From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754369AbYI0RjA (ORCPT ); Sat, 27 Sep 2008 13:39:00 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1753236AbYI0Rik (ORCPT ); Sat, 27 Sep 2008 13:38:40 -0400 Received: from mail.tmr.com ([64.65.253.246]:37354 "EHLO partygirl.tmr.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754084AbYI0Rij (ORCPT ); Sat, 27 Sep 2008 13:38:39 -0400 Message-ID: <48DE6F93.9030002@tmr.com> Date: Sat, 27 Sep 2008 13:38:27 -0400 From: Bill Davidsen User-Agent: Mozilla/5.0 (X11; U; Linux i686; en-US; rv:1.8.1.16) Gecko/20080716 Fedora/1.1.11-1.fc9 SeaMonkey/1.1.11 MIME-Version: 1.0 To: David Newall CC: Vegard Nossum , linux-kernel@vger.kernel.org Subject: Re: Swap on loop device on tmpfs locks up machine References: <19f34abd0809261146j72a68765i964466336a3a34dc@mail.gmail.com> <48DE2BF7.3060905@davidnewall.com> In-Reply-To: <48DE2BF7.3060905@davidnewall.com> Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org David Newall wrote: > Vegard Nossum wrote: >> It turns out that swap over loop device on tmpfs will lock up the >> machine. > > Doesn't tmpfs use otherwise-free virtual memory? I expect the machine > would lock up if you put swap (i.e. additional virtual memory) on such a > device. To reinstate the paragraph from the O.P. you snipped: >> I'm not sure it's really a very good idea to do this in the first >> place, but should something give a warning or prevent a user from >> doing it? I think you are both right, it is a bad thing to do, it does seem to lock up, and something should prevent a user from doing that. But it may be easier to fix the lockup than get the "prevent" right, there appears to be a loop there. Just a simple questions to the O.P.: what were you thinking?!! Or was this a test just to see what would happen? -- Bill Davidsen "We have more to fear from the bungling of the incompetent than from the machinations of the wicked." - from Slashdot