From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S263809AbTDDQPf (for ); Fri, 4 Apr 2003 11:15:35 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S263803AbTDDQHc (for ); Fri, 4 Apr 2003 11:07:32 -0500 Received: from holomorphy.com ([66.224.33.161]:48017 "EHLO holomorphy") by vger.kernel.org with ESMTP id S263802AbTDDQDy (for ); Fri, 4 Apr 2003 11:03:54 -0500 Date: Fri, 4 Apr 2003 08:14:57 -0800 From: William Lee Irwin III To: Hugh Dickins Cc: Andrew Morton , Dave McCracken , linux-kernel@vger.kernel.org, linux-mm@kvack.org Subject: Re: objrmap and vmtruncate Message-ID: <20030404161457.GE993@holomorphy.com> Mail-Followup-To: William Lee Irwin III , Hugh Dickins , Andrew Morton , Dave McCracken , linux-kernel@vger.kernel.org, linux-mm@kvack.org References: Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: User-Agent: Mutt/1.3.28i Organization: The Domain of Holomorphy Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org On Fri, Apr 04, 2003 at 03:34:48PM +0100, Hugh Dickins wrote: > I see you're going for locking the page around page_convert_anon, > to guard page->mapping against truncation. Nice thought, > but the words "tip" and "iceberg" spring to mind. > Truncating a sys_remap_file_pages file? You're the first to > begin to consider such an absurd possibility: vmtruncate_list > still believes vm_pgoff tells it what needs to be done. > I propose that we don't change vmtruncate_list, zap_page_range, ... > at all for this: let it unmap inappropriate pages, even from a > VM_LOCKED vma, that's just a price userspace pays for the > privilege of truncating a sys_remap_file_pages file. Hmm, aren't the file offset calculations wrong for sys_remap_file_pages() even before objrmap? -- wli