From mboxrd@z Thu Jan 1 00:00:00 1970 From: Stephen Hemminger Subject: Re: [0/8] netpoll/bridge fixes Date: Thu, 10 Jun 2010 07:49:12 -0700 Message-ID: <20100610074912.1303e3da@nehalam> References: <20100610124047.GA16658@gondor.apana.org.au> Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Cc: "Michael S. Tsirkin" , Qianfeng Zhang , "David S. Miller" , netdev@vger.kernel.org, WANG Cong , Matt Mackall To: Herbert Xu Return-path: Received: from mail.vyatta.com ([76.74.103.46]:56045 "EHLO mail.vyatta.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753773Ab0FJOtT (ORCPT ); Thu, 10 Jun 2010 10:49:19 -0400 In-Reply-To: <20100610124047.GA16658@gondor.apana.org.au> Sender: netdev-owner@vger.kernel.org List-ID: On Thu, 10 Jun 2010 22:40:47 +1000 Herbert Xu wrote: > Hi: > > Qianfeng Zhang reported that he was seeing crashes with the > attached backtrace. > > I tracked this down to the recently added netpoll support in > the bridge device. It's a classic use-after-free problem. > > Trying to solve it brought out a host of other issues, some of > which existed prior to the new bridge code. The following patches > attempt to address some of these issues. > > Warning, this is completely untested (apart from compiling with > everything enabled) so please look but don't merge :) Thanks for looking at this, and yes the original code does look buggy. Not sure if I like the use of in_irq() to handle the netpoll packets as special case. Is in_irq() really reliable for this?