From mboxrd@z Thu Jan 1 00:00:00 1970 From: David Miller Subject: Re: [RFC][PATCH 2/9] deadlock prevention core Date: Tue, 08 Aug 2006 18:39:20 -0700 (PDT) Message-ID: <20060808.183920.41636471.davem@davemloft.net> References: <20060808193345.1396.16773.sendpatchset@lappy> <20060808211731.GR14627@postel.suug.ch> <44D93BB3.5070507@google.com> Mime-Version: 1.0 Content-Type: Text/Plain; charset=us-ascii Content-Transfer-Encoding: 7bit Cc: tgraf@suug.ch, a.p.zijlstra@chello.nl, linux-mm@kvack.org, linux-kernel@vger.kernel.org, netdev@vger.kernel.org Return-path: Received: from dsl027-180-168.sfo1.dsl.speakeasy.net ([216.27.180.168]:12262 "EHLO sunset.davemloft.net") by vger.kernel.org with ESMTP id S1030404AbWHIBjy (ORCPT ); Tue, 8 Aug 2006 21:39:54 -0400 To: phillips@google.com In-Reply-To: <44D93BB3.5070507@google.com> Sender: netdev-owner@vger.kernel.org List-Id: netdev.vger.kernel.org From: Daniel Phillips Date: Tue, 08 Aug 2006 18:34:43 -0700 > Can you please characterize the conditions under which skb->dev changes > after the alloc? Are there writings on this subtlety? The packet scheduler and classifier can redirect packets to different devices, and can the netfilter layer. The setting of skb->dev is wholly transient and you cannot rely upon it to be the same as when you set it on allocation. Even simple things like the bonding device change skb->dev on every receive. I think you need to study the networking stack a little more before you continue to play in this delicate area :-)