From mboxrd@z Thu Jan 1 00:00:00 1970 From: Bas van der Vlies Subject: Re: NFSD/gfs crashes with oops Date: Thu, 09 Mar 2006 08:39:23 +0100 Message-ID: <440FDBAB.3000603@sara.nl> References: <5F4E2391-4553-4A5A-8A92-1033CE717267@sara.nl> <440EE57B.2090804@sara.nl> <1141830321.8214.21.camel@lade.trondhjem.org> <440EF6E4.4080109@sara.nl> <1141832193.8214.27.camel@lade.trondhjem.org> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1; format=flowed Return-path: Received: from sc8-sf-mx2-b.sourceforge.net ([10.3.1.92] helo=mail.sourceforge.net) by sc8-sf-list2.sourceforge.net with esmtp (Exim 4.30) id 1FHFkD-00054D-OY for nfs@lists.sourceforge.net; Wed, 08 Mar 2006 23:39:33 -0800 Received: from surfboard.ka.sara.nl ([145.100.6.3]) by mail.sourceforge.net with esmtp (Exim 4.44) id 1FHFkD-0002AD-H1 for nfs@lists.sourceforge.net; Wed, 08 Mar 2006 23:39:33 -0800 To: nfs@lists.sourceforge.net In-Reply-To: <1141832193.8214.27.camel@lade.trondhjem.org> Sender: nfs-admin@lists.sourceforge.net Errors-To: nfs-admin@lists.sourceforge.net List-Unsubscribe: , List-Id: Discussion of NFS under Linux development, interoperability, and testing. List-Post: List-Help: List-Subscribe: , List-Archive: Just for the recorde. The GFS guys have made a patch for the crash in CVS stable: CVSROOT: /cvs/cluster Module name: cluster Branch: STABLE Changes by: bmarzins@sourceware.org 2006-03-08 20:47:09 Modified files: gfs-kernel/src/gfs: ops_inode.c Log message: Really gross hack!!! This is a workaround for one of the bugs the got lumped into 166701. It breaks POSIX behavior in a corner case to avoid crashing... It's icky. when NFS opens a file with O_CREAT, the kernel nfs daemon checks to see if the file exists. If it does, nfsd does the *right thing* (either opens the file, or if the file was opened with O_EXCL, returns an error). If the file doesn't exist, it passes the request down to the underlying file system. Unfortunately, since nfs *knows* that the file doesn't exist, it doesn't bother to pass a nameidata structure, which would include the intent information. However since gfs is a cluster file system, the file could have been created on another node after nfs checks for it. If this is the case, gfs needs the intent information to do the *right thing*. It panics when it finds a NULL pointer, instead of the nameidata. Now, instead of panicing, if gfs finds a NULL nameidata pointer. It assumes that the file was not created with _EXCL. This assumption could be wrong, with the result that an application could thing that it has created a new file, when in fact, it has opened an existing one. -- -- ******************************************************************** * * * Bas van der Vlies e-mail: basv@sara.nl * * SARA - Academic Computing Services phone: +31 20 592 8012 * * Kruislaan 415 fax: +31 20 6683167 * * 1098 SJ Amsterdam * * * ******************************************************************** ------------------------------------------------------- This SF.Net email is sponsored by xPML, a groundbreaking scripting language that extends applications into web and mobile media. Attend the live webcast and join the prime developer group breaking into this new coding territory! http://sel.as-us.falkag.net/sel?cmd=lnk&kid=110944&bid=241720&dat=121642 _______________________________________________ NFS maillist - NFS@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/nfs