[PATCH] IB/ipath: fix a bug that results in addresses near 0 being written via DMA

We can't tell for sure if any packets are in the infinipath receive buffer
when we shut down a chip port.  Normally this is taken care of by orderly
shutdown, but when processes are terminated, or sending process has a bug, we
can continue to receive packets.  So rather than writing zero to the address
registers for the closing port, we point it at a dummy memory.

Signed-off-by: Dave Olson <dave.olson@qlogic.com>
Signed-off-by: Bryan O'Sullivan <bryan.osullivan@qlogic.com>
Cc: "Michael S. Tsirkin" <mst@mellanox.co.il>
Cc: Roland Dreier <rolandd@cisco.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

1 files changed, 6 insertions, 0 deletions

diff --git a/drivers/infiniband/hw/ipath/ipath_driver.c b/drivers/infiniband/hw/ipath/ipath_driver.c
index 4109913c20a7..f647918db62b 100644
--- a/drivers/infiniband/hw/ipath/ipath_driver.c
+++ b/drivers/infiniband/hw/ipath/ipath_driver.c
@@ -1824,6 +1824,12 @@ static void cleanup_device(struct ipath_devdata *dd)
                                   dd->ipath_pioavailregs_phys);
                 dd->ipath_pioavailregs_dma = NULL;
         }
+        if (dd->ipath_dummy_hdrq) {
+                dma_free_coherent(&dd->pcidev->dev,
+                        dd->ipath_pd[0]->port_rcvhdrq_size,
+                        dd->ipath_dummy_hdrq, dd->ipath_dummy_hdrq_phys);
+                dd->ipath_dummy_hdrq = NULL;
+        }
 
         if (dd->ipath_pageshadow) {
                 struct page **tmpp = dd->ipath_pageshadow;