diff --git a/torch_geometric/utils/_subgraph.py b/torch_geometric/utils/_subgraph.py
index 7540cc9f2c26..7d2a69ec4e3a 100644
--- a/torch_geometric/utils/_subgraph.py
+++ b/torch_geometric/utils/_subgraph.py
@@ -138,7 +138,7 @@ def subgraph(
     else:
         num_nodes = subset.size(0)
         node_mask = subset
-        subset = node_mask.nonzero().view(-1)
+        subset = node_mask.nonzero_static(size=num_nodes).view(-1)
 
     edge_mask = node_mask[edge_index[0]] & node_mask[edge_index[1]]
     edge_index = edge_index[:, edge_mask]
@@ -219,7 +219,7 @@ def bipartite_subgraph(
     else:
         src_size = src_subset.size(0)
         src_node_mask = src_subset
-        src_subset = src_subset.nonzero().view(-1)
+        src_subset = src_subset.nonzero_static(size=src_size).view(-1)
 
     if dst_subset.dtype != torch.bool:
         dst_size = int(edge_index[1].max()) + 1 if size is None else size[1]
@@ -227,7 +227,7 @@ def bipartite_subgraph(
     else:
         dst_size = dst_subset.size(0)
         dst_node_mask = dst_subset
-        dst_subset = dst_subset.nonzero().view(-1)
+        dst_subset = dst_subset.nonzero_static(size=dst_size).view(-1)
 
     edge_mask = src_node_mask[edge_index[0]] & dst_node_mask[edge_index[1]]
     edge_index = edge_index[:, edge_mask]
diff --git a/torch_geometric/utils/mask.py b/torch_geometric/utils/mask.py
index 378e98d3d946..2895058660f2 100644
--- a/torch_geometric/utils/mask.py
+++ b/torch_geometric/utils/mask.py
@@ -57,7 +57,7 @@ def index_to_mask(index: Tensor, size: Optional[int] = None) -> Tensor:
     index = index.view(-1)
     size = int(index.max()) + 1 if size is None else size
     mask = index.new_zeros(size, dtype=torch.bool)
-    mask[index] = True
+    mask.scatter_(0, index, True)
     return mask