Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1758146AbXIKVmN (ORCPT ); Tue, 11 Sep 2007 17:42:13 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1751474AbXIKVlx (ORCPT ); Tue, 11 Sep 2007 17:41:53 -0400 Received: from netops-testserver-4-out.sgi.com ([192.48.171.29]:35527 "EHLO relay.sgi.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1751357AbXIKVlw (ORCPT ); Tue, 11 Sep 2007 17:41:52 -0400 Date: Tue, 11 Sep 2007 14:41:49 -0700 (PDT) From: Christoph Lameter X-X-Sender: clameter@schroedinger.engr.sgi.com To: Nick Piggin cc: Mel Gorman , andrea@suse.de, torvalds@linux-foundation.org, linux-fsdevel@vger.kernel.org, linux-kernel@vger.kernel.org, Christoph Hellwig , Mel Gorman , William Lee Irwin III , David Chinner , Jens Axboe , Badari Pulavarty , Maxim Levitsky , Fengguang Wu , swin wang , totty.lu@gmail.com, hugh@veritas.com, joern@lazybastard.org Subject: Re: [00/41] Large Blocksize Support V7 (adds memmap support) In-Reply-To: <200709111530.16136.nickpiggin@yahoo.com.au> Message-ID: References: <20070911060349.993975297@sgi.com> <200709111453.42650.nickpiggin@yahoo.com.au> <200709111530.16136.nickpiggin@yahoo.com.au> MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 848 Lines: 20 On Tue, 11 Sep 2007, Nick Piggin wrote: > I think I would have as good a shot as any to write a fragmentation > exploit, yes. I think I've given you enough info to do the same, so I'd > like to hear a reason why it is not a problem. No you have not explained why the theoretical issues continue to exist given even just considering Lumpy Reclaim in .23 nor what effect the antifrag patchset would have. And you have used a 2M pagesize which is irrelevant to this patchset that deals with blocksizes up to 64k. In my experience the use of blocksize < PAGE_COSTLY_ORDER (32k) is reasonably safe. - 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/