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Date: Tue, 14 Sep 2010 15:05:39 -0500
From: Scott Wood <scottwood@freescale.com>
To: Alan Cox <alan@lxorguk.ukuu.org.uk>
Subject: Re: [PATCH] hvc_console: fix dropping of characters when output
	byte channel is full
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Cc: kumar.gala@freescale.com, linux-kernel@vger.kernel.org,
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On Tue, 14 Sep 2010 20:44:10 +0100
Alan Cox <alan@lxorguk.ukuu.org.uk> wrote:

> > Yes, hvc_push() reschedules.  It doesn't sit in a tight loop burning
> > electrons!
> > 
> > Can we do something safer&smarter here?
> 
> 
> Its a printk handler - better to lose the bytes than hang the box. I
> think the current code is probably right.

Losing the bytes is unacceptable.  Even if an hvc backend erroneously
returns zero on a permanent error, the timeout should prevent hanging
the box for too long.

Though I suspect the right answer for us may be "don't use the hvc
layer".

-Scott