diff --git a/service/ptos/mm/pm.c b/service/ptos/mm/pm.c
index ce5c609..bcef43f 100644
--- a/service/ptos/mm/pm.c
+++ b/service/ptos/mm/pm.c
@@ -221,7 +221,7 @@ MmRequestFrame(VOID)
     Pfd = PmPfdListPop(&AvlList);
     RtlMemSet(Pfd, 0, PAGESIZE);
 
-    PhysicalBase = (UPTR)Pfd;
+    PhysicalBase = VMA_TO_PMA(Pfd);
     return ADDRESS_TO_PFN(PhysicalBase);
 }