--- /dev/null
+--- a/include/linux/pagemap.h
++++ b/include/linux/pagemap.h
+@@ -422,7 +422,7 @@ static inline int fault_in_pages_writeab
+
+ static inline int fault_in_pages_readable(const char __user *uaddr, int size)
+ {
+- volatile char c;
++ volatile char c __maybe_unused;
+ int ret;
+
+ if (unlikely(size == 0))