[Devel] [RFC rh7 v2] ve/tty: vt -- Implement per VE support for console and terminals

[Vladimir Davydov]

On Thu, Aug 06, 2015 at 02:01:57PM +0300, Cyrill Gorcunov wrote:
> On Thu, Aug 06, 2015 at 01:48:08PM +0300, Vladimir Davydov wrote:
> > > Maybe let gather all ioctls we won't be able to escape using into
> > > one place and check what we can do?
> > 
> > I don't think it's strictly necessary - we can do it in the course of
> > porting old APIs. We just need to refine our policy:
> > 
> >  - Everything that has to be configured at restore must be moved to the
> >    ve cgroup right now for the sake of criu.
> > 
> > Then having ve.features, ve.os_release, etc perfectly makes sense. Still
> > VE_CONFIGURE_OPEN_TTY should be left as an ioctl according to our new
> > policy.
> 
> Agreed. VE_CONFIGURE_OPEN_TTY is special unfortunately (and could you
> enlighten me a bit -- when console is attached, is it allowed to
> do c/r in our pcs6, i somehow forget,

You can attach to the console using `vzctl console $CTID`. I just
checked - checkpoint/restore is allowed.

> and if yes I'm not yet sure how we will be restoring it in criu).

Good question. I don't know the answer.

FWIW the patch that added vtty cpt/rst support is called
diff-cpt-vtty-support-and-cleanups