From: Eran Liberty <liberty@xxxxxxxxxxxx>This code has proved to be insufficient and produce skb_over_panic. The proposed patch fix this.
Date: Thu, 24 Jun 2010 12:53:23 +0300
Fix possible skb_over_panic event in Freescale's "gianfar" driver.
The skb_over_panic occurs due to calling skb_put() within
gfar_clean_rx_ring(). This happens if (and only if) shortly prior to
the event and a few lined above the skb_put(), an skb was queued back
to the priv->rx_recycle queue due to RXBD_LAST or RXBD_ERR status.
The skb is queued without properly re-setting its state.
The patch properly reset the skb state.
I have tested this patch on MPC8548 based product and asserted it
avoided the skb_over_panic event.
Signed-off-by: Eran Liberty <liberty@xxxxxxxxxxxx>
Eran, this seems to be fixed already. The code in the current
tree now reads:
/*
* We need to un-reserve() the skb to what it
* was before gfar_new_skb() re-aligned
* it to an RXBUF_ALIGNMENT boundary
* before we put the skb back on the
* recycle list.
*/
skb_reserve(skb, -GFAR_CB(skb)->alignamount);
__skb_queue_head(&priv->rx_recycle, skb);