From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: with ECARTIS (v1.0.0; list xfs); Sun, 23 Jul 2006 13:06:33 -0700 (PDT) Received: from pentafluge.infradead.org (pentafluge.infradead.org [213.146.154.40]) by oss.sgi.com (8.12.10/8.12.10/SuSE Linux 0.7) with ESMTP id k6NK68DW030214 for ; Sun, 23 Jul 2006 13:06:08 -0700 Date: Sun, 23 Jul 2006 20:06:50 +0100 From: Christoph Hellwig Subject: Re: review: fix remount vs barrier options Message-ID: <20060723190650.GA22180@infradead.org> References: <20060721152807.D1998769@wobbly.melbourne.sgi.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20060721152807.D1998769@wobbly.melbourne.sgi.com> Sender: xfs-bounce@oss.sgi.com Errors-To: xfs-bounce@oss.sgi.com List-Id: xfs To: Nathan Scott Cc: xfs@oss.sgi.com, jeremy@sgi.com > It finally clicked that we are not clearing the buffer flag > from a previously written log buffer, even though we'll no > longer set a new flag into a buffer (due to the mount flag > being cleared), so we _can_ still issue barrier writes when > remounted without barriers. That's true. Ooops. > This was made more complicated by the way a freshly mounted > filesystem with 8 log buffers wouldn't show up the problem, > since we have to slowly cycle through the "clear" log buffers > before we see the bug. This seems like the simplest fix... > > (Hmmm, actually, I wonder if this will also resolve the quota > log I/O problem that was reported the other day too). Shouldn't we make sure we clear all flags when reusing a log buffer? Relying on clearing individual flags seems rather fragile to me.