ixgb: fix bug when freeing resources

PATCH New Jeff Kirsher 1 participant 1 message Oct 1, 2008

Subsystems (2)

Networking Network drivers

lore

Share & tools

lore

Jeff Kirsher

author

2008-10-01 21:59 UTC #0 lore raw

PATCH 1/1 ixgb: fix bug when freeing resources

From: Jesse Brandeburg <[email protected]>

It was pointed out by Breno Leitao <[email protected]> that ixgb would crash on PPC when an IOMMU was in use, if change_mtu was called.

It appears to be a pretty simple issue in the driver that wasn't discovered because most systems don't run with an IOMMU. The driver needs to only unmap buffers that are mapped (duh).

Signed-off-by Jesse Brandeburg <[email protected]>

Signed-off-by Jeff Kirsher <[email protected]>

CC Breno Leitao <[email protected]>

---

 drivers/net/ixgb/ixgb_main.c |    8 +++++---
 1 files changed, 5 insertions(+), 3 deletions(-)

drivers/net/ixgb/ixgb_main.c +5 -3

index aa75385..be3c7dc 100644
@@ -977,15 +977,17 @@ ixgb_clean_rx_ring(struct ixgb_adapter *adapter)
 
 	for (i = 0; i < rx_ring->count; i++) {
 		buffer_info = &rx_ring->buffer_info[i];
-		if (buffer_info->skb) {
-
+		if (buffer_info->dma) {
 			pci_unmap_single(pdev,
 					 buffer_info->dma,
 					 buffer_info->length,
 					 PCI_DMA_FROMDEVICE);
+			buffer_info->dma = 0;
+			buffer_info->length = 0;
+		}
 
+		if (buffer_info->skb) {
 			dev_kfree_skb(buffer_info->skb);
-
 			buffer_info->skb = NULL;
 		}
 	}