From mboxrd@z Thu Jan 1 00:00:00 1970 Subject: Re: [RFC][PATCH 2/9] deadlock prevention core From: Peter Zijlstra In-Reply-To: <20060809161816.GA14627@postel.suug.ch> References: <20060808193345.1396.16773.sendpatchset@lappy> <20060808211731.GR14627@postel.suug.ch> <44D93BB3.5070507@google.com> <20060808.183920.41636471.davem@davemloft.net> <44D976E6.5010106@google.com> <20060809131942.GY14627@postel.suug.ch> <1155132440.12225.70.camel@twins> <20060809161816.GA14627@postel.suug.ch> Content-Type: text/plain Date: Wed, 09 Aug 2006 18:19:54 +0200 Message-Id: <1155140394.12225.88.camel@twins> Mime-Version: 1.0 Content-Transfer-Encoding: 7bit Sender: owner-linux-mm@kvack.org Return-Path: To: Thomas Graf Cc: Daniel Phillips , David Miller , linux-mm@kvack.org, linux-kernel@vger.kernel.org, netdev@vger.kernel.org List-ID: On Wed, 2006-08-09 at 18:18 +0200, Thomas Graf wrote: > * Peter Zijlstra 2006-08-09 16:07 > > I think Daniel was thinking of adding struct net_device * > > sk_buff::alloc_dev, > > I know I was after reading the first few mails. However if adding a > > field > > there is strict no-no.... > > > > /me takes a look at struct sk_buff > > > > Hmm, what does sk_buff::input_dev do? That seems to store the initial > > device? > > No, skb->input_dev is used when redirecting packets around in the > stack and may change. Even if it would keep its value the reference > to the netdevice is not valid anymore when you free the skb as the > skb was queued and the refcnt acquired in __netifx_rx_schedule() > has been released again thus making it possible for the netdevice > to disappear. Bah, tricky stuff that. disregards this part from -v2 then :-( -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@kvack.org. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: email@kvack.org