From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: with ECARTIS (v1.0.0; list xfs); Wed, 06 Aug 2008 12:55:18 -0700 (PDT) Received: from cuda.sgi.com (cuda2.sgi.com [192.48.168.29]) by oss.sgi.com (8.12.11.20060308/8.12.11/SuSE Linux 0.7) with ESMTP id m76JtCOq007239 for ; Wed, 6 Aug 2008 12:55:12 -0700 Message-ID: <489A01E1.1040309@sandeen.net> Date: Wed, 06 Aug 2008 14:56:17 -0500 From: Eric Sandeen MIME-Version: 1.0 Subject: Re: TAKE 981498 - Use KM_NOFS for debug trace buffers References: <20080806061553.A8D8958C52A4@chook.melbourne.sgi.com> In-Reply-To: Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Sender: xfs-bounce@oss.sgi.com Errors-to: xfs-bounce@oss.sgi.com List-Id: xfs To: Bhagi rathi Cc: Lachlan McIlroy , sgi.bugs.xfs@engr.sgi.com, xfs@oss.sgi.com Bhagi rathi wrote: > I couldn't get a chance to read the diff's completely. If I click on > Lachlan's url for diff's, I couldn't access them. Try again, it takes a while for cvs to catch up. -Eric > It looks to me that > the issue is not just with trace buffers. It can extend to xfs_iformat > as well. The same dead-lock can spring via > > xfs_iread -> xfs_iformat -> xfs_iformat_extents -> xfs_iext_add -> > xfs_iext_inline_to_direct -> which can do kmem_alloc with > KM_SLEEP flag. > > > The source of the problem is that holding a lock and entering into > file-system once again. This can lead to dead-lock on the same > clustered buffer during cleaning of log space. > > Cheers, > Bhagi.