[Fix] DSA: size cudagraph page_table to req_to_token width (#29379)

Co-authored-by: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
2026-06-26 12:17:34 -07:00
parent be1930133a
commit ee77a7d330
1 changed files with 3 additions and 3 deletions
@@ -1003,11 +1003,11 @@ class DeepseekSparseAttnBackend(
                max_bs + 1, dtype=torch.int32, device=self.device
            ),
            # fake page_table for sparse_prefill
-            # Add extra columns for speculative draft tokens to avoid
-            # overflow during target_verify when max_seqlen_k = seq_len + num_draft_tokens
+            # Match req_to_token's width exactly. It is over-allocated beyond
+            # context_len because spec decoding lets seq_len transiently overshoot.
            "page_table": torch.zeros(
                max_num_tokens,
-                self.max_context_len + (self.speculative_num_draft_tokens or 0),
+                self.req_to_token.shape[1],
                dtype=torch.int32,
                device=self.device,
            ),