diff --git a/kernel/trunk/init.inc b/kernel/trunk/init.inc
index 94f64fde5c..54aa7b5978 100644
--- a/kernel/trunk/init.inc
+++ b/kernel/trunk/init.inc
@@ -108,6 +108,7 @@ proc init_mem
            mov [tmp_page_tabs], edx
 
            mov edx, esi
+           and edx, -1024
            cmp edx, (OS_BASE/4096)
            jbe @F
            mov edx, (OS_BASE/4096)