From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: with ECARTIS (v1.0.0; list xfs); Tue, 24 Oct 2006 10:41:23 -0700 (PDT) Received: from cuda.sgi.com (cuda2.sgi.com [192.48.168.29]) by oss.sgi.com (8.12.10/8.12.10/SuSE Linux 0.7) with ESMTP id k9OHf4aG009559 for ; Tue, 24 Oct 2006 10:41:07 -0700 Subject: Re: [PATCH] Freeze bdevs when freezing processes. References: <1161576735.3466.7.camel@nigel.suspend2.net> <200610231236.54317.rjw@sisk.pl> <20061024144446.GD11034@melbourne.sgi.com> <200610241730.00488.rjw@sisk.pl> Date: Tue, 24 Oct 2006 16:27:08 +0000 Message-ID: From: Oleg Verych Sender: xfs-bounce@oss.sgi.com Errors-to: xfs-bounce@oss.sgi.com List-Id: xfs To: "Rafael J. Wysocki" , David Chinner , Nigel Cunningham , Andrew Morton , Pavel Machek , xfs@oss.sgi.com, Oleg Verych On 2006-10-24, Rafael J. Wysocki wrote: > On Tuesday, 24 October 2006 16:44, David Chinner wrote: >> On Mon, Oct 23, 2006 at 12:36:53PM +0200, Rafael J. Wysocki wrote: >> > On Monday, 23 October 2006 06:12, Nigel Cunningham wrote: >> > > XFS can continue to submit I/O from a timer routine, even after >> > > freezeable kernel and userspace threads are frozen. This doesn't seem to >> > > be an issue for current swsusp code, >> > >> > So it doesn't look like we need the patch _now_. >> > >> > > but is definitely an issue for Suspend2, where the pages being written could >> > > be overwritten by Suspend2's atomic copy. >> > >> > And IMO that's a good reason why we shouldn't use RCU pages for storing the >> > image. XFS is one known example that breaks things if we do so and >> > there may be more such things that we don't know of. The fact that they >> > haven't appeared in testing so far doesn't mean they don't exist and >> > moreover some things like that may appear in the future. >> >> Could you please tell us which XFS bits are broken so we can get >> them fixed? The XFS daemons should all be checking if they are >> supposed to freeze (i.e. they call try_to_freeze() after they wake >> up due to timer expiry) so I thought they were doing the right >> thing. >> >> However, I have to say that I agree with freezing the filesystems >> before suspend - at least XFS will be in a consistent state that can >> be recovered from without corruption if your machine fails to >> resume.... > > Do you mean calling sys_sync() after the userspace has been frozen > may not be sufficient? Please see it's bottom of IMHO it's may be helpful. -o--=O`C #oo'L O <___=E M