From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S263370AbUCPBmj (ORCPT ); Mon, 15 Mar 2004 20:42:39 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S263398AbUCPBmE (ORCPT ); Mon, 15 Mar 2004 20:42:04 -0500 Received: from mail.tpgi.com.au ([203.12.160.61]:36234 "EHLO mail4.tpgi.com.au") by vger.kernel.org with ESMTP id S262907AbUCPBhW (ORCPT ); Mon, 15 Mar 2004 20:37:22 -0500 Subject: Re: Dealing with swsusp vs. pmdisk From: Nigel Cunningham Reply-To: ncunningham@users.sourceforge.net To: Benjamin Herrenschmidt Cc: Pavel Machek , "Theodore Ts'o" , Linux Kernel Mailing List In-Reply-To: <1079395292.2302.191.camel@gaston> References: <20040312224645.GA326@elf.ucw.cz> <20040313004756.GB5115@thunk.org> <1079146273.1967.63.camel@gaston> <20040313123620.GA3352@openzaurus.ucw.cz> <1079223482.1960.113.camel@gaston> <20040314003717.GI549@elf.ucw.cz> <1079381114.5349.62.camel@calvin.wpcb.org.au> <1079395292.2302.191.camel@gaston> Content-Type: text/plain Message-Id: <1079393514.2043.10.camel@calvin.wpcb.org.au> Mime-Version: 1.0 X-Mailer: Ximian Evolution 1.4.5-2.norlug Date: Tue, 16 Mar 2004 12:31:55 +1300 Content-Transfer-Encoding: 7bit X-TPG-Antivirus: Passed Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Hi. On Tue, 2004-03-16 at 13:01, Benjamin Herrenschmidt wrote: > > - Freezer hooks (I can easily get suspend2 working with the old freezer > > until people are convinced it's not up to the task). This accounts for > > the vast majority of those file changes. > > It would be nice if you did that as a first step indeed. I'm personally > not convinced of the usefullness of having a freezer at all ;) Without a freezer, how would you ensure that other processes don't mess up your memory state while you're saving/reloading the image? > Some of the "guard" code you added to the filesystem is scary too.. It's really just paranoia, particularly for where swapfiles are in use. While developing the swapfile support, I had a couple of occasions where I messed up my superblock because of a bug. I'm very confident now that the suspend code itself is stable and mature, but since the device drivers aren't there, I'd rather not remove the safety nets just yet. Nigel -- Nigel Cunningham C/- Westminster Presbyterian Church Belconnen 61 Templeton Street, Cook, ACT 2614. +61 (2) 6251 7727(wk); +61 (2) 6253 0250 (home) Evolution (n): A hypothetical process whereby infinitely improbable events occur with alarming frequency, order arises from chaos, and no one is given credit.