diff --git a/drivers/infiniband/hw/mlx5/mr.c b/drivers/infiniband/hw/mlx5/mr.c
index 0f90086327fc2..81644bb750548 100644
--- a/drivers/infiniband/hw/mlx5/mr.c
+++ b/drivers/infiniband/hw/mlx5/mr.c
@@ -49,6 +49,7 @@ enum {
 	MAX_PENDING_REG_MR = 8,
 };
 
+#define MLX5_MR_CACHE_PERSISTENT_ENTRY_MIN_DESCS 4
 #define MLX5_UMR_ALIGN 2048
 
 static void
@@ -662,6 +663,7 @@ mkey_cache_ent_from_rb_key(struct mlx5_ib_dev *dev,
 {
 	struct rb_node *node = dev->cache.rb_root.rb_node;
 	struct mlx5_cache_ent *cur, *smallest = NULL;
+	u64 ndescs_limit;
 	int cmp;
 
 	/*
@@ -680,10 +682,18 @@ mkey_cache_ent_from_rb_key(struct mlx5_ib_dev *dev,
 			return cur;
 	}
 
+	/*
+	 * Limit the usage of mkeys larger than twice the required size while
+	 * also allowing the usage of smallest cache entry for small MRs.
+	 */
+	ndescs_limit = max_t(u64, rb_key.ndescs * 2,
+			     MLX5_MR_CACHE_PERSISTENT_ENTRY_MIN_DESCS);
+
 	return (smallest &&
 		smallest->rb_key.access_mode == rb_key.access_mode &&
 		smallest->rb_key.access_flags == rb_key.access_flags &&
-		smallest->rb_key.ats == rb_key.ats) ?
+		smallest->rb_key.ats == rb_key.ats &&
+		smallest->rb_key.ndescs <= ndescs_limit) ?
 		       smallest :
 		       NULL;
 }
@@ -964,7 +974,7 @@ int mlx5_mkey_cache_init(struct mlx5_ib_dev *dev)
 	mlx5_mkey_cache_debugfs_init(dev);
 	mutex_lock(&cache->rb_lock);
 	for (i = 0; i <= mkey_cache_max_order(dev); i++) {
-		rb_key.ndescs = 1 << (i + 2);
+		rb_key.ndescs = MLX5_MR_CACHE_PERSISTENT_ENTRY_MIN_DESCS << i;
 		ent = mlx5r_cache_create_ent_locked(dev, rb_key, true);
 		if (IS_ERR(ent)) {
 			ret = PTR_ERR(ent);