Do not pass DIRECTMAP_VIRT_END to virt_to_mfn(). It's out of range.

Signed-off-by: Xiaowei Yang <xiaowei.yang@intel.com>
Signed-off-by: Keir Fraser <keir.fraser@citrix.com>

diff --git a/xen/common/page_alloc.c b/xen/common/page_alloc.c
index eb07404e7afc4704eb8fd52ace311077de6e1d6b..830e44cdb47e3a4c707ee3c10a999463e29368f1 100644 (file)
--- a/xen/common/page_alloc.c
+++ b/xen/common/page_alloc.c
@@ -299,7 +299,7 @@ static unsigned long init_node_heap(int node, unsigned long mfn,
     }
 #ifdef DIRECTMAP_VIRT_END
     else if ( nr >= needed &&
-              mfn + needed <= virt_to_mfn(DIRECTMAP_VIRT_END) )
+              (mfn + needed) <= (virt_to_mfn(DIRECTMAP_VIRT_END - 1) + 1) )
     {
         _heap[node] = mfn_to_virt(mfn);
         avail[node] = mfn_to_virt(mfn + needed) - sizeof(**avail) * NR_ZONES;