[Intel-gfx] [PATCH 2/6] drm/i915: Support for creating Stolen memory backed objects

[Tvrtko Ursulin]

Hi,

On 11/11/15 10:36, ankitprasad.r.sharma at intel.com wrote:
> From: Ankitprasad Sharma <ankitprasad.r.sharma at intel.com>
>
> Extend the drm_i915_gem_create structure to add support for
> creating Stolen memory backed objects. Added a new flag through
> which user can specify the preference to allocate the object from
> stolen memory, which if set, an attempt will be made to allocate
> the object from stolen memory subject to the availability of
> free space in the stolen region.
 >
> v2: Rebased to the latest drm-intel-nightly (Ankit)
>
> v3: Changed versioning of GEM_CREATE param, added new comments (Tvrtko)
>
> v4: Changed size from 32b to 64b to prevent userspace overflow (Tvrtko)
> Corrected function arguments ordering (Chris)

Motivated by some questions raised by Dave I went and looked if there is 
something preventing stolen objects use as batch buffers?

I could not find it myself, so the question is can we end up in the 
relocate_entry_cpu with a batch buffer allocated from stolen, which 
would then call i915_gem_object_get_page and crash?

Regards,

Tvrtko