[CRIU] Re: [PATCH 09/10] tty: Introduce deferred dumping of tty peers

[Cyrill Gorcunov]

On Sat, Oct 27, 2012 at 12:18:45AM +0400, Pavel Emelyanov wrote:
> On 10/27/2012 12:16 AM, Cyrill Gorcunov wrote:
> > On Sat, Oct 27, 2012 at 12:15:23AM +0400, Pavel Emelyanov wrote:
> >>> Thus when we start dumping ptmx peer (which belongs to SCREEN)
> >>> we've not yet constructed the process tree item for children
> >>> (ie /bin/bash) and the lookup function in tty code (which walks
> >>> over all process items in a tree) simply fails to find sid of
> >>> child, because we've not yet dumped it.
> >>
> >> Are we talking about this code
> >>
> >>         if (pti->sid) {
> >>                 struct pstree_item *item = find_first_sid(pti->sid);
> >>                 if (!item || item->pid.virt != pti->sid) {
> >>                         if (!opts.shell_job) {
> >>                                 pr_err("Found sid %d pgid %d on slave peer fd %d. "
> >>                                        "Missing option?\n",
> >>                                        pti->sid, pti->pgrp, p->fd);
> >>                                 return -1;
> >>                         }
> >>                 }
> >>         }
> >>
> >> in dump_pty_info? The find_first_sid() finds nothing, right?
> > 
> > yeah, this is main problem.
> 
> OK. Let's move forward. This find_first_sid() is required to make sure
> that the session leader of tty's session is with us, correct?

Yes, exactly. We need to figure out if we manage to restore this peer.