From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Shuah Khan , Emmanuel Grumbach , Johannes Berg , Ben Hutchings , Jianguo Wu Subject: [PATCH 3.4 92/99] iwlwifi: handle DMA mapping failures Date: Fri, 7 Mar 2014 17:08:28 -0800 Message-Id: <20140308010614.515388530@linuxfoundation.org> In-Reply-To: <20140308010611.468206150@linuxfoundation.org> References: <20140308010611.468206150@linuxfoundation.org> MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Sender: linux-kernel-owner@vger.kernel.org List-ID: 3.4-stable review patch. If anyone has any objections, please let me know. ------------------ From: Johannes Berg 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 Reviewed-by: Emmanuel Grumbach Signed-off-by: Johannes Berg [bwh: Backported to 3.2: - Adjust filename, context, indentation - Use bus(trans) instead of trans where necessary - Use hw_params(trans).rx_page_order instead of trans_pcie->rx_page_order] Signed-off-by: Ben Hutchings [wujg: Backported to 3.4: - Adjust context - Use trans instead of bus(trans) - Use hw_params(trans).rx_page_order instead of trans_pcie->rx_page_order] Signed-off-by: Jianguo Wu Signed-off-by: Greg Kroah-Hartman --- drivers/net/wireless/iwlwifi/iwl-trans-pcie-rx.c | 23 +++++++++++++++++++++-- 1 file changed, 21 insertions(+), 2 deletions(-) --- a/drivers/net/wireless/iwlwifi/iwl-trans-pcie-rx.c +++ b/drivers/net/wireless/iwlwifi/iwl-trans-pcie-rx.c @@ -315,6 +315,14 @@ static void iwlagn_rx_allocate(struct iw rxb->page_dma = dma_map_page(trans->dev, page, 0, PAGE_SIZE << hw_params(trans).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, hw_params(trans).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! */ @@ -450,8 +458,19 @@ static void iwl_rx_handle_rxbuf(struct i dma_map_page(trans->dev, rxb->page, 0, PAGE_SIZE << hw_params(trans).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, hw_params(trans).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);