From mboxrd@z Thu Jan 1 00:00:00 1970 From: Nigel Cunningham Subject: Re: [RFC][PATCH] PM / Sleep: Freeze filesystems during system suspend/hibernation Date: Thu, 02 Feb 2012 14:17:41 +1100 Message-ID: <4F2A0055.1060306@tuxonice.net> References: <201201281445.49377.rjw@sisk.pl> Mime-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit Cc: Linux PM list , LKML , Jan Kara , linux-fsdevel@vger.kernel.org, Dave Chinner , Pavel Machek , "Srivatsa S. Bhat" To: "Rafael J. Wysocki" Return-path: In-Reply-To: <201201281445.49377.rjw@sisk.pl> Sender: linux-kernel-owner@vger.kernel.org List-Id: linux-fsdevel.vger.kernel.org Hi. On 29/01/12 00:45, Rafael J. Wysocki wrote: > From: Rafael J. Wysocki > > Freeze all filesystems during system suspend and (kernel-driven) > hibernation by calling freeze_supers() for all superblocks and thaw > them during the subsequent resume with the help of thaw_supers(). > > This makes filesystems stay in a consistent state in case something > goes wrong between system suspend (or hibernation) and the subsequent > resume (e.g. journal replays won't be necessary in those cases). In > particular, this should help to solve a long-standing issue that, in > some cases, during resume from hibernation the boot loader causes the > journal to be replied for the filesystem containing the kernel image > and/or initrd causing it to become inconsistent with the information > stored in the hibernation image. > > The user-space-driven hibernation (s2disk) is not covered by this > change, because the freezing of filesystems prevents s2disk from > accessing device special files it needs to do its job. > > This change is based on earlier work by Nigel Cunningham. > > Signed-off-by: Rafael J. Wysocki Acked-by: Nigel Cunningham (Or reviewed by or whatever :> I'm out of the loop too much, and don't remember what the right one is!) -- Evolution (n): A hypothetical process whereby improbable events occur with alarming frequency, order arises from chaos, and no one is given credit.