[CRIU] [PATCH 1/2] mnt: do_new_mount should restore sharing

[Tycho Andersen]

On Fri, Apr 17, 2015 at 06:58:34PM +0300, Andrew Vagin wrote:
> On Wed, Apr 15, 2015 at 01:17:40PM -0600, Tycho Andersen wrote:
> > The function masks off sharing in the initial setting, but doesn't correctly
> > reset the flags afterwards.
> > 
> > CC: Oleg Nesterov <oleg at redhat.com>
> > Signed-off-by: Tycho Andersen <tycho.andersen at canonical.com>
> > ---
> >  mount.c | 4 +++-
> >  1 file changed, 3 insertions(+), 1 deletion(-)
> > 
> > diff --git a/mount.c b/mount.c
> > index 1d8f486..17f97a2 100644
> > --- a/mount.c
> > +++ b/mount.c
> > @@ -1789,7 +1789,9 @@ static int do_new_mount(struct mount_info *mi)
> >  		return -1;
> >  	}
> >  
> > -	if (restore_shared_options(mi, 0, mi->shared_id, 0))
> > +	if (restore_shared_options(mi, !mi->shared_id && !mi->master_id,
> 
> Could you explain this? If we talk about external mount, we need to give
> true here if host_mi->shared_id isn't equal to mi->shared_id.

All external mounts are restored via do_bind_mount(), so the sharing
here is all internal.

However, I think if this mi->shared_id differs from
mi->parent->shared_id we do need to remount private first, since the
internal sharing is different. I can resend with this change if it
makes sense.

Tycho

> > +					mi->shared_id,
> > +					mi->master_id))
> >  		return -1;
> >  
> >  	mi->mounted = true;
> > -- 
> > 2.1.4
> > 
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