From mboxrd@z Thu Jan 1 00:00:00 1970 Received: with ECARTIS (v1.0.0; list linux-mips); Wed, 13 Nov 2002 21:47:03 +0100 (CET) Received: from mx2.mips.com ([206.31.31.227]:11456 "EHLO mx2.mips.com") by linux-mips.org with ESMTP id ; Wed, 13 Nov 2002 21:47:02 +0100 Received: from newman.mips.com (ns-dmz [206.31.31.225]) by mx2.mips.com (8.12.5/8.12.5) with ESMTP id gADKkoNf012858; Wed, 13 Nov 2002 12:46:51 -0800 (PST) Received: from copfs01.mips.com (copfs01 [192.168.205.101]) by newman.mips.com (8.9.3/8.9.0) with ESMTP id MAA14450; Wed, 13 Nov 2002 12:46:50 -0800 (PST) Received: from mips.com (copsun17 [192.168.205.27]) by copfs01.mips.com (8.11.4/8.9.0) with ESMTP id gADKkob22973; Wed, 13 Nov 2002 21:46:50 +0100 (MET) Message-ID: <3DD2BA39.E1457D67@mips.com> Date: Wed, 13 Nov 2002 21:46:50 +0100 From: Carsten Langgaard X-Mailer: Mozilla 4.77 [en] (X11; U; SunOS 5.8 sun4u) X-Accept-Language: en MIME-Version: 1.0 To: Jeff Garzik CC: Ralf Baechle , linux-mips@linux-mips.org, tsbogend@alpha.franken.de, linux-net@vger.kernel.org, kevink@mips.com Subject: Re: BUG in the PCNET32 ethernet driver References: <3DD254F8.14DE20EA@mips.com> <3DD280FB.7070907@pobox.com> <3DD2B128.62DFB392@mips.com> <3DD2B402.8040508@pobox.com> Content-Type: multipart/mixed; boundary="------------F6D4B5191D51956889E84897" Return-Path: X-Envelope-To: <"|/home/ecartis/ecartis -s linux-mips"> (uid 0) X-Orcpt: rfc822;linux-mips@linux-mips.org Original-Recipient: rfc822;linux-mips@linux-mips.org X-archive-position: 634 X-ecartis-version: Ecartis v1.0.0 Sender: linux-mips-bounce@linux-mips.org Errors-to: linux-mips-bounce@linux-mips.org X-original-sender: carstenl@mips.com Precedence: bulk X-list: linux-mips This is a multi-part message in MIME format. --------------F6D4B5191D51956889E84897 Content-Type: text/plain; charset=iso-8859-15 Content-Transfer-Encoding: 7bit Jeff Garzik wrote: > Carsten Langgaard wrote: > > > Jeff Garzik wrote: > > > > > > >Carsten Langgaard wrote: > > > > > > > > >>@@ -1316,13 +1316,13 @@ > > >> if ((newskb = dev_alloc_skb (PKT_BUF_SZ))) { > > >> skb_reserve (newskb, 2); > > >> skb = lp->rx_skbuff[entry]; > > >>- pci_unmap_single(lp->pci_dev, > > lp->rx_dma_addr[entry], skb->len, > > >>PCI_DMA_FROMDEVICE); > > >>+ pci_unmap_single(lp->pci_dev, > > lp->rx_dma_addr[entry], pkt_len +2, > > >>PCI_DMA_FROMDEVICE); > > >> skb_put (skb, pkt_len); > > >> lp->rx_skbuff[entry] = newskb; > > > > > >Why does this line not reference PKT_BUF_SZ when all the others do? > > > > > > In this case we know the size of the packet and therefore only need to > > handle that. > > In the other cases we don't know have big the receiving packet is > > going to be, so we has to > > take care of the whole buffer. > > Well, it's a seriously bad idea to pass different values to map and > unmap steps, because on some platforms you could wind up telling the > IOMMU or some other allocator that you are allocating N bytes, but > freeing N-M bytes. IOW, a leak. Ok, fine. There is actually another place in the code that also need a fix then. > > Now that that's been clarified, please fix up the patch and resubmit... > with this issue fixed, it looks apply-able. > I have made the change and attached a new patch. > > Jeff -- _ _ ____ ___ Carsten Langgaard Mailto:carstenl@mips.com |\ /|||___)(___ MIPS Denmark Direct: +45 4486 5527 | \/ ||| ____) Lautrupvang 4B Switch: +45 4486 5555 TECHNOLOGIES 2750 Ballerup Fax...: +45 4486 5556 Denmark http://www.mips.com --------------F6D4B5191D51956889E84897 Content-Type: text/plain; charset=iso-8859-15; name="pcnet32.2.patch" Content-Transfer-Encoding: 7bit Content-Disposition: inline; filename="pcnet32.2.patch" Index: drivers/net/pcnet32.c =================================================================== RCS file: /home/cvs/linux/drivers/net/pcnet32.c,v retrieving revision 1.33.2.3 diff -u -r1.33.2.3 pcnet32.c --- drivers/net/pcnet32.c 6 Oct 2002 20:49:43 -0000 1.33.2.3 +++ drivers/net/pcnet32.c 13 Nov 2002 20:38:39 -0000 @@ -981,7 +981,7 @@ } skb_reserve (rx_skbuff, 2); } - lp->rx_dma_addr[i] = pci_map_single(lp->pci_dev, rx_skbuff->tail, rx_skbuff->len, PCI_DMA_FROMDEVICE); + lp->rx_dma_addr[i] = pci_map_single(lp->pci_dev, rx_skbuff->tail, PKT_BUF_SZ, PCI_DMA_FROMDEVICE); lp->rx_ring[i].base = (u32)le32_to_cpu(lp->rx_dma_addr[i]); lp->rx_ring[i].buf_length = le16_to_cpu(-PKT_BUF_SZ); lp->rx_ring[i].status = le16_to_cpu(0x8000); @@ -1316,13 +1316,13 @@ if ((newskb = dev_alloc_skb (PKT_BUF_SZ))) { skb_reserve (newskb, 2); skb = lp->rx_skbuff[entry]; - pci_unmap_single(lp->pci_dev, lp->rx_dma_addr[entry], skb->len, PCI_DMA_FROMDEVICE); + pci_unmap_single(lp->pci_dev, lp->rx_dma_addr[entry], PKT_BUF_SZ, PCI_DMA_FROMDEVICE); skb_put (skb, pkt_len); lp->rx_skbuff[entry] = newskb; newskb->dev = dev; lp->rx_dma_addr[entry] = pci_map_single(lp->pci_dev, newskb->tail, - newskb->len, PCI_DMA_FROMDEVICE); + PKT_BUF_SZ, PCI_DMA_FROMDEVICE); lp->rx_ring[entry].base = le32_to_cpu(lp->rx_dma_addr[entry]); rx_in_place = 1; } else @@ -1349,13 +1349,10 @@ if (!rx_in_place) { skb_reserve(skb,2); /* 16 byte align */ skb_put(skb,pkt_len); /* Make room */ - pci_dma_sync_single(lp->pci_dev, - lp->rx_dma_addr[entry], - pkt_len, - PCI_DMA_FROMDEVICE); eth_copy_and_sum(skb, (unsigned char *)(lp->rx_skbuff[entry]->tail), pkt_len,0); + lp->rx_dma_addr[entry] = pci_map_single(lp->pci_dev, lp->rx_skbuff[entry]->tail, PKT_BUF_SZ, PCI_DMA_FROMDEVICE); } lp->stats.rx_bytes += skb->len; skb->protocol=eth_type_trans(skb,dev); @@ -1406,7 +1403,7 @@ for (i = 0; i < RX_RING_SIZE; i++) { lp->rx_ring[i].status = 0; if (lp->rx_skbuff[i]) { - pci_unmap_single(lp->pci_dev, lp->rx_dma_addr[i], lp->rx_skbuff[i]->len, PCI_DMA_FROMDEVICE); + pci_unmap_single(lp->pci_dev, lp->rx_dma_addr[i], PKT_BUF_SZ, PCI_DMA_FROMDEVICE); dev_kfree_skb(lp->rx_skbuff[i]); } lp->rx_skbuff[i] = NULL; --------------F6D4B5191D51956889E84897--