diff --git a/block/blk-iocost.c b/block/blk-iocost.c
index 5a6098a3db57e065eb5dcff135178cdf19219cbf..9dc9323f84ac1c1f722ef45047189d8215a50ef3 100644
--- a/block/blk-iocost.c
+++ b/block/blk-iocost.c
@@ -648,7 +648,7 @@ static const struct ioc_params autop[] = {
  * vrate adjust percentages indexed by ioc->busy_level.  We adjust up on
  * vtime credit shortage and down on device saturation.
  */
-static u32 vrate_adj_pct[] =
+static const u32 vrate_adj_pct[] =
 	{ 0, 0, 0, 0,
 	  1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1,
 	  2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2,