CUDA: fix FA kernel selection logic (llama/21271)

diff --git a/src/ggml-cuda/fattn.cu b/src/ggml-cuda/fattn.cu
index a21c53610483cad03ee00a0678eb594d477becff..addf93205ef92d8bf18840142867a9ffbf59619b 100644 (file)
--- a/src/ggml-cuda/fattn.cu
+++ b/src/ggml-cuda/fattn.cu
@@ -340,7 +340,14 @@ static best_fattn_kernel ggml_cuda_get_best_fattn_kernel(const int device, const
         case 128:
         case 112:
         case 256:
+            if (V->ne[0] != K->ne[0]) {
+                return BEST_FATTN_KERNEL_NONE;
+            }
+            break;
         case 512:
+            if (V->ne[0] != K->ne[0]) {
+                return BEST_FATTN_KERNEL_NONE;
+            }
             if (!gqa_opt_applies) {
                 return BEST_FATTN_KERNEL_NONE;
             }