From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1762650AbXGFHv6 (ORCPT ); Fri, 6 Jul 2007 03:51:58 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1755783AbXGFHvt (ORCPT ); Fri, 6 Jul 2007 03:51:49 -0400 Received: from smtp-out001.kontent.com ([81.88.40.215]:48970 "EHLO smtp-out.kontent.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754030AbXGFHvt (ORCPT ); Fri, 6 Jul 2007 03:51:49 -0400 From: Oliver Neukum To: Miklos Szeredi Subject: Re: [PATCH] Remove process freezer from suspend to RAM pathway Date: Fri, 6 Jul 2007 09:51:47 +0200 User-Agent: KMail/1.9.7 Cc: rjw@sisk.pl, nigel@suspend2.net, pavel@ucw.cz, benh@kernel.crashing.org, mjg59@srcf.ucam.org, linux-kernel@vger.kernel.org, linux-pm@lists.linux-foundation.org References: <20070703042916.GA17240@srcf.ucam.org> <200707060940.23248.rjw@sisk.pl> In-Reply-To: MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: 7bit Content-Disposition: inline Message-Id: <200707060951.47555.oliver@neukum.org> Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Am Freitag, 6. Juli 2007 schrieb Miklos Szeredi: > > > You're missing the point. I'm arguing that a sync from within the freezer > > > should guarantee that there is no data loss. > > > > Well, it should, but it doesn't ... > > > > Moreover, if FUSE implements syncing, then the sync from within the freezer > > will almost certainly deadlock. > > Rafael, think positively: by the time fuse implements sync(), the > freezer will be long gone ;) Now you are entering really dangerous territory. If you can implement a meaningfull sync method, you must have dirty pages in the page cache. That means you are in the page freeing path of the vm. Then we are in real trouble. Don't even think about it. As far as suspend/hibernate is concerned, get yourself on the new notifying chain and revert to synchronous operations when notified. Regards Oliver