RDMA/nes: Fix for unlinking skbs from empty list

Signed-off-by: Tatyana Nikolova <Tatyana.E.Nikolova@intel.com>
Signed-off-by: Roland Dreier <roland@purestorage.com>

1 files changed, 7 insertions, 4 deletions

diff --git a/drivers/infiniband/hw/nes/nes_mgt.c b/drivers/infiniband/hw/nes/nes_mgt.c
index 8cf74fd0c44f..1f5d69e7793a 100644
--- a/drivers/infiniband/hw/nes/nes_mgt.c
+++ b/drivers/infiniband/hw/nes/nes_mgt.c
@@ -210,6 +210,9 @@ static struct sk_buff *nes_get_next_skb(struct nes_device *nesdev, struct nes_qp
         }
 
         while (1) {
+                if (skb_queue_empty(&nesqp->pau_list))
+                        goto out;
+
                 seq = nes_get_seq(skb, ack, wnd, fin_rcvd, rst_rcvd);
                 if (seq == nextseq) {
                         if (skb->len || processacks)
@@ -218,14 +221,13 @@ static struct sk_buff *nes_get_next_skb(struct nes_device *nesdev, struct nes_qp
                         goto out;
                 }
 
-                if (skb->next == (struct sk_buff *)&nesqp->pau_list)
-                        goto out;
-
                 old_skb = skb;
                 skb = skb->next;
                 skb_unlink(old_skb, &nesqp->pau_list);
                 nes_mgt_free_skb(nesdev, old_skb, PCI_DMA_TODEVICE);
                 nes_rem_ref_cm_node(nesqp->cm_node);
+                if (skb == (struct sk_buff *)&nesqp->pau_list)
+                        goto out;
         }
         return skb;
 
@@ -384,7 +386,8 @@ static int get_fpdu_info(struct nes_device *nesdev, struct nes_qp *nesqp,
                 if (frags[i].skb->len == 0) {
                         /* Pull skb off the list - it will be freed in the callback */
                         spin_lock_irqsave(&nesqp->pau_lock, flags);
-                        skb_unlink(frags[i].skb, &nesqp->pau_list);
+                        if (!skb_queue_empty(&nesqp->pau_list))
+                                skb_unlink(frags[i].skb, &nesqp->pau_list);
                         spin_unlock_irqrestore(&nesqp->pau_lock, flags);
                 } else {
                         /* Last skb still has data so update the seq */