From 4be3dcf0fc7a9086d978eaea3c5a4d78fb98e44a Mon Sep 17 00:00:00 2001
From: Lucas Wilkinson <LucasWilkinson@users.noreply.github.com>
Date: Mon, 14 Sep 2026 10:20:46 -0400
Subject: [PATCH] [PCP][DCP] Declare FlashMLASparse MTP support at CP
 interleave > 1 (#56722)

Co-authored-by: Claude Opus 5 (1M context) <noreply@anthropic.com>
---
 vllm/v1/attention/backends/mla/flashmla_sparse.py | 1 +
 1 file changed, 1 insertion(+)

diff --git a/vllm/v1/attention/backends/mla/flashmla_sparse.py b/vllm/v1/attention/backends/mla/flashmla_sparse.py
index 433cded567..d8c4368401 100644
--- a/vllm/v1/attention/backends/mla/flashmla_sparse.py
+++ b/vllm/v1/attention/backends/mla/flashmla_sparse.py
@@ -634,6 +634,7 @@ class FlashMLASparseMetadataBuilder(
 class FlashMLASparseImpl(SparseMLACommonImpl[FlashMLASparseMetadata]):
     can_return_lse_for_decode: bool = True
     supports_dcp: bool = True
+    supports_mtp_with_cp_non_trivial_interleave_size: bool = True
 
     @staticmethod
     def _compute_fp8_decode_padded_heads(num_heads: int) -> int: