From: Jiazi Li <jqqlijiazi@xxxxxxxxx> In the following code, the second call to the mas_node_count will return -ENOMEM: mas_node_count(mas, MAPLE_ALLOC_SLOTS + 1); mas_node_count(mas, MAPLE_ALLOC_SLOTS * 2 + 2); This is because there may be some full maple_alloc node in current maple state. Use full maple_alloc node will make max_req equal to 0. And it leads to mt_alloc_bulk return 0. As a result, mas_node_count set mas.node to MA_ERROR(-ENOMEM). Find a non-full maple_alloc node, and if necessary, use this non-full node in the next while loop. Fixes: 54a611b60590 ("Maple Tree: add new data structure") Suggested-by: Liam R. Howlett <Liam.Howlett@xxxxxxxxxx> Signed-off-by: Jiazi Li <jqqlijiazi@xxxxxxxxx> Signed-off-by: Liam R. Howlett <Liam.Howlett@xxxxxxxxxx> --- lib/maple_tree.c | 5 ++++- 1 file changed, 4 insertions(+), 1 deletion(-) diff --git a/lib/maple_tree.c b/lib/maple_tree.c index 634d49e39a02..fe5c6fab26c3 100644 --- a/lib/maple_tree.c +++ b/lib/maple_tree.c @@ -1272,7 +1272,10 @@ static inline void mas_alloc_nodes(struct ma_state *mas, gfp_t gfp) node->node_count += count; allocated += count; - node = node->slot[0]; + /* find a non-full node*/ + do { + node = node->slot[0]; + } while (unlikely(node->node_count == MAPLE_ALLOC_SLOTS)); requested -= count; } mas->alloc->total = allocated; -- 2.43.0