From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S263311AbTDVRwO (ORCPT ); Tue, 22 Apr 2003 13:52:14 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S263314AbTDVRwO (ORCPT ); Tue, 22 Apr 2003 13:52:14 -0400 Received: from to-telus.redhat.com ([207.219.125.105]:35836 "EHLO touchme.toronto.redhat.com") by vger.kernel.org with ESMTP id S263311AbTDVRwO (ORCPT ); Tue, 22 Apr 2003 13:52:14 -0400 Date: Tue, 22 Apr 2003 14:04:19 -0400 From: Benjamin LaHaise To: Ingo Molnar Cc: linux-kernel@vger.kernel.org, linux-mm@kvack.org Subject: Re: objrmap and vmtruncate Message-ID: <20030422140419.F2944@redhat.com> References: <20030422165746.GK23320@dualathlon.random> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline User-Agent: Mutt/1.2.5.1i In-Reply-To: ; from mingo@redhat.com on Tue, Apr 22, 2003 at 01:34:46PM -0400 Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org On Tue, Apr 22, 2003 at 01:34:46PM -0400, Ingo Molnar wrote: > is anything forcing us to fixing up mappings during a truncate? What we > need is just for the FS to recognize pages behind end-of-inode to still > potentially exist after truncation, if those areas were mapped before the > truncation. Apps that do not keep uptodate with truncaters can get > out-of-date data anyway, via read()/write() anyway. Are there good > arguments to be this strict across truncate()? We sure could make it safe > even thought it's not safe currently. Yes: access beyond EOF is required to SIGBUS according to various standards. But keep in mind that this is a slow path and doesn't have to be anywhere near optimal, unlike page reclaim. -ben -- Junk email? aart@kvack.org