Re: [PATCH] drm/i915: Clamp cursor coordinates to int16_t range

Chris Wilson
2013-10-21T16:13:47Z

On Mon, Oct 21, 2013 at 07:01:58PM +0300, ville.syrjala@linux.intel.com wrote:
> From: Ville Syrjälä <ville.syrjala@linux.intel.com>
>
> We store cursor_x/y as int16_t internally, but the user provided
> coordinates are int32_t. Clamp the coordinates so that they don't
> overflow the int16_t. Since the cursor is only 64x64 in size, the
> clamping can't cause any visual changes.

EINVAL? That would appear to be a nuisance as we don't already tell the
user off for being silly with the cursor position.

Bump the internal range? Future proof against tomorrow's 64k
super-ultra-high definition monitors?

The valid range for cursor is currently (-64, 8192) and we don't compute
relative cursor position, so we will be fine for a few years yet with
int16_t.

> Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>
-Chris

--
Chris Wilson, Intel Open Source Technology Centre