diff --git a/drivers/char/random.c b/drivers/char/random.c
index 54ca8b23cde3f1aa5550d2806087300227531070..4ec04a754733baed5dd8595256a9c7998965d323 100644
--- a/drivers/char/random.c
+++ b/drivers/char/random.c
@@ -1260,10 +1260,15 @@ static int proc_do_uuid(ctl_table *table, int write,
 	uuid = table->data;
 	if (!uuid) {
 		uuid = tmp_uuid;
-		uuid[8] = 0;
-	}
-	if (uuid[8] == 0)
 		generate_random_uuid(uuid);
+	} else {
+		static DEFINE_SPINLOCK(bootid_spinlock);
+
+		spin_lock(&bootid_spinlock);
+		if (!uuid[8])
+			generate_random_uuid(uuid);
+		spin_unlock(&bootid_spinlock);
+	}
 
 	sprintf(buf, "%pU", uuid);