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From:   Sergey Senozhatsky <sergey.senozhatsky@gmail.com>
Date:   Thu, 30 Jan 2020 01:50:53 +0900
To:     Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Cc:     Sergey Senozhatsky <sergey.senozhatsky.work@gmail.com>,
        Petr Mladek <pmladek@suse.com>,
        Steven Rostedt <rostedt@goodmis.org>,
        linux-kernel@vger.kernel.org,
        Sergey Senozhatsky <sergey.senozhatsky@gmail.com>
Subject: Re: [PATCH v3 5/5] console: Introduce ->exit() callback
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On (20/01/30 00:12), Sergey Senozhatsky wrote:
> On (20/01/29 16:25), Andy Shevchenko wrote:
> > I understand. Seems the ->setup() has to be idempotent. We can tell the same
> > for ->exit() in some comment.
> > 
> > Can you describe, btw, struct console in kernel doc format?
> > It will be very helpful!
> 
> We probably need some documentation.
> 
> > > > In both cases we will get the console to have CON_ENABLED flag set.
> > > 
> > > And there are sneaky consoles that have CON_ENABLED before we even
> > > register them.
> > 
> > So, taking into consideration my comment to the previous patch, what would be
> > suggested guard here?
> > 
> > For a starter something like this?
> > 
> >   if ((console->flags & CON_ENABLED) && console->exit)
> > 	console->exit(console);
> 
> This will work if we also add something like this

No, wait... This will not work, console can be suspended, yet
still registered. I think the only criteria is "the console is
on the list".

	-ss