diff --git a/test/test_tpu_paged_attention_kernel.py b/test/test_tpu_paged_attention_kernel.py
index 80023652d69..d2d0f4f19a9 100644
--- a/test/test_tpu_paged_attention_kernel.py
+++ b/test/test_tpu_paged_attention_kernel.py
@@ -162,7 +162,8 @@ def test_paged_attention_without_query_padding(
         num_kv_pages_per_compute_block=num_kv_pages_per_compute_block,
         num_queries_per_compute_block=num_queries_per_compute_block,
     )
-    # actual_output = jax.block_until_ready(actual_output)
+    # Note kernel execution is async. Without blocking, if an error happens in the kernel, the error may point to some irrelevant  and confusing places. See https://github.com/pytorch/xla/pull/8356#issuecomment-2486861631
+    actual_output = jax.block_until_ready(actual_output)
 
     # Run the ref impl.
     expected_output = _ref_jax_extended_paged_attention(
@@ -219,7 +220,7 @@ def test_paged_attention_with_query_padding(
       block_kv_size,
   ):
 
-    max_kv_len = 2048
+    max_kv_len = 512
     # Set query_len>kv_seq_lens
     query_len = max_kv_len
     batch_size = 3
@@ -259,7 +260,7 @@ def test_paged_attention_with_query_padding(
         num_kv_pages_per_compute_block=num_kv_pages_per_compute_block,
         num_queries_per_compute_block=num_queries_per_compute_block,
     )
-    # actual_output = jax.block_until_ready(actual_output)
+    actual_output = jax.block_until_ready(actual_output)
 
     # Run the ref impl.
     expected_output = _ref_jax_extended_paged_attention(