Re: Fix SWSUSP & !SWAP

From: Pavel Machek (pavel@ucw.cz)
Date: Fri Apr 25 2003 - 07:59:18 EST


Hi!

> > On Apr 24, 2003 22:48 +0200, Pavel Machek wrote:
> > OK, then why all of the talk earlier saying that journal recovery will
> > corrupt a swapfile? That was the reason journaling was brought into the
> > discussion in the first place:
> >
> > "And now you have kernel which expects data still in journal (that was
> > state before suspend), but reality on disk is quite different (journal
> > was replayed). Data corruption." -- Pavel
>
> I don't believe Pavel was saying the image would be corrupted. Rather,
> the rest of the disk contents are corrupted by replaying the journal and
> then resuming back to a memory state that has been made inconsistent
> with the disk state because of the journal replay.

Right.

> > If that is the case, then the only way to avoid this would be to call
> > sync_super_lockfs() on each filesystem before the suspend, which will
> > force the journal to be empty when it returns. That API is supported
> > by all of the journaling filesystems, and is probably a good thing to
> > do anyways, as it will potentially free a lot of dirty data from RAM,
> > and also ensure that the on-disk data is consistent in case the resume
> > isn't handled gracefully.
>
> Sounds like a good idea to me.

When I do sys_sync(), will it trigger that?
                                                                Pavel

-- 
Horseback riding is like software...
...vgf orggre jura vgf serr.
-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@vger.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/



This archive was generated by hypermail 2b29 : Wed Apr 30 2003 - 22:00:21 EST