spider_net_prepare_rx_descr(struct spider_net_card *card,
                            struct spider_net_descr *descr)
 {
+       dma_addr_t buf;
        int error = 0;
        int offset;
        int bufsize;
        if (offset)
                skb_reserve(descr->skb, SPIDER_NET_RXBUF_ALIGN - offset);
        /* io-mmu-map the skb */
-       descr->buf_addr = pci_map_single(card->pdev, descr->skb->data,
+       buf = pci_map_single(card->pdev, descr->skb->data,
                                         SPIDER_NET_MAX_MTU,
                                         PCI_DMA_BIDIRECTIONAL);
-       if (descr->buf_addr == DMA_ERROR_CODE) {
+       descr->buf_addr = buf;
+       if (buf == DMA_ERROR_CODE) {
                dev_kfree_skb_any(descr->skb);
                if (netif_msg_rx_err(card))
                        pr_err("Could not iommu-map rx buffer\n");
                            struct spider_net_descr *descr,
                            struct sk_buff *skb)
 {
-       descr->buf_addr = pci_map_single(card->pdev, skb->data,
-                                        skb->len, PCI_DMA_BIDIRECTIONAL);
-       if (descr->buf_addr == DMA_ERROR_CODE) {
+       dma_addr_t buf = pci_map_single(card->pdev, skb->data,
+                                       skb->len, PCI_DMA_BIDIRECTIONAL);
+       if (buf == DMA_ERROR_CODE) {
                if (netif_msg_tx_err(card))
                        pr_err("could not iommu-map packet (%p, %i). "
                                  "Dropping packet\n", skb->data, skb->len);
                return -ENOMEM;
        }
 
+       descr->buf_addr = buf;
        descr->buf_size = skb->len;
        descr->skb = skb;
        descr->data_status = 0;