diff --git a/sys/src/9/port/segment.c b/sys/src/9/port/segment.c
index ef1c254c5..cd48d52b4 100644
--- a/sys/src/9/port/segment.c
+++ b/sys/src/9/port/segment.c
@@ -66,7 +66,6 @@ newseg(int type, uintptr base, ulong size)
 
 	mapsize = ROUND(size, PTEPERTAB)/PTEPERTAB;
 	if(mapsize > nelem(s->ssegmap)){
-		mapsize *= 2;
 		if(mapsize > (SEGMAPSIZE*PTEPERTAB))
 			mapsize = (SEGMAPSIZE*PTEPERTAB);
 		s->map = smalloc(mapsize*sizeof(Pte*));