From mboxrd@z Thu Jan 1 00:00:00 1970 From: Dave Jones Subject: Re: net_dma: mark broken Date: Mon, 23 Dec 2013 11:21:13 -0500 Message-ID: <20131223162113.GA20363@redhat.com> References: <20131220211228.BC817660C74@gitolite.kernel.org> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Cc: Dan Williams To: netdev@vger.kernel.org Return-path: Received: from mx1.redhat.com ([209.132.183.28]:62670 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1757794Ab3LWQVV (ORCPT ); Mon, 23 Dec 2013 11:21:21 -0500 Content-Disposition: inline In-Reply-To: <20131220211228.BC817660C74@gitolite.kernel.org> Sender: netdev-owner@vger.kernel.org List-ID: On Fri, Dec 20, 2013 at 09:12:28PM +0000, Linux Kernel wrote: > Gitweb: http://git.kernel.org/linus/;a=commit;h=77873803363c9e831fc1d1e6895c084279090c22 > Commit: 77873803363c9e831fc1d1e6895c084279090c22 > Parent: 0baf8f6a2ac86c2c40ed0cacab8ea3d17371a1bb > Author: Dan Williams > AuthorDate: Tue Dec 17 10:09:32 2013 -0800 > Committer: Dan Williams > CommitDate: Wed Dec 18 12:53:43 2013 -0800 > > net_dma: mark broken > > net_dma can cause data to be copied to a stale mapping if a > copy-on-write fault occurs during dma. The application sees missing > data. Since this commit, coverity picked up a possible logic contradiction in tcp_rcv_established Now that the only thing setting copied_early = 1 is inside an ifdef that won't be set, it notes that this code is unreachable.. 5271 if (!copied_early || tp->rcv_nxt != tp->rcv_wup) 5272 __tcp_ack_snd_check(sk, 0); I don't understand all the subtleties of that huge function, so another set of eyes would be appreciated. If it's a non-issue, I'll flag it as such for coverity so it doesn't get picked up again. Dave