In https://bugzilla.kernel.org/show_bug.cgi?id=42976, a system with driver rtl8192se used as an AP suffers from "Out of SW-IOMMU space" errors. These are caused by the DMA buffers used for beacons never being unmapped. This bug was also reported at https://bugs.launchpad.net/ubuntu/+source/linux/+bug/961618 Reported-and-Tested-by: Da Xue <da@xxxxxxxxxxxxxxxx> Signed-off-by: Larry Finger <Larry.Finger@xxxxxxxxxxxx> Cc: Stable <stable@xxxxxxxxxxxxxxx> --- John, This is not a regression. The problem has been in the driver from the beginning. It has not been found earlier due to the infrequent use of these devices in access points. I think it can be applied to 3.5. Larry --- Index: wireless-testing-new/drivers/net/wireless/rtlwifi/pci.c =================================================================== --- wireless-testing-new.orig/drivers/net/wireless/rtlwifi/pci.c +++ wireless-testing-new/drivers/net/wireless/rtlwifi/pci.c @@ -912,8 +912,13 @@ static void _rtl_pci_prepare_bcn_tasklet memset(&tcb_desc, 0, sizeof(struct rtl_tcb_desc)); ring = &rtlpci->tx_ring[BEACON_QUEUE]; pskb = __skb_dequeue(&ring->queue); - if (pskb) + if (pskb) { + struct rtl_tx_desc *entry = &ring->desc[ring->idx]; + pci_unmap_single(rtlpci->pdev, rtlpriv->cfg->ops->get_desc( + (u8 *) entry, true, HW_DESC_TXBUFF_ADDR), + pskb->len, PCI_DMA_TODEVICE); kfree_skb(pskb); + } /*NB: the beacon data buffer must be 32-bit aligned. */ pskb = ieee80211_beacon_get(hw, mac->vif); -- To unsubscribe from this list: send the line "unsubscribe linux-wireless" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
