From mboxrd@z Thu Jan 1 00:00:00 1970 From: Jarek Poplawski Subject: Re: [patch 04/13] ppp_generic: fix lockdep warning Date: Mon, 14 May 2007 09:28:45 +0200 Message-ID: <20070514072845.GA2081@ff.dom.local> References: <20070511.140309.59656886.davem@davemloft.net> <20070511141225.cf7a6909.akpm@linux-foundation.org> <20070514060700.GA1000@ff.dom.local> <20070513.233937.99203647.davem@davemloft.net> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Cc: akpm@linux-foundation.org, jeff@garzik.org, netdev@vger.kernel.org, jura@netams.com, paulus@samba.org To: David Miller Return-path: Received: from mx10.go2.pl ([193.17.41.74]:54711 "EHLO poczta.o2.pl" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1752820AbXENHWN (ORCPT ); Mon, 14 May 2007 03:22:13 -0400 Content-Disposition: inline In-Reply-To: <20070513.233937.99203647.davem@davemloft.net> Sender: netdev-owner@vger.kernel.org List-Id: netdev.vger.kernel.org On Sun, May 13, 2007 at 11:39:37PM -0700, David Miller wrote: > From: Jarek Poplawski > Date: Mon, 14 May 2007 08:07:00 +0200 > > > After sending this patch I was a little confused, when next > > lockdep warning report appeared, and I thought - since this is > > not enough, this patch could be dumped. But now I changed my > > mind: there are really many possibilities of strange connections > > between locks taken from vlans, ppp (with pppoe), multicasts etc. > > - that every one possibility less is a gain here. > ... > > Of course, later, if somebody will find better solution, they could > > be removed, > > I already suggested a better fix, you ignored it. No, I couldn't have ignored any of your suggestions (I would've written about any doubts, anyway). I simply misunderstood! I thought you mean different classes for netdevs used in vlan, and I prepared such a patch... Sorry! > > For each unique netdev type, use a different locking class. > > That will fix this forever, anything else is a situation specific > band-aid (but then again isn't that what every lockdep annotation is > :-). Yes, this is very good idea, and I wonder, why you didn't try this yourself (after my "ignore"). I thought a little about this, but was afraid of it's wide range. Some things - like in vlans - should be removed then, for this to work. I'll try to send something like this soon (but I'm not so optimistic it will cure all or forever...). Regards, Jarek P.