From 920309086652651c7d59791e5b83e2f10112b293 Mon Sep 17 00:00:00 2001 From: Soren Brinkmann Date: Tue, 4 Mar 2014 08:46:39 -0800 Subject: [PATCH] net: macb: Check DMA mappings for error With CONFIG_DMA_API_DEBUG enabled the following warning is printed: WARNING: CPU: 0 PID: 619 at lib/dma-debug.c:1101 check_unmap+0x758/0x894() macb e000b000.ethernet: DMA-API: device driver failed to check map error[device address=0x000000002d171c02] [size=322 bytes] [mapped as single] Modules linked in: CPU: 0 PID: 619 Comm: udhcpc Not tainted 3.14.0-rc3-xilinx-00219-gd158fc7f36a2 #63 [] (unwind_backtrace) from [] (show_stack+0x10/0x14) [] (show_stack) from [] (dump_stack+0x7c/0xc8) [] (dump_stack) from [] (warn_slowpath_common+0x60/0x84) [] (warn_slowpath_common) from [] (warn_slowpath_fmt+0x2c/0x3c) [] (warn_slowpath_fmt) from [] (check_unmap+0x758/0x894) [] (check_unmap) from [] (debug_dma_unmap_page+0x64/0x70) [] (debug_dma_unmap_page) from [] (macb_interrupt+0x1f8/0x2dc) [] (macb_interrupt) from [] (handle_irq_event_percpu+0x2c/0x178) [] (handle_irq_event_percpu) from [] (handle_irq_event+0x3c/0x5c) [] (handle_irq_event) from [] (handle_fasteoi_irq+0xb8/0x100) [] (handle_fasteoi_irq) from [] (generic_handle_irq+0x20/0x30) [] (generic_handle_irq) from [] (handle_IRQ+0x64/0x8c) [] (handle_IRQ) from [] (gic_handle_irq+0x3c/0x60) [] (gic_handle_irq) from [] (__irq_svc+0x44/0x78) Exception stack(0xed197f60 to 0xed197fa8) 7f60: 00000134 60000013 bd94362e bd94362e be96b37c 00000014 fffffd72 00000122 7f80: c000ebe4 ed196000 00000000 00000011 c032c0d8 ed197fa8 c0064008 c000ea20 7fa0: 60000013 ffffffff [] (__irq_svc) from [] (ret_fast_syscall+0x0/0x48) ---[ end trace 478f921d0d542d1e ]--- Mapped at: [] debug_dma_map_page+0x48/0x11c [] macb_start_xmit+0x184/0x2a8 [] dev_hard_start_xmit+0x334/0x470 [] sch_direct_xmit+0x78/0x2f8 [] __dev_queue_xmit+0x318/0x708 due to missing checks of the dma mapping. Add the appropriate checks to fix this. Signed-off-by: Soren Brinkmann Reviewed-by: Ben Hutchings Signed-off-by: David S. Miller --- drivers/net/ethernet/cadence/macb.c | 14 ++++++++++++-- 1 file changed, 12 insertions(+), 2 deletions(-) diff --git a/drivers/net/ethernet/cadence/macb.c b/drivers/net/ethernet/cadence/macb.c index 3190d38e16fb..1f03e2041e86 100644 --- a/drivers/net/ethernet/cadence/macb.c +++ b/drivers/net/ethernet/cadence/macb.c @@ -632,11 +632,16 @@ static void gem_rx_refill(struct macb *bp) "Unable to allocate sk_buff\n"); break; } - bp->rx_skbuff[entry] = skb; /* now fill corresponding descriptor entry */ paddr = dma_map_single(&bp->pdev->dev, skb->data, bp->rx_buffer_size, DMA_FROM_DEVICE); + if (dma_mapping_error(&bp->pdev->dev, paddr)) { + dev_kfree_skb(skb); + break; + } + + bp->rx_skbuff[entry] = skb; if (entry == RX_RING_SIZE - 1) paddr |= MACB_BIT(RX_WRAP); @@ -1036,11 +1041,15 @@ static int macb_start_xmit(struct sk_buff *skb, struct net_device *dev) } entry = macb_tx_ring_wrap(bp->tx_head); - bp->tx_head++; netdev_vdbg(bp->dev, "Allocated ring entry %u\n", entry); mapping = dma_map_single(&bp->pdev->dev, skb->data, len, DMA_TO_DEVICE); + if (dma_mapping_error(&bp->pdev->dev, mapping)) { + kfree_skb(skb); + goto unlock; + } + bp->tx_head++; tx_skb = &bp->tx_skb[entry]; tx_skb->skb = skb; tx_skb->mapping = mapping; @@ -1066,6 +1075,7 @@ static int macb_start_xmit(struct sk_buff *skb, struct net_device *dev) if (CIRC_SPACE(bp->tx_head, bp->tx_tail, TX_RING_SIZE) < 1) netif_stop_queue(dev); +unlock: spin_unlock_irqrestore(&bp->lock, flags); return NETDEV_TX_OK; -- 2.20.1