[openib-general] segmentation fault with ibv_pingpong

[Roland Dreier]

OK, I think I see the problem.  Can you please try this patch and let
me know if it helps?

Thanks,
  Roland

--- infiniband/hw/mthca/mthca_memfree.c	(revision 2156)
+++ infiniband/hw/mthca/mthca_memfree.c	(working copy)
@@ -384,6 +384,7 @@ int mthca_map_user_db(struct mthca_dev *
 	if (ret < 0)
 		goto out;
 
+	db_tab->page[i].mem.length = 4096;
 	db_tab->page[i].mem.offset = uaddr & ~PAGE_MASK;
 
 	ret = pci_map_sg(dev->pdev, &db_tab->page[i].mem, 1, PCI_DMA_TODEVICE);