Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756772AbXEQMGT (ORCPT ); Thu, 17 May 2007 08:06:19 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1755646AbXEQMGM (ORCPT ); Thu, 17 May 2007 08:06:12 -0400 Received: from pentafluge.infradead.org ([213.146.154.40]:41063 "EHLO pentafluge.infradead.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755181AbXEQMGM (ORCPT ); Thu, 17 May 2007 08:06:12 -0400 Date: Thu, 17 May 2007 05:04:23 -0700 From: Greg KH To: Tejun Heo Cc: Andrew Morton , Clemens Schwaighofer , linux-kernel , Maneesh Soni , Dipankar Sarma , Chuck Ebbert Subject: Re: [PATCH -stable] sysfs: disable reclamation by default Message-ID: <20070517120423.GE17712@kroah.com> References: <464A4F56.6080108@tequila.co.jp> <20070515185350.2e77bf21.akpm@linux-foundation.org> <464AE56F.3040101@gmail.com> <20070516082935.fe112ab5.akpm@linux-foundation.org> <464B2605.9040200@gmail.com> <20070516091346.3c76cb46.akpm@linux-foundation.org> <464B4DE4.9060100@gmail.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <464B4DE4.9060100@gmail.com> User-Agent: Mutt/1.5.15 (2007-04-06) Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1128 Lines: 27 On Wed, May 16, 2007 at 08:31:00PM +0200, Tejun Heo wrote: > sd->s_dentry updates made by dentry/inode reclamation are racy and can > lead to BUG() or oops. This is already fixed in -mm and the fix is > scheduled to be merged into upstream for 2.6.23 but the fix > reimplements sysfs dentry dropping and is too risky for -stable > kernels. > > This is an interim solution for -stable kernels. sysfs reclamation is > disabled by default and can be enabled by using sysfs.enable_reclaim > kernel parameter. Note that dentries are still created on demand, so > attribute and symlinks nodes aren't allocated on creation. They're > allocated on first lookup and deallocated when the sysfs node is > removed. Ick, this is going to kill memory on big boxes (s390 and others) and I don't really want to apply this it if at all possible. Maneesh, any other thoughts? thanks, greg k-h - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/