From mboxrd@z Thu Jan 1 00:00:00 1970 From: Simon Horman Subject: Re: [PATCH] ipvs: fix dst_lock locking on dest update Date: Wed, 23 Feb 2011 09:26:24 +0900 Message-ID: <20110223002622.GI22597@verge.net.au> References: Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Cc: "David S. Miller" , netdev@vger.kernel.org, lvs-devel@vger.kernel.org To: Julian Anastasov Return-path: Content-Disposition: inline In-Reply-To: Sender: lvs-devel-owner@vger.kernel.org List-Id: netdev.vger.kernel.org On Tue, Feb 22, 2011 at 10:40:25AM +0200, Julian Anastasov wrote: > > Fix dst_lock usage in __ip_vs_update_dest. We need > _bh locking because destination is updated in user context. > Can cause lockups on frequent destination updates. > Problem reported by Simon Kirby. Bug was introduced > in 2.6.37 from the "ipvs: changes for local real server" > change. > > Signed-off-by: Julian Anastasov Acked-by: Simon Horman > --- > > Dave, please apply to net-2.6. > Patch is for 2.6.37+ and applies to 2.6.38-rc6. There is > little fuzz when applying to net-next, let me know if > I should provide patch for other trees. > > --- linux-2.6.37/net/netfilter/ipvs/ip_vs_ctl.c 2011-01-06 00:01:23.600069161 +0200 > +++ linux/net/netfilter/ipvs/ip_vs_ctl.c 2011-02-19 23:14:44.463250743 +0200 > @@ -810,9 +810,9 @@ __ip_vs_update_dest(struct ip_vs_service > dest->u_threshold = udest->u_threshold; > dest->l_threshold = udest->l_threshold; > > - spin_lock(&dest->dst_lock); > + spin_lock_bh(&dest->dst_lock); > ip_vs_dst_reset(dest); > - spin_unlock(&dest->dst_lock); > + spin_unlock_bh(&dest->dst_lock); > > if (add) > ip_vs_new_estimator(&dest->stats); >