[Intel-gfx] [PATCH] drm/i915: Reject fence stride=0 on gen4+

[Ville Syrjälä]

On Tue, Apr 09, 2013 at 05:01:18PM +0200, Daniel Vetter wrote:
> On Tue, Apr 09, 2013 at 05:46:45PM +0300, ville.syrjala at linux.intel.com wrote:
> > From: Ville Syrjälä <ville.syrjala at linux.intel.com>
> > 
> > Our checks for an invalid fence stride forgot to guard against
> > zero stride on gen4+. Fix it.
> > 
> > Signed-off-by: Ville Syrjälä <ville.syrjala at linux.intel.com>
> 
> This duplicates the tiny stride check a bit with the gen2/3 code. What
> about
> 
> 
> diff --git a/drivers/gpu/drm/i915/i915_gem_tiling.c b/drivers/gpu/drm/i915/i915_gem_tiling.c
> index c807eb9..b56185f 100644
> --- a/drivers/gpu/drm/i915/i915_gem_tiling.c
> +++ b/drivers/gpu/drm/i915/i915_gem_tiling.c
> @@ -235,6 +235,9 @@ i915_tiling_ok(struct drm_device *dev, int stride, int size, int tiling_mode)
>  		}
>  	}
>  
> +	if (stride < tile_width)
> +		return false;
> +
>  	/* 965+ just needs multiples of tile width */
>  	if (INTEL_INFO(dev)->gen >= 4) {
>  		if (stride & (tile_width - 1))
> @@ -243,9 +246,6 @@ i915_tiling_ok(struct drm_device *dev, int stride, int size, int tiling_mode)
>  	}
>  
>  	/* Pre-965 needs power of two tile widths */
> -	if (stride < tile_width)
> -		return false;
> -
>  	if (stride & (stride - 1))
>  		return false;
>  
> instead?

Looks OK. The same idea occured to me, but only after hitting enter.

> -Daniel
> 
> > ---
> >  drivers/gpu/drm/i915/i915_gem_tiling.c | 2 ++
> >  1 file changed, 2 insertions(+)
> > 
> > diff --git a/drivers/gpu/drm/i915/i915_gem_tiling.c b/drivers/gpu/drm/i915/i915_gem_tiling.c
> > index 139d17d..16ff6e7 100644
> > --- a/drivers/gpu/drm/i915/i915_gem_tiling.c
> > +++ b/drivers/gpu/drm/i915/i915_gem_tiling.c
> > @@ -240,6 +240,8 @@ i915_tiling_ok(struct drm_device *dev, int stride, int size, int tiling_mode)
> >  
> >  	/* 965+ just needs multiples of tile width */
> >  	if (INTEL_INFO(dev)->gen >= 4) {
> > +		if (stride < tile_width)
> > +			return false;
> >  		if (stride & (tile_width - 1))
> >  			return false;
> >  		return true;
> > -- 
> > 1.8.1.5
> > 
> > _______________________________________________
> > Intel-gfx mailing list
> > Intel-gfx at lists.freedesktop.org
> > http://lists.freedesktop.org/mailman/listinfo/intel-gfx
> 
> -- 
> Daniel Vetter
> Software Engineer, Intel Corporation
> +41 (0) 79 365 57 48 - http://blog.ffwll.ch

-- 
Ville Syrjälä
Intel OTC