From mboxrd@z Thu Jan 1 00:00:00 1970 From: Ingo Molnar Subject: Re: [PATCH tip/core/rcu 05/13] net: add checking to rcu_dereference() primitives Date: Sun, 14 Feb 2010 09:23:14 +0100 Message-ID: <20100214082314.GA12658@elte.hu> References: <20100212000016.GA25781@linux.vnet.ibm.com> <1265932839-25899-5-git-send-email-paulmck@linux.vnet.ibm.com> <1265948152.2891.25.camel@edumazet-laptop> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Cc: "Paul E. McKenney" , linux-kernel@vger.kernel.org, laijs@cn.fujitsu.com, dipankar@in.ibm.com, akpm@linux-foundation.org, mathieu.desnoyers@polymtl.ca, josh@joshtriplett.org, dvhltc@us.ibm.com, niv@us.ibm.com, tglx@linutronix.de, peterz@infradead.org, rostedt@goodmis.org, Valdis.Kletnieks@vt.edu, dhowells@redhat.com, David Miller , netdev To: Eric Dumazet Return-path: Received: from mx3.mail.elte.hu ([157.181.1.138]:51184 "EHLO mx3.mail.elte.hu" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752977Ab0BNIYG (ORCPT ); Sun, 14 Feb 2010 03:24:06 -0500 Content-Disposition: inline In-Reply-To: <1265948152.2891.25.camel@edumazet-laptop> Sender: netdev-owner@vger.kernel.org List-ID: * Eric Dumazet wrote: > Le jeudi 11 f??vrier 2010 ?? 16:00 -0800, Paul E. McKenney a ??crit : > > Update rcu_dereference() primitives to use new lockdep-based checking. > > The rcu_dereference() in __in6_dev_get() may be protected either by > > rcu_read_lock() or RTNL, per Eric Dumazet. The rcu_dereference() > > in __sk_free() is protected by the fact that it is never reached if an > > update could change it. Check for this by using rcu_dereference_check() > > to verify that the struct sock's ->sk_wmem_alloc counter is zero. > > > > Signed-off-by: Paul E. McKenney > > CC to netdev and David Miller, network maintainer. > > Acked-by: Eric Dumazet > > Thanks Paul, great work ! Dave, does this look good to you too? Cannot pick up the rest of the patchset without these checks/annotations into the RCU tree as there's too many warnings triggering in the networking code. So it's an all-or-nothing patchset in that regard. Thanks, Ingo