From 6eedc0acb09f5ddbf9adfc8fc33f5682a99557c9 Mon Sep 17 00:00:00 2001
From: RoyWang <Roy.Wang@amd.com>
Date: Tue, 30 Dec 2025 04:19:40 +0800
Subject: [PATCH] [fix]: fix sliding_tile_attn with sdpa(without flash_attn)
 (#967)

Co-authored-by: roywang <roywang@amd.com>
Co-authored-by: Will Lin <wlsaidhi@gmail.com>
---
 fastvideo/attention/backends/sdpa.py | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/fastvideo/attention/backends/sdpa.py b/fastvideo/attention/backends/sdpa.py
index 9c2ea4b8a..cbb9dbb00 100644
--- a/fastvideo/attention/backends/sdpa.py
+++ b/fastvideo/attention/backends/sdpa.py
@@ -82,7 +82,9 @@ class SDPAImpl(AttentionImpl):
         key = key.transpose(1, 2)
         value = value.transpose(1, 2)
 
-        attn_mask = attn_metadata.attn_mask if attn_metadata is not None else None
+        attn_mask = attn_metadata.attn_mask if (
+            attn_metadata is not None
+            and hasattr(attn_metadata, "attn_mask")) else None
         attn_kwargs = {
             "attn_mask": attn_mask,
             "dropout_p": self.dropout,