diff --git a/include/sys/prctl.h b/include/sys/prctl.h
index d9c846e9..4b9fcc05 100644
--- a/include/sys/prctl.h
+++ b/include/sys/prctl.h
@@ -158,6 +158,9 @@ struct prctl_mm_map {
 #define PR_GET_TAGGED_ADDR_CTRL 56
 #define PR_TAGGED_ADDR_ENABLE (1UL << 0)
 
+#define PR_SET_IO_FLUSHER 57
+#define PR_GET_IO_FLUSHER 58
+
 int prctl (int, ...);
 
 #ifdef __cplusplus