From mboxrd@z Thu Jan 1 00:00:00 1970 From: Chuck Lever Subject: Re: nfs + Reiser4 Date: Wed, 07 Apr 2010 14:59:36 -0400 Message-ID: <4BBCD618.50301@oracle.com> References: <20100407173438.GA25614@fieldses.org> <4BBCD271.5040100@oracle.com> <20100407185157.GF26072@fieldses.org> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Cc: nfs@lists.sourceforge.net, gg-B3jsHfKwJfLR7s880joybQ@public.gmane.org To: "J. Bruce Fields" Return-path: Received: from neil.brown.name ([220.233.11.133]:54956 "EHLO neil.brown.name" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1758200Ab0DGTAf (ORCPT ); Wed, 7 Apr 2010 15:00:35 -0400 Received: from brown by neil.brown.name with local (Exim 4.71) (envelope-from ) id 1NzaUL-0001nt-TE for linux-nfs@vger.kernel.org; Thu, 08 Apr 2010 05:00:33 +1000 In-Reply-To: <20100407185157.GF26072@fieldses.org> Sender: linux-nfs-owner@vger.kernel.org List-ID: On 04/07/2010 02:51 PM, J. Bruce Fields wrote: > On Wed, Apr 07, 2010 at 02:44:01PM -0400, Chuck Lever wrote: >> On 04/07/2010 01:34 PM, J. Bruce Fields wrote: >>> On Tue, Apr 06, 2010 at 07:52:21PM +0200, gg-B3jsHfKwJfLR7s880joybQ@public.gmane.org wrote: >>>> I am having serious headaches using nfs between a reiser4 server and arm >>>> client. >>>> Both on 2.6.29 vintage kernels. >>>> >>>> Files are constantly getting out of sync. >>>> >>>> Example : >>>> >>>> boot ARM via nfs >>>> edit lighttpd.conf on ARM >>>> check edit is visible on server. OK >>>> >>>> reboot ARM >>>> check file : reverted to an earlier state. >>>> check server: edited version still showing. >>> >>> So, on a freshly booted NFS client, you're opening and reading a file >>> and seeing file data that isn't even on the NFS server any more? >>> >>> That's beyond bizarre. Do you have a reliable way to reproduce the >>> problem? >> >> Could be XID replay. > > I'm not following you. You're thinking of a read request after the > reboot that unluckily reuses an old XID and gets stale data from the > servers reply cache? Or something else? Nothing unlucky about it. Just after a boot, if the client implementation isn't careful about choosing an initial XID, (eg it always starts with a psuedorandom number but uses the same seed every time), it will hit the server's replay cache. This can be quite reproducible for NFSROOT and a quiescent server. -- chuck[dot]lever[at]oracle[dot]com ------------------------------------------------------------------------------ Download Intel® Parallel Studio Eval Try the new software tools for yourself. Speed compiling, find bugs proactively, and fine-tune applications for parallel performance. See why Intel Parallel Studio got high marks during beta. http://p.sf.net/sfu/intel-sw-dev _______________________________________________ NFS maillist - NFS@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/nfs _______________________________________________ Please note that nfs@lists.sourceforge.net is being discontinued. Please subscribe to linux-nfs@vger.kernel.org instead. http://vger.kernel.org/vger-lists.html#linux-nfs