diff --git a/mm/percpu.c b/mm/percpu.c
index 867efd3..af3dd27 100644
--- a/mm/percpu.c
+++ b/mm/percpu.c
@@ -974,6 +974,7 @@
 	if (list_empty(&pcpu_slot[pcpu_nr_slots - 1])) {
 		chunk = pcpu_create_chunk();
 		if (!chunk) {
+			mutex_unlock(&pcpu_alloc_mutex);
 			err = "failed to allocate new chunk";
 			goto fail;
 		}