Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755242AbYKDP5A (ORCPT ); Tue, 4 Nov 2008 10:57:00 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1753560AbYKDP4v (ORCPT ); Tue, 4 Nov 2008 10:56:51 -0500 Received: from zrtps0kn.nortel.com ([47.140.192.55]:63544 "EHLO zrtps0kn.nortel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753520AbYKDP4v (ORCPT ); Tue, 4 Nov 2008 10:56:51 -0500 Message-ID: <491070B5.2060209@nortel.com> Date: Tue, 04 Nov 2008 09:56:37 -0600 From: "Chris Friesen" User-Agent: Thunderbird 2.0.0.17 (X11/20080914) MIME-Version: 1.0 To: Rik van Riel CC: Peter Zijlstra , "Eugene V. Lyubimkin" , linux-kernel@vger.kernel.org, linux-mm , hugh Subject: Re: mmap: is default non-populating behavior stable? References: <490F73CD.4010705@gmail.com> <1225752083.7803.1644.camel@twins> <490F8005.9020708@redhat.com> In-Reply-To: <490F8005.9020708@redhat.com> Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit X-OriginalArrivalTime: 04 Nov 2008 15:56:39.0037 (UTC) FILETIME=[EC2FBAD0:01C93E95] Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 683 Lines: 18 Rik van Riel wrote: > Peter Zijlstra wrote: >> The exact interaction of mmap() and truncate() I'm not exactly clear on. > > Truncate will reduce the size of the mmaps on the file to > match the new file size, so processes accessing beyond the > end of file will get a segmentation fault (SIGSEGV). I suspect Peter was talking about using truncate() to set the initial file size, effectively increasing rather than reducing it. Chris -- 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/