diff --git a/tests/unit/test_umma_qk_hd64.cu b/tests/unit/test_umma_qk_hd64.cu
index 5726216a..6a671f32 100644
--- a/tests/unit/test_umma_qk_hd64.cu
+++ b/tests/unit/test_umma_qk_hd64.cu
@@ -130,6 +130,14 @@ test_umma_qk_hd64(const bf16_t* q, const bf16_t* k,
 
         bool accumulate = (kt > 0);
 
+        // Debug: write descriptor info
+        if (tid == 0 && kt == 0) {
+            s_out[240] = (float)q_ktile_addr;
+            s_out[241] = (float)k_ktile_addr;
+            s_out[242] = (float)desc_q;
+            s_out[243] = (float)desc_k;
+        }
+
         // 4 warp leaders call MMA
         if (lane == 0) {
             umma_ss_f16(tb, desc_q, desc_k, idesc, accumulate);
@@ -186,9 +194,8 @@ int main() {
     float* h_s_out = (float*)calloc(128 * 16, sizeof(float));
     float* h_s_scalar = (float*)calloc(SK, sizeof(float));
 
-    srand(42);
-    for (int d = 0; d < HD; d++) h_q[d] = f32_to_bf16_host((float)(rand()%100)/100.0f - 0.5f);
-    for (int i = 0; i < SK*HD; i++) h_k[i] = f32_to_bf16_host((float)(rand()%100)/100.0f - 0.5f);
+    for (int d = 0; d < HD; d++) h_q[d] = f32_to_bf16_host(1.0f);
+    for (int i = 0; i < SK*HD; i++) h_k[i] = f32_to_bf16_host(1.0f);
 
     bf16_t *d_q, *d_k; float *d_s_out, *d_s_scalar;
     cudaMalloc(&d_q, HD*sizeof(bf16_t)); cudaMalloc(&d_k, SK*HD*sizeof(bf16_t));