Re: [PATCH/RFC] Add support to resume swsusp from initrd

[Matthew Garrett <mjg59@srcf.ucam.org>]

On Sun, 2004-12-05 at 22:29 +0100, Pavel Machek wrote:

> > resume_device is set by swsusp_read, which requires name_to_dev_t to be
> > working. At the point where that's called, the device driver hasn't been
> > loaded and we don't have the information to get the dev_t. Once the
> > driver has been loaded, name_to_dev_t has already been discarded (it's
> > marked __init). So we need to set resume_device somehow.
> 
> What about move of resume_device setup somewhere sooner?

Ah - we could always set resume_device, even if there's nothing to
resume. That way, it'd be set correctly for userspace later on. Ok, I
think I can make that work.

> > Heh. Yes, that's no problem. A new bigdiff for -rc3 would be
> > helpful.
> 
> Hmm, I'm still on 2.6.9, but this code did not change much. I'll
> generate it.

Thanks!

> > Ok. I'll look into that. The main reason I want code like this is that
> > Debian use modular IDE drivers that are stored in the initrd. The disks
> > won't be touched until the root file system is mounted, and we'll
> > trigger the resume before then, so there shouldn't be any risk of data
> > loss. At this point, there shouldn't be any userspace running other than
> > a single shell script - do you think it's still a problem?
> 
> Single shell script would probably do no harm, but then, you want this
> to go into mainline, not into Debian kernel, right? ;-).

Heh.

> Actually freezing processes is good thing to do even for normal
> resume. We pretty much know there are no harmfull processes running
> there, but better safe than sorry.

Ok, I'll deal with that once I've got the post 2.6.10 code to work with.

Thanks!
-- 
Matthew Garrett | mjg59@srcf.ucam.org