diff --git a/mm/allocpercpu.c b/mm/allocpercpu.c
index 139d5b7..dfdee6a 100644
--- a/mm/allocpercpu.c
+++ b/mm/allocpercpu.c
@@ -31,7 +31,7 @@
  * @__pdata: per-cpu data to depopulate
  * @mask: depopulate per-cpu data for cpu's selected through mask bits
  */
-static void __percpu_depopulate_mask(void *__pdata, cpumask_t *mask)
+static void __percpu_depopulate_mask(void *__pdata, const cpumask_t *mask)
 {
 	int cpu;
 	for_each_cpu_mask_nr(cpu, *mask)