From mboxrd@z Thu Jan  1 00:00:00 1970
From: "Antonino A. Daplas" <adaplas@gmail.com>
Subject: Re: [Linux-fbdev-devel] Behaviour change of /dev/fb0?
Date: Sat, 15 Apr 2006 07:29:44 +0800
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Cc: linux-kernel@vger.kernel.org, Richard Purdie <rpurdie@rpsys.net>

Richard Purdie wrote:
> Ignoring whether this is a good idea or not, under 2.6.15 you could run
> 
> dd if=/dev/zero of=/dev/fb0
> 
> which would clear the framebuffer. It would end up saying "dd: /dev/fb0:
> No space left on device".
> 
> Under 2.6.16 (and a recent git kernel), the same command clears the
> screen but then hangs. Was the change in behaviour intentional? 
> 
> I've noticed this on a couple of ARM based Zaurus handhelds under both
> w100fb and pxafb.
> 

There is a change in behavior of fb_read and fb_write committed Jan 2006.
They return the number of bytes read or written if the requested size
is bigger than the remaining space.  Previously, they returned -ENOSPC.

But I haven't experienced hangs...

Tony