise_conv_3x3(global const float *input, /* n, c, h, w */
   const float *input_base = input + in_offset + in_pixel_begin;
   float *output_base = output + out_offset + out_pixel_begin;
 
-  uint pixels = out_pixel_end - out_pixel_begin;
+  const int pixels = out_pixel_end - out_pixel_begin;
 
   for (int i = out_chan_begin; i < out_chan_end; ++i) {
     float bias_value = bias[i];
diff --git a/mace/ops/conv_2d_test.cc b/mace/ops/conv_2d_test.cc
index aff87a1adbf74de496d5edf1090355278cf7a58b..31d3130a88796bd21776e2a67ea12be1ed9a7fdb 100644
--- a/mace/ops/conv_2d_test.cc
+++ b/mace/ops/conv_2d_test.cc
@@ -296,7 +296,7 @@ static void TestUnalignedConvNxNS12() {
     ExpectTensorNear<float>(expected, *net.GetOutput("Output"), 0.001);
   };
 
-  for (int kernel_size : {3}) {
+  for (int kernel_size : {1, 3, 5}) {
     for (int stride : {1, 2}) {
       func(kernel_size, kernel_size, stride, stride, VALID);
       func(kernel_size, kernel_size, stride, stride, SAME);