diff --git a/[refs] b/[refs]
index 1e40b64b80de..f53ce0d18fb9 100644
--- a/[refs]
+++ b/[refs]
@@ -1,2 +1,2 @@
 ---
-refs/heads/master: ae21ee65e8bc228416bbcc8a1da01c56a847a60c
+refs/heads/master: df0e97c6f1f2fdca686036998fe816cefd8e27d7
diff --git a/trunk/drivers/pci/probe.c b/trunk/drivers/pci/probe.c
index aac5b156a5c5..bb2cc39b64ff 100644
--- a/trunk/drivers/pci/probe.c
+++ b/trunk/drivers/pci/probe.c
@@ -11,6 +11,7 @@
 #include <linux/cpumask.h>
 #include <linux/pci-aspm.h>
 #include <linux/iommu.h>
+#include <xen/xen.h>
 #include "pci.h"
 
 #define CARDBUS_LATENCY_TIMER	176	/* secondary latency timer */
@@ -1007,7 +1008,7 @@ static void pci_init_capabilities(struct pci_dev *dev)
 	pci_iov_init(dev);
 
 	/* Enable ACS P2P upstream forwarding */
-	if (iommu_found())
+	if (iommu_found() || xen_initial_domain())
 		pci_enable_acs(dev);
 }