[ 50/83] iwlwifi: handle DMA mapping failures
From: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Date: 2012-11-22 18:40:49
Also in:
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3.6-stable review patch. If anyone has any objections, please let me know.
------------------
From: Johannes Berg <redacted>
commit 7c34158231b2eda8dcbd297be2bb1559e69cb433 upstream.
The RX replenish code doesn't handle DMA mapping failures,
which will cause issues if there actually is a failure. This
was reported by Shuah Khan who found a DMA mapping framework
warning ("device driver failed to check map error").
Reported-by: Shuah Khan <redacted>
Reviewed-by: Emmanuel Grumbach <redacted>
Signed-off-by: Johannes Berg <redacted>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
drivers/net/wireless/iwlwifi/pcie/rx.c | 23 +++++++++++++++++++++--
1 file changed, 21 insertions(+), 2 deletions(-)
--- a/drivers/net/wireless/iwlwifi/pcie/rx.c
+++ b/drivers/net/wireless/iwlwifi/pcie/rx.c@@ -314,6 +314,14 @@ static void iwlagn_rx_allocate(struct iw dma_map_page(trans->dev, page, 0, PAGE_SIZE << trans_pcie->rx_page_order, DMA_FROM_DEVICE); + if (dma_mapping_error(trans->dev, rxb->page_dma)) { + rxb->page = NULL; + spin_lock_irqsave(&rxq->lock, flags); + list_add(&rxb->list, &rxq->rx_used); + spin_unlock_irqrestore(&rxq->lock, flags); + __free_pages(page, trans_pcie->rx_page_order); + return; + } /* dma address must be no more than 36 bits */ BUG_ON(rxb->page_dma & ~DMA_BIT_MASK(36)); /* and also 256 byte aligned! */
@@ -463,8 +471,19 @@ static void iwl_rx_handle_rxbuf(struct i dma_map_page(trans->dev, rxb->page, 0, PAGE_SIZE << trans_pcie->rx_page_order, DMA_FROM_DEVICE); - list_add_tail(&rxb->list, &rxq->rx_free); - rxq->free_count++; + if (dma_mapping_error(trans->dev, rxb->page_dma)) { + /* + * free the page(s) as well to not break + * the invariant that the items on the used + * list have no page(s) + */ + __free_pages(rxb->page, trans_pcie->rx_page_order); + rxb->page = NULL; + list_add_tail(&rxb->list, &rxq->rx_used); + } else { + list_add_tail(&rxb->list, &rxq->rx_free); + rxq->free_count++; + } } else list_add_tail(&rxb->list, &rxq->rx_used); spin_unlock_irqrestore(&rxq->lock, flags);