diff --git a/hopper/flash_api.cpp b/hopper/flash_api.cpp
index 7ab4352984e..43f3387d1df 100644
--- a/hopper/flash_api.cpp
+++ b/hopper/flash_api.cpp
@@ -1535,10 +1535,11 @@ std::tuple<at::Tensor, at::Tensor, at::Tensor, at::Tensor, at::Tensor> mha_bwd(
     // Will be zero'ed out in the backward preprocess kernel
     at::Tensor dq_semaphore = torch::empty({(seqlen_q + kBlockM - 1) / kBlockM, batch_size, num_heads}, opts.dtype(torch::kInt32));
     params.dq_semaphore = dq_semaphore.data_ptr<int>();
+    at::Tensor dk_semaphore, dv_semaphore;
     if (num_heads_k != num_heads && params.deterministic) {
         // TODO: maybe also zero'ed out dk_semaphore and dv_semaphore in the backward preprocess kernel
-        at::Tensor dk_semaphore = torch::zeros({(seqlen_k + kBlockN - 1) / kBlockN, batch_size, num_heads_k}, opts.dtype(torch::kInt32));
-        at::Tensor dv_semaphore = torch::zeros({(seqlen_k + kBlockN - 1) / kBlockN, batch_size, num_heads_k}, opts.dtype(torch::kInt32));
+        dk_semaphore = torch::zeros({(seqlen_k + kBlockN - 1) / kBlockN, batch_size, num_heads_k}, opts.dtype(torch::kInt32));
+        dv_semaphore = torch::zeros({(seqlen_k + kBlockN - 1) / kBlockN, batch_size, num_heads_k}, opts.dtype(torch::kInt32));
         params.dk_semaphore = dk_semaphore.data_ptr<int>();
         params.dv_semaphore = dv_semaphore.data_ptr<int>();
     }
diff --git a/hopper/flash_api_stable.cpp b/hopper/flash_api_stable.cpp
index 5ae58bdd129..9759af86e08 100644
--- a/hopper/flash_api_stable.cpp
+++ b/hopper/flash_api_stable.cpp
@@ -1610,10 +1610,11 @@ std::tuple<Tensor, Tensor, Tensor, Tensor, Tensor> mha_bwd(
     // Will be zero'ed out in the backward preprocess kernel
     Tensor dq_semaphore = torch::stable::new_empty(q, {(seqlen_q + kBlockM - 1) / kBlockM, batch_size, num_heads}, std::make_optional(torch::headeronly::ScalarType::Int));
     params.dq_semaphore = static_cast<int*>(dq_semaphore.data_ptr());
+    Tensor dk_semaphore, dv_semaphore;
     if (num_heads_k != num_heads && params.deterministic) {
         // TODO: maybe also zero'ed out dk_semaphore and dv_semaphore in the backward preprocess kernel
-        Tensor dk_semaphore = torch::stable::new_zeros(q, {(seqlen_k + kBlockN - 1) / kBlockN, batch_size, num_heads_k}, std::make_optional(torch::headeronly::ScalarType::Int));
-        Tensor dv_semaphore = torch::stable::new_zeros(q, {(seqlen_k + kBlockN - 1) / kBlockN, batch_size, num_heads_k}, std::make_optional(torch::headeronly::ScalarType::Int));
+        dk_semaphore = torch::stable::new_zeros(q, {(seqlen_k + kBlockN - 1) / kBlockN, batch_size, num_heads_k}, std::make_optional(torch::headeronly::ScalarType::Int));
+        dv_semaphore = torch::stable::new_zeros(q, {(seqlen_k + kBlockN - 1) / kBlockN, batch_size, num_heads_k}, std::make_optional(torch::headeronly::ScalarType::Int));
         params.dk_semaphore = static_cast<int*>(dk_semaphore.data_ptr());
         params.dv_semaphore = static_cast<int*>(dv_semaphore.data_ptr());
     }