diff --git a/net.c b/net.c
index 88934df..a1bf49f 100644
--- a/net.c
+++ b/net.c
@@ -840,7 +840,7 @@
 /* magic number, but compiler will warn if too small */
 #define NET_MAX_DESC 20
 
-static struct {
+static const struct {
     const char *type;
     net_client_init_func init;
     QemuOptDesc desc[NET_MAX_DESC];
diff --git a/qemu-option.c b/qemu-option.c
index a52a4c4..de40bff 100644
--- a/qemu-option.c
+++ b/qemu-option.c
@@ -470,7 +470,7 @@
     const char   *name;
     const char   *str;
 
-    QemuOptDesc  *desc;
+    const QemuOptDesc *desc;
     union {
         int      boolean;
         uint64_t uint;
@@ -565,7 +565,7 @@
 int qemu_opt_set(QemuOpts *opts, const char *name, const char *value)
 {
     QemuOpt *opt;
-    QemuOptDesc *desc = opts->list->desc;
+    const QemuOptDesc *desc = opts->list->desc;
     int i;
 
     for (i = 0; desc[i].name != NULL; i++) {
@@ -777,7 +777,7 @@
 /* Validate parsed opts against descriptions where no
  * descriptions were provided in the QemuOptsList.
  */
-int qemu_opts_validate(QemuOpts *opts, QemuOptDesc *desc)
+int qemu_opts_validate(QemuOpts *opts, const QemuOptDesc *desc)
 {
     QemuOpt *opt;
 
diff --git a/qemu-option.h b/qemu-option.h
index 666b666..f3f1de7 100644
--- a/qemu-option.h
+++ b/qemu-option.h
@@ -115,7 +115,7 @@
                   const char *name, const char *value);
 const char *qemu_opts_id(QemuOpts *opts);
 void qemu_opts_del(QemuOpts *opts);
-int qemu_opts_validate(QemuOpts *opts, QemuOptDesc *desc);
+int qemu_opts_validate(QemuOpts *opts, const QemuOptDesc *desc);
 int qemu_opts_do_parse(QemuOpts *opts, const char *params, const char *firstname);
 QemuOpts *qemu_opts_parse(QemuOptsList *list, const char *params, const char *firstname);