Re: swsusp: move resume before mounting root [diff against vanilla 2.4.9]

Pavel Machek
2001-09-27T14:34:20Z

Hi!

> >> Solution for the filesystem problems:
> >>
> >> 1. at suspend, basically unmount the filesystem (keep the mount tree)
> >> 2. at resume, re-validate open files
> >
> > Wrong solution. ;-).
> >
> > Solution to filesystem problems: at suspend, sync but don't do
> > anything more. At resume, don't try to mount anything (so that you
> > don't replay transactions or damage disk in any other way).
>
> That is totally broken, because I may mount the disk in between
> the suspend and resume. I might even:
>
> 1. boot kernel X
> 2. suspend kernel X
> 3. boot kernel Y
> 4. suspend kernel Y
> 5. resume kernel X
> 6. suspend kernel X
> 7. resume kernel Y
> 8. suspend kernel Y
> 9. goto #5
>
> You really have to close the logs and mark the disks clean
> when you suspend. The problems here are similar the the ones

I can't do that: open deleted files.

> NFS faces. Between the suspend and resume, filesystems may be
> modified in arbitrary ways.

No, you don't want to do that. This is swsusp package, meant to
replace suspend-to-disk on your notebook. If you choose random
notebook, it will allow you to suspend to disk, but not to suspend,
boot X, poweron, boot Y, reboot, boot X.

If you do what you described, you'll corrupt your filesystem. It is
designed that way.
Pavel
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