From mboxrd@z Thu Jan 1 00:00:00 1970 From: Jamal Hadi Salim Subject: Re: [patch net-next 3/6] net_sched: cls_bpf: remove faulty use of list_for_each_entry_rcu Date: Wed, 03 Dec 2014 09:37:46 -0500 Message-ID: <547F203A.3080208@mojatatu.com> References: <1417539636-12710-1-git-send-email-jiri@resnulli.us> <1417539636-12710-4-git-send-email-jiri@resnulli.us> <547F0743.4040301@mojatatu.com> <20141203132635.GH1860@nanopsycho.orion> Mime-Version: 1.0 Content-Type: text/plain; charset=windows-1252; format=flowed Content-Transfer-Encoding: 7bit Cc: netdev@vger.kernel.org, davem@davemloft.net To: Jiri Pirko Return-path: Received: from mail-ig0-f177.google.com ([209.85.213.177]:44463 "EHLO mail-ig0-f177.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752409AbaLCOhs (ORCPT ); Wed, 3 Dec 2014 09:37:48 -0500 Received: by mail-ig0-f177.google.com with SMTP id z20so12790300igj.4 for ; Wed, 03 Dec 2014 06:37:48 -0800 (PST) In-Reply-To: <20141203132635.GH1860@nanopsycho.orion> Sender: netdev-owner@vger.kernel.org List-ID: On 12/03/14 08:26, Jiri Pirko wrote: > Wed, Dec 03, 2014 at 01:51:15PM CET, jhs@mojatatu.com wrote: >> I think this may be problematic. Doesnt a flush operation also use the >> walker? > > I don't believe so. Just look at tc_dump_tfilter. > Actually we cant flush filters (we could actions). > But even if that would the the case, _rcu variant is wrong (yep, it > would have to be replaced by _safe variant then). > Sorry, still humping on the get part: that gets invoked for del for a filter that may be in use in the datapath. del uses rcu - should get not use rcu in such a case? cheers, jamal