Re: [BIG RFC] Filesystem-based checkpoint

[Dave Hansen <dave-23VcF4HTsmIX0ybBhKVfKdBPR1lH4CV8@public.gmane.org>]

On Tue, 2008-10-28 at 15:56 -0500, Serge E. Hallyn wrote:
> Quoting Dave Hansen (dave-23VcF4HTsmIX0ybBhKVfKdBPR1lH4CV8@public.gmane.org):
> > I hate the syscall.  It's a very un-Linux-y way of doing things.  There,
> 
> Not really the syscall, but the writing to the file from the kernel.
> Any time I see set_fs(KERNEL_DS) i get flashbacks to getting yelled at
> in the 90s :)

Heh.  You security whackos are always getting yelled at for _something_
anyway.

> > I said it.  Here's an alternative.  It still uses the syscall to
> > initiate things, but it uses debugfs to transport the data instead.
> > This is just a concept demonstration.  It doesn't actually work, and I
> > wouldn't be using debugfs in practice.
> 
> It's neat how few lines this took, but I would prefer using a tiny
> custom fs rather than use debugfs for dump and configfs for restore.

Yeah, doing a new FS would certainly be a ton more code.  But, I think
the most important part ends up being how complicated it ends up being
in practice.

It may turn out that refactoring some existing debug/configfs code might
be enough to get us there without too much new code *just* for us.

> If you like I can take a shot at whipping up the new mini-fs, though
> I think you're having fun :)

I need to look into what configfs can give me, next.  I'll keep
playing. :)

I really just wanted to know what Oren and Andrey thought.

-- Dave