Re: [PATCH] drm/i915: grab a pages pin count for preallocate stolen

[Ben Widawsky <benjamin.widawsky@intel.com>]

On Tue, Dec 17, 2013 at 11:42:11PM +0100, Daniel Vetter wrote:
> But only when we indeed set up a gtt mapping. We need this since the
> vma also holds a pages_pin_count, on top of the unconditional
> pages_pin_count we grab for all stolen objects (to avoid swap-out).
> 
> This should avoid a pages_pin_count underrun when cleaning up
> framebuffers objects taken over from the BIOS.
> 
> Reported-by: Jesse Barnes <jbarnes@virtuousgeek.org>
> Cc: Jesse Barnes <jbarnes@virtuousgeek.org>
> Cc: Ben Widawsky <benjamin.widawsky@intel.com>
> Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
> ---
>  drivers/gpu/drm/i915/i915_gem_stolen.c | 1 +
>  1 file changed, 1 insertion(+)
> 
> diff --git a/drivers/gpu/drm/i915/i915_gem_stolen.c b/drivers/gpu/drm/i915/i915_gem_stolen.c
> index d284d892ed94..fed87ec17211 100644
> --- a/drivers/gpu/drm/i915/i915_gem_stolen.c
> +++ b/drivers/gpu/drm/i915/i915_gem_stolen.c
> @@ -420,6 +420,7 @@ i915_gem_object_create_stolen_for_preallocated(struct drm_device *dev,
>  
>  	list_add_tail(&obj->global_list, &dev_priv->mm.bound_list);
>  	list_add_tail(&vma->mm_list, &ggtt->inactive_list);
> +	i915_gem_object_pin_pages(obj);
>  
>  	return obj;
>  
> -- 
> 1.8.4.3
> 

I'm missing why _i915_gem_object_create_stolen() isn't good enough for
pinning the pages.

-- 
Ben Widawsky, Intel Open Source Technology Center