Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751182AbWIXP13 (ORCPT ); Sun, 24 Sep 2006 11:27:29 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1751179AbWIXP13 (ORCPT ); Sun, 24 Sep 2006 11:27:29 -0400 Received: from relay.2ka.mipt.ru ([194.85.82.65]:21464 "EHLO 2ka.mipt.ru") by vger.kernel.org with ESMTP id S1751177AbWIXP12 (ORCPT ); Sun, 24 Sep 2006 11:27:28 -0400 Date: Sun, 24 Sep 2006 19:26:51 +0400 From: Evgeniy Polyakov To: Andrew Morton Cc: David Miller , auke-jan.h.kok@intel.com, Holger.Kiehl@dwd.de, linux-kernel@vger.kernel.org, linux-net@vger.kernel.org, netdev@vger.kernel.org, john.ronciak@intel.com Subject: Re: 2.6.1[78] page allocation failure. order:3, mode:0x20 Message-ID: <20060924152651.GA2077@2ka.mipt.ru> References: <20060922004253.2e2e2612.akpm@osdl.org> <4514190C.8010901@intel.com> <20060922215000.c1fde093.akpm@osdl.org> <20060922.222507.74751476.davem@davemloft.net> <20060922223348.1b24fda5.akpm@osdl.org> Mime-Version: 1.0 Content-Type: text/plain; charset=koi8-r Content-Disposition: inline In-Reply-To: <20060922223348.1b24fda5.akpm@osdl.org> User-Agent: Mutt/1.5.9i X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-1.7.5 (2ka.mipt.ru [0.0.0.0]); Sun, 24 Sep 2006 19:26:53 +0400 (MSD) Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 3862 Lines: 89 On Fri, Sep 22, 2006 at 10:33:48PM -0700, Andrew Morton (akpm@osdl.org) wrote: > > The NET_IP_ALIGN existed not just for fun :) There are ramifications > > for removing it. > > It's still there, isn't it? > > For the 9k MTU case, for example, we end up allocating 16384 byte skbs > instead of 32786 kbytes ones. This patch will not help - netdev_alloc_skb() adds additional NET_SKB_PAD and then alloc_skb() adds sizeof(struct skb_shared_info). And even if you acconut for them in adapter->rx_buf_len, chip still can overwrite that area (in the thread mentioned in this e-mail thread before I posted such patch and received a dump of sizes chip receives - there were a lot of _different_ ones which were too close to the limit). > > diff -puN drivers/net/e1000/e1000_main.c~e1000-account-for-net_ip_align-when-calculating-bufsiz drivers/net/e1000/e1000_main.c > --- a/drivers/net/e1000/e1000_main.c~e1000-account-for-net_ip_align-when-calculating-bufsiz > +++ a/drivers/net/e1000/e1000_main.c > @@ -1101,7 +1101,7 @@ e1000_sw_init(struct e1000_adapter *adap > > pci_read_config_word(pdev, PCI_COMMAND, &hw->pci_cmd_word); > > - adapter->rx_buffer_len = MAXIMUM_ETHERNET_VLAN_SIZE; > + adapter->rx_buffer_len = MAXIMUM_ETHERNET_VLAN_SIZE + NET_IP_ALIGN; > adapter->rx_ps_bsize0 = E1000_RXBUFFER_128; > hw->max_frame_size = netdev->mtu + > ENET_HEADER_SIZE + ETHERNET_FCS_SIZE; > @@ -3163,26 +3163,27 @@ e1000_change_mtu(struct net_device *netd > * larger slab size > * i.e. RXBUFFER_2048 --> size-4096 slab */ > > - if (max_frame <= E1000_RXBUFFER_256) > + if (max_frame + NET_IP_ALIGN <= E1000_RXBUFFER_256) > adapter->rx_buffer_len = E1000_RXBUFFER_256; > - else if (max_frame <= E1000_RXBUFFER_512) > + else if (max_frame + NET_IP_ALIGN <= E1000_RXBUFFER_512) > adapter->rx_buffer_len = E1000_RXBUFFER_512; > - else if (max_frame <= E1000_RXBUFFER_1024) > + else if (max_frame + NET_IP_ALIGN <= E1000_RXBUFFER_1024) > adapter->rx_buffer_len = E1000_RXBUFFER_1024; > - else if (max_frame <= E1000_RXBUFFER_2048) > + else if (max_frame + NET_IP_ALIGN <= E1000_RXBUFFER_2048) > adapter->rx_buffer_len = E1000_RXBUFFER_2048; > - else if (max_frame <= E1000_RXBUFFER_4096) > + else if (max_frame + NET_IP_ALIGN <= E1000_RXBUFFER_4096) > adapter->rx_buffer_len = E1000_RXBUFFER_4096; > - else if (max_frame <= E1000_RXBUFFER_8192) > + else if (max_frame + NET_IP_ALIGN <= E1000_RXBUFFER_8192) > adapter->rx_buffer_len = E1000_RXBUFFER_8192; > - else if (max_frame <= E1000_RXBUFFER_16384) > + else > adapter->rx_buffer_len = E1000_RXBUFFER_16384; > > /* adjust allocation if LPE protects us, and we aren't using SBP */ > if (!adapter->hw.tbi_compatibility_on && > ((max_frame == MAXIMUM_ETHERNET_FRAME_SIZE) || > (max_frame == MAXIMUM_ETHERNET_VLAN_SIZE))) > - adapter->rx_buffer_len = MAXIMUM_ETHERNET_VLAN_SIZE; > + adapter->rx_buffer_len = MAXIMUM_ETHERNET_VLAN_SIZE + > + NET_IP_ALIGN; > > netdev->mtu = new_mtu; > > @@ -4002,7 +4003,8 @@ e1000_alloc_rx_buffers(struct e1000_adap > struct e1000_buffer *buffer_info; > struct sk_buff *skb; > unsigned int i; > - unsigned int bufsz = adapter->rx_buffer_len + NET_IP_ALIGN; > + /* we have already accounted for NET_IP_ALIGN */ > + unsigned int bufsz = adapter->rx_buffer_len; > > i = rx_ring->next_to_use; > buffer_info = &rx_ring->buffer_info[i]; > _ > > - > To unsubscribe from this list: send the line "unsubscribe netdev" in > the body of a message to majordomo@vger.kernel.org > More majordomo info at http://vger.kernel.org/majordomo-info.html -- Evgeniy Polyakov - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/