From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932343AbWG3QMf (ORCPT ); Sun, 30 Jul 2006 12:12:35 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S932349AbWG3QMf (ORCPT ); Sun, 30 Jul 2006 12:12:35 -0400 Received: from pat.uio.no ([129.240.10.4]:56784 "EHLO pat.uio.no") by vger.kernel.org with ESMTP id S932343AbWG3QMf (ORCPT ); Sun, 30 Jul 2006 12:12:35 -0400 Subject: Re: [PATCH for 2.6.18] [8/8] MM: Remove rogue readahead printk From: Trond Myklebust To: Andrew Morton Cc: nate.diller@gmail.com, ak@suse.de, torvalds@osdl.org, discuss@x86-64.org, linux-kernel@vger.kernel.org In-Reply-To: <20060729232625.c8bcac66.akpm@osdl.org> References: <44cbba3f.mPUieUe31/EOZ6FZ%ak@suse.de> <1154207668.5784.35.camel@localhost> <5c49b0ed0607291804j28193807t83d8237cad8d5ecd@mail.gmail.com> <1154233334.5784.93.camel@localhost> <20060729232625.c8bcac66.akpm@osdl.org> Content-Type: text/plain Date: Sun, 30 Jul 2006 12:12:21 -0400 Message-Id: <1154275941.5784.131.camel@localhost> Mime-Version: 1.0 X-Mailer: Evolution 2.6.1 Content-Transfer-Encoding: 7bit X-UiO-Spam-info: not spam, SpamAssassin (score=-2.279, required 12, autolearn=disabled, AWL 0.21, RCVD_IN_XBL 2.51, UIO_MAIL_IS_INTERNAL -5.00) Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org On Sat, 2006-07-29 at 23:26 -0700, Andrew Morton wrote: > On Sun, 30 Jul 2006 00:22:14 -0400 > Trond Myklebust wrote: > > > > of course, it could be that some quirk of the NFS client VFS interface > > > causes "spurious" -EIO returns. either way, i'd rather see it fixed > > > rather than the printk removed, since it is useful to point out that > > > some performance degradation is occuring. > > > > We have no way of telling. That printk doesn't give us any useful > > information whatsoever for debugging that sort of problem. It should > > either be replaced with something that does, or it should be thrown out. > > err, the printk has found a probable bug in NFS. That was pretty useful > of it. Not necessarily. AFAICS, the spam could be triggered by perfectly legitimate activity. For instance, someone on the server may have revoked your read permissions to the file, or may have deleted it. > Do we know why nfs's readpage isn't bringing the page up to date? It may be that other lurking issues were also triggering the printk. For instance I know of a couple of corner cases in the krb5 privacy code that could result in readpage failing. Those issues are being looked into. Cheers, Trond