From mboxrd@z Thu Jan 1 00:00:00 1970 From: Eric Dumazet Subject: Re: PROBLEM: Silent data corruption when using sendfile() Date: Sat, 14 Jul 2012 12:33:24 +0200 Message-ID: <1342262004.3265.9279.camel@edumazet-glaptop> References: <20120713171835.GA26052@vault.local> <1342254042.3265.9017.camel@edumazet-glaptop> <20120714083136.GO16256@1wt.eu> <20120714101321.GA26329@vault.local> Mime-Version: 1.0 Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: 7bit Cc: Willy Tarreau , Hillf Danton , linux-kernel@vger.kernel.org, Linux-Netdev To: Johannes Truschnigg Return-path: In-Reply-To: <20120714101321.GA26329@vault.local> Sender: linux-kernel-owner@vger.kernel.org List-Id: netdev.vger.kernel.org On Sat, 2012-07-14 at 12:13 +0200, Johannes Truschnigg wrote: > On Sat, Jul 14, 2012 at 10:31:36AM +0200, Willy Tarreau wrote: > > > Please Johannes could you try latest kernel tree ? > > > > It would be useful, especially given the amount of changes you performed > > in this area in latest version, it could be very possible that this new > > bug got fixed as a side effect ! > > I upgraded to 3.4.4 (identical config as the 3.4.0 build I've been running) > and what can I say - the problem really seems to have disappeared. I performed > about 3700 iterations of my previos tests over the night, and the data always > turned out to be OK, not a single byte turned out kaput! > > I wish I would have tested that earlier, and spared you the noise... well, > maybe someone who runs into a similar problem in the future will have this > discovery save her/him some time and headaches and make her/him just upgrade > kernels :) > > Thanks a lot for your polite and quick responses! > Nice to hear. Now we should make sure we have all needed fixes for prior stable kernels as well ! Still trying to understand the issue, since I thought I only did optimizations, not bug fixes. So maybe real bug is still there but its probability of occurrence lowered enough to not hit your workload. Hmmm...