[CRIU] Re: [PATCH 5/6] tty: Restore orphan slavery peers

[Pavel Emelyanov]

On 09/14/2012 03:48 PM, Cyrill Gorcunov wrote:
> On Fri, Sep 14, 2012 at 03:12:56PM +0400, Pavel Emelyanov wrote:
>> On 09/14/2012 02:38 PM, Cyrill Gorcunov wrote:
>>>
>>> In case if there is no master peer associated
>>> with a slave peer we have two cases
>>>
>>>  - the master peer was closed before slave
>>>  - we just have no master peer at all, but
>>>    only slave one
>>
>> Remove the 2nd case from patch. It should be implemented with
>> Andrey's non-existing sids/pgids.
> 
> Here is just first problem only addressed.

> @@ -144,6 +144,10 @@ static int prepare_shared(void)
>  		goto err;
>  
>  	mark_pipe_master();
> +	ret = tty_setup_orphan_slavery(&opts);

Why not call it from collect_tty()?

> +	if (ret)
> +		goto err;
> +
>  
>  	ret = tty_prepare_shared();
>  	if (ret)

> @@ -80,6 +80,9 @@ struct tty_info {
>  
>  	struct list_head		sibling;
>  	int				major;
> +
> +	bool				create;
> +	bool				noparams;

Unused.

>  };
>  
>  static LIST_HEAD(all_tty_info_entries);

> @@ -674,11 +755,13 @@ static int verify_info(struct tty_info *info)
>  			pr_err("Corrupted slave peer %x\n", info->tfe->id);
>  			return -1;
>  		}
> -	}
>  
> -	if (verify_termios(info->tfe->id, info->tie->termios_locked) ||
> -	    verify_termios(info->tfe->id, info->tie->termios))
> -		return -1;
> +		info->noparams = true;
> +	} else {
> +		if (verify_termios(info->tfe->id, info->tie->termios_locked) ||
> +		    verify_termios(info->tfe->id, info->tie->termios))
> +			return -1;
> +	}

What the heck is that?

>  
>  	if (!pty_is_master(info)) {
>  		if (info->tie->sid || info->tie->pgrp)

> +int tty_setup_orphan_slavery(const struct cr_options *opts)
> +{
> +	struct tty_info *info, *peer, *m;
> +
> +	list_for_each_entry(info, &all_ttys, list) {
> +		struct fdinfo_list_entry *a, *b;
> +		bool has_leader = false;
> +
> +		if (pty_is_master(info))
> +			continue;
> +
> +		a = file_master(&info->d);
> +		m = info;
> +
> +		list_for_each_entry(peer, &info->sibling, sibling) {
> +			if (pty_is_master(peer)) {
> +				has_leader = true;
> +				break;
> +			}
> +
> +			b = file_master(&peer->d);
> +			if (a->pid > b->pid ||
> +			    (a->pid == b->pid && a->fe->fd > b->fe->fd)) {
> +				a = b;
> +				m = peer;
> +			}
> +		}
> +
> +		/* Here is new one */
> +		if (!has_leader) {
> +			m->create = true;
> +			pr_debug("Found orphan slave fake leader (%#x)\n",
> +				 m->tfe->id);
> +		}
> +	}
> +
> +	return 0;

Why not do it with tty_setup_slavery?

> +}
> +