From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from cuda.sgi.com (cuda1.sgi.com [192.48.157.11]) by oss.sgi.com (8.14.3/8.14.3/SuSE Linux 0.8) with ESMTP id nALM4PCX062233 for ; Sat, 21 Nov 2009 16:04:26 -0600 Received: from mail.internode.on.net (localhost [127.0.0.1]) by cuda.sgi.com (Spam Firewall) with ESMTP id B98E21346254 for ; Sat, 21 Nov 2009 14:04:47 -0800 (PST) Received: from mail.internode.on.net (bld-mail14.adl6.internode.on.net [150.101.137.99]) by cuda.sgi.com with ESMTP id AOIi0oCJuc4vkXkh for ; Sat, 21 Nov 2009 14:04:47 -0800 (PST) Date: Sun, 22 Nov 2009 09:04:44 +1100 From: Dave Chinner Subject: Re: BUG() in end_page_writeback(), stack overflows and system speed decrease with XFS over USB Message-ID: <20091121220444.GF3804@discord.disaster> References: <200911190957.45957.JuergenUrban@gmx.de> <200911210200.13438.JuergenUrban@gmx.de> <200911211151.23764@zmi.at> <200911211833.20691.JuergenUrban@gmx.de> MIME-Version: 1.0 Content-Disposition: inline In-Reply-To: <200911211833.20691.JuergenUrban@gmx.de> List-Id: XFS Filesystem from SGI List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: xfs-bounces@oss.sgi.com Errors-To: xfs-bounces@oss.sgi.com To: Juergen Urban Cc: xfs@oss.sgi.com On Sat, Nov 21, 2009 at 06:33:20PM +0100, Juergen Urban wrote: > Can someone explain the purpose of the BUG() in end_page_writeback()? Can I > remove the line? A page that is under writeback is supposed to have the PG_writeback flag set. Hence when writeback is completed (i.e the page is now clean) we need to clear the PG_writeback bit. The BUG is triggered if we are ending writeback on a page that does not have PG_writeback set. IOWs, something is seriously wrong, and could be a memory error or memory corruption. > Will XFS also work if I disable all address operations? No. > What is the purpose of the address operations? Reading Documentation/filesystems/vfs.txt might answer your questions.... Cheers, Dave. -- Dave Chinner david@fromorbit.com _______________________________________________ xfs mailing list xfs@oss.sgi.com http://oss.sgi.com/mailman/listinfo/xfs