3.14-stable review patch. If anyone has any objections, please let me know. ------------------ From: Feng Tang <feng.tang@xxxxxxxxx> [ Upstream commit 881d0327db37ad917a367c77aff1afa1ee41e0a9 ] Note: This is a verified backported patch for stable 4.4 kernel, and it could also be applied to 4.3/4.2/4.1/3.18/3.16 There is a problem with alx devices, that the network link will be lost in 1-5 minutes after the device is up. >From debugging without datasheet, we found the error always happen when the DMA RX address is set to 0x....fc0, which is very likely to be a HW/silicon problem. This patch will apply rx skb with 64 bytes longer space, and if the allocated skb has a 0x...fc0 address, it will use skb_resever(skb, 64) to advance the address, so that the RX overflow can be avoided. Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=70761 Signed-off-by: Feng Tang <feng.tang@xxxxxxxxx> Suggested-by: Eric Dumazet <edumazet@xxxxxxxxxx> Tested-by: Ole Lukoie <olelukoie@xxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- drivers/net/ethernet/atheros/alx/main.c | 7 ++++++- 1 file changed, 6 insertions(+), 1 deletion(-) --- a/drivers/net/ethernet/atheros/alx/main.c +++ b/drivers/net/ethernet/atheros/alx/main.c @@ -86,9 +86,14 @@ static int alx_refill_rx_ring(struct alx while (!cur_buf->skb && next != rxq->read_idx) { struct alx_rfd *rfd = &rxq->rfd[cur]; - skb = __netdev_alloc_skb(alx->dev, alx->rxbuf_size, gfp); + skb = __netdev_alloc_skb(alx->dev, alx->rxbuf_size + 64, gfp); if (!skb) break; + + /* Workround for the HW RX DMA overflow issue */ + if (((unsigned long)skb->data & 0xfff) == 0xfc0) + skb_reserve(skb, 64); + dma = dma_map_single(&alx->hw.pdev->dev, skb->data, alx->rxbuf_size, DMA_FROM_DEVICE); -- To unsubscribe from this list: send the line "unsubscribe stable" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html