[CRIU] Dealing with other mount types

[Andrew Vagin]

On Thu, Mar 26, 2015 at 09:03:35AM -0600, Tycho Andersen wrote:
> On Thu, Mar 26, 2015 at 05:59:30PM +0300, Pavel Emelyanov wrote:
> > 
> > >>> I have written a test which reproduces this configuration and CRIU
> > >>> doesn't report any error. The test fails as expected, becuase CRIU
> > >>> doesn't support read-only bind-mounts.
> > >>
> > >> I've sent my test in the ML:
> > >> [PATCH] test: check read-only bind-mounts
> > > 
> > > Yes, I've just checked the patch and I see the same behavior. I think
> > > I was confused about what was going on before.
> > > 
> > > One thing is, with some patches to lxc I can actually c/r containers
> > > in this configuration, but your test seems to indicate that things
> > > will fail if something in the restored container tries to access files
> > > here. Is this something we should explicitly disallow?
> > 
> > Wait a second, guys :) I thought that Tycho meant that CRIU failed to dump such
> > mount points knot. Now it looks like CRIU can C/R it, but the restored result is
> > not correct.
> 
> Yes, I was getting confused with another problem we have w.r.t. mount
> points in unprivileged containers (but unprivileged containers have
> lots of other problems too :). Andrew is right that what I was
> describing is not the problem. There is another problem though,
> 
> > So what the problem is?
> 
> I think it's that files in the restored container's r/o bind mounts
> can't actually be accessed, but Andrew can probably elaborate.

We need to add support for read-only bind-mounts.

> 
> Tycho
> 
> > -- Pavel
> >