xhci: Avoid BUG() in interrupt context

Change the BUGs in xhci_find_new_dequeue_state() to WARN_ONs, to avoid
bringing down the box if one of them is hit

This patch should be queued for stable kernels back to 2.6.31.

Signed-off-by: Paul Zimmerman <paulz@synopsys.com>
Signed-off-by: Sarah Sharp <sarah.a.sharp@linux.intel.com>
Cc: stable@kernel.org

1 files changed, 9 insertions, 4 deletions

diff --git a/drivers/usb/host/xhci-ring.c b/drivers/usb/host/xhci-ring.c
index 3e8211c1ce5a..2a87231d588d 100644
--- a/drivers/usb/host/xhci-ring.c
+++ b/drivers/usb/host/xhci-ring.c
@@ -474,8 +474,11 @@ void xhci_find_new_dequeue_state(struct xhci_hcd *xhci,
         state->new_deq_seg = find_trb_seg(cur_td->start_seg,
                         dev->eps[ep_index].stopped_trb,
                         &state->new_cycle_state);
-        if (!state->new_deq_seg)
-                BUG();
+        if (!state->new_deq_seg) {
+                WARN_ON(1);
+                return;
+        }
+
         /* Dig out the cycle state saved by the xHC during the stop ep cmd */
         xhci_dbg(xhci, "Finding endpoint context\n");
         ep_ctx = xhci_get_ep_ctx(xhci, dev->out_ctx, ep_index);
@@ -486,8 +489,10 @@ void xhci_find_new_dequeue_state(struct xhci_hcd *xhci,
         state->new_deq_seg = find_trb_seg(state->new_deq_seg,
                         state->new_deq_ptr,
                         &state->new_cycle_state);
-        if (!state->new_deq_seg)
-                BUG();
+        if (!state->new_deq_seg) {
+                WARN_ON(1);
+                return;
+        }
 
         trb = &state->new_deq_ptr->generic;
         if ((trb->field[3] & TRB_TYPE_BITMASK) == TRB_TYPE(TRB_LINK) &&