1 files changed, 1 insertions, 1 deletions

diff --git a/drivers/xen/xen-pciback/conf_space_header.c b/drivers/xen/xen-pciback/conf_space_header.c
index da3cbdfcb5dc..f14b30f71464 100644
--- a/drivers/xen/xen-pciback/conf_space_header.c
+++ b/drivers/xen/xen-pciback/conf_space_header.c
@@ -187,7 +187,7 @@ static inline void read_dev_bar(struct pci_dev *dev,
 
         bar_info->val = res[pos].start |
                         (res[pos].flags & PCI_REGION_FLAG_MASK);
-        bar_info->len_val = res[pos].end - res[pos].start + 1;
+        bar_info->len_val = resource_size(&res[pos]);
 }
 
 static void *bar_init(struct pci_dev *dev, int offset)