From mboxrd@z Thu Jan  1 00:00:00 1970
From: David Miller <davem@davemloft.net>
Subject: Re: [PATCH] net: fix race in process_backlog
Date: Wed, 03 Oct 2007 16:39:02 -0700 (PDT)
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From: Stephen Hemminger <shemminger@linux-foundation.org>
Date: Wed, 3 Oct 2007 15:05:19 -0700

> On Wed, 03 Oct 2007 14:58:07 -0700 (PDT)
> David Miller <davem@davemloft.net> wrote:
> 
> > From: Peter Zijlstra <a.p.zijlstra@chello.nl>
> > Date: Wed, 03 Oct 2007 17:44:53 +0200
> > 
> > > Index: linux-2.6/net/core/dev.c
> > > ===================================================================
> > > --- linux-2.6.orig/net/core/dev.c
> > > +++ linux-2.6/net/core/dev.c
> > > @@ -2095,11 +2095,11 @@ static int process_backlog(struct napi_s
> > >  
> > >  		local_irq_disable();
> > >  		skb = __skb_dequeue(&queue->input_pkt_queue);
> > > -		local_irq_enable();
> > >  		if (!skb) {
> > > -			napi_complete(napi);
> > > +			__napi_complete(napi);
> > >  			break;
> > >  		}
> > > +		local_irq_enable();
> > 
> > What re-enables interrupts in the !skb path?
> 
> This looks like a better fix. the irq_enable is needed in both cases.

Yep, applied, thanks Peter and Stephen.