From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751326AbVKOFlW (ORCPT ); Tue, 15 Nov 2005 00:41:22 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1751331AbVKOFlW (ORCPT ); Tue, 15 Nov 2005 00:41:22 -0500 Received: from dsl027-180-168.sfo1.dsl.speakeasy.net ([216.27.180.168]:31980 "EHLO sunset.davemloft.net") by vger.kernel.org with ESMTP id S1751326AbVKOFlV (ORCPT ); Tue, 15 Nov 2005 00:41:21 -0500 Date: Mon, 14 Nov 2005 21:41:30 -0800 (PST) Message-Id: <20051114.214130.57199557.davem@davemloft.net> To: mpm@selenic.com Cc: jeffrey.t.kirsher@intel.com, linux-kernel@vger.kernel.org, netdev@vger.kernel.org Subject: Re: [BUG] netpoll is unable to handle skb's using packet split From: "David S. Miller" In-Reply-To: <20051114.213922.16377460.davem@davemloft.net> References: <9929d2390511141315t2fb15b2aucbbebcbe4cec7ef1@mail.gmail.com> <20051115052358.GG31287@waste.org> <20051114.213922.16377460.davem@davemloft.net> X-Mailer: Mew version 4.2.53 on Emacs 21.4 / Mule 5.0 (SAKAKI) Mime-Version: 1.0 Content-Type: Text/Plain; charset=us-ascii Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org From: "David S. Miller" Date: Mon, 14 Nov 2005 21:39:22 -0800 (PST) > From: Matt Mackall > Date: Mon, 14 Nov 2005 21:23:58 -0800 > > > What is "packet split" in this context? > > It's a mode of buffering used by the e1000 driver. BTW, the issue is that in packet split mode, the e1000 driver is feeding paged based non-linear SKBs into the stack on receive which is completely legal but aparently netpoll or something parsing netpoll RX packets does not handle it properly. That's why the reporter suggested that perhaps an skb_linearize() call could be added to fix the problem, but it is unknown whether that call can be made in the context in which it would be needed.