Re: Wait for console to become available, v3.2

From: David Woodhouse
Date: Tue Apr 21 2009 - 13:43:17 EST


On Tue, 2009-04-21 at 10:29 -0700, David VomLehn wrote:
> On Tue, Apr 21, 2009 at 06:11:11PM +0100, David Woodhouse wrote:
> ...
> > The kernel output is going to be spewed when a console registers with
> > CON_PRINTBUFFER anyway, and if we printk a warning about userspace
> > console output being lost, that ought to be good enough to notify the
> > user that something may have been lost. For bonus points, we could even
> > make that 'dummy' tty driver buffer a limited amount of userspace
> > output, maybe.
>
> What in the world are users going to do when they see a message about
> output being lost? There is no way to recover the data and no way to
> prevent it in the future. I don't think this is a good approach.
>
> Remember, even though the previous functionality of USB consoles was, in
> theory, less reliable than it appeared, it actually has been working well
> for years. Thus, tossing output will count as a regression for most of the
> world.

So implement a small amount of buffering, as I suggested, and it should
be sufficient to cover the cases that were only working before by blind
luck anyway.

--
David Woodhouse Open Source Technology Centre
David.Woodhouse@xxxxxxxxx Intel Corporation

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