diff --git a/include/sys/resource.h b/include/sys/resource.h
index 0ce13783c4..494e9a1d28 100644
--- a/include/sys/resource.h
+++ b/include/sys/resource.h
@@ -57,6 +57,7 @@
 #define RLIMIT_NOFILE   5           /* Limit on number of open files */
 #define RLIMIT_STACK    6           /* Limit on stack size */
 #define RLIMIT_AS       7           /* Limit on address space size */
+#define RLIMIT_MEMLOCK  8           /* Limit on memory use */
 
 #if defined(CONFIG_FS_LARGEFILE)
 #  define RLIM_INFINITY    UINT64_MAX /* No limit */