[PATCH] Fix buglets in mpc5200 FEC code that are corrupting memory.

Jon Smirl jonsmirl at gmail.com
Fri Nov 9 16:31:35 EST 2007

This is the reason I couldn't get user space started or connect to my
nfs server. Patch is against current linus git.

mpc5200 fec driver is corrupting memory. This patch fixes two bugs
where the wrong skb buffer was being referenced.

Signed-off-by: Jon Smirl <jonsmirl at gmail.com>


 drivers/net/fec_mpc52xx.c |    4 ++--
 1 files changed, 2 insertions(+), 2 deletions(-)

diff --git a/drivers/net/fec_mpc52xx.c b/drivers/net/fec_mpc52xx.c
index a8a0ee2..ddfcc0b 100644
--- a/drivers/net/fec_mpc52xx.c
+++ b/drivers/net/fec_mpc52xx.c
@@ -422,7 +422,7 @@ static irqreturn_t mpc52xx_fec_rx_interrupt(int
irq, void *dev_id)

 		rskb = bcom_retrieve_buffer(priv->rx_dmatsk, &status,
 				(struct bcom_bd **)&bd);
-		dma_unmap_single(&dev->dev, bd->skb_pa, skb->len, DMA_FROM_DEVICE);
+		dma_unmap_single(&dev->dev, bd->skb_pa, rskb->len, DMA_FROM_DEVICE);

 		/* Test for errors in received frame */
 		if (status & BCOM_FEC_RX_BD_ERRORS) {
@@ -467,7 +467,7 @@ static irqreturn_t mpc52xx_fec_rx_interrupt(int
irq, void *dev_id)

 		bd->status = FEC_RX_BUFFER_SIZE;
-		bd->skb_pa = dma_map_single(&dev->dev, rskb->data,
+		bd->skb_pa = dma_map_single(&dev->dev, skb->data,

 		bcom_submit_next_buffer(priv->rx_dmatsk, skb);

Jon Smirl
jonsmirl at gmail.com

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