From mboxrd@z Thu Jan 1 00:00:00 1970 From: Matt Mackall Subject: Re: 2.6.23 WARNING: at kernel/softirq.c:139 local_bh_enable() Date: Fri, 23 Nov 2007 13:11:20 -0600 Message-ID: <20071123191120.GA19691@waste.org> References: <4745DCD7.8070805@simon.arlott.org.uk> <20071123002157.cb27f4a1.akpm@linux-foundation.org> <20071123105518.GA22062@2ka.mipt.ru> <20071123170756.GV19691@waste.org> <20071123175757.GA23991@2ka.mipt.ru> <20071123184851.GA14415@2ka.mipt.ru> <20071123185101.GA17582@2ka.mipt.ru> <20071123185906.GA23710@2ka.mipt.ru> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Cc: Andrew Morton , Simon Arlott , Linux Kernel Mailing List , netdev@vger.kernel.org, Ingo Molnar To: Evgeniy Polyakov Return-path: Received: from waste.org ([66.93.16.53]:50241 "EHLO waste.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755267AbXKWTQ2 (ORCPT ); Fri, 23 Nov 2007 14:16:28 -0500 Content-Disposition: inline In-Reply-To: <20071123185906.GA23710@2ka.mipt.ru> Sender: netdev-owner@vger.kernel.org List-Id: netdev.vger.kernel.org On Fri, Nov 23, 2007 at 09:59:06PM +0300, Evgeniy Polyakov wrote: > On Fri, Nov 23, 2007 at 09:51:01PM +0300, Evgeniy Polyakov (johnpol@2ka.mipt.ru) wrote: > > On Fri, Nov 23, 2007 at 09:48:51PM +0300, Evgeniy Polyakov (johnpol@2ka.mipt.ru) wrote: > > > Stop, we are trying to free skb without destructor and catch connection > > > tracking, so it is not a solution. To fix the problem we need to check > > > if it is not netfilter related, kind of this (not tested), Simon please > > > give it a try: > > > > And to be really cool we need to bypass skbs with xfrm attached, since > > its freeing also assumes BH context. > > What about compile options? What about my original suggestion that we mark skbs owned by netpoll and free only those. Much safer, no? Untested: diff -r c60016ba6237 net/core/netpoll.c --- a/net/core/netpoll.c Tue Nov 13 09:09:36 2007 -0800 +++ b/net/core/netpoll.c Fri Nov 23 13:10:28 2007 -0600 @@ -203,6 +203,12 @@ static void refill_skbs(void) spin_unlock_irqrestore(&skb_pool.lock, flags); } +/* used to mark an skb as owned by netpoll */ +static void netpoll_skb_destroy(struct sk_buff *skb) +{ + return; +} + static void zap_completion_queue(void) { unsigned long flags; @@ -219,10 +225,12 @@ static void zap_completion_queue(void) while (clist != NULL) { struct sk_buff *skb = clist; clist = clist->next; - if (skb->destructor) + if (skb->destructor == netpoll_skb_destroy) { + skb->destructor = NULL; + __kfree_skb(skb); + } + else dev_kfree_skb_any(skb); /* put this one back */ - else - __kfree_skb(skb); } } @@ -252,6 +260,7 @@ repeat: atomic_set(&skb->users, 1); skb_reserve(skb, reserve); + skb->destructor = netpoll_skb_destroy; return skb; } -- Mathematics is the supreme nostalgia of our time.