xhci: don't finish a TD if we get a short transfer event mid TD

If the difference is big enough between the bytes asked and received
in a bulk transfer we can get a short transfer event pointing to a TRB in
the middle of the TD. We don't want to handle the TD yet as we will anyway
receive a new event for the last TRB in the TD.

Hold off from finishing the TD and removing it from the list until we
receive an event for the last TRB in the TD

Cc: stable <stable@vger.kernel.org>
Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/drivers/usb/host/xhci-ring.c b/drivers/usb/host/xhci-ring.c
index 43291f93afeb59a90a3b39cbb045a26b3bd1ad5b..79e89e6aef73b7f06f2028d180d92b2f4b010ae1 100644 (file)
--- a/drivers/usb/host/xhci-ring.c
+++ b/drivers/usb/host/xhci-ring.c
@@ -2191,6 +2191,10 @@ static int process_bulk_intr_td(struct xhci_hcd *xhci, struct xhci_td *td,
                }
        /* Fast path - was this the last TRB in the TD for this URB? */
        } else if (event_trb == td->last_trb) {
+               if (td->urb_length_set && trb_comp_code == COMP_SHORT_TX)
+                       return finish_td(xhci, td, event_trb, event, ep,
+                                        status, false);
+
                if (EVENT_TRB_LEN(le32_to_cpu(event->transfer_len)) != 0) {
                        td->urb->actual_length =
                                td->urb->transfer_buffer_length -
@@ -2242,6 +2246,12 @@ static int process_bulk_intr_td(struct xhci_hcd *xhci, struct xhci_td *td,
                        td->urb->actual_length +=
                                TRB_LEN(le32_to_cpu(cur_trb->generic.field[2])) -
                                EVENT_TRB_LEN(le32_to_cpu(event->transfer_len));
+
+               if (trb_comp_code == COMP_SHORT_TX) {
+                       xhci_dbg(xhci, "mid bulk/intr SP, wait for last TRB event\n");
+                       td->urb_length_set = true;
+                       return 0;
+               }
        }
 
        return finish_td(xhci, td, event_trb, event, ep, status, false);