iwlwifi: handle DMA mapping failures
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").
Cc: stable@vger.kernel.org
Reported-by: Shuah Khan <shuah.khan@hp.com>
Reviewed-by: Emmanuel Grumbach <emmanuel.grumbach@intel.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
diff --git a/drivers/net/wireless/iwlwifi/pcie/rx.c b/drivers/net/wireless/iwlwifi/pcie/rx.c
index 17c8e5d..bb69f8f 100644
--- a/drivers/net/wireless/iwlwifi/pcie/rx.c
+++ b/drivers/net/wireless/iwlwifi/pcie/rx.c
@@ -321,6 +321,14 @@
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! */
@@ -488,8 +496,19 @@
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);