On Fri, 2013-07-26 at 12:47 -0400, Neil Horman wrote: > atl1c uses netdev_alloc_skb to refill its rx dma ring, but that call makes no > guarantees about the suitability of the memory for use in DMA. As a result > we've gotten reports of atl1c drivers occasionally hanging and needing to be > reset: > https://bugzilla.kernel.org/show_bug.cgi?id=54021 > > Fix this by modifying the call to use the internal version __netdev_alloc_skb, > where you can set the gfp_mask explicitly to include GFP_DMA.
This is a really bad idea. GFP_DMA means allocation from the ISA DMA region (< 16 MB). pci_map_single() takes care of allocating a bounce buffer if necessary. Ben. > Tested by two reporters in the above bug, who have the hardware to validate > it. > Both report immediate cessation of the problem with this patch > > Signed-off-by: Neil Horman <[email protected]> > CC: Jay Cliburn <[email protected]> > CC: "David S. Miller" <[email protected]> > CC: [email protected] > Tested-by: Luis Henrix <[email protected]> > Tested-by: Vincent Alquier <[email protected]> > --- > drivers/net/ethernet/atheros/atl1c/atl1c_main.c | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) > > diff --git a/drivers/net/ethernet/atheros/atl1c/atl1c_main.c > b/drivers/net/ethernet/atheros/atl1c/atl1c_main.c > index 786a874..d5e38d1 100644 > --- a/drivers/net/ethernet/atheros/atl1c/atl1c_main.c > +++ b/drivers/net/ethernet/atheros/atl1c/atl1c_main.c > @@ -1660,7 +1660,7 @@ static int atl1c_alloc_rx_buffer(struct atl1c_adapter > *adapter) > while (next_info->flags & ATL1C_BUFFER_FREE) { > rfd_desc = ATL1C_RFD_DESC(rfd_ring, rfd_next_to_use); > > - skb = netdev_alloc_skb(adapter->netdev, adapter->rx_buffer_len); > + skb = __netdev_alloc_skb(adapter->netdev, > adapter->rx_buffer_len, GFP_ATOMIC|GFP_DMA); > if (unlikely(!skb)) { > if (netif_msg_rx_err(adapter)) > dev_warn(&pdev->dev, "alloc rx buffer > failed\n"); -- Ben Hutchings, Staff Engineer, Solarflare Not speaking for my employer; that's the marketing department's job. They asked us to note that Solarflare product names are trademarked. -- To unsubscribe from this list: send the line "unsubscribe stable" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html
