spidernet: invalidate unused pointer.

Invalidate a pointer as its pci_unmap'ed; this is a bit of
paranoia to make sure hardware doesn't continue trying to
DMA to it.

Signed-off-by: Linas Vepstas <linas@austin.ibm.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>

1 files changed, 5 insertions, 2 deletions

diff --git a/drivers/net/spider_net.c b/drivers/net/spider_net.c
index 4d180072de4d..628efc01f273 100644
--- a/drivers/net/spider_net.c
+++ b/drivers/net/spider_net.c
@@ -1187,6 +1187,7 @@ spider_net_decode_one_descr(struct spider_net_card *card)
         struct spider_net_descr_chain *chain = &card->rx_chain;
         struct spider_net_descr *descr = chain->tail;
         struct spider_net_hw_descr *hwdescr = descr->hwdescr;
+        u32 hw_buf_addr;
         int status;
 
         status = spider_net_get_descr_status(hwdescr);
@@ -1200,7 +1201,9 @@ spider_net_decode_one_descr(struct spider_net_card *card)
         chain->tail = descr->next;
 
         /* unmap descriptor */
-        pci_unmap_single(card->pdev, hwdescr->buf_addr,
+        hw_buf_addr = hwdescr->buf_addr;
+        hwdescr->buf_addr = 0xffffffff;
+        pci_unmap_single(card->pdev, hw_buf_addr,
                         SPIDER_NET_MAX_FRAME, PCI_DMA_FROMDEVICE);
 
         if ( (status == SPIDER_NET_DESCR_RESPONSE_ERROR) ||
@@ -1235,7 +1238,7 @@ spider_net_decode_one_descr(struct spider_net_card *card)
         if (hwdescr->dmac_cmd_status & 0xfcf4) {
                 dev_err(&card->netdev->dev, "bad status, cmd_status=x%08x\n",
                                hwdescr->dmac_cmd_status);
-                pr_err("buf_addr=x%08x\n", hwdescr->buf_addr);
+                pr_err("buf_addr=x%08x\n", hw_buf_addr);
                 pr_err("buf_size=x%08x\n", hwdescr->buf_size);
                 pr_err("next_descr_addr=x%08x\n", hwdescr->next_descr_addr);
                 pr_err("result_size=x%08x\n", hwdescr->result_size);