diff --git a/tools/testing/selftests/mm/vm_util.h b/tools/testing/selftests/mm/vm_util.h
index c7fa61f0dff8..0c603bec5e20 100644
--- a/tools/testing/selftests/mm/vm_util.h
+++ b/tools/testing/selftests/mm/vm_util.h
@@ -3,7 +3,7 @@
 #include <stdbool.h>
 #include <sys/mman.h>
 #include <err.h>
-#include <string.h> /* ffsl() */
+#include <strings.h> /* ffsl() */
 #include <unistd.h> /* _SC_PAGESIZE */
 
 #define BIT_ULL(nr)                   (1ULL << (nr))