diff --git a/drivers/nvme/target/auth.c b/drivers/nvme/target/auth.c
index bf92435c783c..716a10ca91d1 100644
--- a/drivers/nvme/target/auth.c
+++ b/drivers/nvme/target/auth.c
@@ -488,7 +488,7 @@ int nvmet_auth_ctrl_exponential(struct nvmet_req *req,
 		return -ENOKEY;
 	}
 	if (buf_size != ctrl->dh_keysize) {
-		pr_warn("ctrl %d DH public key size mismatch, need %lu is %d\n",
+		pr_warn("ctrl %d DH public key size mismatch, need %zu is %d\n",
 			ctrl->cntlid, ctrl->dh_keysize, buf_size);
 		ret = -EINVAL;
 	} else {