Hi.

On Wed, 2007-05-30 at 16:04 +0200, Rafael J. Wysocki wrote:
quoted text
> On Wednesday, 30 May 2007 15:17, Nigel Cunningham wrote:
> > On Wed, 2007-05-30 at 13:40 +0100, Matthew Garrett wrote:
> > > On Wed, May 30, 2007 at 01:49:21PM +0200, Pavel Machek wrote:
> > >=20
> > > (Trimmed the Cc:s quite heavily - I think this has gone somewhere bey=
ond=20
quoted text
> > > the original point)
> > >=20
> > > > Notice that we want to be able to suspend while hibernating -- for
> > > > suspend to both behaviour. So drivers may _not_ rely on system bein=
g
quoted text
> > > > runnable.
> > >=20
> > > So keep the driver layers read-only and unfreeze the processes after=20
> > > doing the atomic copy.
> >=20
> > I know you probably won't care, but that's not an option for Suspend2 -
> > I get the possibility of a full image by overwriting LRU pages that wer=
e
quoted text
> > saved prior to the atomic copy.
>=20
> This generally is a problem, not only for suspend2. :-)
>=20
> Once you've unfrozen the user land, we can't rely on the hibernation imag=
e any
quoted text
> more, because some tasks may cause the on-disk filesystems' state to chan=
ge.

True. I understood, perhaps wrongly, that when Matthew spoke of keeping
the drivers layers read-only, he was meaning stopping filesystem changes
by some other means.

Regards,

Nigel